96-5453. Safety Standards for Underground Coal Mine Ventilation  

  • [Federal Register Volume 61, Number 48 (Monday, March 11, 1996)]
    [Rules and Regulations]
    [Pages 9764-9846]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 96-5453]
    
    
    
    
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    Part III
    
    
    
    
    
    Department of Labor
    
    
    
    
    
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    Mine Safety and Health Administration
    
    
    
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    30 CFR Part 75
    
    
    
    Safety Standards for Underground Coal Mine Ventilation; Final Rule
    
    Federal Register / Vol. 61, No. 48 / Monday, March 11, 1996 / Rules 
    and Regulations 
    
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    DEPARTMENT OF LABOR
    
    Mine Safety and Health Administration
    
    30 CFR Part 75
    
    RIN 1219-AA11
    
    
    Safety Standards for Underground Coal Mine Ventilation
    
    AGENCY: Mine Safety and Health Administration, (MSHA) Labor.
    
    ACTION: Final rule.
    
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    SUMMARY: This final rule revises the Mine Safety and Health 
    Administration's (MSHA's) existing safety standards for ventilation of 
    underground coal mines. After publication of the existing standards, 
    the U.S. Court of Appeals in the D.C. Circuit stayed the application of 
    one standard and MSHA stayed two standards. The rule revises these 
    stayed provisions, revises or clarifies other provisions in the rule 
    and includes some new provisions. The provisions of the final rule are 
    expected to decrease the potential for fatalities, particularly 
    accidents which can result in multiple deaths, and to reduce the risk 
    of injuries and illnesses in underground coal mines. For the 
    convenience of the reader, MSHA has published the full text of the 
    ventilation standards for underground coal mines in this document.
    
    EFFECTIVE DATE: The final rule is effective June 10, 1996.
    
    FOR FURTHER INFORMATION CONTACT: Patricia W. Silvey, Director, Office 
    of Standards, Regulations and Variances, MSHA, phone 703/ 235-1910; fax 
    703/235-5551.
    
    SUPPLEMENTARY INFORMATION:
    
    I. Background
    
        The mining of coal underground has historically been recognized as 
    one of the more hazardous occupations in the world. It is a universally 
    recognized principle of underground coal mine safety that there must be 
    proper ventilation of the mine. Indeed, no aspect of safety in 
    underground coal mining is more fundamental than proper ventilation. A 
    basic tenet of mining safety states that ventilation must be 
    sufficient: (1) To dilute, render harmless and carry away the hazardous 
    components of mine air, such as potentially explosive methane; and (2) 
    to provide necessary levels of oxygen to the miners' working 
    environment. Ventilation safety programs are designed around this 
    philosophy. The history of mining is replete with tragic incidents 
    where one aspect or another of a necessary ventilation safety 
    protection was either not in place or not followed, with disastrous 
    results. Examples include the explosion at the Monogah mine in 1907 in 
    which 362 miners perished, the worst mining disaster in the history of 
    the United States. Other more recent examples include the Farmington 
    disaster in 1968 in which 78 miners died, the Scotia mine in 1976 where 
    26 died, Grundy No. 17 in 1981 where 13 died, Wilberg in 1984 where 27 
    died, Pyro in 1989 with 10 deaths and Southmountain in 1992 where 8 
    miners died. In 1969 and again in 1977, Congress recognized the hazards 
    of improper ventilation and established a role for the government in 
    addressing ventilation hazards. MSHA, with the cooperation of labor and 
    industry, has met with a large measure of success in reducing the 
    accidents, injuries and fatalities that have resulted from poor 
    ventilation practices. For example, explosions and fires in a 29 year 
    period from 1940 to 1968 resulted in the deaths of 491 miners. Since 
    the passage of the Federal Coal Mine Health and Safety Act of 1969, 178 
    explosion and fire related deaths have occurred. While MSHA recognizes 
    that this number is still unacceptable, the significant reduction in 
    loss of life cannot be ignored. To a great extent, the framework for 
    this success has been the implementation of effective ventilation 
    standards.
        Preventing recurrence of disasters like those of the past remains 
    the top priority of MSHA. MSHA believes that a serious commitment by 
    management, labor, and government is necessary to develop effective, 
    yet reasonable and practical regulations that protect the safety and 
    health of our nation's miners. MSHA anticipates that this rulemaking, 
    which revises portions of the comprehensive ventilation rule published 
    in 1992 (57 FR 20868, May 15, 1992) and adds new provisions, will bring 
    the coal mining industry closer to that objective.
        The comprehensive 1992 ventilation rulemaking was closely followed 
    by interested industry and labor groups, who frequently expressed 
    divergent views on approaches to resolving ventilation issues. Certain 
    commenters exercised their right to challenge the rule and the U.S. 
    Court of Appeals for the D.C. Circuit Court stayed one provision 
    relating to oxygen and carbon dioxide in the bleeder entries. MSHA held 
    a series of informational meetings around the country during which it 
    explained the application of the rule. In so doing, MSHA listened to 
    many questions about the implementation of the rule. MSHA was sensitive 
    to the views expressed at these meetings and gave serious consideration 
    to these issues. Some of these comments became the basis for portions 
    of this rulemaking. Internal discussions of MSHA's experience with the 
    implementation of the rule led MSHA to include still other issues in 
    this rulemaking. In fact, MSHA stayed the application of two additional 
    provisions in response to potential problems pointed out by interested 
    parties. These stayed provisions relate to actions following the 
    stoppage of the main mine fan with persons underground and to a 
    potential fire hazard from the enclosure of compressors in a 
    noncombustible structure. MSHA addresses these issues in the 
    rulemaking. Once MSHA decided that it was going to proceed with a 
    rulemaking to address these issues, it added other provisions to the 
    package to allow all parties an opportunity to comment where they 
    expressed the view that they had insufficient opportunity to comment on 
    the existing rule (The comprehensive rule that was published in the 
    Federal Register on May 15, 1992). The rule MSHA proposed also included 
    issues raised by parties in litigation challenging the existing rule. 
    MSHA anticipates that the final rule should resolve matters included in 
    the challenge raised by the litigation of the existing rule. Finally, 
    in an effort to address confusion that seemed to exist with certain 
    provisions of the existing ventilation rule promulgated in May of 1992, 
    MSHA either proposed clarifications to the existing rule or discussed 
    the affected provisions in the preambles to the proposed and final 
    rules in an effort to clarify them.
        The issues in the rulemaking are complex and highly technical. 
    Comments to the proposal (published on May 19, 1994, 59 FR 26536) and 
    comments following the public hearings (held in September and October 
    1994, in Price, Utah, Logan, West Virginia, and Washington, 
    Pennsylvania) were extensive. One party alone submitted over two 
    thousand pages of written comments and over 275 exhibits. Not only were 
    the safety issues involved complex, but in many cases, MSHA's task was 
    made more difficult by hearing diametrically opposed viewpoints.
    
    Major Improvements in the Final Rule
    
        The final rule provides a number of significant improvements to the 
    existing ventilation regulations. For example, the final rule provides 
    for the electronic storage of records. A major portion of the mining 
    industry has this capability at the present time through computer 
    technology at the mine site. Electronic 
    
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    record retention can reduce the cost of storage and maintenance of 
    records and provide for ease in access and transfer of information 
    without reducing the protection afforded miners. Additionally, having 
    records electronically stored can facilitate trend analysis, allowing 
    for earlier detection and correction of potential hazards.
        The final rule also requires pressure recorders or an option of the 
    use of a fan monitoring system on main mine fans at all mines. This 
    represents a major step toward monitoring the mine fans controlling the 
    ventilation at the mines and helps assure that the miners have 
    uncontaminated air at all times. The final rule also provides for 
    methane testing at the face during mining operations. This technology 
    is especially useful for taking methane tests during extended cut 
    mining operations. The methane testing evaluates air flow to the face 
    to determine that methane is sufficiently diluted, rendered harmless, 
    and carried away so as to reduce or eliminate the hazards associated 
    with methane liberated during mining operations.
        Other improvements in the rule include revisions to the three 
    stayed provisions in the existing rule. Air quality levels for oxygen 
    and carbon dioxide in bleeders are established to protect mine 
    examiners who are required to travel to determine if the bleeders are 
    functioning properly. A second stayed provision is revised to limit the 
    use of transportation equipment during the withdrawal of miners after 
    an unintentional fan stoppage. This revision to the existing rule 
    reduces the likelihood of an ignition from methane that can accumulate 
    during the fan stoppage. The third stayed provision is revised to allow 
    the option of attending rather than housing compressors in a 
    noncombustible enclosure. The hazards associated with the operation of 
    compressors in underground mines were demonstrated at the Wilberg mine 
    disaster, where 27 people lost their lives as a result of a compressor 
    fire.
        This final rule provides for an alert and alarm device to be 
    located outside of noncombustible structures housing electrical 
    installations. The alert and alarm assures that miners are made aware 
    of a problem in time to extinguish a fire or safely evacuate an area or 
    the mine as necessary for safety. Another change to the existing rule 
    involves miners or their representatives in the mine ventilation plan 
    approval process before the plan is submitted for approval. This 
    provides for the opportunity for input from those having first hand 
    knowledge in the particular mining conditions and practices that impact 
    the plan approval.
        Other safety enhancements from the existing rule include: requiring 
    the use of extendable probes to conduct methane tests at deep cuts; 
    requiring on-shift examinations on other than coal producing shifts; 
    and accepting a performance test to determine minimum dimensions at 
    certain locations in escapeways.
        Finally, the final rule clarifies existing regulations that were 
    considered vague by some parties or were misunderstood. For example, 
    the final rule provides that certified pumpers can conduct their own 
    examination rather than requiring the examination to be conducted 
    during the preshift segment of the mining operation.
        To serve the interests of the mining community, MSHA has 
    republished the full text of subpart D of 30 CFR part 75 as it will 
    read upon promulgation of this rule.
    
    II. Discussion of the Final Rule
    
    A. General Discussion
    
        In developing the final rule, MSHA has made every effort to address 
    the comments received during the rulemaking, and to develop practical 
    requirements for real safety problems. Both the costs and the benefits 
    of each standard were also considered. In addition, each standard, as 
    well as revisions and deletions, was carefully considered against the 
    statutory requirement that nothing in the final rule shall reduce the 
    protection afforded miners by an existing mandatory health or safety 
    standard. Where appropriate, MSHA has provided for a phase in period to 
    allow mine operators time to effectively plan and implement the 
    necessary changes.
        MSHA carefully analyzed the comments received and responded in many 
    instances by revising the proposed requirements. For example, unlike 
    the proposal, the final rule does not require the second level 
    countersigning of records; allows the use of nonpermissible equipment 
    when conducting an examination upon restart of a fan following 
    unintentional fan stoppages, and requires pressure recording devices or 
    an option of the use of a fan monitoring system to be used on all main 
    mine fans.
        Several commenters strongly urged MSHA to proceed in this 
    rulemaking on the issue of using air coursed through the belt entries 
    (``belt air'') to ventilate the working face. MSHA has completed its 
    consideration of the Report of the Secretary's Advisory Committee 
    Report on Belt Air and has placed the issue of using belt air to 
    ventilate the working face on the rulemaking agenda for development of 
    a proposed rule. Thus, ``belt air'' is not addressed in this 
    rulemaking.
        MSHA has also received comments and recommendations on a number of 
    other issues that are outside the scope of this rulemaking. For 
    example, much of the extensive testimony directed toward the use of 
    atmospheric monitoring systems was beyond the issues dealt with in this 
    rulemaking. Also, recommendations for the use of transparent or 
    translucent material for check curtains exceed the scope of this 
    rulemaking. The final rule, therefore, does not include these 
    recommendations.
        Commenters to the proposal frequently included a discussion of 
    various accident reports, most written by MSHA. In addition, there were 
    discussions of other documents related to specific incidents or mines, 
    such as MSHA Internal Review Reports or specific mine plans. In some 
    cases, the documents were submitted for inclusion in the record. In 
    other cases, the documents were merely referenced.
        MSHA is independently aware of the extensive history of ventilation 
    related explosions, and has considered this information. Where 
    appropriate, this information is discussed in the section-by-section 
    analysis in the preamble of this rule. MSHA is aware that accidents can 
    result from or be contributed to by the violation of one or more of the 
    existing standards. In that context, MSHA has found that the solution 
    is not necessarily to promulgate another standard. (The offender may be 
    as likely to ignore it as well.) Instead, for demonstrated 
    noncompliance with existing standards, the solution is often found in 
    increased emphasis, training, or enforcement, rather than in the 
    promulgation of additional rules.
        Several sections of the final rule deal with requirements for 
    sections and areas where mechanized mining equipment is being installed 
    or removed. These provisions, which were included in the existing 
    standard published in May 1992, were reproposed without change for the 
    purpose of receiving additional comments from all interested parties. 
    One commenter cited the William Station mine explosion as evidence of 
    the need for these requirements. Other commenters reiterated an earlier 
    objection that the standards were procedurally flawed. MSHA does not 
    agree that these provisions are procedurally flawed and notes that each 
    of these standards was reproposed and not simply restated as part of 
    this rulemaking. Comments relative to the 
    
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    technical merits of an individual standard are addressed in the 
    section-by-section portion of this preamble.
    
    Recordkeeping Requirements in the Final Rule
    
        The final rule revises the recordkeeping requirements for several 
    standards. The standards affected are Sec. 75.310, Installation of main 
    mine fans; Sec. 75.312, Main mine fan examinations and records; 
    Sec. 75.342, Methane monitors; Sec. 75.360, Preshift examination; 
    Sec. 75.362, On-shift examination; Sec. 75.363, Hazardous conditions; 
    posting, correcting and recording; Sec. 75.364, Weekly examinations; 
    and Sec. 75.370, Mine ventilation plan; contents.
        Generally, the final rule requires examiners to record the results 
    of methane tests as a percent of methane detected; records must be made 
    in a book that is secure and not susceptible to alteration, or 
    electronically in such a manner as to be secure and not susceptible to 
    alteration; and records must be countersigned by the mine foreman by 
    the end of the mine foreman's next regularly scheduled working shift. 
    These rules are intended to assure that examination results are 
    maintained and made available, and that the appropriate level of mine 
    management is made aware of conditions or problems requiring attention. 
    The revisions also help assure the integrity of records and enable mine 
    management to review the quality of the examinations. MSHA intends the 
    term ``secure and not susceptible to alteration'' when applied to 
    electronic storage to mean that the stored record cannot be modified. 
    One example of acceptable storage would be a ``write once, read many'' 
    drive.
        Numerous comments were received both supporting and opposing the 
    proposed recordkeeping requirements. MSHA reviewed and fully considered 
    each of these comments. The proposal would have required that records 
    be kept in either state-approved books or in bound books with 
    sequential machine-numbered pages. Commenters argued that under the 
    existing rule records may be falsified or altered. Commenters also 
    stated that accident investigations have demonstrated the need for 
    improved records. Other commenters asserted that the proposed 
    requirement for bound books with sequential machine-numbered pages adds 
    an economic burden for the majority of compliant operators and another 
    way should be found, ``to foil the very few who are recalcitrant.'' 
    Other commenters stated that since all records currently include dates 
    and times, machine-numbered pages are unnecessary.
        Some record books that are currently in use and acceptable under 
    the existing standards are vulnerable to misuse or manipulation. For 
    example, under the existing rule, records could be kept in a spiral 
    notebook or even a loose leaf binder. The final rule addresses this 
    issue by requiring that records be made in books that are secure and 
    not susceptible to alteration. Examples of books that are considered by 
    MSHA to be secure and not susceptible to alteration include, but are 
    not limited to, record books that are currently approved by state mine 
    safety agencies, and permanently bound books. Examples of books that 
    would not be considered books that are secure and not susceptible to 
    alteration include loose leaf binders and spiral note books.
        Several commenters advocated the use of computers for the storage 
    and retrieval of records. In support of this approach, the commenters 
    cited computer records as being highly accurate, requiring less storage 
    space and facilitating data retrieval. Other commenters expressed 
    concern for the security of records stored electronically, and offered 
    examples of breaches of security in record systems at banks and 
    national security installations as evidence to support this concern.
        Electronic storage of information and assessing it through 
    computers is more and more a common business practice generally and in 
    the mining industry. Recognizing this trend, the final rule permits the 
    use of electronically stored records provided they are secure and not 
    susceptible to alteration, are able to capture the information and 
    signatures required, and are accessible to the representative of the 
    miners and the representatives of the Secretary. Based on the 
    rulemaking record, MSHA believes that electronic records meeting these 
    criteria are practical and as reliable as traditional records.
        In the preamble to the proposal, MSHA expressed its intent to 
    require a hard copy printout of the information stored electronically 
    to be available within 1 hour of a request, and to require backing up 
    of the information within 24 hours. Commenters objected to making the 
    records available within 1 hour as being too stringent and 
    unnecessarily requiring a person to be on duty at all times. MSHA 
    agrees that the requirement would be overly burdensome and has not 
    included it in the final rule. Similarly, MSHA has not included a 
    specific requirement for backing up the computer data. The final rule 
    requires that the records be secure. This encompasses backing up the 
    data as appropriate to the conditions and electronic storage system 
    used at the mine. Upon reconsideration, MSHA has concluded that an 
    additional specific requirement would be an unnecessary burden and has 
    not included it in the rule.
        A variety of comments were received regarding the countersigning of 
    certain records by the mine foreman, and the time frame permitted for 
    countersigning. The final rule adopts the proposal that the mine 
    foreman must countersign the record by the end of the mine foreman's 
    next regularly scheduled working shift. The mine foreman is the person 
    most responsible for the day-to-day operation of the mine. It is 
    essential for the health and safety of the miners that the mine foreman 
    be fully aware of the information contained in examination reports so 
    as to be able to allocate resources to correct safety problems as they 
    develop. Allowing until the end of the mine foreman's next regularly 
    scheduled working shift to countersign the reports assures that the 
    mine foreman is aware of the results of the examination in sufficient 
    time to initiate corrective actions. In response to commenters, the 
    final rule allows a mine official equivalent to a mine foreman to 
    countersign the records.
        Some commenters suggested that the time for countersigning is 
    unnecessarily long, and that the final rule should restore a previous 
    requirement that countersigning be completed ``promptly.'' The term 
    ``promptly'' involves a level of ambiguity that is eliminated by 
    specifying the time for countersigning records. The record does not 
    show that the time set by the final rule would expose miners to safety 
    or health risks. Also, hazardous conditions are required to be 
    corrected immediately.
        Commenters suggested that the term ``mine foreman'' be replaced by 
    a ``certified person responsible for ventilation of the mine or his 
    designee.'' Another commenter suggested that the record could be 
    countersigned by the mine foreman or any other mine official 
    responsible for the day-to-day operation of the mine. Commenters stated 
    that some operations no longer use the terms ``mine foreman'', ``mine 
    manager,'' or ``superintendent.'' To provide for alternative management 
    titles, the final rule incorporates the phrase ``or equivalent mine 
    official.''
        Numerous comments were received regarding the requirement of the 
    proposal for second level countersigning by the mine superintendent, 
    mine manager, or other mine official to whom the mine foreman is 
    directly accountable within 2 scheduled 
    
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    production days thereafter. Commenters objecting to the proposal stated 
    that higher level management should be able to delegate responsibility, 
    noting that often this level of official has more than one mine to 
    oversee and may not necessarily be available within the proposed two 
    days. One commenter suggested allowing three days for second level 
    countersigning in order to recognize that such an official often has 
    numerous obligations and to allow for normal absences. Other commenters 
    simply recommended that the second level countersigning be deleted.
        Another commenter stated that some states hold the mine foreman 
    legally responsible, that the mine foreman should correct hazardous 
    conditions immediately and withdraw miners as appropriate, and that the 
    second level countersigning would add no measure of safety. One 
    commenter noted that in many cases the mine manager or superintendent 
    is not a certified individual and long periods may elapse during which 
    this person does not go underground. In these instances, the person 
    countersigning would have little or no understanding or first hand 
    knowledge of the conditions in the mine. Commenters stated that 
    countersigning by the mine foreman is adequate notification to the 
    operator of any deficiency and that the mine foreman has the necessary 
    resources and responsibility to correct any situation noted in the 
    records.
        Other commenters supported the proposal noting that second level 
    countersigning would provide an additional level of accountability. 
    These commenters also suggested that in the event of a major accident, 
    the second level countersigning requirement would be important in fully 
    assessing the contributing causes.
        MSHA has determined that countersigning by the mine foreman or 
    equivalent mine official, as specified in the final rule, provides the 
    means necessary to detect and correct developing hazards in a mine. 
    Countersigning by the mine foreman assures the necessary notification 
    to an official with the knowledge of the day-to-day operation of the 
    mine having the authority to maintain the mine in a safe operating 
    condition. Agency experience has demonstrated that higher level mine 
    officials commonly lack hands-on involvement or in-depth knowledge of 
    the specific conditions underground or how the highly detailed 
    ventilation rules impact upon those conditions. Therefore, 
    countersigning by a mine official at a higher level does not assure any 
    additional level of safety and imposes an unnecessary burden.
    
    B. Section-by-Section Discussion
    
        The following section-by-section portion of the preamble discusses 
    each provision affected. The text of the final rule is included at the 
    end of the document.
    
    Section 75.301  Definitions
    
        The final rule revises the definition of return air to permit 
    operators to designate certain air courses as return air courses for 
    the purpose of ventilating structures, areas or installations that are 
    required to be ventilated to return air courses and for ventilating 
    seals when the air in the air course will not be used to ventilate 
    working places. Thus, an operator wishing to split air off of an intake 
    for the purpose of ventilating shops, electrical installations, or for 
    other purposes, could designate the air course into which the split is 
    directed as a return provided the air in the air course would not be 
    used to ventilate working places or other locations, structures, 
    installations or areas required to be ventilated with intake air. 
    Commenters generally agreed with the change. However, one commenter 
    expressed the concern that air currents ventilating electrical 
    installations could be coursed to the conveyor belt entry before being 
    coursed to a redesignated return air course, and thus not vented 
    directly to a return. The commenter expressed the opinion that because 
    the air is not vented directly to a return under this scenario, the 
    rule would not permit this practice. MSHA does not agree with the 
    commenter's interpretation and the final rule, consistent with 
    Sec. 75.340, permits this practice.
        MSHA does not anticipate that operators will need to redesignate 
    air courses on a routine basis. When questions arise as to the need to 
    redesignate an intake as a return, the operator should contact the 
    local MSHA office. In order that all interested persons are made aware 
    when an air course is redesignated, the final rule requires in 
    Sec. 75.372, Mine ventilation map, that such redesignated air courses 
    be shown on the mine's ventilation map.
    
    Section 75.310  Installation of Main Mine Fans
    
        The main mine fans serve a vital role in providing ventilation to 
    prevent methane accumulations and possible explosions as well as 
    providing miners with a healthful working environment. Section 75.310 
    is primarily directed at protecting the main mine fans from fires and 
    damage in the event of an underground explosion so that necessary 
    ventilation can be maintained. Monitoring of the fans to assure that 
    they are operating properly is an element of this protection. The final 
    rule for Sec. 75.310 revises paragraphs (a) and (c) of the existing 
    rule. The revisions address: (1) automatic signals for fan stoppage, 
    (2) pressure recording devices, and (3) main mine fan monitoring 
    systems.
        Paragraph (a)(3) of Sec. 75.310, like the proposal, requires each 
    main mine fan to be equipped with an automatic device that gives a 
    signal at the mine when the fan either slows or stops. The existing 
    rule does not specify where the signal is to be given. Commenters 
    supported the proposal stating that a signal alarming at a location 
    away from the mine site would rely on overland communication lines to 
    transmit the signal, with the person receiving the signal then 
    notifying the mine. These overland communication lines are subject to 
    weather and other potential sources of damage, which could result in a 
    disruption of the communication. Other commenters objected to the 
    proposal, however, stating that the ability of a mine operator to 
    consolidate monitoring of several mines at one single location is a 
    very efficient and cost-effective practice and should not be 
    arbitrarily prohibited. Further, they stated that there would be 
    absolutely no delay in contacting the miners from this central location 
    should a fan malfunction occur. For clarity and for increased safety, 
    the final rule requires that the signal be given at the mine. MSHA 
    believes that in the case of a fan stoppage, this will assure more 
    timely notice to miners, and hence, a more effective safety response. 
    The requirement that the signal be given at a surface location at the 
    mine does not preclude the signal from also being given elsewhere, such 
    as at a central office, as long as it is given at the mine.
        Paragraph (a)(3) of Sec. 75.310 requires that a responsible person, 
    designated by the operator, shall always be at a surface location at 
    the mine where the signal can be seen or heard while anyone is 
    underground. In addition, the responsible person must be provided with 
    two-way communication with working sections and with other established 
    locations where persons are normally assigned to work. Commenters 
    supported the proposal stating that the changes provide clarification 
    and specificity. Other commenters agreed with the proposed concept of 
    two-way communication but felt that the wording, ``established 
    locations where persons are normally assigned to work'' is ambiguous 
    and subject to misinterpretation. Some commenters 
    
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    objected to the proposed requirement stating that (1) it is redundant 
    of Sec. 75.1600 Communications; (2) properly the subject of a separate 
    rulemaking under Sec. 75.1600 or; (3) it is vague, ambiguous, or 
    subjective. Section 75.1600 only requires two-way communication between 
    the surface and working sections and does not identify that this 
    communication must be provided to a location where a person can see or 
    hear the fan alarm signal. Commenters suggested that the requirement be 
    revised to more specifically quantify locations where persons are 
    normally assigned to work. MSHA recognizes that, as proposed, the 
    standard might result in misinterpretation and the final rule has been 
    reworded to read, ``* * * two-way communication with working sections 
    and work stations where person(s) are routinely assigned to work for 
    the majority of a shift.''
        Some, but not all, outby areas where two-way communication would be 
    required by the final rule include; shops, attended belt transfer 
    points, attended rail car loading points, and attended underground coal 
    storage bins and hoppers. It is not intended that this communications 
    capability be provided in areas where secondary roof support is being 
    installed or where rock dust is being applied, or at unattended 
    underground pumps, or in areas such as return air courses, bleeder 
    entries and conveyor belt haulageways other than at belt transfer 
    points. The requirement that two-way communication be provided to work 
    stations where persons are routinely assigned to work for the majority 
    of a shift is intended to help assure that these persons receive prompt 
    notification of fan stoppages. Because these work stations are off the 
    working section, a lack of communication capabilities could result in 
    delays in notification and therefore delays in egress from the mine.
        Paragraph (a)(4) of the existing rule requires that main mine fans 
    be equipped with a pressure recording device or with a main mine fan 
    monitoring system but exempts from this requirement mines permitted to 
    shut down main mine fans under Sec. 75.311.
        The final rule eliminates this exemption and requires that all main 
    mine fans be equipped with a pressure recording device or a main mine 
    fan monitoring device. For mines not currently required to have such a 
    device, MSHA has provided for a 1 year phase in period to allow mine 
    operators time to effectively plan and implement the necessary changes. 
    One commenter suggested that all main mine fans at all mines be 
    required to operate continually and further suggested that all main 
    mine fans be equipped with pressure recording devices and main mine fan 
    monitoring systems. In support of this suggestion, the commenter stated 
    that continuous fan pressure recording devices would have a positive 
    impact on safety at these operations. Such devices will provide 
    necessary information to operators and miners at operations affected by 
    this change. MSHA has not included one commenter's suggestion that main 
    mine fan monitoring systems be required for all main mine fans. While 
    MSHA supports and encourages the use of this advanced technology the 
    Agency does not believe that it is appropriate to mandate it for all 
    mines because daily fan examinations coupled with pressure recording 
    devices have proved to be adequate over the years. Also, MSHA does not 
    adopt a suggestion that main mine fans at all mines be required to 
    operate continuously.
        Paragraph (a)(4) of the final rule requires that when a pressure 
    monitoring device is used in lieu of a pressure recording device, it 
    must produce a continuous graph or chart of the fan pressure. A hard 
    copy of the continuous graph or chart must be printed at regular 
    intervals of not more than 7 days. This provision permits the use of 
    relatively recent advances in technology for monitoring main mine fan 
    pressure provided a continuous record of the fan pressure is provided. 
    In the proposal, MSHA specifically solicited comments as to an 
    appropriate polling frequency that would provide a record that is 
    substantially continuous. In response to this request, one commenter 
    proposed that a polling frequency of two seconds is necessary to take 
    full advantage of available technology. This commenter stated that 
    continuously means constant or unbroken and that a continuous record 
    should require a polling frequency of not greater than 2 seconds. 
    Another commenter, an instrument manufacturer, suggested that a one 
    minute sampling interval is definitely feasible. Main mine fan 
    monitoring, when used, is often part of a more comprehensive mine-wide 
    atmospheric monitoring system (AMS), and to require that the fan be 
    polled every two seconds could delay the polling of other important 
    sensors. Additionally, because these pressure monitoring devices are 
    intended to be used in lieu of the traditional circular pressure 
    recorder they must provide a substantially equivalent record. 
    Experience by MSHA engineers following mine explosions and during more 
    routine ventilation survey work has shown that the accuracy to which a 
    7-day, circular recording chart of the type normally used can be read 
    is on the order of several minutes. MSHA would expect that the polling 
    frequency for a pressure recording device used in lieu of a pressure 
    recorder would be no more than one (1) minute.
        MSHA received a number of comments in response to the proposed 
    requirement in paragraph (a)(4) that when a pressure recording device 
    other than a circular pressure recorder is used, a hard copy of the 
    continuous graph or chart be generated at not more than 7-day 
    intervals. Comments ranged from requiring daily printouts to not 
    requiring any printout except when requested by an Authorized 
    Representative of the Secretary. In response to these comments, the 
    final rule retains the requirement for a hard copy of the continuous 
    graph or chart be generated at not more than 7-day intervals. In light 
    of MSHA's stated position to permit records of examinations to be 
    stored electronically, the final rule permits the record of main mine 
    fan pressure to be stored electronically provided the record is secure 
    and not susceptible to alteration.
        Paragraph (c) of Sec. 75.310 specifies requirements for main mine 
    fan monitoring systems if used under Sec. 75.312. Commenters suggested 
    that the requirements were repetitive, confusing, and would discourage 
    mine operators from using monitoring systems which could provide more 
    protection. MSHA believes that the requirements in paragraph (c) are 
    necessary to effectively monitor a fan, particularly when these systems 
    are used in lieu of daily fan examinations.
        Paragraph (c)(3) of Sec. 75.310 of the proposal would have required 
    that main mine fan monitoring systems provide, on demand, a printout of 
    the monitored parameters, including the mine ventilating pressure. 
    Several commenters objected to the requirement that a printout be 
    provided ``on demand.'' As interpreted by these commenters, this 
    standard would require that the operator provide a printout at any time 
    it is requested. As explained in the preamble to the proposal, ``* * * 
    the monitoring system would be required to have the capability of 
    providing (emphasis added), on demand, a printout of the information 
    being monitored. This capability is intended to facilitate the review 
    of the information by mine management required in Sec. 75.312(b).'' The 
    commenters misinterpreted the purpose for the standard. MSHA 
    recognizes, 
    
    [[Page 9769]]
    however, the merits of being able to obtain a printout within a 
    reasonable period of time. Therefore, the final rule requires that a 
    main mine fan monitoring system used to satisfy the requirements of 
    Sec. 75.312 provide a printout of the monitored parameters, including 
    the mine ventilating pressure, within a reasonable period, not to 
    exceed the end of the next scheduled shift during which miners are 
    underground.
        Paragraph (c)(5) of Sec. 75.310 requires that two-way communication 
    be provided between a surface location at the mine where the signals 
    from the fan monitoring system can be seen or heard and working 
    sections and other established locations where persons are normally 
    assigned to work for the majority of the shift. Except for minor 
    editorial changes, this requirement is the same as the proposal. 
    Comments on this proposal were the same as comments on proposed 
    paragraph (a)(3). Several commenters supported the proposal stating 
    that the changes provide clarification and specificity. Other 
    commenters agreed with the proposed concept of two-way communication 
    but felt that the wording, ``established locations where persons are 
    normally assigned to work'' is ambiguous and subject to 
    misinterpretation. Some commenters objected to the proposed requirement 
    stating that (1) it is redundant of Sec. 75.1600 Communications; (2) 
    properly the subject of a separate rulemaking under Sec. 75.1600 or; 
    (3) it is vague, ambiguous, or subjective. Section 75.1600 only 
    requires two-way communication between the surface and working sections 
    and does not identify that this communication must be provided to a 
    location where a person can see or hear the fan alarm signal. 
    Commenters suggested that the requirement be revised to more 
    specifically quantify locations where persons are normally assigned to 
    work. MSHA recognizes that, as proposed, the standard might result in 
    misinterpretation and the final rule has reworded the proposal to read, 
    ``* * * two-way communication with working sections and work stations 
    where person(s) are routinely assigned to work for the majority of a 
    shift.''
        Some, but not all, outby areas where two-way communication would be 
    required by the final rule include; shops, attended belt transfer 
    points, attended rail car loading points, and attended underground coal 
    storage bins and hoppers. It is not intended that this communications 
    capability be provided in areas where secondary roof support is being 
    installed or where rock dust is being applied, or at unattended 
    underground pumps, or in areas such as return air courses, bleeder 
    entries and conveyor belt haulageways other than at belt transfer 
    points. The requirement that two-way communication be provided to work 
    stations where persons are routinely assigned to work for the majority 
    of a shift is intended to help assure that these persons receive prompt 
    notification of fan stoppages or other problems with the fan that might 
    require withdrawal of miners. Because these work stations are off the 
    working section, a lack of communication capabilities could result in 
    delays in notification and therefore delays in egress from the mine.
    
    Section 75.311  Main Mine Fan Operation
    
        The main mine fan provides the pressure that causes air to move 
    through the mine to dilute and carry away explosive and toxic gases, 
    dusts and fumes. As such it is the most important part of the 
    ventilation system. Section 75.311 requires fans to be continuously 
    operated to provide constant ventilation to underground areas and 
    specifies precautions for planned fan stoppages. It also addresses the 
    repair of main mine fans, monitoring of fan signal devices on the 
    surface, and protection against fires around fans and intake air 
    openings.
        The final rule revises paragraph (d) of Sec. 75.311, which 
    addresses the notification of mine officials of any unusual variance in 
    mine ventilation pressure and requires the prompt repair of electrical 
    or mechanical deficiencies. The final rule requires immediate 
    notification and the prompt institution of corrective action or 
    repairs.
        Commenters suggested deletion of the word ``unusual'' maintaining 
    that this term makes the requirement vague and subject to different 
    interpretations. These commenters suggested substituting the phrase, 
    ``that could materially affect the safety and health of persons in the 
    mine'' to describe the type of pressure variance that would require 
    action. In making this recommendation, the commenters cited similar 
    language in existing Sec. 75.324(a)(1) that, according to the 
    commenters, is understood throughout the coal mining community. Section 
    75.324(a)(1) concerns alterations of the main ventilation air current 
    or any split of the main air current. The final rule does not adopt 
    this recommendation. Minor fluctuations in fan operating pressure are 
    normal; however, unusual changes can be indications of changes in fan 
    operation or changes underground, such as roof falls or loss of 
    ventilation controls, that require prompt attention and corrective 
    action. In addition, MSHA has 25 years of experience with the phrase 
    ``unusual variances in mine ventilation pressure'' and is unaware of 
    significant difficulties with this terminology.
        Commenters questioned what constitutes an ``electrical or 
    mechanical deficiency'' for the purposes of Sec. 75.311. The purpose of 
    the standard is to assure that a problem with main mine fans is 
    corrected promptly and that the proper persons are notified that the 
    problem exists. The types of electrical or mechanical deficiencies 
    requiring action under paragraph (d) are those that can interfere with 
    mine ventilation. In addition, MSHA has 25 years of experience with the 
    phrase ``electrical and mechanical deficiencies'' and is, again, 
    unaware of any significant difficulties with the use of this 
    terminology during this time frame.
        Commenters also addressed the proposal that the ``mine 
    superintendent, assistant mine superintendent, or mine foreman'' be 
    notified immediately when an unusual variance in mine ventilation 
    pressure is observed, or when an electrical or mechanical deficiency in 
    a main mine fan is detected. The final rule does not retain the mine 
    superintendent or the assistant mine superintendent as mine officials 
    to be notified. Commenters stated that this provision provides a 
    measure of safety to the miners by requiring that specific mine 
    managers be notified of possible main mine fan problems, while the 
    existing standard specifies that such a situation must be investigated. 
    Other commenters, however, suggested that the persons identified for 
    notification under the proposal may not be the most qualified to handle 
    the problem. They also indicated that the notification requirement 
    could unnecessarily delay appropriate action by other responsible 
    persons. The commenters further stated that the mine superintendent or 
    assistant mine superintendent may not be at the mine and that a 
    certified person would be in charge who should be permitted to take the 
    appropriate action. The proposed requirement that certain mine managers 
    be notified immediately was not intended to require that these 
    individuals personally take the necessary actions to respond to the 
    problem with the main mine fan. Neither was it intended that they be 
    notified of such a problem, to the exclusion of all others. The 
    objective of the rule is to assure that the appropriate actions are 
    taken as soon as possible. Additionally, notification of specified mine 
    officials is intended to assure that those persons who are responsible 
    for the mine are aware of the problem. The 
    
    [[Page 9770]]
    final rule, therefore, retains the requirement that certain mine 
    managers be notified of any unusual variance in the mine ventilation 
    pressure or if an electrical or mechanical deficiency of a main mine 
    fan is detected.
        The final rule does, however, delete reference to notification of 
    the mine superintendent or assistant mine superintendent. As discussed 
    in relation to the countersigning of records, the mine superintendent 
    is quite often not a certified person and is only periodically present 
    at the mine. In addition, consistent with other sections of the final 
    rule and recognizing that the term mine foreman is not used at some 
    mines, the final rule requires that if an unusual variance in the mine 
    ventilation pressure is observed, or if an electrical or mechanical 
    deficiency of a main mine fan is detected, the mine foreman or 
    equivalent mine official, or in the absence of the mine foreman or 
    equivalent mine official, a designated certified person acting for the 
    mine foreman or equivalent mine official shall be notified immediately. 
    As with the proposal, the final rule requires that appropriate action 
    or repairs shall be instituted promptly. It is not intended that the 
    appropriate action or repairs be delayed until the mine foreman or 
    equivalent mine official is notified.
        During a series of informational meetings held by MSHA following 
    publication of the existing rule, questions arose concerning the 
    operation of back-up fans. For informational purposes, the preamble to 
    the proposal included a detailed discussion of questions about the 
    operation of back-up fans under the ventilation regulations and 
    solicited comments. MSHA did not propose any rule changes, nor does the 
    final rule contain specific provisions for back-up fans. When a back-up 
    fan operates in place of the main mine fan, the back-up fan is 
    considered to be a main mine fan and all subpart D requirements for 
    main mine fans are applicable.
    
    Section 75.312  Main Mine Fan Examinations and Records
    
        Proper operation of main mine fans is critical to mine ventilation 
    and the prevention of methane accumulations and possibly methane 
    explosions. Recognizing the importance of the main mine fan, 
    Sec. 75.312 requires that each main mine fan be examined at least once 
    each day that the fan operates unless the fan is continuously monitored 
    with a main mine fan monitoring system. Through daily examinations or 
    continuous monitoring of critical parameters, the operator can 
    determine if problems with the fan are developing and correct these 
    problems before ventilation is affected.
        The final rule removes existing paragraph (g)(2), revises existing 
    paragraphs (a), (b)(1), (c), (d), (g)(1) and (h), redesignates existing 
    paragraph (f) as (f)(1), and adds new paragraphs (f)(2) and (g)(2). 
    Paragraph (a) of the final rule, like the existing rule, requires daily 
    examination of main mine fans unless a fan monitoring system is used. 
    In addition, paragraph (a) specifies that an examination of the main 
    mine fan is not required on days when no person goes underground. An 
    examination of the fan, however, is required prior to anyone entering 
    the mine. The purpose of this examination, as stated in paragraph (a), 
    is to assure the electrical and mechanical reliability of the fan.
        When a fan monitoring system is used, the final rule requires a 
    daily review of the data from the monitoring system to be made, except 
    on days when no person goes underground. A review of the data from the 
    monitoring system must be completed, however, prior to anyone entering 
    the mine.
        Fan examinations or review of fan monitoring system data are 
    required to be performed by a trained person designated by the 
    operator.
        Commenters questioned the use of the term ``assure'' in paragraph 
    (a) when referring to the electrical and mechanical reliability of main 
    mine fans. MSHA uses the term ``assure'' in this context as defined in 
    Webster's Third New International Dictionary, Unabridged, 1993 edition, 
    to mean, ``to make safe, to give confidence to.'' The sense of this 
    definition is consistent with the intended purpose of the examination. 
    The term does not mean to ``guarantee'' safety, as suggested by one 
    commenter.
        Commenters suggested that the final rule require the examination of 
    main mine fans for proper operation be conducted by an individual 
    trained as part of the mine operator's training plan required by MSHA's 
    comprehensive training regulation in part 48 of 30 CFR. Other 
    commenters understood the proposal to require training of fan examiners 
    under part 48, and objected to such a requirement. These commenters 
    suggested that the person conducting the fan examination be one who has 
    received training through experience or has been trained by an 
    experienced person, or by the fan manufacturer. The final rule does not 
    require fan examiners to be trained as part of the operator's part 48 
    training plan. Instead, the final rule specifies that fan examiners 
    must be trained sufficiently to have the skill and knowledge to 
    ascertain whether the fan is in proper working order, mechanically and 
    electrically.
        Paragraph (a) requires a daily physical examination of the main 
    mine fan, unless a fan monitoring system is used. If a fan monitoring 
    system is used, paragraph (b) requires a weekly physical examination of 
    the main mine fan, a weekly test of the monitoring system, and a daily 
    review of the main mine fan monitoring data. Commenters suggested that 
    even if a main mine fan is equipped with a monitoring system, the fan 
    should still be subject to daily physical examinations because a fan 
    monitoring system is not capable of disclosing all conditions that a 
    physical inspection could disclose. The final rule does not adopt this 
    suggestion. A weekly physical examination of the fan and a test of the 
    monitoring system coupled with a daily review of the monitoring data 
    provides reasonable assurance that a mine fan is operating reliably. 
    Commenters suggested that the proposed requirement of paragraph (b)(1) 
    requiring a daily review of main mine fan monitoring system data is 
    unnecessary and redundant. These commenters suggested that the system 
    need only be capable of producing a printout because the systems would 
    automatically alarm anytime an electrical or mechanical deficiency 
    exists. Requiring a daily review of the monitoring system data, 
    according to these commenters, could discourage the use of improved 
    technology. Other commenters noted that operators currently using fan 
    monitoring systems conduct a daily review of the data at the present 
    time and that the requirements to review the data would provide an 
    additional measure of safety for the miners. MSHA believes that a daily 
    review of data from fan monitoring systems is needed to assure that 
    mine management is made aware of any operational changes or trends in 
    monitored parameters. Main mine fans provide the source for mine 
    ventilation and, therefore, are critical to miners' safety. As 
    discussed earlier, these daily reviews of data are designed to 
    complement the physical examinations of the fan.
        The final rule adopts the requirements of proposed paragraphs 
    (b)(1)(ii) (A) and (B) and requires that when a fan monitoring system 
    is used as provided under paragraph (a), a trained person designated by 
    the operator must test the system for proper operation at least every 7 
    days. Commenters objected that it is redundant because a fan monitoring 
    system is capable of monitoring itself and can automatically provide a 
    warning when a fan malfunction occurs. These commenters also stated 
    that if the 
    
    [[Page 9771]]
    system is continuously operated, the system is self-tested for proper 
    operation several times a minute and that the 7-day test is 
    unnecessary. The commenters suggested that the 7-day test only be 
    conducted if the fan monitoring system is not continuously operated. 
    For continuously operating fans an examination of the fan should more 
    appropriately be conducted monthly, according to these commenters. 
    Requiring more frequent checks the commenters maintain would discourage 
    the use of fan monitoring systems.
        The final rule does not adopt these suggestions. While MSHA 
    encourages the use of fan monitoring systems, excessive reliance on the 
    self-monitoring features of these systems is incompatible with the 
    importance of reliable operation of main mine fans. MSHA does not 
    anticipate that the final rules for examination requirements will 
    discourage the use of fan monitoring systems. Main mine fans without a 
    monitoring system are required to be examined daily, while fans with 
    monitoring systems are required to be examined every seven days.
        Paragraphs (c) and (d) of Sec. 75.312 of the final rule continue in 
    effect the requirements that tests of the automatic fan signal device 
    and automatic closing doors, when these doors are required, be 
    conducted at intervals not to exceed 31 days. The specified means of 
    testing these devices and doors is by stopping the fan. The proposal 
    would have permitted an alternative test not involving stopping the fan 
    if the alternative method provided the same level of assurance that the 
    signal device or door would function as intended during fan stoppages. 
    Two commenters favored the proposal and suggested that there is no need 
    to approve alternate means of testing fan signal devices in the mine 
    ventilation plan. These commenters expressed the opinion that each 
    authorized representative should be capable of ascertaining the 
    validity of the alternative method. The commenters did not make a 
    similar suggestion relative to the alternative means provision proposed 
    in paragraph (d) for automatic closing doors. Another commenter opposed 
    the use of alternative tests stating that it would be premature to 
    adopt a provision for an alternative test to stopping the fan when such 
    a test has not as yet been developed. MSHA has reconsidered the 
    proposal and the final rule continues to require that the tests of fan 
    signal devices and automatic closing doors be conducted by stopping the 
    fan. Should an operator develop an alternative method that provides the 
    same level of protection as stopping the fan, the petition for 
    modification process is available for an operator to obtain approval.
        Paragraphs (c) and (d) permit underground power to remain energized 
    during fan signal and automatic closing door testing, notwithstanding 
    the requirements of Sec. 75.311. If the fan is not restarted within 15 
    minutes, the final rule requires that underground power be deenergized 
    and no one is permitted to enter any underground portion of the mine 
    until the fan is restarted and an examination is conducted. 
    Additionally, paragraphs (c) and (d) require that only persons 
    necessary to evaluate the effect of the fan stoppage or restart, or to 
    perform maintenance or repair work that cannot otherwise be done while 
    the fan is operating, are permitted underground.
        Some commenters objected to limiting the persons who can be 
    underground during fan signal and closing door tests. Other commenters 
    objected to anyone being permitted underground during the stoppage of a 
    fan to conduct the required tests. These commenters expressed the 
    opinion that all necessary work can be performed with the fan operating 
    and therefore, when a fan is shut down to test the fan signal device or 
    the automatic closing doors no one should be underground.
        Some work, such as working immediately inby a blowing fan, could 
    place workers at risk by exposing them to extreme temperatures, effects 
    of the high velocity air stream, or excessive noise levels when the fan 
    is operating. In addition, repair work within a shaft can more safely 
    be done when a fan is stopped. The rule, therefore, retains the 
    exception that permits persons underground during intentional fan 
    stoppages to evaluate the effect of the fan stoppage or restart, or to 
    perform maintenance or repair work that cannot otherwise be done while 
    the fan is operating.
        Paragraphs (c) and (d) of the final rule are reworded to clarify 
    that during the required tests, power circuits may remain energized 
    only if no person is underground. Therefore, if an operator elects to 
    evaluate the effect of the fan stoppage or restart, or to perform 
    maintenance or repair work that cannot otherwise be done while the fan 
    is operating, simultaneous with the tests required, power circuits must 
    be deenergized in accordance with Sec. 75.311(b)(3). Additionally, in 
    accordance with Sec. 75.311(b)(2), all mechanized equipment must be 
    shut off.
        Paragraph (f)(1) of the final rule retains the longstanding 
    requirement that the person performing main mine fan examinations 
    certify by initials and date at the fan or another location specified 
    by the operator that the examinations were made. Each certification is 
    required to identify the main mine fan that was examined. When daily 
    fan examinations are conducted, daily certification is required. When a 
    main mine fan monitoring system is used and fan examinations are 
    conducted at 7 day intervals, certification is required each time the 
    fan is examined.
        One commenter offered suggested wording that would eliminate the 
    option of certifying that the examination was completed at a location 
    other than the fan being examined. This suggestion has not been adopted 
    and the final rule retains the flexibility for certifications to be 
    made away from the fan.
        Paragraph (f)(2) of the final rule requires that when a main mine 
    fan monitoring system is used, a daily printout of the system's data 
    must be certified to indicate that the daily review was completed. 
    While some commenters generally agreed with this requirement other 
    commenters suggested that an alternative should be provided for systems 
    which are continuously operated and supervised. In such cases, the 
    commenters suggested that immediate notification of the mine foreman 
    when a deficiency arises would be appropriate, together with 
    maintaining the internal records of data gathered by the systems for 
    one year.
        The suggested alternative is not included in the final rule. MSHA 
    believes that documentation that monitoring system data is being 
    reviewed is necessary to provide reasonable assurance that mine 
    management is aware, on a timely basis, of the operating condition of 
    the fan being monitored. However, to reduce the burden of this 
    requirement, the final rule in paragraph (f)(2) does permit the 
    electronic certification of the review of the data generated by a fan 
    monitoring system. As with electronically kept records, the rule would 
    require that the electronic certification include handwritten initials 
    and dates. A discussion of comments concerning the use of computers to 
    maintain records can be found in the General Discussion of this 
    preamble.
        Paragraph (g)(1) of Sec. 75.312 requires that by the end of the 
    shift on which the examination is made, persons making main mine fan 
    examinations must record all uncorrected defects found during the 
    examination that may affect the operation of the fan. The rule also 
    specifies that records be maintained in a book that is secure and not 
    susceptible 
    
    [[Page 9772]]
    to alteration, or electronically in such a manner as to be secure and 
    not susceptible to alteration. The proposal would have required all 
    defects found during the main mine fan examination that may affect the 
    operation of the fan to be recorded whether corrected or uncorrected.
        Some commenters objected to recording defects that ``may'' affect 
    the operation of the main mine fan, and suggested only defects that do 
    affect the operation of the main mine fan and that are not corrected by 
    the end of the shift, need to be recorded.
        Some commenters asserted that a record of ``all'' defects should be 
    required in order to identify recurring problems that may lead to 
    bigger problems. These commenters interpreted the proposal to require 
    such a record. The final rule is intended to address problems found 
    during fan examinations that may indicate more serious defects and 
    ultimately lead to a fan failure and that cannot be corrected by the 
    end of the shift. The objective is to record defects of a nature and 
    seriousness that could result in a fan failure, but not to record 
    defects that are so minor that it would be unreasonable to expect fan 
    failure to result. Another commenter stated that recording all defects 
    that may affect fan operation would result in excessive paperwork of 
    little value. This commenter also suggested that if mine ventilation 
    does become ineffective, the workers are to be withdrawn from the mine. 
    MSHA is sensitive to concerns about recordkeeping. Therefore, the final 
    rule requires that all uncorrected defects which are found during the 
    examination that may affect fan operation be recorded. In this manner, 
    miners on the oncoming shift are aware of problems with the fan that 
    potentially could impact underground ventilation.
        Commenters supported the use of electronic media as a substitute 
    for specific types of record books. Commenters pointed out that almost 
    all such systems incorporate recordkeeping functions and that 
    significant variances from the norm are easily noted. They concluded 
    that the computer monitoring systems provide superior protection for 
    the miners. The final rule permits, in paragraph (g)(1), the use of 
    electronically stored records for main mine fan examinations provided 
    the records are secure, are able to capture the information and 
    signatures required, and are accessible to the representative of the 
    miners and the representatives of the Secretary.
        As with other records required by this rule, paragraphs (g)(2) and 
    (g)(3) require that records required by Sec. 75.312 must be made in 
    books that are secure and not susceptible to alteration, or 
    electronically in such a manner as to be secure and not susceptible to 
    alteration. A detailed discussion of record books and the use of 
    computers to maintain records can be found in the General Discussion of 
    this preamble.
        Paragraph (g)(2) of the existing rule requires that at mines 
    permitted to shut down main mine fans under Sec. 75.311, if a pressure 
    recording device is not used, a record shall be made, in a book 
    maintained for that purpose, of the time and fan pressure immediately 
    before the fan is stopped, and after the fan is restarted and the fan 
    pressure stabilizes. The final rule does not retain this requirement in 
    light of the new requirement of Sec. 75.310(a)(4) that all main mine 
    fans be provided with a pressure recording device or an option of the 
    use of a fan monitoring system. This new requirement eliminates the 
    need for an additional record of the time and fan pressure made 
    immediately before the fan is stopped and after the fan is restarted 
    and the fan pressure stabilizes. This information is obtained from the 
    pressure recording chart, which records the pressure continuously and 
    automatically, thus maintaining the protection afforded the miners.
        Paragraph (h) of the final rule requires that the records required 
    by Sec. 75.312 be maintained at a surface location at the mine for one 
    year and be made available for inspection by authorized representatives 
    of the Secretary and the representative of miners. Comments were 
    generally favorable on this proposal. A discussion of comments 
    concerning the use of computers to maintain records can be found in the 
    General Discussion of this preamble.
        As with the other provisions of the final rule allowing electronic 
    certification or recordkeeping, sufficient protections have been 
    included so that there is no reduction in protection from the existing 
    standards.
    
    Section 75.313  Main Mine Fan Stoppage With Persons Underground
    
        Section 75.313 was stayed by MSHA as explained in the introductory 
    section of this preamble. Generally, this standard is concerned with 
    protecting miners from the danger introduced when the main mine fan 
    stops, such as when there is a loss of power. Under these 
    circumstances, mine ventilation is interrupted, permitting gases such 
    as methane to accumulate. These conditions can lead to an explosion 
    ignited by electric circuits or the operation of equipment.
        Paragraph (a)(3) of the final rule requires that if a main mine fan 
    stops, everyone shall be withdrawn from the working sections and from 
    areas where mechanized mining equipment is being installed or removed. 
    The language of the final rule is identical to the wording of stayed 
    Sec. 75.313 (a)(3). An in-depth discussion of provisions concerning the 
    installation and removal of mechanized mining equipment is presented in 
    the General Discussion section of this preamble.
        The final rule revises paragraphs (c)(2), (c)(3), (d)(1)(i) and, 
    (d)(1)(ii) of the stayed standard. Paragraphs (c)(2) and (c)(3) require 
    that when a main mine fan stops with persons underground, the 
    underground electric power circuits shall be deenergized and mechanized 
    equipment shall be shut off. These rules further recognize an exception 
    to facilitate miners' evacuation from the mine. The exception 
    temporarily permits some circuits to remain energized and some 
    mechanized equipment to not be shut off, provided these circuits and 
    mechanized equipment are necessary to withdraw persons from the mine 
    and are located in areas where methane is not likely to migrate to or 
    accumulate. These circuits must be deenergized and the mechanized 
    equipment must be shut off as persons are withdrawn. The final rule 
    differs from the stayed standard by limiting the exception permitting 
    the use of these circuits or equipment to areas where methane is not 
    likely to migrate to or accumulate.
        Paragraph (d)(1)(i) requires that when a fan stoppage lasts for 
    more than 15 minutes a preshift-type examination must be conducted 
    before persons other than designated examiners, are permitted to enter 
    any underground area of the mine. Examiners are permitted to re-enter 
    the underground area of the mine from which miners have been withdrawn 
    only after the fan has operated for at least 15 minutes unless a longer 
    period of time is specified in the mine ventilation plan. Paragraph 
    (d)(1)(ii) requires that when a fan stoppage lasts for more than 15 
    minutes, underground power circuits are not to be energized and 
    nonpermissible mechanized equipment is not to be started until a 
    preshift-type examination is conducted, except that designated 
    certified examiners may use nonpermissible transportation equipment in 
    intake airways to facilitate the conduct of the required examination.
        Some commenters suggested that actions following fan stoppages are 
    best handled on a mine-by-mine basis through a plan approval process. 
    Along 
    
    [[Page 9773]]
    these lines, commenters suggested that the fan stoppage plan approval 
    process previously used by MSHA should be used with only minor 
    modification to assure that plans do not become standardized, that is, 
    model the rule on a past standard with criteria for approval of fan 
    stoppage plans. Other commenters, while supporting the concept of fan 
    stoppage plans, proposed to tie the submission and approval of such 
    plans to total mine ventilation surveys and computer simulations 
    conducted by the operator every three months. According to one 
    commenter the data provided by these surveys would be used to determine 
    the adequacy of a fan stoppage plan.
        The final rule does not adopt the suggestions of the commenters for 
    mine fan stoppage plans. One objective in this rulemaking is to reduce 
    the need for paperwork, such as plans, where reasonable, uniform 
    requirements can be developed. The final rule establishes the general 
    requirement that after a fan stoppage lasting more than 15 minutes, 
    mine power and equipment is to be shut down. However, experience shows 
    that using transportation equipment to facilitate mine evacuation is 
    often necessary, provided this is done where gas is not likely to 
    accumulate, and circuits are deenergized on the way out of the mine.
        Some commenters suggested that the requirements in paragraphs 
    (c)(2) and (c)(3) limiting the use of transportation equipment to areas 
    and haulageways ``where methane is not likely to migrate to or 
    accumulate'' are inconsistent with certain state laws. As support for 
    this assertion, the commenters gave the example of the state of 
    Illinois' requirements for evacuating mines following an interruption 
    in ventilation, which does not expressly recognize limited use of power 
    and equipment to facilitate evacuation. State mine safety laws, 
    including Illinois', are similar to the final rule provisions for 
    evacuation after a mine fan stoppage. As a general rule, state mine 
    safety regulations that are more stringent than MSHA standards are not 
    considered to be in conflict with federal regulations, and the more 
    stringent safety requirement applies. In this case, if the Illinois 
    regulation would not permit temporary use of power and equipment to 
    facilitate evacuation, then the state law would not be inconsistent 
    with MSHA.
        Several commenters objected to the wording, ``where methane is not 
    likely to migrate to or accumulate,'' in paragraphs (c)(2) and (c)(3), 
    as being vague. Other commenters stated that the rule's requirement was 
    simply good practice that would be heeded by prudent mine managers. 
    MSHA agrees that the terms and objectives of the final rule are 
    understood in the mining community, and believes that the determination 
    of whether methane may migrate from adjacent areas and enter travelways 
    and haulageways used by miners during withdrawal should be made on a 
    mine-by-mine basis. Therefore, the final rule retains the exception 
    that power circuits may remain energized and mechanized equipment may 
    be operated only if located in areas where methane is not likely to 
    migrate to or accumulate.
        Some commenters stated that history does not support the need for 
    the requirements of paragraphs (c)(2) and (c)(3). Mine fan stoppages 
    unquestionably result in the existence of unventilated areas and may 
    result in highly hazardous methane accumulations. Although there have 
    been a limited number of ignitions/explosions directly attributable to 
    the operation of transportation equipment during a fan stoppage, the 
    true measure of the potential hazard addressed by this standard can be 
    seen in the ignitions and explosions that were the result of the 
    operation of transportation equipment in unventilated areas. Examples 
    of such types of accidents include: The 1972 Itmann No. 3 explosion, in 
    which 5 miners died; the 1976 Scotia Mine explosion, in which 15 miners 
    died; the 1982 Virginia Pocahontas No. 6 Mine explosion in which 1 
    miner was injured; the 1983 McClure No. 1 Mine explosion, in which 7 
    miners died; the 1983 Homer City Mine explosion in which a mine 
    examiner was killed; the 1983 Greenwich Collieries No. 1 Mine explosion 
    in which 3 miners were killed and 4 miners were injured and; the 1993 
    explosion at the Buck Mountain No. 2 Mine in which 3 miners were 
    injured. Given this history of explosions, it would not be prudent to 
    permit electric circuits to remain energized and mechanized equipment 
    to be operated in areas or haulageways where methane is likely to 
    migrate to or accumulate during a fan stoppage.
        One commenter stated that the in-mine test necessary to determine 
    the likelihood of methane migration could only be done with the fan 
    stopped. The commenter questioned whether miners would be permitted 
    underground during the tests. To the extent the tests require the main 
    mine fan to be turned off, persons would be allowed underground to 
    evaluate the effect of the fan stoppage or restart.
        Paragraphs (d)(1)(i) and (ii) address safety precautions for 
    reentering the mine after ventilation is restored. Key objectives of 
    these standards are the protection of the examiners and the safety of 
    miners returning to work.
        As proposed, paragraph (d)(1)(i) would have required that when a 
    fan stoppage lasts for more than 15 minutes a preshift- type 
    examination be conducted covering the requirements of Sec. 75.360(b) 
    through (e) before persons, other than designated examiners, enter any 
    underground area of the mine. Commenters suggested that to provide the 
    level of protection desired, a complete preshift examination, including 
    the certification and recordkeeping requirements of Sec. 75.360(f) 
    through (g), should be required. Commenters pointed to the need for 
    miners reentering evacuated areas to be able to determine if the area 
    had been examined and urged that the final rule require the examiner to 
    certify by initial, date and time the areas examined.
        MSHA agrees that clear notice to miners about which areas have been 
    examined is necessary and consistent with the objectives of the rule. 
    The final rule, therefore, adopts the proposal. A record of the 
    hazardous conditions found by examiners is required under Sec. 75.363 
    of the final rule. This record serves the purpose of providing mine 
    management with the information necessary relative to the existence and 
    correction of hazardous conditions in the mine. The final rule 
    incorporates these requirements by specifying that the scope of the 
    examination be conducted as described in Sec. 75.360(b) through (e).
        Under paragraph (d)(1)(i) no one other than designated certified 
    examiners would re-enter any underground area of the mine until the 
    entire examination is completed. Commenters suggested that paragraph 
    (d)(1)(i) be revised to permit partial examinations following fan 
    stoppages and restarts under certain conditions. Under this suggested 
    approach, the examination would focus on the effectiveness of the 
    mine's ventilation system and methane accumulations in travelways, work 
    places or other areas where miners will work following the interruption 
    of ventilation. One commenter further suggested that an exception to 
    this examination be provided for noncoal producing shifts, where 
    persons are to work in the shaft, slope, drift, or on the immediate 
    shaft or slope bottom area. The commenter suggested the examination 
    following a fan stoppage could be limited to this area.
        The final rule does not adopt this approach. Limiting the scope of 
    examinations following an interruption in mine ventilation to general 
    
    [[Page 9774]]
    ventilation effectiveness and methane accumulation would not focus on 
    likely areas of concern. For example, no examination for hazards would 
    be required, and no air measurements to determine if the air is moving 
    in its proper direction and at its normal volume would be required. As 
    to the area of the mine required to be examined, only those places 
    where miners will return to work and the route of travel used to reach 
    these places must be examined. Thus, the final rule is sufficiently 
    flexible to meet the commenter's concerns about non- coal producing 
    shifts.
        A question arose during public meetings as to the meaning of the 
    term on-coming shift in Sec. 75.360 when applied to Sec. 75.313. For 
    the purposes of Sec. 75.313(d)(1)(i) and (ii) the term ``persons on the 
    on-coming shift'' is interpreted as meaning persons on the shift on 
    which the fan is restarted. If a fan outage extends from one shift into 
    another, a preshift examination as required by Sec. 75.360 must be 
    completed before any person, except certified examiners designated to 
    conduct the examination, enters the mine.
        Commenters also suggested that the final rule specify a minimum 
    time for the fan to run before examiners re-enter the mine so that 
    examiners are not unduly exposed to danger. Several commenters observed 
    that this is a general practice in the industry.
        MSHA agrees that an important measure of safety is gained by 
    allowing the mine fan to run sufficiently long to begin reventilating 
    the mine before anyone enters. The final rule, therefore, provides 
    designated certified examiners shall enter the underground area of the 
    mine from which miners have been withdrawn only after the fan has 
    operated for at least 15 minutes unless a longer period of time is 
    specified in the approved mine ventilation plan. The 15 minute 
    provision will permit re- ventilation of entries in which examiners 
    will travel to take place and the examiners will then be traveling into 
    the mine in fresh air.
        Proposed paragraph (d)(1)(ii) would have required that when a fan 
    stoppage lasts more than 15 minutes underground power circuits are not 
    to be energized and nonpermissible equipment is not to be started until 
    a preshift-type examination is completed. Commenters objected to the 
    proposal for various reasons. One commenter suggested that before power 
    is permitted to be energized a complete ventilation survey should be 
    required. Other commenters focused on the practical considerations 
    involved in conducting examinations and urged that use of 
    nonpermissible equipment for the transportation of examiners be 
    permitted.
        As revised, paragraph (d)(1)(i) requires that the main fan when 
    restarted run for at least 15 minutes so that restoration of mine 
    ventilation is underway before anyone enters the mine. Once this is 
    accomplished, electrical circuits in shafts and slopes can be energized 
    safely as these areas are the first places to be reventilated by fresh 
    air. Accordingly, the final rule permits these circuits to be re-
    energized after the mine fan has run for at least 15 minutes.
        The final rule also permits examiners to use nonpermissible 
    equipment for transportation during the examination. The proposal would 
    have prohibited this practice. Some commenters supported the proposed 
    prohibition citing two mining accidents involving nonpermissible 
    equipment in unventilated areas. Other commenters objected to the 
    proposal not to allow the use of nonpermissible equipment to facilitate 
    examinations following the restart of a main mine fan. These commenters 
    stated that travelways and equipment roadways can be examined and 
    tested for the presence of methane, the results of the examination 
    called out, and typical nonpermissible transportation equipment placed 
    into operation to expedite the examination of the mine.
        After considering all of the comments, MSHA has revised the 
    proposal and the final rule permits the use of nonpermissible 
    transportation equipment, in intake airways, to facilitate making the 
    examinations after an interruption in mine ventilation. Using 
    nonpermissible equipment in this fashion, in nonventilated areas, has 
    been a demonstrably safe practice for many years in the industry. In 
    addition, the requirement of running the fan for 15 minutes before 
    reentering the mine, together with keeping the transportation equipment 
    in the intake airways where the main ventilating current travels first, 
    provides the desired level of safety.
        Under proposed paragraph (d)(2), if ventilation was restored to the 
    mine before miners reached the surface, all miners would have been 
    required to continue traveling to the surface. As proposed, designated 
    certified examiners would have been permitted to remain underground for 
    the purpose of beginning the required examination. The final rule does 
    not adopt the proposal and retains the language of the existing 
    standard.
        While supporting the requirement that miners continue to the 
    surface after a fan is restarted, some commenters objected to 
    permitting certified persons to remain underground. These commenters 
    also took the position that once a fan has been off for more than 15 
    minutes, all efforts to restart the fan should be suspended, unless it 
    is known that it is safe to restart the fan. Other commenters expressed 
    significantly different views on both issues. A number of commenters 
    supported restarting the fan as soon as possible because the longer it 
    is off, the greater the potential hazard. MSHA concurs with this 
    reasoning and the final rule adopts this approach.
        On the issue of requiring the evacuation to continue once it has 
    begun until the fan is restarted, even when ventilation is restored, a 
    number of commenters objected that such a requirement would result in 
    unnecessary delays and may result in additional safety risks. One 
    commenter stated that the proposal would not allow for the variables 
    that exist from mine to mine. Several commenters suggested that if the 
    operator has reason to believe that the time frame of the fan stoppage 
    would be less than the travel time or equivalent, the dangers of 
    traveling outby into possible pockets of dangerous gas buildup (or 
    other travel hazards) far outweigh the dangers of staying on the 
    section in intake air back from the face. This would also allow the 
    miners to remain on the section and proceed to the working places after 
    the fan has restarted and the working places have been examined by a 
    certified person.
        MSHA disagrees with this position. In some mines, the time to 
    travel from the outside to the working sections can approach 1 hour. 
    Following the approach suggested, miners would remain on the section in 
    an unventilated mine for up to 1 hour. If at the end of this time 
    ventilation is still not restored, it is unclear whether the miners 
    then proceed to the surface, traveling through the same area the 
    commenter suggested might be hazardous some 45 minutes before.
        The commenters stated further that, ``Forcing miners to walk out of 
    the mine could take hours and unnecessarily delay the restoration of 
    ventilation and resumption of operations.'' While there may be 
    instances where the time required to withdraw miners is increased, the 
    requirements in paragraphs (c)(2) and (c)(3) have no impact on the 
    restoration of ventilation. In fact, MSHA's position is that 
    ventilation should be restored as soon as possible following a fan 
    stoppage.
        Lastly, a number of commenters suggested that when ventilation is 
    restored during evacuation, miners should be permitted to remain where 
    
    [[Page 9775]]
    they are and return to working areas after an examination of inby areas 
    is completed. These commenters stated that no additional measure of 
    safety is gained by requiring miners to continue to the surface if 
    ventilation has been restored and the area in which the miners are 
    located is free of hazards. MSHA agrees and has retained the language 
    of the existing rule. By retaining the existing language, the general 
    practice of miners stopping their evacuation and waiting for examiners 
    to complete their work will continue. Under this approach, miners 
    remain in a safe location while ventilation of the mine is restored. 
    They do not return to any area of the mine until it has been determined 
    to be safe. The final rule does not prevent mine operators from having 
    miners continue to the surface if they so choose. Regardless of whether 
    miners remain where they are or continue to the surface, paragraph 
    (d)(1)(i) of the final rule requires that the fan operate for at least 
    15 minutes before the examination of the areas from which miners have 
    withdrawn is examined.
    
    Section 75.320  Air Quality Detectors and Measurement Devices
    
        Section 75.320 establishes the standards for the devices relied 
    upon to test for the presence of methane and other dangerous gases that 
    can accumulate in a mine. It generally requires that these devices be 
    approved and maintained in permissible and proper operating condition.
        The final rule adds a new paragraph (e). It requires that 
    maintenance of instruments required by paragraphs (a) through (d) of 
    Sec. 75.320 to detect and measure air quality be done by a trained 
    person. The final rule does not include the proposal that before each 
    shift care shall be taken to assure the permissible condition of the 
    air quality detectors and other measurement devices to be used during 
    the shift. MSHA has concluded that this requirement would have been 
    redundant with paragraph (a) and is unnecessary. The final rule permits 
    an operator to send instruments to a repair facility or to the 
    manufacturer for regular servicing. Commenters at the informational 
    meetings and in later discussions on the existing rule stated that 
    maintenance by trained persons should be specified and that requiring 
    only that air quality detectors and other measurement devices be 
    maintained in permissible condition would not be sufficient. They 
    stated that without a requirement for maintenance to be done by a 
    trained person, similar to that which existed in the previous standard, 
    a person with less than the necessary understanding of the instrument 
    and the permissibility requirements might be assigned the task.
        Several commenters suggested that the requirements of paragraph (e) 
    are redundant with general requirements found elsewhere in the 
    standards and are unnecessary. Other commenters felt that the current 
    performance standard is adequate, but that the meaning of ``assure'' is 
    unclear. Still other commenters indicated that the assurance of 
    permissibility is properly the responsibility of the user. One 
    commenter noted that the instruments are intrinsically safe and that 
    the manufacturer's instructions are sufficient. MSHA agrees that the 
    general requirement under paragraph (a), together with requiring 
    trained persons, is adequate.
        Another commenter suggested that a formal written maintenance 
    program be required. Under this suggestion, the program would be 
    subject to MSHA approval and would include records of all maintenance 
    and calibrations to be made by the end of the shift. This commenter 
    also suggested that existing paragraph (a) be revised to provide for 
    more frequent calibration by inserting the phrase ``* * * or more often 
    if necessary * * *.'' This suggestion has not been adopted since 
    compliance with the proper operating and permissibility provisions of 
    paragraph (a) would result in more frequent calibration, if necessary. 
    MSHA notes that under the previous standard, there was no written 
    maintenance program required nor were records required. MSHA believes 
    that experience under both the previous and existing standards 
    demonstrates that, with the addition of paragraph (e), maintenance and 
    calibration is appropriately addressed in the final rule and safety is 
    not reduced.
        Several commenters agreed with the proposal for a ``trained'' 
    person to maintain air quality detectors and measurement devices. These 
    commenters suggested that the trained person be defined as a person 
    designated by the operator who has received training through experience 
    in maintenance of the instrument, has been trained by an experienced 
    person, or one who has received training by or through the instrument 
    manufacturer. MSHA has not adopted this suggestion since the operator 
    should have some flexibility as to the mode of training. The 
    requirement that the person performing the maintenance must be trained 
    is intended to mean that the person be capable of doing the required 
    maintenance, not that they receive a specific course of instruction in 
    what to do.
        Commenters suggested that maintenance and calibration requirements 
    should parallel those proposed under Sec. 75.342 for machine-mounted 
    methane monitors. They suggested that, because the detectors and 
    monitors perform similar functions, the requirements should be similar. 
    The final rule does not adopt this suggestion. The methane monitoring 
    instruments under this standard and those governed by Sec. 75.342 are 
    subject to different mining conditions. For example, machine-mounted 
    monitors must be calibrated and maintained underground, on the 
    equipment on which they are installed and on working sections. This 
    calibration must also be scheduled within production timetables. 
    Handheld detectors and measurement devices, however, are removed from 
    the mine and are maintained and calibrated in surface environments. 
    Calibration and maintenance of handheld detectors is usually done 
    during shifts when the instruments are rotated out of service. Thus 
    machine-mounted monitors are calibrated and maintained under more 
    strenuous conditions than handheld detectors.
        One commenter suggested that written records of all maintenance and 
    calibration should be required. The commenter further suggested that: 
    Each operator submit a written maintenance program to MSHA for approval 
    and provide a copy to the miner's representative; the written program 
    specify training to be provided; records be completed by the person 
    performing maintenance and be countersigned by the mine foreman within 
    24 hours; and that records be maintained for one year and be made 
    available to MSHA and the representative of the miners. These 
    additional requirements were not included in the proposal and are not 
    adopted in the final rule. The requirements contained in the final rule 
    adequately address and are appropriately related to the concerns 
    relative to maintenance, calibration, permissibility, and the general 
    condition of air quality detectors and measurement devices.
    
    Section 75.321  Air Quality
    
        The primary function of a mine ventilation system is twofold, to 
    remove hazardous gases such as methane, and to provide miners with an 
    respirable environment in areas where they are required to work or 
    travel. As discussed in the introductory section of this preamble, 
    Sec. 75.321 of the existing standard was stayed by the United States 
    Court of Appeals for the District of Columbia Circuit as it pertains to 
    bleeder entries. The final rule, in 
    
    [[Page 9776]]
    Sec. 75.321, addresses acceptable levels of oxygen and carbon dioxide 
    in areas of a mine, including areas of a bleeder entry, where persons 
    are required to work or travel.
        Paragraph (a)(1) continues a basic air quality requirement that has 
    been in place since 1970 that air in areas where persons work or travel 
    contain at least 19.5 percent oxygen and not more than 0.5 percent 
    carbon dioxide, and the volume and velocity of the air current in these 
    areas be sufficient to dilute, render harmless, and carry away 
    flammable, explosive, noxious, and harmful gases, dusts, smoke, and 
    fumes. Paragraph (a)(2) applies the same requirement for oxygen, 19.5 
    percent, for the air in areas of bleeder entries and worked-out areas 
    where persons work or travel. The final rule does not require the 
    carbon dioxide level of 0.5 percent to be applied to bleeder entries 
    and worked-out areas. Rather paragraph (a)(2) requires that the carbon 
    dioxide levels in the air in bleeder entries and worked-out areas where 
    persons work or travel not exceed 0.5 percent time-weighted average 
    (TWA) and 3.0 percent short-term exposure limit (STEL).
        MSHA interpreted former Sec. 75.301 to require at least 19.5 
    percent oxygen and no greater than 0.5 percent carbon dioxide in 
    bleeder systems where persons work or travel. It was MSHA's intent that 
    existing Sec. 75.321 would necessitate compliance with these levels 
    where persons would be exposed in bleeder entries and in worked-out 
    areas. However, the application of this provision to bleeders and 
    worked-out areas was stayed by the United States Court of Appeals 
    pending the outcome of litigation addressing the promulgation of the 
    existing rule. MSHA continues to believe that providing necessary air 
    quality is essential to protect miners and examiners whenever they work 
    or travel in bleeder entries and worked-out areas. Therefore, the final 
    rule includes a new provision specifying that the air in bleeder 
    entries and worked-out areas where persons work or travel contain at 
    least 19.5 percent oxygen, and that carbon dioxide not exceed 0.5 
    percent TWA and 3.0 percent STEL. A TWA is the time-weighted average 
    concentration for a normal 8-hour workday and a 40-hour workweek. A 
    STEL is the maximum time-weighted average concentration to which miners 
    can be exposed for a continuous period of up to 15 minutes. Commenters 
    noted an error in the preamble to the proposal with respect to the time 
    an individual can be exposed to concentrations between the TWA and the 
    STEL. MSHA intends to apply TWA and STEL levels in a manner consistent 
    with the Air Quality rulemaking. The levels for carbon dioxide in the 
    final rule for areas where persons work or travel in bleeder entries 
    and worked-out areas are identical to the levels contained in MSHA's 
    proposed Air Quality standards for coal and metal and nonmetal mines 
    and the 1992 Threshold Limit Values (TLVs) as specified by the American 
    Conference of Governmental Industrial Hygienists (ACGIH).
        Some commenters suggested that other changes be included in the 
    final rule. First, they recommended that the permissible minimum oxygen 
    level for bleeders and worked-out areas be lowered from 19.5 percent to 
    18 percent. Second, they suggested that the requirements that apply to 
    bleeders and worked-out areas be expanded to include airways associated 
    with bleederless mining areas. The rationale given for this second 
    recommendation was that the conditions in these airways are similar to 
    bleeders. In light of the ongoing Air Quality rulemaking, MSHA is not 
    at this time clarifying existing Air Quality standards except those for 
    worked-out areas and bleeder entries.
        Commenters for the most part agreed with the change relative to 
    carbon dioxide although one commenter indicated that there was no need 
    for any standard. Bleeder entries and worked-out areas are required to 
    be traveled or evaluated at least weekly. Generally, this is done by a 
    person traveling alone who is often required to be in the bleeder 
    entries or worked-out areas for an extended period. The purpose of this 
    standard is to protect miners, not to regulate air quality where 
    persons are not exposed. Therefore, if examinations are performed 
    remotely or if persons making the examination can otherwise remain in 
    air that meets the requirements of the standard, oxygen and carbon 
    dioxide levels at bleeder connectors and bleeder evaluation points 
    would not have to meet the concentrations required by the final rule.
        According to the National Institute for Occupational Safety and 
    Health (NIOSH) of the U.S. Department of Health and Human Services 
    (NIOSH Respirator Decision Logic, May 1987), 19.5 percent oxygen 
    provides an adequate amount of oxygen for most work assignments and 
    incorporates a safety factor. Also according to NIOSH, the safety 
    factor is needed because oxygen-deficient atmospheres offer little 
    warning of danger. In the NIOSH publication, ``A Guide to Safety in 
    Confined Spaces,'' (page 4), a chart is presented that indicates that 
    19.5 percent oxygen is the minimum level for safe entry into an area, 
    and that at a level of 16 percent, judgement and breathing are 
    impaired. The American National Standards Institute (ANSI), in ANSI 
    Z88.2-1992, ``American National Standard for Respiratory Protection'' 
    recognizes that at 16 percent oxygen there is an impairment in the 
    ability to think and pay attention, and a reduction in coordination. 
    ANSI recognizes that at 19 percent oxygen there are some adverse 
    physiological effects.
        The need for regulating the oxygen level where persons work or 
    travel in bleeder entries is illustrated by two mining accidents. One 
    of these accidents resulted in the death of a mine examiner and the 
    second resulted in the near death of two individuals, one of whom was a 
    mine examiner. Mine examiners are, through training and experience, the 
    individuals best able to identify the hazards associated with 
    irrespirable atmospheres. The first accident occurred at the Arclar 
    Mine in Equality, Illinois in 1989. Prior to implementation of the 
    existing standard, a mine examiner entered a worked-out area that was 
    posted with a danger sign and was asphyxiated. Under the existing 
    regulation, ventilation or sealing of this area, rather than posting, 
    would be required. Because the area was not sealed, the existing 
    regulation would require the area to be examined during the weekly 
    examination. The final rule would require that the route of travel for 
    the examiner contain at least 19.5 percent oxygen. Had the final rule 
    been in place when the examiner entered the worked-out area, the 
    accident may have been avoided.
        The second accident, although not in a bleeder entry or worked-out 
    area, is illustrative of what can happen when individuals, including 
    mine examiners, are subjected to oxygen deficient air. In 1983 at the 
    Bird No. 3 Mine in Riverside, Pennsylvania, an assistant mine foreman, 
    a certified person, entered the mine for the purpose of conducting an 
    examination. After traveling approximately 1100 feet, the examiner 
    became dizzy, noticed that his flame safety lamp had extinguished and 
    withdrew approximately 200 feet where he sat down and apparently became 
    unconscious. A second individual upon entering the area in search of 
    the examiner also became dizzy but was able to withdraw to a location 
    that was not oxygen deficient. When the mine examiner regained 
    consciousness, his cap lamp battery had discharged and he traveled in 
    total darkness until he encountered a mine rescue team. Air samples 
    collected in the area where the mine examiner first became dizzy 
    
    [[Page 9777]]
    indicated an oxygen level of about 16.8 percent, while other samples 
    collected nearby indicated oxygen concentrations of nearly 20 percent.
        Because mine examiners are required to work or travel in areas 
    where oxygen-deficient air could occur without warning, and they 
    normally travel and work alone, there must be a requirement that 
    provides them the protection necessary for the performance of their 
    duties under these conditions. It is important that the level for 
    oxygen be established above that identified as resulting in impaired 
    judgement because it is essential that individuals traveling in these 
    areas remain highly alert. The hazards that can exist in bleeder 
    entries and worked-out areas include elevated methane levels, poor 
    footing, loose and unstable roof, and water accumulations. For this 
    reason, the final rule adopts a minimum level of oxygen of 19.5 percent 
    as recommended by NIOSH.
        MSHA is also concerned with the effects of other gases often found 
    in bleeder entries. Section 75.322 of the existing regulation limits 
    the concentration of noxious or poisonous gases to the current (1971) 
    TLV's as adopted and applied by the ACGIH. Section 75.322 specifically 
    excludes carbon dioxide since it is covered by Sec. 75.321. However, so 
    the mining public will clearly understand the application of the 
    regulation, the final rule establishes a separate standard for carbon 
    dioxide levels for areas where persons work or travel in bleeder 
    entries and worked-out areas. The levels set by the final rule, 0.5 
    percent TWA and 3.0 percent STEL, when considered in conjunction with 
    the requirements of Sec. 75.322 and the requirement for oxygen, will 
    provide persons working or traveling in these areas with a safe and 
    healthful working environment. MSHA recognizes that the effects of 
    carbon dioxide are both chronic and acute and, therefore, sets both a 
    TWA and a STEL. NIOSH, in recommending a standard for carbon dioxide, 
    also recognized this and recommended a similar approach. The NIOSH 
    recommendation, made in a Criteria Document published in 1976, proposed 
    a TWA concentration of 1.0 percent and a ceiling value of 3.0 percent 
    not to exceed 10 minutes. In making this recommendation, NIOSH 
    recognized that there are additive stress effects of increased carbon 
    dioxide concentrations and exercise. As support for this, the NIOSH 
    document cites research that showed that healthy, trained subjects 
    exposed to 2.8 to 5.2 percent carbon dioxide at maximum exercise levels 
    experienced respiratory difficulty, impaired vision, severe headache, 
    and mental confusion; three subjects collapsed.
        During rulemaking on the proposed air quality standard, NIOSH 
    recommended a 0.5 percent TWA and a 3.0 percent STEL. NIOSH made a 
    similar recommendation to the Occupational Safety and Health 
    Administration during that Agency's permissible exposure limit 
    rulemaking. Given the work environment in bleeder entries and worked-
    out areas, as described earlier, MSHA believes that the regulatory 
    approach to bleeders and worked-out areas provided by the final rule is 
    necessary and appropriate. In addition to examiners, other miners may 
    be required to work in the bleeder entries and worked-out areas, 
    performing duties such as installing roof support, pumping water, 
    recovering materials or adjusting ventilation. The levels established 
    in the final rule would provide these miners with the necessary 
    protection.
    
    Section 75.323  Actions for Excessive Methane
    
        Section 75.323 establishes the actions that must be taken when 
    methane reaches certain levels. Methane is the most dangerous gas 
    encountered by miners working underground. When the level of methane 
    reaches 5.0 percent it is explosive. Section 75.323 generally 
    establishes action levels below this lower explosive limit to permit 
    appropriate actions to be taken by mine operators in order to prevent 
    an explosion.
        The final rule adopts the proposal for Sec. 75.323. In doing so, it 
    revises paragraphs (b)(1)(ii), (c)(1), and (d)(2)(i) of the existing 
    standard. The rule clarifies that corrective actions at specified 
    methane levels must be taken ``at once'' and provides that actions for 
    excessive methane include areas where mechanized mining equipment is 
    being installed or removed. MSHA believes that final rule Sec. 75.323 
    increases the protection afforded by the existing standard.
        Initially, the need for clarification was raised during 
    informational meetings and subsequent discussions after publication of 
    the existing rule. As discussed below, the final rule retains the 
    language of the proposal which is identical to the wording of the 
    previous standard.
        Some commenters indicated that delays in remedial actions to reduce 
    methane were being experienced at some mines. These commenters 
    attributed delays to the deletion of the phrase ``at once'' in the 
    existing standard. These commenters also suggested that the phrase ``at 
    once'' conveys the proper sense of urgency to correct the condition. 
    Other commenters stated that the addition of the phrase ``at once'' 
    does nothing to improve health or safety. MSHA has included the phrase 
    in the final rule for clarity.
        Methane poses a significant hazard to miners when it is permitted 
    to accumulate without corrective action being taken quickly. MSHA has 
    always intended that corrective changes be made at once. The final rule 
    revises paragraphs (b)(1)(ii), (c)(1) and (d)(2)(i) to require that 
    these changes be made ``at once,'' the phrase used in former 
    Secs. 75.308 and 75.309.
        Some commenters stated that the proposal, if literally enforced, 
    would necessitate changes to be made before the cause or source of the 
    increase in methane can be investigated. Other commenters stated that 
    approvals must be obtained for many ventilation changes and that some 
    changes require extended periods of time to complete. Operators may 
    take those actions necessary to abate imminent dangers or hazardous 
    conditions, or to safeguard persons and equipment. A part of this 
    action would be a determination of the cause of the problem. MSHA knows 
    of no case where an operator has been prohibited from a necessary 
    correction for a methane problem pending a plan approval. However, in 
    cases where intentional changes are made which could materially affect 
    the safety and health of miners, approval is required before resumption 
    of normal work if the changes affect the information approved in the 
    mine ventilation plan. MSHA recognizes that some ventilation changes 
    take time to accomplish and interprets the phrase ``at once'' as 
    meaning that the work of making the necessary change to reduce methane 
    levels begins immediately.
        One commenter questioned how the phrase ``at once'' would apply to 
    a methane feeder which is encountered despite an appropriate and well 
    thought out ventilation change. MSHA recognizes that methane feeders 
    may be encountered unexpectedly. As long as a mine operators takes 
    action as required by the standard, they will be in compliance.
        One commenter suggested that some MSHA personnel were improperly 
    interpreting methane excursions above 1.0 percent to be violations of 
    the standard. The commenter seemed to suggest the regulations should 
    provide that the actions specified in Sec. 75.323 for excessive methane 
    do not apply to concentrations detected on machine-mounted methane 
    monitors. Other commenters indicated that the standard requires 
    unnecessary ventilation 
    
    [[Page 9778]]
    changes in response to instantaneous increases caused by excessive 
    methane liberation. MSHA recognizes that instantaneous methane monitor 
    readings for machine mounted monitors may occasionally reach or exceed 
    1.0 percent. Usually, these are short-lived and the monitor reading 
    quickly falls below 1.0 percent, even before the machine operator can 
    react. However, consistent monitor readings of 1.0 percent or more 
    indicate a problem and should cause appropriate changes and 
    adjustments. Repeated short duration increases above 1.0 per cent 
    should also be cause for concern and may necessitate changes or 
    adjustments to ventilation.
        With respect to paragraphs (b)(1), (b)(2), and (c)(1) some 
    commenters stated that the mere presence of methane does not constitute 
    a violation of a mandatory health and safety standard. MSHA agrees. In 
    this context, one commenter suggested replacing the word ``present'' 
    with ``detected.'' The commenter continued that an operator cannot 
    possibly correct a methane problem until it has been detected, that the 
    rule should reflect realistic expectations, and that the current term 
    ``present'' is meaningless. MSHA agrees that a methane problem cannot 
    be corrected unless it has been detected and that the mere presence of 
    methane does not constitute a violation. Only the failure to properly 
    respond once being made aware of the presence of methane in excess of 
    allowable levels is a violation. The standard requires that an operator 
    properly conduct an examination; and if methane over 1.0 percent or 1.5 
    percent is found, as applicable, corrective action must be taken at 
    once.
        When 1.0 percent or more methane is present in a working place, an 
    intake air course, or an area where mechanized mining equipment is 
    being installed or removed, paragraph (b)(1)(i) of the final rule 
    requires all electrical, diesel, and battery- powered equipment in the 
    affected working place, intake air course, or other area, except for 
    intrinsically safe AMS, to be deenergized or shut off. Deenergizing or 
    shutting off of this equipment protects miners by preventing this 
    equipment from providing ignition sources.
        One commenter suggested that non-intrinsically safe AMS equipment 
    should be permitted to run under battery power when 1.0 percent or more 
    methane is encountered. The commenter stated that the benefit derived 
    through the system's operation outweighs the hazard of the non-
    intrinsically safe system. The commenter continued that since the 
    batteries will deplete quickly, little hazard would result, or in the 
    alternative, each battery outstation could be monitored for methane and 
    automatically trip at some set methane level. The final rule does not 
    include this suggestion. Where excessive methane concentrations 
    necessitate that power be deenergized, information from continued 
    operation of the non-intrinsically safe system would not outweigh the 
    potential ignition hazard. To permit operation of a non- intrinsically 
    safe system in areas known to contain excessive levels of methane would 
    be a departure from accepted, effective, and long standing safety 
    practice.
        Several commenters objected to the requirement in paragraph 
    (b)(1)(iii) that prohibits any work in the affected area until the 
    methane is reduced to less than 1.0 percent. Commenters questioned 
    whether the standard would prohibit an operator from taking steps to 
    reduce the methane. The language must be given a reasonable 
    interpretation and should be considered in context of the preceding 
    requirement in paragraph (ii) that ``changes or adjustments shall be 
    made at once * * * ''
        These requirements are virtually identical to those found in the 
    previous standard which was in effect for over 20 years. MSHA is 
    unaware of any instance where an operator was prohibited from 
    correcting methane problems by such an application of the standard.
        Some commenters suggested adding a phrase to paragraph (b)(1)(iii) 
    to read, ``No work other than removal of the accumulation shall be 
    permitted * * * '' Similarly, MSHA believes that the suggested change 
    is unnecessary and has not adopted it. MSHA experience indicates that 
    the rule is well understood and has been properly applied.
        Other commenters thought that the standard, as proposed, would 
    cause hasty, ill-advised changes to be made and would prohibit an 
    investigation into the cause or source of the methane problem which 
    could result in phased-in corrections. MSHA agrees that operators 
    should seek long term solutions and should fully investigate the cause 
    or source of methane accumulations. Investigation and long term 
    corrections are not prohibited by the rule. However, the final rule 
    does require that certain actions be undertaken at once to correct the 
    short term or acute safety hazards resulting from accumulations of 
    methane.
        If 1.5 percent or more of methane is present in a working place, an 
    intake air course, or an area where mechanized mining equipment is 
    being installed or removed, paragraph (b)(2) of the final rule requires 
    persons to be withdrawn from the affected area. The presence of methane 
    in these areas can pose a significant risk to miners and therefore 
    their withdrawal from the affected area is essential to their safety. 
    Paragraph (b)(2) also requires that all electric power to equipment in 
    affected areas be disconnected at the power source. This prevents 
    accidental energization of equipment and removes power from cables and 
    circuits which may also be ignition sources. No other work is permitted 
    in the affected area until the concentration of methane is less than 
    1.0 percent. A conforming change is also made to paragraph (b)(2) by 
    adding ``mechanized'' before mining equipment for consistency with 
    other provisions of the rule.
        Comments were received which objected to the (b)(2)(ii) requirement 
    that except for intrinsically safe AMS, electrically powered equipment 
    in the affected area shall be disconnected at the power source. Some 
    commenters suggested that this equipment should be simply 
    ``deenergized.'' These commenters stated that there was no need to 
    disconnect the power source, that this could require belt drives, 
    pumps, etc. to be physically disconnected where permanent connections 
    have been made, which could result in a major unnecessary operation. 
    MSHA has not adopted this suggested revision. MSHA issues numerous 
    citations and orders for damaged power cables, trailing cables, and 
    splices where the conductors are badly damaged or exposed. Each of 
    these citations and orders represents the presence of a potential 
    ignition source. Power cables would remain energized under these 
    conditions as would be the case if the commenters' suggestion were 
    adopted.
        There are several aspects of Sec. 75.323 which were not proposed 
    for revision, but for which comments were received. Comments were 
    received relative to the 1.0 percent action level in intake air 
    courses. Commenters contended that Congress established an immutable 
    methane limitation of 0.25 percent in intakes. Commenters stated that 
    because Congress had expressly limited intakes passing openings to 
    abandoned areas to 0.25 percent methane, that implicitly, all intakes 
    were limited to 0.25 percent methane. However, the commenter then 
    suggested adopting an intake action level for methane of 0.5 percent. 
    MSHA notes that the methane levels were not proposed for revision and 
    are not being revised under the final rule. The commenters, however, 
    should refer to a discussion of this issue included in the 
    
    [[Page 9779]]
    preamble to the existing rule dated May 15, 1992.
        If 1.5 percent or more methane is present in return air, paragraph 
    (d)(2)(i) would require changes or adjustments be made ``at once'' to 
    the ventilation system to reduce the concentration of methane. Because 
    of the hazards presented by accumulations of methane, MSHA believes 
    that changes or adjustments should be made immediately and be made 
    independent of the mine ventilation plan in the interest of safety. 
    MSHA recognizes that some changes take time to complete. If operators 
    begin ``at once'' to make the necessary changes and adjustments, they 
    will be in compliance with the standard.
        MSHA received comments relative to Sec. 75.323 which, although were 
    outside the scope of the rulemaking, demonstrate an incorrect 
    understanding of the existing rule. The limitations on methane content 
    and the associated actions required when excessive methane is 
    encountered are important components of a safety program to protect 
    underground miners. Therefore, several of these comments will be 
    addressed so that the mining community will better understand these 
    standards.
        First, one commenter objected to the existing requirements in 
    Sec. 75.323(d). The commenter incorrectly stated that paragraph (d) 
    permits normal operations with 1.5 percent methane in working places. 
    Methane limits in working places and intake air courses is limited by 
    Sec. 75.323(b). Paragraph (b) specifies actions if 1.0 percent methane 
    is present, and withdrawal if 1.5 percent is present. Similarly, 
    Sec. 75.323(c) limits methane between the last working place on a 
    working section and where that split of air meets another split of air 
    to 1.0 percent and requires withdrawal at 1.5 percent. Paragraph (d) 
    modifies the requirement for that portion of the return split outby the 
    section loading point and has no effect on methane either in working 
    places or between the last working place and the point in the return 
    opposite the loading point.
        One commenter indicated a preference for the language used in a 
    previous MSHA regulation, Sec. 75.308-1. The previous standard 
    restricted the changes or adjustments to increasing the quantity or 
    improving the distribution of air in the affected working place to an 
    extent sufficient to reduce and maintain the methane to less than 1.0 
    percent. The existing rule establishes a performance standard that 
    allows for several methods of compliance. One acceptable method of 
    compliance is to limit the rate of production of coal to permit the 
    existing ventilation system to maintain the level of methane below 1.0 
    percent. In all cases, however, increasing the quantity or distribution 
    of air continues to be an accepted means of reducing methane levels. No 
    safety benefit would be derived from disallowing reduced coal 
    extraction rates as a means of maintaining methane levels under 1.0 
    percent.
        The final rule retains the language of proposed 
    Secs. 75.323(b)(1)(i), 75.323(b)(1)(iii), and 75.323 (b)(2)(i) and 
    (b)(2)(ii) which is identical to the wording of the existing standards. 
    An in-depth discussion of the reproposal of provisions concerning the 
    installation and removal of mechanized mining equipment is presented in 
    the General Discussion section of this preamble.
    
    Section 75.324  Intentional Changes in the Ventilation System
    
        This section addresses the precautions that must be taken when a 
    significant change is made to the ventilation system. MSHA did not 
    propose any change to existing Sec. 75.324 and is not making any 
    revisions in the final rule.
        Questions had been raised concerning the language, ``materially 
    affect the safety or health of persons in the mine'' that appears in 
    the existing standard. The phrase is important in that it identifies 
    those ventilation changes that require approval of the MSHA district 
    manager under Sec. 75.370(c). MSHA regards it as impractical to follow 
    a ``cookbook'' approach to identifying what will or will not require 
    approval. Each particular circumstance is to be reviewed by the 
    operator on its own merits. To illustrate the Agency's expectations, 
    the following is a list of some examples of what MSHA considers 
    intentional changes that would materially affect the safety or health 
    of miners. These examples are not meant to include all possibilities, 
    but are meant to provide some general guidance: adding a new shaft; 
    bringing a new fan on line; changing the direction of air in an air 
    course; changing the direction of air in a bleeder system; shutting 
    down one fan in a multiple fan system; starting a new operating section 
    with ventilating quantities redistributed from other sections of the 
    mine; changing entries from intakes to returns and vice versa; and any 
    change that affects the information required by Sec. 75.371, Mine 
    ventilation plan; contents.
        Comments were specifically solicited on issues raised in the 
    preamble discussion to the proposal. In response, written comments were 
    received from one commenter. These comments were reinforced by several 
    speakers at the public hearings. Other commenters indirectly referred 
    to Sec. 75.324 and stated that the phrase, ``materially affect the 
    safety or health of persons in the mine'' is accepted and understood by 
    the mining community.
        One commenter suggested that the person designated by the operator 
    to supervise ventilation changes should be a certified person that is 
    knowledgeable of the mine's ventilation system. The results of changes 
    to a complex ventilation system are not always easy to predict, and for 
    that reason caution must be used when making significant changes to one 
    air split or several air splits. The balance of splits can be affected 
    and may result in air reversals, dead air spaces, or insufficient air 
    flow in critical areas. For this reason, such changes must be evaluated 
    by a certified person examining the affected areas to determine that 
    the areas are safe before production is resumed. Therefore, the Agency 
    believes that it is to be an unnecessary burden to also have 
    ventilation changes supervised by a certified person. Thus, the 
    suggestion of the commenter has not been adopted in the final rule.
        This commenter also suggested that the provisions of Sec. 75.324 
    should apply to all intentional changes which alter the air current in 
    any section or area of the mine by 10 percent or more, or by 9,000 cfm 
    or more, whichever is less and that such change be considered to affect 
    the entire mine. The commenter recommended the miners' representative 
    be afforded the right to accompany the certified person to evaluate the 
    effects of the ventilation change and that a preshift examination of 
    the mine be conducted to assure that the mine is safe before electric 
    power is restored.
        The commenter also suggested that a record be maintained of all 
    ventilation changes to include the names of all persons involved with 
    the change, the date and time of the change, and results and locations 
    of air quality and quantity measurements taken both before and after 
    the change. The commenter stated that the record should be made in an 
    approved book within 24 hours of the change and that the record should 
    be signed and countersigned. Finally, the commenter recommended that 
    the mine ventilation map should be updated immediately after the 
    ventilation change is made and that within 24 hours of the change, the 
    updated map should be made available to the miners' representative and 
    a copy sent to the district manager. Section 75.370(c) requires that 
    any change to the ventilation system that alters the main 
    
    [[Page 9780]]
    air current or any split of the main air current in a manner that could 
    materially affect the safety or health of the miners, or any change to 
    the information required in Sec. 75.371 shall be provided to and 
    approved by the district manager before implementation. The final rule 
    requires that this information be provided to the miners' 
    representative at least 5 days before submittal to the district manager 
    (See Sec. 75.370 for full discussion). MSHA believes that this 
    provision provides necessary protection for miners.
        One commenter stated that the standard is reactive and that MSHA 
    routinely cites mine operators after a methane explosion or ignition. 
    MSHA believes that the standard is designed to assure that operators 
    are proactive and develop plans that prevent hazardous conditions. The 
    Agency anticipates that with the clarification provided through this 
    rulemaking, operators will obtain MSHA approval prior to making 
    intentional ventilation changes that materially affect the safety and 
    health of miners, thereby preventing potentially hazardous conditions. 
    When questions arise as to whether an anticipated change requires prior 
    approval, MSHA is available to provide guidance as to whether approval 
    is necessary.
    
    Section 75.325  Air Quantity
    
        The quantity of air in cubic feet per minute (cfm) is an important 
    measure of underground coal mine ventilation. It is essential for 
    miners' health and safety that each working face be ventilated by a 
    sufficient quantity of air to dilute, render harmless, and carry away 
    flammable and harmful dusts and gases produced during mining. An 
    insufficient quantity of air at a working face could permit methane to 
    accumulate and lead to an explosion. Section 75.325 generally 
    establishes the quantities of air that must be provided and the 
    locations underground where these quantities must be provided.
        Section 75.325(d) requires that areas where mechanized mining 
    equipment is being installed or removed be ventilated and that the 
    minimum quantity of air and the ventilation controls necessary to 
    provide these quantities be specified in the approved mine ventilation 
    plan. The final rule adds the word ``minimum'' to the phrase, 
    ``quantity of air'' that appears in the existing standard and the 
    proposal. The existing standard was reproposed without change. An in-
    depth discussion of the reproposal of provisions concerning the 
    installation and removal of mechanized mining equipment is presented in 
    the General Discussion section of this preamble.
        Only a few comments were received that were specific to paragraph 
    (d). One commenter discussing Sec. 75.371(r) suggested that the 
    quantity of air required by Sec. 75.325(d) to be specified in the plan 
    should represent the ``minimum'' quantity to be provided and that the 
    location specified should be identified as typical so as to give the 
    mine the flexibility to adapt to conditions. This comment is consistent 
    with MSHA's intent for the proposal and helps to clarify it. Therefore, 
    the word ``minimum'' has been inserted into the final rule in both 
    Sec. 75.371(r) and paragraph (d) of Sec. 75.325. Obviously, mine 
    operators can have air quantities which exceed the minimum specified in 
    the mine ventilation plan. MSHA agrees conceptually with a comment that 
    the ventilation scheme shown in the plan should be representative of 
    the method of ventilation to be used. However, MSHA does not adopt this 
    comment because the plan must also be specific enough so that the 
    operator, the miners, the representative of miners, and MSHA are 
    assured that the areas are being adequately ventilated.
        Other commenters suggested that the total quantity of air to be 
    delivered to a longwall needs to be specified in the mine ventilation 
    plan. In support of the suggestion the commenter stated that the 
    inclusion of the word ``total'' recognizes that some mines may use belt 
    air at the set up or tear down phase while some intake air may be 
    diverted to ventilate bleeders, battery chargers or compressors and, 
    therefore, the total quantity of air being delivered to the longwall 
    face should be the figure with which MSHA is concerned. The commenter 
    stated further that the recommendation recognizes that conditions vary 
    greatly from mine to mine, coal seam to coal seam, even from one 
    longwall panel to the next panel of the same mine. The commenter added 
    that while a specified amount of air can be delivered to a recovery 
    face, and pressure can be placed on the gob, it is impossible to 
    guarantee a specified volume or velocity of air at the recovery point.
        MSHA agrees that the total air quantity provided to a recovery face 
    is of importance; however, the distribution of this air is also 
    important. The volume of air being delivered to the longwall face 
    during equipment removal is important because of the types of 
    activities that occur (e.g. cutting and welding and the operation in 
    some cases of considerable numbers of diesel powered vehicles) and the 
    fact that it is along the face that the majority of miners work and 
    where an ignition hazard exists. It is important to know exactly how 
    areas where mechanized equipment is being installed or removed will be 
    ventilated. Therefore, this suggestion has not been included and the 
    rule.
        Commenters were concerned about the ventilation of a longwall face 
    prior to the first gob fall. This type of concern should be handled 
    through the mine ventilation plan. Paragraph (d) only deals with areas 
    were mechanized mining equipment is being installed or removed and not 
    where mining is in progress.
    
    Section 75.330  Face Ventilation Control Devices
    
        The final rule adds a new paragraph (c) adopting the proposal 
    language. The new paragraph (c) requires that when line brattice or any 
    other face ventilation control device is damaged to an extent that 
    ventilation of the working face is inadequate, production activities in 
    the working place are required to cease until necessary repairs are 
    made and adequate ventilation is restored. MSHA notes that before 
    issuing a citation for a violation of this provision, an inspector 
    would normally be expected to measure the air quantity to determine 
    whether adequate ventilation is being maintained.
        Some commenters considered the proposed regulation redundant since 
    operators must already maintain minimum air quantities at the face, 
    thereby making repairs necessary to maintain the required quantity. 
    Face ventilation controls are a critical feature of reliable 
    ventilation. As such, maintaining these controls in good condition and 
    making repairs necessary to restore ventilation is sound safety 
    practice. To do less invites increased risk of a methane ignition and 
    elevated respirable dust. Also on a practical level most miners on a 
    working section do not have a means of measuring air quantities. 
    However, miners can determine when ventilation controls are damaged 
    appreciably and are likely to adversely affect the air quantity.
        One commenter indicated that entire working sections might be shut 
    down to repair a ventilation control at any one face with no 
    corresponding safety benefit. The final rule provides that ``production 
    activities in the working place shall cease'' until adequate 
    ventilation is restored. Unless elevated methane levels or some other 
    problem existed, the entire section would not be shut down for repair 
    of a ventilation control.
        Some commenters asserted that controls may be slightly damaged 
    while still maintaining quantities in excess of 
    
    [[Page 9781]]
    the requirements at the face. Similarly, commenters worried that 
    numerous citations would be issued based solely on the appearance of 
    the controls, even though the minimum required face air quantities are 
    exceeded. These commenters stated that the only reliable indicator is 
    an air measurement.
        MSHA agrees that the only precise indicator of air quantity is a 
    measurement. Accordingly, MSHA anticipates that noncompliance decisions 
    will be based on air measurements which show ``ventilation of the 
    working place is inadequate.'' However, ventilation controls which are 
    in poor condition are likely to cue an inspector to conduct an air 
    measurement.
        Other commenters generally expressed the view that the requirements 
    of Sec. 75.330, even considering the proposed revision, are inadequate 
    to fully address the issue of face ventilation. According to these 
    commenters, additional requirements are needed, including: proper 
    installation and maintenance criteria for face ventilation control 
    devices, requirements for providing devices continuously from the last 
    open crosscut to the working face, immediate repair of these devices if 
    damaged by a fall or otherwise, providing sufficient space between the 
    line curtain and the rib and maintaining the area free of obstructions, 
    and minimizing leakage while providing installations which permit 
    traffic to pass without adversely affecting ventilation. Further, the 
    commenters asserted that only cumulatively can the desired result be 
    obtained through these requirements and that additional requirements 
    would empower individual miners to take corrective actions when needed.
        Each of these suggestions is a desirable ventilation practice which 
    MSHA supports. However, the final rule is not intended to set detailed 
    standards for the installation of ventilation control devices. Instead, 
    the rule addresses minimum requirements for face air quantities and 
    requires the face ventilation system used to deliver these quantities 
    to be maintained.
        Some commenters indicated a concern about so-called ``deep-cut'' 
    mining wherein continuous miners, by remote control, develop cuts from 
    25 to 60 feet inby permanent roof support. Commenters questioned the 
    adequacy of face ventilation where ventilation controls may be 30 to 50 
    feet from the face. Specifically, questions were raised about: whether 
    adequate ventilation actually reaches the face in ``deep cuts'' to 
    dilute methane; whether more frequent air measurements are needed; 
    whether methane checks are representative of face concentrations; 
    maximum feasible cut depth and ventilation device distance; respirable 
    dust in ``deep cuts;'' proper maintenance of ventilation control 
    devices; how ventilation is maintained after the continuous miner is 
    withdrawn from the cut; roof bolter ventilation; and differences 
    between scrubber systems and sprayfan systems. Another commenter noted 
    that historically most roof fall fatalities have occurred within 25 
    feet of the face. This commenter asserted that the deep-cut mining 
    system helps to resolve this problem and reduce exposure. The commenter 
    continues that to prohibit any variation from the 10 foot line curtain 
    distance requirement would adversely affect safety of the miners 
    working in the area.
        MSHA agrees that each of these issues is important. The appropriate 
    vehicle to address these specific concerns is the mine ventilation plan 
    required by existing Sec. 75.370. The mine ventilation plan provides 
    the necessary latitude to address the diversity of mining conditions 
    found throughout the country. Details of each system must be shown in 
    the plan and must be specific to the conditions at each mine where such 
    a system is employed. Also, MSHA's review and approval of mine plans 
    includes an onsite investigation to evaluate the system and to assess 
    the adequacy of the specified plan parameters. In addition, inspectors 
    routinely evaluate the suitability of the mine ventilation plan during 
    regular mine inspections.
        The commenter's concerns about methane checks in ``deep cuts'' is 
    addressed by the final rule Sec. 75.362(d)(2) which requires that 
    methane tests be made ``at the face.'' This new requirement will assure 
    that measurements are taken at the location where the hazard is most 
    likely to occur. Testimony received at the public rulemaking hearings 
    indicated that technology exists in the form of extendable probes that 
    can be used to take these measurements, without putting miners at 
    additional risk from fall of ground.
    
    Section 75.332  Working Sections and Working Places
    
        Working sections and working places are the areas of a coal mine 
    with the greatest amount of activity and the largest concentration of 
    workers. They are the location of the greatest number of potential 
    ignition sources. They therefore harbor the greatest risk of accidents 
    such as methane ignitions and explosions and equipment fires. Section 
    75.332 addresses the ways these areas are ventilated to reduce the 
    likelihood of an accident on one section impacting another section, 
    with deadly consequences. Generally, Sec. 75.332 provides that each of 
    these areas must be ventilated with a separate split of fresh air that 
    has not been used to ventilate another working area or an area where 
    mining has ceased if this area cannot be examined. When ventilated in 
    this manner, the products from a fire on one section will not 
    contaminate another section and methane in worked-out areas will not be 
    carried to working sections by the ventilating air stream.
        The final rule provides that each working section and each area 
    where mechanized mining equipment is being installed or removed, shall 
    be ventilated by a separate split of intake air directed by overcasts, 
    undercasts or other permanent ventilation controls. The final rule 
    adopts the language of proposed Sec. 75.332(a)(1), which is identical 
    to existing Sec. 75.332(a)(1). An in-depth discussion of the reproposal 
    of provisions concerning the installation and removal of mechanized 
    mining equipment is presented in the General Discussion section of this 
    preamble.
        Several commenters responded to Sec. 75.332(a)(1). Some commenters 
    suggested that the standard be revised to permit the installation of 
    mechanized mining equipment in either the return or intake air courses 
    of working sections provided the air had not been used to ventilate any 
    worked-out areas, areas where pillars have been recovered, or bleeder 
    systems. The commenters maintained that prohibiting the installation of 
    longwall equipment on the same split of air as a developing unit delays 
    the installation of a mining system. The commenters further observed 
    that this mining equipment consists mainly of steel conveyor sections 
    and roof supports that contain a 95 percent water-based hydraulic fluid 
    which does not burn. Therefore, according to these commenters, longwall 
    mining equipment can safely be installed on the intake side of an 
    active mining unit and, with monitoring, in the return air course of an 
    active mining unit.
        The safety benefits of using separate splits of air to provide 
    ventilation are well established. A primary benefit of such a provision 
    is to protect workers down-wind from being put at risk by events up-
    wind from their location. Among the most serious of these risks is 
    miners being overcome by the products of combustion or an explosion.
        In Miner's Circular 50, ``Explosions and Fires in Bituminous-Coal 
    Mines'' published by the Bureau of Mines in 
    
    [[Page 9782]]
    1954, the authors state that when air travels a long path through a 
    mine, it gradually becomes depleted of oxygen and may become so 
    contaminated with other gases that it no longer is healthful, or it may 
    accumulate enough explosive gas to present an explosion hazard. The 
    authors go on to state that when the air is divided into several 
    splits, each traveling a short path, better air can be furnished to 
    each group of persons in the mine. Further, if a local explosion or 
    fire should occur, the poisonous gases evolved may be confined to one 
    section and the force of the explosion and the gases may kill all the 
    persons in that particular section but may not affect other sections of 
    the mine. According to the authors, when a mine is ventilated by a 
    continuous current of air, the miners on the return side of an 
    explosion or fire probably will be killed or overcome by the poisonous 
    gases and that judicious splitting of the air is a safeguard against 
    this eventuality.
        Similarly, Stefanko states in the 1973 edition of the Society of 
    Mining Engineers (SME) Engineering Handbook that splitting the air is 
    recognized as being necessary for safety and presents only minimal 
    power cost.
        The commenters implied that because longwall mining equipment is 
    largely noncombustible, this danger is minimized for workers down-wind 
    on an active mining section. This reasoning overlooks the fact, 
    however, that the installation of a longwall is labor-intensive, 
    involving cutting and welding in the presence of methane and coal, as 
    well as machinery operating under load. These conditions add 
    contaminants to the ventilating current, and increase the possibility 
    of a fire or explosion. Likewise, a longwall being installed on the 
    return side of an active mining section would expose the miners doing 
    the installation to the dust and gases, and the results of a fire or 
    explosion, from the section. Even with monitoring, miners would be put 
    at risk as their opportunities for escape would be limited. For these 
    reasons, the final rule does not adopt the commenters'' suggestion.
        One commenter also suggested that ``approved ventilation controls'' 
    be required instead of specifying that overcasts, undercasts or other 
    permanent ventilation controls be used to direct intake air. The 
    commenter explained that this would allow operators the flexibility of 
    submitting plans that allow the use of temporary controls in some 
    instances.
        Temporary controls to split air are not as reliable as permanent 
    controls. The first explosion at the Scotia Mine in 1976 which killed 
    15 miners, was due in part to the improper use of a temporary 
    ventilation control where a permanent control (i.e., an overcast) 
    should have been used. More recently, the explosion that occurred 
    during the set up of a longwall at the Golden Eagle Mine in 1991 which 
    injured 11 miners involved the removal of two permanent ventilation 
    controls and the replacement of these controls with temporary controls. 
    As these and other accidents illustrate, the ventilation controls that 
    deliver air to working areas are vitally important to miners'' safety. 
    Therefore, the final rule requires that these controls be permanent in 
    nature and not temporary.
        Another commenter indicated that the use of temporary controls 
    would lower worker exposure to hazards by not requiring repeated 
    handling of permanent control materials which can be heavy. Proper 
    handling practices and modern materials can reduce the risk of injuries 
    associated with handling construction materials. MSHA considers these 
    risks lower than the dangers of using temporary controls in lieu of 
    permanent controls.
    
    Section 75.333  Ventilation Controls
    
        The primary means for directing air from the outside, through the 
    mine openings, to the working areas and back to the surface is through 
    the use of ventilation controls: either permanent controls, such as 
    stoppings (walls), overcasts or undercasts (air bridges), and doors, or 
    temporary controls, such as line brattice (curtains). Permanent 
    ventilation controls are designed for long term use while temporary 
    controls are intended for use on a short term basis. In general, 
    Sec. 75.333 specifies where each type of control can be used and how 
    each permanent control is to be constructed. It is essential that 
    ventilation controls be correctly constructed, maintained, and properly 
    located to provide ventilation to working sections and other areas 
    where it is needed to dilute methane, respirable coal mine dust and 
    other contaminants, and provide miners with a safe and healthful work 
    environment.
        The final rule revises paragraphs (a), (b)(1), (b)(3), (b)(4) and 
    (e)(1) of existing Sec. 75.333, and adds a new paragraph (h). Revisions 
    to paragraphs (a) and (e)(1) address the durability of stoppings, while 
    the revisions to (b)(1), (b)(3) and (b)(4) address ventilation controls 
    required when continuous haulage systems are used. New paragraph (h) 
    requires all permanent ventilation controls, including seals, to be 
    maintained to serve the purpose for which they were built.
        The use of continuous haulage systems, particularly in low seam 
    coal mines, is becoming more common. The final rule specifically 
    addresses continuous haulage systems in paragraphs (b)(1), (b)(3) and 
    (b)(4) of the rule and clarifies where temporary controls are an 
    acceptable means of ventilation control when these systems are used. 
    Continuous haulage systems utilize mobile bridge conveyors or similar 
    mechanisms to transport coal directly from a continuous mining machine 
    to a low profile belt. As the continuous mining machine moves from 
    place to place, the continuous haulage system slides back and forth 
    along a low profile conveyor belt using a ``dolly'' or other travel 
    mechanism. The low profile conveyor belt then transports the coal to 
    the section conveyor belt.
        The existing rule permits the use of temporary ventilation controls 
    in lieu of permanent ventilation controls to separate continuous face 
    haulage systems from return, intake, and primary escapeway entries in 
    rooms developed 600 feet or less from the centerline of the entry from 
    which the rooms were developed. This practice is consistent with 
    longstanding MSHA policy, which recognizes that these rooms are used 
    for a short duration and the minimum air quantity must be maintained 
    regardless of the controls used.
        Existing paragraph (b)(1) allows temporary controls to separate 
    intake and return air courses in rooms driven 600 feet or less from the 
    centerline of the entry from which the room was developed. The final 
    rule adds to existing paragraph (b)(1) the proposed language clarifying 
    that the use of temporary controls in these rooms is also acceptable 
    when continuous haulage systems are used. This change responds to 
    commenters who point out that the rooms in which the continuous haulage 
    systems are installed are continuously attended by the operators of the 
    system and an immediate response to any safety related problem with the 
    system or the ventilation controls would be expected. Commenters also 
    noted that two or three rooms are often concurrently developed using a 
    continuous haulage system and the life of the actively developing rooms 
    is often less than three days. As a result of this short life, mining 
    in these rooms is often completed before construction of permanent 
    controls is finished. Also, access to the continuous haulage system is 
    required through crosscuts for maintenance and operation of the system.
        Under paragraphs (b)(3) and (b)(4) the proposal would have required 
    belt and 
    
    [[Page 9783]]
    intake separation to the outby travel point of the dolly and belt and 
    primary escapeway separation to the inby most travel point. Commenters 
    indicated confusion because of the distinction between intake and 
    primary escapeway separation and believed that conflicts would exist. 
    Commenters also suggested that the language proposed to address the use 
    of temporary ventilation controls for continuous haulage systems was 
    confusing and contradictory. The final rule revises the requirements of 
    proposed paragraphs (b)(3) and (b)(4) to respond to these comments.
        Paragraph (b)(3) of the final rule retains the requirement that 
    permanent controls be provided to separate belt conveyor haulageways 
    from intake air courses when the air in the intake air course is used 
    to provide air to active working places. The final rule also retains 
    the proposed provision that when continuous haulage systems are used in 
    rooms less than 600 feet from the centerline of the entry from which 
    the rooms were developed, temporary stoppings or other temporary 
    ventilation controls may be built and maintained to provide the 
    required separation.
        Commenters stated that new technology may result in continuous 
    haulage systems with the outby point of travel of the dolly extending 
    considerably beyond the 600 feet distance. The commenters noted that 
    such an extended length of temporary controls could result in 
    unanticipated adverse consequences for the ventilation system, and 
    suggested that a maximum distance of 300 feet outby the inby point of 
    travel of the dolly be established for the use of temporary ventilation 
    controls. MSHA agrees that extensive use of temporary ventilation 
    controls can create problems, including excessive leakage and the 
    possible short circuiting of air. The final rule, therefore, limits the 
    distance that temporary controls may be used to separate continuous 
    haulage systems from intake air courses, including the primary 
    escapeway. The final rule permits temporary controls to be used from 
    the point of deepest penetration of the conveyor belt entry to the most 
    outby point of travel of the dolly or 600 feet, whichever distance is 
    the less. As a result, 600 feet is the maximum linear distance of entry 
    in which temporary controls may be used for separation of air courses. 
    The 600 feet would be measured as a straight-line distance from the 
    point of deepest penetration in the conveyor belt haulage entry. This 
    approach comports with the 600 foot limit for the use of temporary 
    stoppings in rooms and allows a reasonable use of temporary ventilation 
    controls with continuous haulage systems, while preserving the 
    integrity of the ventilation system. At present, MSHA would expect that 
    the most outby point of travel of the dolly would govern since MSHA is 
    not aware of any continuous haulage systems which travel more than 600 
    feet outby the point of deepest penetration.
        Paragraph (b)(4) of the final rule continues to require permanent 
    stoppings or other permanent ventilation control devices to separate 
    the primary escapeway from the belt and trolley haulage entries, as 
    required by Sec. 75.380(g). Commenters suggested that for the purposes 
    of Sec. 75.380(g), the definition of loading point in proposed 
    paragraph (b)(4) be revised to be the outby point of travel of the 
    dolly as opposed to the inby point of travel. The final rule adopts 
    this suggestion and requires separation by permanent stoppings to be 
    maintained to the outby point of travel of the dolly or 600 feet from 
    the point of deepest penetration, whichever distance is less, to 
    separate the haulage entry from the primary escapeway. The provisions 
    of Sec. 75.380(g) continue to allow the district manager to require a 
    greater or lesser distance for this separation.
        In response to questions about acceptable construction methods and 
    materials for permanent ventilation controls (excluding seals) MSHA 
    proposed eliminating the definition of ``durable'' in paragraph (a) and 
    to modify paragraph (e)(1). The proposal would have required these 
    controls to be constructed in a manner and of materials that result in 
    a construction that has been tested and shown to have a minimum 
    strength of 39 pounds per square foot as tested under ASTM E72-80 
    Section 12--Transverse Load-Specimen Vertical, load only (ASTM E72-80). 
    The 8-inch hollow-core concrete block stopping with mortared joints, to 
    which all other constructions were tied under the definition of durable 
    in the existing standard, has been tested and shown to have a minimum 
    strength of 39 pounds per square foot.
        MSHA received numerous comments questioning the validity of the 
    ASTM E72-80 test for determining acceptability of underground 
    ventilation controls. Commenters questioned the appropriateness of a 
    strength requirement of 39 pounds per square foot and the relevance of 
    this value to the in-mine conditions. After review, MSHA continues to 
    believe that use of the ASTM E72-80 test to determine that the relative 
    strength of a ventilation control construction is appropriate and the 
    final rule retains this standard. However, MSHA sees merit in some of 
    the suggestions made by commenters. Commenters suggested that some 
    constructions can not be tested according to the ASTM test, some 
    constructions that are widely used in coal mines do not meet the 39 
    pound per square foot threshold, and the ASTM test can only be run at a 
    limited number of locations nationwide.
        After reviewing all of the comments received and based on 
    experience with various construction methods and materials used for 
    permanent ventilation controls since the inception of the Mine Act, the 
    final rule recognizes traditionally accepted construction methods for 
    permanent ventilation controls, and retains the ASTM test for new 
    materials and methods. Controls made with new materials or methods must 
    be comparable in strength to controls made with traditionally accepted 
    materials or methods.
        Since the inception of the Mine Act, a number of traditionally 
    accepted construction methods have performed adequately and have served 
    their intended function of separating air courses. These traditionally 
    accepted construction methods are: 8-inch and 6-inch concrete blocks 
    (both hollow-core and solid) with mortared joints; 8-inch and 6-inch 
    concrete blocks dry-stacked and coated on both sides with a strength 
    enhancing sealant suitable for dry-stacked stoppings; 8-inch and 6-inch 
    concrete blocks dry-stacked and coated on the high pressure side with a 
    strength enhancing sealant suitable for dry-stacked stoppings; steel 
    stoppings (minimum 20-gauge) with seams sealed using manufacturer's 
    recommended tape and with the tape and perimeter of the metal stopping 
    coated with a suitable mine sealant; and lightweight incombustible 
    cementatious masonry blocks coated on the joints and perimeter with a 
    strength enhancing sealant suitable for dry-stacked stoppings. In 
    addition, 4-inch concrete blocks may be used in the above applications 
    in seam heights less than 48 inches. Tongue and groove 4-inch concrete 
    blocks coated on both sides with a strength enhancing sealant suitable 
    for dry-stacked stoppings may be used in coal seams of any height. The 
    sealants referred to in this paragraph would be applied in the 
    thickness recommended by the manufacturer. MSHA maintains a list of 
    sealants which may be used for the above applications. This list is 
    available at each MSHA District Office. The final rule would continue 
    to permit these traditionally accepted construction 
    
    [[Page 9784]]
    methods to be acceptable for the construction of ventilation controls.
        For new construction methods or materials other than those used for 
    the traditionally accepted constructions identified above, the final 
    rule requires that the strength be equal to or greater than the 
    traditionally accepted in-mine controls. Tests may be performed under 
    ASTM E72-80 Section 12--Transverse Load-Specimen Vertical, load only, 
    or the operator may conduct comparative in-mine tests. In-mine tests 
    must be designed to demonstrate the comparative strength of the 
    proposed construction and a traditionally accepted in-mine control.
        As with the existing rule, the final rule would require, in 
    paragraph (e)(1)(ii), that all overcasts, undercasts, shaft partitions, 
    permanent stoppings, and regulators, installed after November 15, 1992, 
    be constructed of noncombustible material. Also, like the existing 
    standard, the final rule lists materials that would be suitable for 
    these controls. The final rule would also continue to prohibit 
    ventilation controls installed after November 15, 1992, from being 
    constructed of aluminum.
        Paragraph (h) of the proposal would have required that all 
    permanent ventilation controls, including seals, be maintained to serve 
    the purpose for which they were built. The final rule retains proposed 
    paragraph (h) with one revision. One commenter stated that the 
    paragraph should require all ventilation controls, including temporary 
    controls, to be maintained to serve the purpose for which they were 
    built. Given the importance of temporary controls devices in providing 
    for adequate ventilation, the final rule requires all ventilation 
    controls, both permanent and temporary, including all doors and seals, 
    to be maintained to serve the purpose for which they were built. This 
    standard applies to all ventilation controls, regardless of the 
    construction date.
        Relative to seal maintenance, MSHA does not intend that the 
    maintenance requirement be applied to seals located within another 
    sealed area. Additionally, the rule does not apply to seals which have 
    become consumed within a gob area which is ventilated and evaluated in 
    a manner approved in the mine ventilation plan.
        One commenter raised several questions concerning what MSHA would 
    consider to be an acceptable temporary stopping. MSHA has not defined 
    the term ``temporary ventilation control'' in the rule. The commenter 
    stated that, in the preamble to the proposal, MSHA refers to ``properly 
    constructed'' temporary stoppings but does not include a standard for 
    construction or installation and maintenance of temporary stoppings. 
    The commenter adds that temporary ventilation controls are a source of 
    potential leakage and are often susceptible to damage from roof and rib 
    falls and from mobile equipment. The commenter also refers to several 
    accidents where failure to maintain permanent or temporary ventilation 
    controls was a critical factor in the accident.
        MSHA agrees that to properly direct the flow of air and provide for 
    adequate face ventilation, temporary controls, as well as all permanent 
    ventilation controls, must be installed and maintained in an adequate 
    manner to control leakage. MSHA has accepted as temporary controls, 
    check curtains or other flame- resistant material approved by MSHA that 
    are constructed and installed in such a manner to minimize leakage. As 
    required by paragraph (h) of this section of the final rule, these 
    controls must be maintained to serve the purpose for which they were 
    built.
    
    Section 75.334  Worked-Out Areas and Areas Where Pillars Are Being 
    Recovered
    
        Worked-out areas, areas where coal extraction has been completed, 
    can pose deadly hazards to miners, including an explosive methane 
    accumulation, irrespirable atmosphere, and the possibility of fire from 
    spontaneous combustion. Section 75.334 establishes the requirements for 
    ventilation of these areas to mitigate these hazards. In general, 
    Sec. 75.334 requires that following mining, these areas are to be 
    sealed or ventilated. Section 75.334 also specifies the requirements 
    for evaluating the effectiveness of the ventilation of worked-out areas 
    so operators can determine that the ventilation system is functioning 
    as intended.
        The final rule revises paragraph (e) of the existing Sec. 75.334. 
    Existing paragraph (e) requires that each mining system be designed so 
    that worked-out areas can be sealed. The final rule adds to paragraph 
    (e) the proposed requirement that the location and sequence of 
    construction of proposed seals be specified in the approved mine 
    ventilation plan. Improper location and sequencing of seal construction 
    can have a dangerous effect on mine air quality and ventilation. As the 
    proper location and sequence of construction of seals is a mine-by-mine 
    determination, the mine ventilation plan provides the most workable 
    mechanism by which to assure proper air quality and ventilation of the 
    mine.
        Several commenters objected to including seal construction sequence 
    as part of the information to be submitted for approval in the mine 
    ventilation plan. Their rationale was that mining conditions change and 
    could result in a change in the sequence of seal construction. The 
    construction might then be delayed while approval for the change is 
    obtained. These commenters suggested that in some cases, delays in seal 
    construction could result in a hazard to miners. Other commenters 
    stated that the sequence of construction of seals is more appropriately 
    and more easily shown on the mine ventilation map required by 
    Sec. 75.372. Another commenter stated that the sequence of construction 
    should be subject to approval because the placement of seals if 
    improperly installed can cause adverse effects on the ventilation 
    system and gob gases. MSHA is sensitive to the concern that a delay in 
    approval could result in a hazard to miners and, as explained in the 
    preamble discussion of Sec. 75.370, if a delay in seal construction 
    would result in a hazard to miners the review and approval of the plan 
    can be expedited.
        MSHA agrees with the commenter that the location and sequence of 
    seal construction may be more easily, that is, more clearly shown on 
    the mine map required by Sec. 75.372 than in the written text of the 
    plan submitted under Sec. 75.371. The existing standard permits 
    appropriate information required under Sec. 75.371 to be shown on the 
    map required by Sec. 75.372. The effect is that the information both 
    appears on the ventilation map and in the ventilation plan and is 
    subject to approval. The discussion of Sec. 75.371(bb) further 
    addresses this point.
        Spontaneous combustion is the process through which coal or other 
    materials self heat by the absorption of oxygen. Paragraph (f) of 
    Sec. 75.334 addresses mines with a demonstrated history of spontaneous 
    combustion and those located in coal seams determined to be susceptible 
    to spontaneous combustion. Paragraph (f) requires that the approved 
    mine ventilation plan for these mines specify the measures that will be 
    used to detect methane, carbon monoxide, and oxygen concentrations 
    during and after pillar recovery, and in worked-out areas where no 
    pillars have been recovered; the actions that will be taken to protect 
    miners from the hazards of spontaneous combustion; and, if a bleeder 
    system will not be used, the methods that will be used to control 
    spontaneous combustion, accumulations of methane-air mixtures, and 
    other gases, dusts, and fumes in the worked-out area. 
    
    [[Page 9785]]
    
        Through meetings with various segments of the mining community, 
    MSHA became aware of a concern that paragraph (f) of existing 
    Sec. 75.334 may have been promulgated without the public being provided 
    the opportunity to adequately comment. Although MSHA believes that 
    existing paragraph (f) was promulgated properly, the Agency reproposed 
    paragraph (f) with wording identical to that used in existing 
    Sec. 75.334. The purpose of the reproposal was to assure MSHA received 
    and considered all pertinent comments.
        Several commenters to the existing rule suggested that bleeder 
    systems should not be required for all mines. These commenters stated 
    that in some mines the practice of ventilating worked-out areas 
    increases the risk of spontaneous combustion by supplying oxygen to 
    combustion-prone materials in these areas. They also requested that the 
    final rule promulgated in 1992 include provisions to address 
    spontaneous combustion. MSHA acknowledged the need to reduce the flow 
    of oxygen to areas where there is a likelihood of spontaneous 
    combustion, and included in the 1992 rule requirements for mine 
    ventilation plans to address spontaneous combustion in mines with a 
    demonstrated history of this hazard or mines that are located in coal 
    seams determined to be susceptible to spontaneous combustion.
        Experience gained through application of the existing standard has 
    demonstrated that a limited number of mines have experienced 
    spontaneous combustion problems. Studies by the Bureau of Mines have 
    identified the volatile properties of coal seams and have determined 
    that certain seams are susceptible to spontaneous combustion. The final 
    rule is directed to mines in these seams.
        MSHA is not suggesting that all coal mines will meet the test to 
    show susceptibility to spontaneous combustion. A demonstrated history 
    or the determination of susceptibility to spontaneous combustion is a 
    prerequisite to the applicability of paragraph (f). While it is true 
    that all coal oxidizes when exposed to air, this fact is not sufficient 
    to make the determination that a coal seam is susceptible to 
    spontaneous combustion. MSHA would expect that absent a demonstrated 
    history of spontaneous combustion in a mine, an operator would provide 
    the necessary data to demonstrate that the mine is susceptible to 
    spontaneous combustion so that the provisions of paragraph (f) should 
    apply. A number of methods are used to determine the self heating 
    tendency of a coal.
        However, MSHA is also mindful that some mines that have a 
    spontaneous combustion problem may be unable to reduce the oxygen 
    content to a sufficiently low level to mitigate spontaneous combustion. 
    For these mines, a bleederless system may not be appropriate. To 
    illustrate, it is well known that the oxygen level in a gob varies 
    depending on the location where the measurement is made. For example, 
    the periphery of a gob normally will have higher oxygen levels than the 
    interior of the gob. The oxygen level in the interior of the gob is 
    critical when dealing with spontaneous combustion. If conditions are 
    such that the oxygen content in critical areas within a gob cannot be 
    reduced below that necessary for a methane ignition to occur, a bleeder 
    system may provide the most safety. MSHA specifically solicited comment 
    on this subject; however, none was received.
        Under paragraph (f)(1), the approved ventilation plans for mines 
    that have or are susceptible to spontaneous combustion must specify 
    measures to detect methane, carbon monoxide, and oxygen concentrations 
    in worked-out areas. These measures must be taken during and after 
    pillar recovery and in worked-out areas where no pillars have been 
    recovered. The purpose of these measures is to determine if worked-out 
    areas will be ventilated or sealed. If the methane concentration or 
    other hazards in the worked-out area cannot be controlled while the 
    mine is limiting airflow to avoid spontaneous combustion, it may be 
    necessary to seal or to ventilate the worked-out area using a bleeder 
    system. These measures also help to determine the extent to which the 
    worked-out areas can be ventilated without increasing the spontaneous 
    combustion hazard.
        Under the provisions of paragraph (f)(2) the operator is required 
    to specify in the mine ventilation plan the actions that will be taken 
    to protect miners from the hazards of spontaneous combustion. 
    Protections from the hazards of spontaneous combustion might include: 
    Additional continuous monitoring of fire gases at strategic locations 
    underground, increased air sample collection and analysis, trending of 
    air contaminant data, increased examinations, and changes to the mine 
    ventilation system such as redistribution of air or pressure balancing. 
    This requirement would be triggered if the mine has a demonstrated 
    history of spontaneous combustion, or, if an evaluation of the 
    susceptibility of the coal seam to spontaneous combustion leads to a 
    mine operator determination that a bleeder system should not be used.
        One commenter stated that this rule is unnecessary because only a 
    limited number of mines actually have a demonstrated spontaneous 
    combustion problem. The commenter suggested that the petition for 
    modification (variance) process should be used to address this issue, 
    which would allow miners representatives to participate. The final rule 
    does not adopt this approach. To the extent practicable, an objective 
    of this rulemaking is to reduce the need for exceptions and paperwork. 
    In this case, the existing mine ventilation plan process provides a 
    ready-made mechanism for establishing the precautions necessary, on a 
    mine-by-mine basis, to protect miners from the hazards of spontaneous 
    combustion in a timely manner. In addition, under the final rule, 
    miners representatives are afforded input into the mine ventilation 
    plan.
        Another commenter stated that paragraph (f) should be directed more 
    to the detection and control of spontaneous combustion and not solely 
    at its prevention. The commenter offered examples of detection and 
    control techniques that could be used.
        MSHA agrees that spontaneous combustion prevention, detection and 
    control are all important when dealing with spontaneous combustion. The 
    final rule recognizes, however, that while prevention is the goal, 
    instances of spontaneous combustion will occur.
        Another commenter stated that the preamble to the proposal was not 
    correct in that it implied a need to limit airflow to avoid spontaneous 
    combustion. The commenter states that, to avoid spontaneous combustion, 
    miners must create a near-zero pressure differential across most areas 
    of concern. MSHA agrees that creating a ``near-zero pressure 
    differential'' will have the desired effect of limiting the airflow. In 
    a paper entitled ``Examination of Bleederless Ventilation Practices for 
    Spontaneous Combustion Control in U. S. Coal Mines'' presented at the 
    7th U.S. Mine Ventilation Symposium in June 1995, the authors report 
    that their study revealed that restricting airflow into mined-out areas 
    is recognized world-wide as a spontaneous combustion control measure 
    and that when designing a bleederless ventilation system critical 
    attention must be given to mine layout, seal construction, methane 
    drainage, regulations, monitoring, and emergency procedures. In 
    discussing the subject of air leakage, Koenning in a paper entitled 
    ``Spontaneous Combustion in Coal 
    
    [[Page 9786]]
    Mines'' presented at the 4th U.S. Mine Ventilation Symposium in June 
    1989, identified air leakage as the most often cited cause of 
    spontaneous combustion. In both of these papers, the authors emphasize 
    the need to properly design a bleederless ventilation system to reduce 
    the likelihood of spontaneous combustion and achieve the level of 
    worker safety desired. MSHA agrees with these authors that a 
    bleederless ventilation system must be designed to encompass all of the 
    factors identified. It was suggested by one commenter that measurement 
    of carbon dioxide should be included in the requirements of paragraph 
    (f). In discussing the gases required to be measured (methane, oxygen, 
    and carbon monoxide), the commenter stated that these gases alone will 
    not aid in the detection of spontaneous combustion in its incipient or 
    developed stage. The commenter suggested that miners be required to 
    monitor for carbon dioxide because, in the opinion of the commenter, 
    the trend in the ratio CO/CO2 is the only viable predictor.
        MSHA sees merit in the measurement of carbon dioxide as well as 
    other products of combustion to assist in the detection of spontaneous 
    combustion. However, the ratio CO/CO2 is not the only viable 
    predictor of spontaneous combustion. One researcher suggested that 
    carbon monoxide production is the earliest, detectable effect of 
    spontaneous heating. Others have suggested, following a series of 
    tests, that four gas ratios clearly indicated the development of 
    thermal runaway, but only the CO2- O2 ratio gave an 
    early warning of the heating in the coalbed.
        As can be seen, a number of methods of predicting the onset of 
    spontaneous combustion have been suggested. While paragraph (f)(1) 
    requires only the measurement of methane, oxygen, and carbon monoxide, 
    MSHA would not discourage operators from incorporating, as part of the 
    mine ventilation plan, any or all of these methods as well as other 
    appropriate methods to aid in the early detection of spontaneous 
    combustion.
    
    Section 75.340  Underground Electrical Installations
    
        Electrical installations can provide an ignition source for methane 
    and can represent a serious fire hazard underground. Typical electrical 
    installations are battery charging stations, substations, rectifiers 
    and certain water pumps. Section 75.340 requires that these 
    installations be ventilated and protected against fire. These 
    installations must also be housed in noncombustible structures or areas 
    or protected with fire suppressions systems, and be ventilated or 
    monitored to protect miners working down stream from the products of 
    combustion.
        MSHA proposed to revise paragraph (a) of existing Sec. 75.340 to 
    clarify the standard and to add requirements concerning alarms and 
    sensors. The final rule adopts the language in the proposal with one 
    modification. It replaces the word ``located'' with the word 
    ``housed.''
        Existing 75.340(a) requires that certain underground electrical 
    equipment be either located in a noncombustible structure or area or 
    equipped with a fire suppression system. Section 75.340 (a) also 
    requires that the equipment be ventilated by intake air, and lists 
    alternatives ways to do so in paragraphs (a)(1),(a)(2), and (a)(3). The 
    final rule adds language to paragraph (a)(3), the alternative which 
    establishes an acceptable means for monitoring the underground 
    electrical installations using sensors other than a Sec. 75.351 
    atmospheric monitoring system.
        MSHA sought in the proposal to clarify the application of existing 
    Sec. 75.340(a)(3). Paragraph (a)(3) of the existing rule provides for 
    the activation of doors upon the presence of certain indications of a 
    possible fire. The paragraph was appropriate for enclosed structures or 
    areas; but questions at informational meetings challenged its 
    applicability to the alternative where a fire suppression system was 
    used without an enclosure. To address the questions, the proposal 
    placed the requirements for noncombustible structures or areas and for 
    fire suppression systems into separate paragraphs. MSHA proposed that 
    one of the alternatives for ventilating with intake air (monitoring the 
    underground electrical installations using sensors other than a 
    Sec. 75.351 atmospheric monitoring system) was acceptable only if the 
    equipment was located in a noncombustible structure or area and not 
    acceptable if only a fire suppression system was used. This revision 
    eliminates the confusion that existed with the existing rule. It should 
    be noted that if an operator elects to locate this equipment in a 
    noncombustible structure or area, the operator would not be precluded 
    from also installing a fire suppression system.
        One commenter questioned the reason for separating fire suppression 
    and noncombustible structures, noting that there was no need for the 
    distinction in the rule. In objecting to the proposal, the commenter 
    stated that there should be several cumulative layers of protection, 
    including both fireproof enclosures and fire suppression systems. The 
    commenter includes several examples of fires involving compressors to 
    illustrate this point. MSHA has addressed concerns relative to 
    compressor fires in the final rule section dealing with compressors, 
    Sec. 75.344. Other examples cited by the commenter included explosions 
    caused by mobile equipment and a fire that occurred on a power center 
    located at the working section. The instances cited by the commenter 
    are not relevant to Sec. 75.340. The commenter argued that fire 
    suppression systems have not worked and uses the compressor fires 
    previously mentioned to illustrate the point. MSHA notes that there are 
    numerous instances where the systems have worked. However, in the vast 
    majority of these cases there is no documentation because there is no 
    requirement for reporting fires that are extinguished within 30 
    minutes.
        The final rule in paragraph (a)(1)(iii) revises existing paragraph 
    (a)(3) of Sec. 75.340 by adding 2 requirements. It adds a requirement 
    that a visual and audible alarm be provided on installations if the 
    (a)(1)(iii) alternative is selected. Also, when operating under this 
    alternative, monitoring of intake air that ventilates battery charging 
    stations must be done with sensors not affected by hydrogen.
        Some commenters noted their agreement with these proposed changes. 
    Noting that no single system is failsafe, one commenter suggested that 
    all the requirements of Sec. 75.340 be combined and made applicable in 
    all cases. The requirements would include; noncombustible structures, 
    fire suppression, ventilation directly to the return, additional 
    communications, continuous AMS monitoring for carbon monoxide, methane, 
    and hydrogen, along with automatic closing doors and temperature 
    protection. After consideration of the comments and the underlying 
    rationale, MSHA concludes that to require that the alternatives be 
    applied cumulatively in every case would be infeasible or impractical. 
    In addition, MSHA does not believe that these overly restrictive 
    requirements are necessary in all circumstances.
        Paragraph (a)(1)(iii) addresses electrical installations that are 
    equipped with doors that automatically close when sensor readings reach 
    certain levels. One of these action levels is a level for the optical 
    density of smoke. In Sec. 75.340 (a)(1)(iii)(B) of the proposal and the 
    preamble discussion on page 26371, MSHA refers to the optical density 
    of smoke of 0.05 per meter to characterize the sensitivity of smoke 
    detectors. As discussed in MSHA's opening statement to the ventilation 
    rulemaking hearings, 
    
    [[Page 9787]]
    the value used for the optical density of smoke is based on information 
    provided from the Bureau of Mines. MSHA pointed out that based on 
    comments received from the Bureau of Mines, this number is incorrect 
    and should be divided by 2.303 to conform to the internationally 
    accepted term of optical density. No commenter took issue with this 
    point. MSHA has made the correction in the final rule. One commenter 
    suggested that optical densities be increased and based on an ambient 
    to account for background dust. In contrast, another commenter 
    suggested that the specified optical density should be reduced by half. 
    MSHA has found insufficient justification to adopt either of these 
    suggestions and believes that the specified 0.05, corrected to 0.022 
    based on comments from the Bureau of Mines, is the appropriate level 
    for optical density used in Sec. 75.340. Existing Sec. 75.351 
    Atmospheric monitoring system (AMS), uses a level for optical density 
    of smoke of 0.05 per meter. MSHA recognizes that the level in 
    Sec. 75.351 should also be corrected. MSHA intends to correct the level 
    for optical density used in Sec. 75.351 in a future rulemaking. In the 
    meantime, MSHA will use an optical density of 0.022 per meter for 
    purposes of Sec. 75.340.
        The visual and audible alarm required in paragraph (a)(1)(iii) must 
    be situated so that it can be seen or heard by persons traveling in the 
    intake entry immediately adjacent to the installation. It was suggested 
    to MSHA that these electrical installations may be susceptible to fire 
    and the fire could go undetected. The visual and audible alarms would 
    provide additional safety at these installations by alerting miners in 
    the area.
        One commenter suggested that an alternative should be added to 
    carbon monoxide or smoke detection. The suggested alternative would be 
    to permit another means that would be approved by the district manager. 
    This suggestion has not been adopted since both carbon monoxide 
    monitoring and smoke detection have been shown to be effective and 
    reliable and can be used.
        One commenter stated that battery chargers located on working 
    sections do not present the same hazards as those located outby, along 
    the intake. The commenter suggested that chargers located on working 
    sections should be exempted from Sec. 75.340. MSHA disagrees. MSHA 
    believes that battery chargers present the same safety hazards 
    associated with other electrical equipment plus the charging of 
    batteries results in the liberation of hydrogen. There is a 
    demonstrated history of fires caused by battery chargers. The 
    requirements are necessary to safely operate chargers, regardless of 
    the location of the charger.
        One commenter suggested that all water pumps should be exempted 
    from Sec. 75.340 because fire history is limited. The standard already 
    exempts pumps that have limited fire hazard potential in paragraphs 
    (b)(2) through (b)(6). Pumps outside of the listed categories do 
    present hazards. As an example, a 200 horsepower pump exploded at a 
    mine in Virginia after an extended period of being overheated. An 
    example of a pump posing a limited hazard is an emulsion pump located 
    at or near the section that is moved as the section advances or 
    retreats. Emulsion pumps are considered for the purpose of Sec. 75.340 
    to be water pumps.
        Also, one commenter called attention to MSHA's omission of the word 
    ``or'' in two places in Sec. 75.340, Underground Electrical 
    Installations. MSHA agrees that the omission was inadvertent and so 
    stated in its opening statement at the ventilation hearings. In 
    Sec. 75.340, the word ``or'' has been inserted between paragraphs 
    (a)(1) (i) and (ii) dealing with alternative ventilation requirements 
    for noncombustible structures or areas and between paragraphs 
    (a)(1)(iii) (A) and (B) setting out criteria that would govern the 
    activation of automatic closing doors.
        Another commenter suggested that the signal from the visual and 
    audible alarms required by existing paragraph (a)(3) should be sent to 
    a surface location at the mine rather than being located outside the 
    installation. The commenter supported the suggestion by indicating that 
    a quicker response would thus be provided since the alarm would be 
    immediately noticed. In order to achieve an effective level of safety, 
    MSHA has provided in paragraph (a)(1)(iii) that the visual and audible 
    alarm be located outside of and on the intake side of the enclosure. 
    This location will permit persons traveling in the intake entry 
    immediately adjacent to the installation to see or hear the alarm. 
    Paragraph (a)(2) allows the use of an alternative system using an AMS 
    which would provide an alarm at the surface of the mine.
        Finally, one commenter objected to the use of the word ``located'' 
    in the phrase ``located in noncombustible structures or areas''. The 
    commenter argued that MSHA should use the word ``housed'' and that the 
    use of the word ``located'' actually reduces the protection intended by 
    Congress. MSHA does not agree with that interpretation and maintains 
    that in the context in which the word is used there is no meaningful 
    distinction between the two words. However, because the word suggested 
    by the commenter will not reduce safety and may add to the clarity of 
    the rule for some readers, it has been adopted in the final rule.
    
    Section 75.342  Methane Monitors
    
        Methane monitors are a critical link in the safety protections 
    designed to prevent mine explosions. Mounted on mining equipment which 
    works directly in the face, these instruments provide the first warning 
    that gas is being liberated in potentially dangerous quantities. 
    Methane monitors are relied upon to shut down mining equipment 
    automatically when gas concentrations reach 2 percent. The continued 
    operation of mining equipment under these conditions can lead to a 
    spark and catastrophic explosion.
        The final rule revises paragraph (a)(4) which addresses maintenance 
    and calibration of methane monitors that are required on underground 
    mining equipment to provide a warning to equipment operators when the 
    methane concentrations nears dangerous levels. Methane monitors also 
    automatically deenergize the equipment when methane approaches the 
    explosive range or if the monitor is not operating properly. The rule 
    requires that trained persons perform maintenance and calibration of 
    the methane monitors at least every 31 days and requires that 
    calibration records be maintained. The final rule does not adopt the 
    proposal which would have required that a written maintenance program 
    be available for inspection.
        Some commenters expressed the view that the proposed revisions were 
    unnecessary and recommended that they be deleted from the final rule. 
    Other commenters supported the proposed revisions and urged MSHA to 
    adopt additional requirements as well.
        Paragraph (a)(4) of the final rule requires that calibration and 
    maintenance of the monitors be performed by persons properly trained in 
    maintenance, calibration, and permissibility of the methane monitors. 
    One commenter expressed the view that no change was needed to the 
    existing rule. However, the rulemaking record also contains a number of 
    examples in which poorly maintained or improperly repaired methane 
    monitors have been found during the investigations of methane related 
    accidents.
        The final rule in paragraph (a)(4)(ii) requires that each operator 
    maintain a record of all calibration tests of methane monitors. As with 
    other recordkeeping requirements under the final rule, records must be 
    maintained in a secure 
    
    [[Page 9788]]
    book that is not susceptible to alteration, or may be kept 
    electronically in a computer system so as to be secure and not 
    susceptible to alteration. Some commenters recommended that a record be 
    kept of all maintenance performed on a methane monitor, urging that a 
    record is necessary to prove the maintenance is done. MSHA believes 
    that the revisions contained in the final rule, together with the 
    existing requirements, will assure an appropriate level of maintenance 
    without the need for additional records of maintenance.
        Some commenters expressed concern over the security of computer-
    based records, and offered examples of breaches of security in the 
    banking and national security fields. Others, however, advocated the 
    use of computers for the storage and retrieval of records as being 
    highly accurate, requiring less storage space and facilitating data 
    retrieval. MSHA agrees that security of required records is important. 
    It is also MSHA's objective to make the final rule requirements for 
    compilation and storage of records practical and in concert with modern 
    methods. To this end, the final rule requires that the record of 
    maintenance and calibration of methane monitors be maintained in secure 
    books that are not susceptible to alteration, and also permits these 
    records to be maintained electronically in a computer system so as to 
    be secure and not susceptible to alteration. The calibration record 
    will aid operators in tracking calibration activity and will serve as a 
    check to assure that calibrations are being conducted at least once 
    every 31 days. The record will also be reviewed by authorized 
    representatives of the Secretary and miners' representatives to 
    determine that calibrations are being conducted as required.
        Paragraph (a)(4)(iii) of the final rule requires that operators 
    retain the record of calibration tests for 1 year from the date of the 
    test. Records are to be maintained at a surface location at the mine 
    and made available for inspection by authorized representatives of the 
    Secretary and the representative of miners. A discussion of comments 
    concerning the use of computers to maintain records can be found in the 
    General Discussion of this preamble.
        Several commenters suggested that equipment not operated in the 
    face area also be equipped with methane monitors. Commenters noted 
    accidents which have occurred when this nonpermissible equipment has 
    ignited methane in outby areas. Commenters also asserted that equipment 
    used for the withdrawal of personnel during fan stoppages would be 
    safer if methane monitors were provided. An opposing comment indicated 
    that an expansion of the methane monitor coverage was not necessary 
    since methane is rarely associated with outby areas. Because of the 
    response time of methane monitors, and considering the speed at which 
    most outby equipment normally operates, it is unlikely that a monitor 
    would prevent a machine from entering a body of methane if such a 
    concentration were encountered. MSHA believes that methane monitors are 
    suitable and effective in face areas where coal is being cut, mined, or 
    loaded. However, MSHA does not believe that an expansion of coverage to 
    include all nonpermissible equipment is warranted.
        A number of commenters recommended that methane monitors should be 
    calibrated at least every 7 days rather than at least every 31 days as 
    provided by the existing standard. One commenter suggested daily 
    calibration. Commenters noted that methane monitors lose sensitivity 
    and that response time increases with monitor age and after exposures 
    to elevated methane concentrations. The existing requirement for 
    calibration of methane monitors at least every 31 days parallels the 
    recommendations of several manufacturers. The 31 day requirement 
    establishes a maximum time interval between calibrations. However, the 
    final rule also requires the operator to maintain methane monitors in 
    permissible and proper operating condition. Thus, under unusual 
    circumstances of use, it is possible that weekly or even more frequent 
    calibration may be necessary to comply with the standard.
        Comment was also received recommending an additional requirement 
    that calibration records be countersigned by the Maintenance Supervisor 
    or Chief Electrician at the mine. The final rule does not adopt this 
    recommendation. The purpose of the calibration record required under 
    the final rule is not the same as other records where countersigning is 
    required by the final rule. Countersigning requirements are directed at 
    informing upper mine management of hazardous conditions which require 
    their attention. While the calibration record has the potential to 
    assist mine management in identifying equipment problems, its main 
    function is to assist operators in assuring that timely calibration is 
    occurring.
        The proposal would have required that operators adopt a written 
    maintenance program for methane monitors. Commenters pointed out that 
    the existing standard already requires all permissible equipment, 
    including methane monitors, to be maintained in permissible condition. 
    MSHA agrees.
    
    Section 75.344  Compressors
    
        Section 75.344 deals with the use of air compressors underground. 
    As discussed in the introductory section of this preamble, MSHA stayed 
    Sec. 75.344(a) because of a concern over a possible overheating or fire 
    hazard. Improperly used or maintained air compressors can present a 
    significant risk of fire underground. MSHA determined that the cause of 
    the 1984 fire at the Wilberg Mine that claimed the lives of 27 miners 
    was an improperly maintained compressor. In general, Sec. 75.344 
    requires that most compressors be operated only while attended or 
    located in a noncombustible structure or area that is monitored for 
    temperature and carbon monoxide or smoke; have a fire suppression 
    system; and, automatically shut down in the event of a fire.
        The final rule revises the existing Sec. 75.344, including the 
    stayed paragraph (a), and supersedes interim Sec. 75.345. The final 
    rule recognizes that in some cases compliance with the existing rule 
    could result in heat buildup when a compressor is located in a 
    noncombustible structure or area. To address this possible hazard the 
    final rule provides an option. A compressor would be acceptable when 
    not located in a noncombustible structure or area provided it is 
    continuously attended by someone who can see the compressor at all 
    times, activate the fire suppression system and shut off the 
    compressor. Also, the existing rule is modified for compressors that 
    are located in a noncombustible structure or area. They must be 
    ventilated by intake air coursed directly into a return air course or 
    to the surface and equipped with sensors to monitor for heat and for 
    carbon monoxide or smoke. In addition, upon the activation of the fire 
    suppression system, the compressor must automatically deenergize or 
    shut off.
        The final rule does not include proposed paragraph (b)(2) which 
    provided an additional alternative means of ventilating compressor 
    installations located away from working sections and near a return air 
    course where a substantial pressure differential exists.
        Comments were solicited on the exemption for compressors having a 
    certain maximum horsepower. Comments were received both supporting and 
    opposing a possible revision to increase the limit from 5 to 30 
    horsepower. Because of the history of compressor fires, including the 
    1984 Wilberg mine disaster which resulted in 
    
    [[Page 9789]]
    27 fatalities, the existing limitation of 5 horsepower has not been 
    revised. One commenter questioned the proposal reference to 9 mine 
    fires which started in compressors between 1970 and 1992. The commenter 
    suggested that the nine fires was inaccurately low and referenced an 
    MSHA report which stated that 21 compressor fires occurred between 1977 
    and 1987. The preamble discussion addressing the number of fires was in 
    relation to underground coal mines. Other compressor fires have 
    occurred at surface coal mines and at noncoal mines. Regardless of the 
    number of compressors affected, however, the safety concerns remain the 
    same.
        Several commenters suggested that the cutoff for application of 
    Sec. 75.344 be changed from 5 horsepower for all compressors to 30 
    horsepower for reciprocating compressors and 5 horsepower for all other 
    types of compressors. The rationale for this recommendation was that 
    reciprocating compressors of up to 30 horsepower contain about the same 
    amount of lubricating oil as 5 horsepower compressors. This suggestion 
    was not included in the proposal, based on MSHA information (Report No. 
    06-292-87 of the Industrial Safety Division, Pittsburgh Safety and 
    Health Technology Center) that the predominant hazard for fire or 
    explosion in reciprocating compressors is not the lubricating oil, but 
    rather the formation of carbonaceous deposits in the discharge system. 
    MSHA received comments addressing the formation of carbonaceous 
    deposits in the discharge system indicating that the use of synthetic 
    oil prevents any carbonaceous accumulation. Commenters suggested that 
    all identified hazards would be eliminated through the use of synthetic 
    oils. However, commenters also noted that synthetic oils have a higher 
    flash point.
        MSHA has examined the subject of synthetic oils and found that 
    synthetic oils can be formulated with polyalphaolefins, polyglycols, 
    silicones, esters, phosphate-esters, and di-esters as the primary 
    ingredient. These compounds are also blended with mineral oils to form 
    synthetic lubricants. The rate of oxidation is varied among these 
    compounds. Of these types, only silicone based lubricants exhibit 
    virtually no oxidation and are used primarily where extremely high 
    temperatures are expected. Also, silicone based lubricants are 
    inherently fire resistant. Unfortunately, silicone based lubricants are 
    incompatible with reciprocating compressors and will rapidly lead to 
    failure of the compressor. Polyalphaolefins, polyglycols, and mineral 
    oil blends all contain hydrocarbons and have a tendency to varnish and 
    create deposits in air compressors. Accordingly, the final rule, like 
    the existing rule, exempts compressors of five horsepower or less and 
    the suggested revision to 30 horsepower has not been adopted.
        One commenter stated that modern compressor technologies allow for 
    much safer rotary screw compressor operation using non-defeatable 
    programmed safety controls, synthetic lubricants, automatic fire 
    suppression and shutdown, and other precautions. Although synthetic 
    lubricants offer some safety enhancement, they do not fully mitigate 
    the hazards. Also, considering the accident history including the 
    Wilberg disaster, MSHA has not provided an exemption for rotary screw 
    compressors.
        Existing Sec. 75.344 (a)(1) requires all compressors to be located 
    in noncombustible structures or areas and to be equipped with a heat-
    activated fire suppression system. During informational meetings it was 
    brought to MSHA's attention that in some instances requiring 
    compressors to be inside such a structure could present a hazard 
    through compressor overheating. Upon reviewing this potential effect of 
    the regulation, MSHA agreed. Therefore, before the existing standard 
    could become effective, MSHA stayed the application of paragraph (a)(1) 
    and included the standard in this rulemaking.
        The final rule addresses the potential of compressor overheating by 
    allowing a compliance alternative to enclosing the compressor. Heat is 
    generated at considerable rates by operating compressors. Improperly 
    used or maintained compressors can present a significant risk of fire. 
    To minimize this hazard, the rule specifies other installation and 
    operational requirements as well as providing for fire detection and 
    fire suppression. As recommended by commenters, the final rule also 
    provides for audible and visual alarms and automatic deenergization or 
    shut-off.
        Several commenters discussed the proposed revisions to paragraph 
    (a). One commenter urged that the term ``operation'' be clarified, 
    noting that compressors which are designed to automatically start when 
    necessary to rebuild air pressure should be protected. MSHA considers 
    compressors that are installed to automatically start when necessary to 
    rebuild air pressure to be in operation. MSHA agrees that these 
    compressors should be provided either a noncombustible structure (or 
    area) or an attendant. Accordingly, for the purpose of clarifying the 
    requirement, the final rule includes the commenter's recommendations. 
    Compressors which have been disconnected from the power or fuel source 
    would not be subject to the requirement under the final rule.
        Another commenter suggested that the person specified in paragraph 
    (a)(1) be trained. The commenter noted that the attendant would be of 
    little value if unaware of the appropriate response to a fire. The 
    commenter suggested that the person know how to deenergize the machine 
    and activate the fire suppression system manually. MSHA agrees and 
    notes that this knowledge is required under the proposal by requiring 
    that the attendant be capable of performing these tasks. MSHA believes 
    that any training necessary to meet this capability is implicit in the 
    standard and the proposal has been retained under the final rule.
        Another commenter suggested that an attendant be accepted as an 
    alternative to noncombustible structures or areas for a maximum of 8 
    hours. The commenter stated that 8 hours would provide sufficient time 
    for urgent roof bolting or construction work such as coating stoppings 
    or powering a jack hammer. After considering the comment, the suggested 
    time limit has not been adopted. MSHA believes that a continuous 
    attendant, always within sight of the compressor and capable of 
    responding as required, provides a level of protection equivalent to 
    the protection provided by an enclosure. Therefore, the final rule 
    allows either alternative to be selected. It should also be noted that 
    the final rule has been revised to require either a continuous 
    attendant or containment in a noncombustible enclosure or area.
        One commenter suggested that an alternative be provided in the rule 
    to allow for video monitoring of compressors as an alternative to 
    attendance or noncombustible enclosures. MSHA has not adopted the 
    suggestion since video monitoring would not provide an equivalent level 
    of safety compared to either an enclosure or attendance. There would be 
    a considerable time delay in responding to a video monitor as compared 
    to a nearby attendant who could immediately shut down the compressor, 
    activate fire suppression, discharge fire extinguishers, apply rock 
    dust, and take other necessary actions.
        Other commenters addressed an allowable distance within which the 
    compressor attendant must remain. In the preamble to the proposal, MSHA 
    solicited comments on the proposed language, ``can see the compressor 
    at all times'' versus having the attendant 
    
    [[Page 9790]]
    remain within some specified distance. Rationale was solicited for any 
    specific distances suggested. Several commenters supported the 
    proposal, noting that adjustment is inherently provided for high mining 
    heights and seam undulations since a low undulating seam would cause 
    the attendant to remain closer to the compressor. Another commenter 
    suggested that a maximum distance of 20 feet be specified. The 
    commenter reasoned that a maximum distance of 20 feet would assure that 
    the attendant could react to a fire quickly, noting that a compressor 
    fire would propagate rapidly. The commenter also voiced a concern over 
    travel time in low height mines and noted that distances over 20 feet 
    might allow a fire to get out of control before the attendant could 
    reach the machine.
        Another commenter was concerned with the proposed requirement in 
    (a)(1) that a person be able to see the compressor at all times. The 
    commenter suggested that the term ``close proximity'' be adopted noting 
    that a person could be in close proximity, e.g. in an adjacent 
    crosscut, but not within sight. The commenter suggested that this 
    should be acceptable since the person would still be able to activate 
    the fire suppression system. MSHA disagrees. The suggested situation is 
    not acceptable since a considerable delay could result before detection 
    of a problem if the person were not within sight of the compressor. In 
    such a case the person would be relying on the smell of smoke or some 
    indirect means of detecting a problem. Because of the potential fire 
    hazard associated with compressors, reaction time is critical. MSHA 
    continues to believe that reaction time is appropriately minimized if 
    the assigned person can see the compressor at all times, is capable of 
    deenergizing the unit, and is capable of activating the fire 
    suppression system. While agreeing that reaction time is critical and 
    after considering all of the comments, MSHA finds the arguments for not 
    specifying a set distance to be more persuasive. Therefore, the final 
    rule permits compressors to be continuously attended by a person 
    designated by the operator who can see the compressor at all times 
    during its operation. Any designated person attending the compressor 
    must be capable of activating the fire suppression system and 
    deenergizing or shutting-off the compressor in the event of a fire.
        If a compressor is not enclosed in accordance with (a)(2), the 
    compressor can be operated only while it can be seen by a person 
    designated by the operator according to (a)(1). In adopting this 
    approach, the proposed paragraph (a)(1) language was deleted. 
    Commenters indicated confusion over the similarity of proposed 
    paragraphs (a)(1) and (b)(1) of the existing rule. The final rule 
    combines these two requirements in (a)(1). The final rule requires both 
    that the person be able to see the compressor and be capable of 
    activating the fire suppression system.
        Paragraph (a)(2) of the final rule requires that compressors, if 
    installed in a noncombustible structure or area, be ventilated by 
    intake air coursed directly into a return air course or to the surface 
    and be equipped with sensors to monitor for heat and for carbon 
    monoxide or smoke. MSHA expects that an air quantity sufficient to cool 
    the compressor will be provided through the enclosure. The 
    manufacturer's operation manuals for compressors often specify an air 
    quantity or a maximum ambient temperature. The sensors required by 
    paragraph (a)(2) must deenergize power to the compressor, activate a 
    visual and audible alarm located outside of and on the intake side of 
    the enclosure, and activate doors to automatically enclose the 
    noncombustible structure or area when either of the conditions in 
    paragraph (a)(2)(i) or (ii) occurs. The visual alarm should be situated 
    so that it can be seen by persons traveling in the intake entry 
    immediately adjacent to the enclosure. The sensors must also deenergize 
    or shut-off the compressor in addition to closing the doors of the 
    enclosure.
        Paragraph (a)(1)(ii) specifies that the sensors shall deenergize 
    power to the compressor, activate a visual and audible alarm located 
    outside of and on the intake side of the enclosure, and activate doors 
    to automatically enclose the noncombustible structure or area when the 
    carbon monoxide concentration reaches 10 parts per million above the 
    ambient level for the area, or the optical density of smoke reaches 
    0.05 per meter. These levels are the same as required by the existing 
    rule. As discussed in MSHA's opening statement at the ventilation 
    rulemaking hearings, the value used for the optical density of smoke is 
    based on information provided from the Bureau of Mines. MSHA pointed 
    out that, based on comments received from the Bureau of Mines, this 
    number is incorrect and should be divided by 2.303 to conform to the 
    internationally accepted term of optical density. MSHA's remarks were 
    made in reference to the requirement in Sec. 75.340(a)(1)(iii)(B). The 
    final rule also makes a conforming technical revision to 
    Sec. 75.344(a)(2)(ii).
        Paragraph (e) of the final rule requires automatic deenergization 
    or automatic shut off of the compressor if the fire suppression system 
    of paragraph (b) is activated. A number of commenters suggested that 
    compressors should have an automatic shutdown feature that deenergizes 
    or shuts-off the compressor when the required fire suppression system 
    is activated. MSHA agrees. MSHA recognizes that under Sec. 75.1107-4 
    automatic deenergization is required if the automatic fire suppression 
    system is activated on unattended electrically powered compressors.
        Proposed paragraph (b)(2) has been omitted from the final rule. The 
    paragraph was intended to provide additional flexibility for compressor 
    installations located away from working sections and near a return air 
    course where a substantial pressure differential exists. No comments 
    were received in support of the proposed standard, while a number of 
    comments were received in opposition. Commenters objecting to the 
    standard raised concerns about overheating and stated that the 
    revisions were made unnecessary in view of modified paragraph (a). MSHA 
    agrees. Historically, when compressors that are on fire continue to 
    operate, they often released oil into the environment, thus increasing 
    the severity of the fire. For this reason, MSHA believes that safety is 
    best served by requiring compressors to be deenergized or shut-off when 
    the fire suppression system is activated. Commenters recommended 
    deenergization in (a)(2) of the final rule. MSHA agrees and has the 
    included automatic deenergization in (a)(2). One commenter suggested 
    that alarms be automatically given at the section and surface and that 
    two-way communications be provided at each compressor installation. 
    This recommendation has not been adopted since the rule provides the 
    desired level of safety through venting to the return, automatic fire 
    extinguishment and closure of doors, in addition to the alarms outside 
    the enclosure.
    
    Section 75.360  Preshift Examination
    
        The preshift examination is a critically important and fundamental 
    safety practice in the industry. It is a primary means of determining 
    the effectiveness of the mine's ventilation system and of detecting 
    developing hazards, such as methane accumulations, water accumulations, 
    and bad roof.
        A considerable number of comments were received representing a 
    range of opinions on the changes MSHA proposed. After consideration of 
    all comments received, the final rule 
    
    [[Page 9791]]
    adopts certain modifications and clarifications to the existing 
    standard to increase the effectiveness of the preshift examination. The 
    final rule removes paragraph (e), redesignates existing paragraphs (f) 
    through (h) as (e) through (g), revises paragraphs (a), (b), and (f) 
    and adds new paragraphs (b)(8) through (b)(10).
        Existing paragraph (a) is divided into paragraphs (a)(1)and (a)(2) 
    in the final rule. Paragraph (a)(1) of the final rule contains the 
    existing general requirement that preshift examinations are to be 
    conducted by certified persons designated by the operator. Paragraph 
    (a)(1) also modifies the existing and proposed language in response to 
    comments, to provide for preshift examinations at 8-hour periods. 
    Paragraph (a)(2) of the proposed rule would have allowed pumpers to 
    conduct an examination in lieu of the preshift examination under 
    certain conditions. The final rule adopts this approach with 2 changes. 
    The final rule does not require the pumper to examine for noncompliance 
    with mandatory safety and health standards that could result in a 
    hazardous condition and does require that records be made and retained 
    in accordance with Sec. 75.363.
        A number of commenters addressed the application of this standard 
    at mines where extended, overlapping, or other novel working shifts are 
    employed. MSHA agrees with commenters that evolution within the 
    industry in shift scheduling has presented a number of questions and 
    controversies regarding the standard which must be resolved to assure 
    that proper preshift examinations are conducted within suitable time 
    frames. Based on comments, the final rule adopts a modification to 
    clarify and standardize the application of the preshift examination in 
    recognition of the use of novel shifts while maintaining the protection 
    of the existing standard.
        Underground working schedules of three 8-hour shifts per day were 
    virtually standard when the previous rule was implemented. Currently a 
    substantial number of mining operations have work shifts of more than 8 
    hours. Other operations stagger or overlap shifts providing for 
    continuous underground mining activities. Some mines that operate 
    around the clock schedule persons to begin shifts at one-or two-hour 
    intervals. In such cases, controversies and misunderstandings have 
    developed regarding application of the current standard.
        Commenters suggested that preshift examinations should be conducted 
    for distinct 8-hour periods. Under this scenario a preshift examination 
    for an 8-hour period would be acceptable for the entire 8-hour period 
    regardless of shift schedules. Other comments indicate that this 
    suggested modification would be consistent with the original intent and 
    language of section 303(d)(2) of the Mine Act, which provides that no 
    person, other than certified persons designated to conduct the 
    examination, is permitted to enter any underground area unless a 
    preshift examination of such area has been made within 8 hours prior to 
    their entering the area. A commenter stated that to allow preshifts at 
    more than 8-hour periods reduces the protection envisioned by the 
    drafters of the Mine Act. MSHA understands the concerns and the 
    critical nature of the preshift examinations to monitor the constantly 
    changing conditions underground and has revised the rule accordingly to 
    provide for an examination at 8-hour intervals.
        Under the final rule, operators will establish the 8-hour periods 
    for which preshift examinations will be conducted. Persons may enter or 
    leave the mine, regardless of their shift schedule during any 
    established period for which a preshift examination has been conducted. 
    However, another preshift examination must be completed prior to the 
    next 8-hour period if any persons, other than examiners, remain in the 
    mine. As always, no person other than examiners may enter any 
    underground area prior to the completion of a preshift examination.
        The final rule requires three preshift examinations where persons 
    are underground for more than 16 hours per day. At mines with only one 
    8-hour shift per day only one preshift examination per day would be 
    required. Mines working 10-or 12- hour shifts would conduct preshift 
    examinations for each 8-hour period during which persons are 
    underground. MSHA agrees with comments that the original legislation of 
    the Mine Act envisioned that preshift examinations would be conducted 
    for each 8-hour interval that persons worked underground. Similar to 
    the existing requirement, the final rule does not require examinations 
    for designated 8-hour periods when no one goes underground.
        MSHA recognizes that the final rule may cause a limited number of 
    mines to perform examinations that are not currently required. These 
    affected mines do not operate 24 hours per day but work one or two 
    shifts which exceed 8 hours. For example, the final rule requires two 
    examinations per day at a mine operating one 12-hour shift per day. 
    When a mine operates two 10-hour shifts per day the final rule requires 
    three examinations per day. The Agency has concluded that, considering 
    the speed at which underground conditions can change, a reasonable 
    period must be identified after which another examination is necessary. 
    It is not MSHA's intent that the preshift be a continuous examination 
    without a beginning or an end. Rather if the mine uses regular shifts 
    that are longer than 8 hours in length, the preshift examination is 
    good for an entire 8-hour interval. Those persons who start their work 
    shift later than the normal shift start time do not need an additional 
    preshift examination during the remainder of the 8-hour period. 
    However, a preshift will be required if they are to stay in the area 
    past the end of the 8-hour period. However, in accordance with 
    longstanding practice, unplanned short excursions past the 8-hour 
    period that occur infrequently will be accepted without an additional 
    preshift. For example, miners required to stay an additional short 
    period of time, such as 15 minutes to complete a mechanical repair, or 
    due to a mantrip delay, would not need an additional preshift. The rule 
    simplifies and clarifies the application of the standard at mines 
    employing creative shift scheduling.
        Comments were received suggesting that the regulation should 
    stipulate 12:00 a.m., 8:00 a.m., and 4:00 p.m. as the beginning of the 
    8-hour periods for which preshift examinations would be required. This 
    suggestion has not been adopted. There is no safety or health benefit 
    to be gained through prohibiting operators from adopting other 8-hour 
    intervals, e.g., 10:00 p.m., 6:00 a.m., and 2:00 p.m. Also, the 
    standard is not intended to prevent operators from establishing their 
    own work times. For example, an operator may elect a starting time of 
    11:00 a.m. for a weekend project provided the preshift is completed 
    within the 3 hours prior to the beginning of the shift.
        A commenter suggested that the final rule not require a preshift 
    examination for non-coal producing shifts, where persons are to work in 
    the shaft, slope, drift, or on the immediate shaft or slope bottom 
    area. Under the commenter's suggestion, only that area immediately 
    surrounding the bottom would need to be examined. The rationale given 
    for the suggested change is that it is intended to bring the standard 
    into conformity with ``certain state regulatory programs''. MSHA is not 
    aware of state regulatory programs which would necessitate a change in 
    the language of the final rule. Additionally, because areas where 
    persons are not scheduled to work or travel are not required to be 
    examined under the final rule, the 
    
    [[Page 9792]]
    change is unnecessary. Therefore, the suggestion of the commenter has 
    not been adopted.
        Paragraph (a)(2) of the final rule provides that preshift 
    examinations of areas where pumpers are scheduled to work or travel are 
    not required prior to the pumper entering the areas, if the pumper is a 
    certified person and the pumper conducts the specified examinations. 
    This standard recognizes that pumpers travel to remote areas of the 
    mine to check on water levels and the status of pumps, making regular 
    preshift examinations impractical. The examinations required by pumpers 
    include an examination for hazardous conditions, tests for methane and 
    oxygen deficiency, and a determination of whether the air is moving in 
    its proper direction in the area where the pumper works or travels. The 
    examination of the area must be completed before the pumper performs 
    any other work. A record of all hazardous conditions found by the 
    pumper must be made and retained in accordance with Sec. 75.363.
        One commenter objected to the proposal stating that areas where 
    pumpers work or travel should be preshift examined. The commenter 
    stated that the proposed revision would weaken the protections provided 
    under the existing standard, and that the rule would indirectly require 
    that pumpers be certified. The commenter noted that most pumpers are 
    not certified to perform examinations, and that it would be 
    inappropriate to require ``hourly employees'' to obtain such 
    certifications. The commenter further suggested that the proposed 
    revision could infringe on the traditional relationship between labor 
    and management wherein only management is required to be certified. The 
    final rule does not require that pumpers be certified. Rather the final 
    rule provides an option for pumpers to perform examinations for 
    themselves if they are certified. Otherwise, areas where pumpers are 
    scheduled to travel must be preshift examined by a certified person.
        The final rule maintains the existing level of safety. A complete 
    examination by a certified person is still required and the examination 
    will be conducted closer to the time that work is performed in the 
    area. As with other examination requirements, no one may accompany the 
    pumper during the examination. It is important to note that the 
    examination performed by the pumper under paragraph (a)(2) is not 
    acceptable if other persons have been scheduled to enter the area. The 
    pumper may only perform an examination in lieu of a preshift for 
    himself or herself. If, however, after the beginning of the preshift 
    examination, persons are assigned to enter the area, the pumper may 
    perform a supplemental examination for other persons in accordance with 
    Sec. 75.361, provided that the certified pumper is designated by the 
    operator to conduct such examinations.
        Commenters asserted that pumpers cannot conduct quality 
    examinations and effectively perform their normal work duties. Under a 
    previous standard replaced in 1992, persons such as pumpers, who were 
    required to enter idle or abandoned areas on a regular basis in the 
    performance of their duties, and who were trained and qualified, were 
    authorized to make examinations for methane, oxygen deficiency and 
    other dangerous conditions for themselves. Under the final rule, either 
    a preshift examination must be made in accordance with paragraph (a)(1) 
    before a pumper enters an area, or certified pumpers must conduct an 
    examination under paragraph (a)(2).
        One commenter cited a 1984 incident at the Greenwich No. 1 mine 
    where three miners were killed in an explosion while entering an idle 
    area to work on a pump. The commenter suggested that an effective 
    preshift examination would have prevented the accident and suggests 
    that both a preshift examination and examinations by qualified pumpers 
    should be required. An adequate preshift examination or supplemental 
    examination as specified in the final rule, would prevent a similar 
    result. One of these two examinations is always required under the 
    final rule before persons enter any such idle area.
        Also in addressing paragraph (a)(2), one commenter suggested that 
    some certified persons who are pumpers may not conduct adequate 
    examinations. According to the commenter, certified persons conducting 
    examinations under paragraph (a)(2) cannot be expected to perform at 
    the same level as preshift examiners conducting examinations under 
    (a)(1). MSHA expects that all certified persons who are required to 
    conduct examinations, including certified pumpers, will conduct the 
    examinations in accordance with the standards.
        Another commenter suggested that persons performing other jobs, 
    such as rock dusters, should be permitted to perform examinations for 
    themselves. Pumpers, unlike most other miners except mine examiners, 
    travel in remote areas of the mine and normally work alone. Persons 
    performing work such as rock dusting, however, normally work in newer 
    areas of the mine where mining has only recently been completed and 
    normally work as a part of a crew. Therefore, MSHA does not consider 
    the work assignments to be similar enough to merit the same 
    consideration and has not included this recommendation in the final 
    rule.
        As proposed, paragraph (a)(2) would have required that the 
    certified pumper examine for noncompliance with mandatory safety or 
    health standards that could result in a hazardous condition, test for 
    methane and oxygen deficiency, and determine if the air is moving in 
    its proper direction in the area to be worked or traveled by the 
    pumper. A number of commenters recommended the deletion of the 
    requirement that the certified pumper identify and record noncompliance 
    with mandatory safety and health standards that could result in a 
    hazardous condition. Commenters cited a number of objections: the 
    requirement would detract from miner safety, would significantly and 
    unnecessarily increase the burden on examiners, would diminish the 
    quality of the examination, would require excessive judgment and 
    discretion by the examiners, and require examiners to make predictions. 
    After considering all submitted comments, MSHA concludes that these 
    comments have merit and the final rule does not require certified 
    pumpers to examine for violations of mandatory safety and health 
    standards that could result in a hazardous condition.
        Under paragraph (a)(2), a record of all hazardous conditions found 
    by the pumper must be kept in accordance with Sec. 75.363. One 
    commenter objected in that all of the records resulting from a preshift 
    examination would not be required of the pumper, such as the locations 
    of air and methane measurements and the results of methane tests. The 
    commenter suggested that the full preshift record should be produced 
    just as if the examination were done according to paragraph (a)(1). In 
    the case of the pumper-examined area, the records required under 
    paragraph (a)(2) will assure that mine management is made aware of any 
    condition which results in a hazardous condition and will facilitate 
    corrective actions being taken. It is important to note that the pumper 
    is conducting an examination in a limited area only for himself or 
    herself. This is in contrast to the various areas addressed in 
    paragraph (a)(1), where the examination is in anticipation of one or 
    many other miners entering these areas usually on a regular basis, all 
    of whom are relying on the examiner's findings. In these circumstances, 
    it is important that a record is made which can be 
    
    [[Page 9793]]
    utilized to spot ongoing problems and trends.
        Paragraph (b) of the rule specifies the nature of the preshift 
    examinations and the locations where a preshift examination is 
    required. Proposed paragraph (b) would have required that the person 
    conducting the preshift examination would examine for noncompliance 
    with mandatory safety or health standards that could result in a 
    hazardous condition. After considering all submitted comments, the 
    final rule does not contain this requirement.
        A number of commenters recommended the deletion of the requirement 
    to identify and record noncompliance with mandatory safety and health 
    standards that could result in a hazardous condition. Various 
    commenters stated that the proposed requirement: would distract the 
    examiner from the most important aspects of the preshift examination; 
    would require predictions; would be an unrealistic expectation; and/or 
    is designed only to facilitate enforcement actions. Commenters also 
    suggested that the proposal would result in a shift in the focus of 
    preshift examination from true hazards to noncompliance.
        Other commenters objected that the proposed requirement to examine 
    for noncompliance with mandatory safety or health standards that could 
    result in a hazardous condition is so vague that it could detract from 
    miner safety. One commenter suggested that the examiners would spend 
    their time performing permissibility checks, torquing roof bolts, 
    measuring roof bolt spacing, and similar tasks which represent a 
    significant departure from the examiners traditional duties.
        Another commenter expressed the opinion that paragraph (b) should 
    require that all violations of mandatory safety or health standards be 
    recorded and it should not be limited to those that could result in 
    hazardous conditions. Preshift examinations assess the overall safety 
    conditions in the mine; assure that critical areas are properly 
    ventilated; assure that the mine is safe to be entered by miners on the 
    oncoming shift; identify hazards, whether violations or not, for the 
    protection of miners; and through this identification facilitate 
    correction of hazardous conditions.
        The preshift examination requirements in the final rule are 
    intended to focus the attention of the examiner in critical areas. This 
    approach is consistent with the fundamental purpose of preshift 
    examinations which is to discover conditions that pose a hazard to 
    miners. MSHA is persuaded that to require examiners to look for 
    violations that might become a hazard could distract examiners from 
    their primary duties. The final rule, therefore, does not adopt this 
    aspect of the proposal.
        Paragraph (b)(1) of the final rule adopts the proposal and 
    clarifies that preshift examinations are to include travelways in 
    addition to roadways and track haulageways. During informational 
    meetings, commenters indicated that the terms ``roadways'' and ``track 
    haulageways'' are associated with areas where mobile powered equipment 
    is operated. By including the term ``travelways,'' the rule clarifies 
    that areas where persons are scheduled to travel on foot are to be 
    included, since hazards may also develop in these areas.
        One commenter suggested that the proposal would greatly increase 
    the area that must be preshift examined, even though the requirement is 
    limited to only those travelways where miners are scheduled to work or 
    travel. This commenter suggested that in large mines many more areas 
    than would actually be used by miners would have to be preshift 
    examined. The premise of the preshift examination is that all areas 
    where miners will work or travel be examined for hazards. The final 
    rule change concerning ``travelways'' is intended only to clarify that, 
    when miners are scheduled to use these areas, they must be preshift 
    examined first. The final rule, therefore, does not expand the existing 
    scope to the preshift examination requirements.
        The language of the existing paragraph (b)(1) referring to, ``* * * 
    other areas where persons are scheduled to work or travel during the 
    oncoming shift'' is transferred to a new paragraph (b)(10) with 
    conforming changes, as proposed. MSHA received no comments on moving 
    this provision to paragraph (b)(10). Commenters did respond to the 
    phrase in proposed paragraph (b)(1) requiring preshift examinations of 
    roadways, travelways and track haulageways where persons are ``* * * 
    scheduled, prior to the beginning of the preshift examination to work 
    or travel during the oncoming shift.'' The purpose of this proposal, 
    which is adopted in the final rule with only clarifying changes, is to 
    permit work and mining personnel to be rescheduled after the start of a 
    shift. Preshift examinations, by their nature, must be completed before 
    the start of the shift. Changes in conditions, however, such as a 
    breakdown of equipment, can alter planned work schedules. To 
    accommodate these circumstances, the final rule requires mine operators 
    to design preshift examinations around the best information available 
    at the time the preshift begins. If changes must be made, Sec. 75.361 
    specifies that areas not preshift examined be covered by a supplemental 
    examination performed by certified persons before miners enter the 
    area.
        One commenter objected that was confusing and should be modified. 
    Other commenters foresaw possible abuses of the flexibility offered by 
    the rule with some operators performing supplemental rather than 
    preshift examinations, claiming that assignments were made after the 
    preshift examination begins. After considering the comments, MSHA has 
    retained the proposed flexibility to preshift examine areas where 
    miners are scheduled to work or travel. To require more than this would 
    be impractical.
        Section 75.360(b)(3) of the final rule requires preshift 
    examinations of working sections and areas where mechanized mining 
    equipment is being installed or removed if anyone is scheduled to work 
    on the section or in the area during the oncoming shift. A discussion 
    of the reproposal of provisions concerning the installation and removal 
    of mechanized mining equipment is presented in the General Discussion 
    section of this preamble. As with the existing rule, the examination 
    includes working places, approaches to worked-out areas, and 
    ventilation controls on these sections or in these areas. The final 
    rule, like the proposal, adds a new requirement that the examination 
    also include a test of the roof, face and rib conditions on these 
    sections or in these areas.
        Proposed changes to paragraph (b)(3) not adopted in the final rule 
    would have also required preshift examination of sections not scheduled 
    to operate but capable of producing coal by simply energizing the 
    equipment on the section. Also, proposed changes to paragraphs (c), 
    (c)(1), and (c)(3) specifying where air volume measurements were to be 
    taken on these sections have also not been adopted in the final rule.
        The new requirement to test the roof, face and rib conditions is 
    added because of the importance of this test to the safety of miners. 
    In newly mined areas, checking roof, face and rib stability is most 
    important to preventing injuries and death. Comments were received in 
    support of the revision, citing accidents which might have been 
    prevented had such tests been adequately performed during preshift 
    examinations. One commenter, when suggesting new wording for paragraph 
    (b)(3), indicated that the requirement to test the roof, face and rib 
    conditions should be deleted but 
    
    [[Page 9794]]
    did not offer any rationale for the suggested deletion. Another 
    commenter suggested that the preshift examination should only require a 
    visual examination of the roof, rather than a physical examination. 
    Physical examinations of the roof, such as ``sounding,'' have been a 
    historically accepted method for examiners to test roof competency. 
    Whenever an examiner has a question as to whether a section of roof is 
    competent, such a test should be performed.
        Comments were mixed on MSHA's proposed revision to include idle 
    working sections as part of the preshift examination. The proposal is 
    not retained in the final rule. Some commenters objected to the 
    proposal as unnecessary, burdensome, or impractical. Commenters 
    believed that the existing Sec. 75.361 requirement for supplemental 
    examinations prior to anyone entering into such an area was sufficient. 
    Commenters also stated that a preshift examination in these areas could 
    introduce a false sense of security and that the effect would be to 
    divert preshift examiners from more important duties. One commenter 
    stated that the proposed requirement would be inconsistent with and 
    contradictory to the basic concept of preshift examinations. Another 
    commenter objected to MSHA's statement in the preamble to the proposal 
    that there is a reasonable likelihood that miners will at some point 
    during a working shift enter sections that are set up to mine coal.
        In support of the proposed requirement to preshift examine idle 
    sections, one commenter cited explosions at the Red Ash Mine in 1973, 
    the Scotia Mine in 1976, the P&P Mine in 1977, the Ferrell #17 in 1980, 
    the Greenwich #1 Mine in 1984, and the 1994 explosion at the Day Branch 
    No. 9 Mine in Kentucky. As the commenter pointed out, in each of these 
    accidents miners were sent into an area that had not been preshift 
    examined. However, none of these accidents were the result of miners 
    entering areas that would have been covered by the proposal. In each 
    instance, miners entered an area where mining had ceased, but could not 
    be resumed by simply energizing equipment. Another common thread in 
    each of these explosions was the failure of the operator to conduct the 
    required supplemental examination prior to miners entering the area on 
    an unscheduled basis.
        Paragraph (b)(4) of the final rule requires preshift examinations 
    to include approaches to worked-out areas along intake air courses and 
    at the entries used to carry air into worked-out areas if the intake 
    air passing the approaches is used to ventilate working sections where 
    anyone is scheduled to work during the oncoming shift. The examination 
    of the approaches to the worked-out areas is to be made in the intake 
    air course immediately inby and outby each entry used to carry air into 
    the worked-out area. The examination of the entries used to carry air 
    into the worked-out areas is to be at a point immediately inby the 
    intersection of each entry with the intake air course. The standard is 
    intended to assure that miners are not exposed to the hazards 
    associated with ventilating working sections with contaminated air 
    which has passed through a worked-out area. The requirement is 
    consistent with the Sec. 75.301 definition of ``return air'' and with 
    Sec. 75.332 which provides that working sections and other specified 
    areas must be ventilated with intake air.
        Commenters correctly noted that a clarification was needed in the 
    first sentence of proposed paragraph (b)(4) to indicate that the 
    examination at the specified points is only required if the intake air 
    passing the approaches is used to ventilate working sections where 
    anyone is scheduled to work during the oncoming shift. Commenters 
    suggested that an examination should not be required if the intake air 
    is not used to ventilate working sections or if no one is scheduled to 
    work on the section. This was the result intended by the proposal and 
    the final rule has been revised accordingly.
        One commenter also suggested that the requirement in paragraph 
    (b)(4) is unnecessary because the safeguards in the approved mine 
    ventilation plan should prevent an air reversal in a worked-out area in 
    which this air would enter the intake air course. The commenter offered 
    the example of a worked-out area connected directly to a bleeder 
    system. MSHA agrees that when proper safeguards are in place and 
    operating as intended, air reversals are unlikely. However, roof falls 
    and other obstructions in the worked-out area or in the bleeder can 
    cause air reversals, permitting return air to enter the intake and be 
    transported to the working section. Without a suitable examination, 
    this condition would go undetected and could lead to disaster. While 
    not exactly the same, the explosion at the Pyro Mine in 1989, which 
    resulted in the deaths of 10 miners, was the result of a somewhat 
    similar set of circumstances. A water blockage in the bleeder entry 
    that combined with changes to certain ventilation controls led to 
    methane migrating from the worked-out area onto the longwall face. 
    MSHA's report of this accident concludes, in part, that changes that 
    occurred during the mining of the longwall panel and in the bleeder 
    entries caused a fragile balance of air flows to exist in the 
    ventilation system that permitted methane to migrate from the gob and 
    to accumulate near the longwall headgate.
        One commenter agreed with the proposal and discussed the need to 
    assure that miners are not exposed to the hazards associated with 
    ventilating working sections with return air.
        Essentially, the final rule requires that at each applicable 
    approach, three examinations must be made; immediately inby and outby 
    the approach in the intake entry and in the approach itself immediately 
    inby the intersection with the intake entry. Situations exist where 
    multiple openings along an intake lead into a worked-out area. Under 
    some conditions intake air enters the upstream openings, passes through 
    the worked-out area, and then re-enters the intake. The examination 
    required by paragraph (b)(4) is designed to assure that such a 
    condition is detected. Also, the examination detects any change in 
    ventilation entering the worked-out area which may warrant follow-up or 
    corrective actions to assure that the worked-out area is ventilated.
        Paragraph (b)(6) of the final rule adopts the proposal modifying 
    the existing rule. No comments were received on this aspect of the 
    proposal. The final rule in paragraph (b)(6)(i) requires preshift 
    examinations to include entries and rooms developed after November 15, 
    1992 (the effective date of the existing rule), and developed more than 
    2 crosscuts off an intake air course without permanent ventilation 
    controls where intake air passes through or by these entries or rooms 
    to reach a working section where anyone is scheduled to work during the 
    oncoming shift. Similarly, under (b)(6)(ii) the examination must 
    include entries and rooms developed after November 15, 1992, and driven 
    more than 20 feet off an intake air course without a crosscut and 
    without permanent ventilation controls where intake air passes through 
    or by these entries or rooms to reach a working section where anyone is 
    scheduled to work during the oncoming shift.
        Existing paragraph (b)(6) requires that a preshift examination be 
    made in all entries and rooms driven more than 20 feet off an intake 
    air course without a crosscut or more than 2 crosscuts off an intake 
    air course without permanent ventilation controls where intake air 
    passes through or by these entries or rooms to a working section where 
    anyone is scheduled to work during the oncoming shift. MSHA proposed 
    
    [[Page 9795]]
    modifications to existing paragraph (b)(6) based on concerns raised 
    following publication of the existing rule on May 15, 1992. Commenters 
    at that time indicated that extensive rehabilitation would be required 
    at a number of mines to implement the standard in the rooms and entries 
    described in the rule, causing diminished safety for miners performing 
    the rehabilitation work. Commenters noted that some areas had been 
    timbered heavily and cribbed because of adverse roof conditions and 
    that rehabilitation would unnecessarily expose miners to roof falls and 
    rib rolls while removing or repositioning roof support. In addition, 
    roof conditions in some areas would remain hazardous even after 
    rehabilitation. The commenters also noted that many such areas had been 
    in existence for many years without incident and that any methane 
    liberation had long since stopped due to the passage of time. They 
    noted that some areas cannot be effectively sealed and that the risks 
    associated with rehabilitation and subsequent physical examinations 
    would greatly outweigh the safety benefit to be gained. MSHA recognizes 
    the legitimate concerns raised by the commenters and the final rule 
    requires preshift examination of entries and rooms developed after 
    November 15, 1992 and driven more than 20 feet off an intake air course 
    without a crosscut or more than 2 crosscuts off an intake air course 
    without permanent ventilation controls where intake air passes through 
    or by these entries or rooms to a working section where anyone is 
    scheduled to work during the oncoming shift. MSHA believes, however, 
    that the conditions addressed by paragraph (b)(6) are the result of 
    improper mining practices in the past. These mining systems should be 
    revised in the future to avoid poor conditions, or the areas affected 
    should be fully and reliably ventilated and be examined. Also, the 
    final rule applies only to entries and rooms developed after the 
    effective date of the existing rule. As such, the mining industry was 
    on notice of the shortcomings of mining practices that left entries and 
    rooms of the type addressed by the standard.
        Paragraph (b)(8) retains the proposal requiring preshift 
    examinations to include high spots along intake air courses where 
    methane is likely to accumulate, if equipment may be operated in the 
    area during the shift. As noted in the proposal, it has long been 
    recognized that methane can accumulate in high areas with no 
    indications being detected in the lower portions of the opening. As 
    mobile equipment passes under these areas or a conveyor belt is put 
    into operation, the methane is pulled down and mixed with the air in 
    the entry and may be ignited. The final rule addresses the hazards of 
    undetected accumulations of methane in high spots by requiring preshift 
    examinations in such areas in intake air courses if equipment will be 
    operated in the area during the shift.
        Several commenters requested that MSHA clarify the term ``high 
    spots.'' One commenter stated that many hours would be necessary to 
    examine every indentation in the roof of a large mine and stated the 
    belief that the turbulence created by passing equipment would render 
    harmless any of the small amounts of methane that might possibly 
    accumulate. Another commenter believed the requirement was unnecessary 
    because there has never been a problem with methane accumulating in 
    intakes in quantities sufficient to cause an explosion. One commenter 
    suggested that the requirement should only be applicable to mines with 
    a demonstrated history of methane accumulations, noting that although 
    mines are considered likely to liberate methane, it is not likely that 
    all mines will accumulate methane in high spots.
        Another commenter suggested that preshift examinations should be 
    required in all high spots in intakes, returns, belt entries, and track 
    haulage entries. The commenter also objected to limiting the 
    examination in intakes only to areas where equipment may be operated 
    during the shift. The commenter observed that methane can accumulate 
    quickly in high spots and that it is critical to detect the methane 
    before it creates a danger. The commenter notes several accidents 
    involving methane accumulations in high spots, including: Meigs No. 31 
    Mine in 1993 where methane in a roof cavity was ignited by a torch; VP-
    5 Mine in 1992 when methane in a cavity was ignited by a torch; Ferrell 
    No. 17 Mine in 1980 where, according to the commenter, methane may have 
    accumulated in a cavity in the belt entry roof and may have been 
    ignited by a trolley powered vehicle; and in the VP-6 in 1982 where 
    methane in a high spot was ignited by a trolley powered vehicle 
    traveling through the area. The commenter stated that accumulations of 
    methane in high spots can be ignited by any number of sources.
        A meaningful preshift examination requires that conditions which 
    can lead to an explosion or ignition be detected and corrected before 
    miners begin their work. In addition to the accidents cited above 
    attributed to methane accumulations in high spots, the Itmann No. 3 
    Mine explosion occurred when a trolley powered vehicle ignited methane 
    in a high spot, resulting in the death of 5 miners and severe burns to 
    2 other miners. The phrase ``high spots where methane is likely to 
    accumulate'' should be understood in the coal mining industry. 
    Experienced miners, and in particular preshift examiners and certified 
    persons, can readily recognize a high spot where methane is likely to 
    accumulate. Also, MSHA for many years has considered preshift 
    examinations to be inadequate where examinations did not include 
    methane tests in these areas. An examination of ``every indentation,'' 
    as foreseen by one commenter is not expected nor intended by paragraph 
    (b)(8), which specifies that preshift examinations be used to identify 
    methane hazards by testing in the appropriate locations. The final rule 
    does not adopt the suggestion that methane examinations be based on 
    mine liberation history since significant methane liberation may begin 
    or can greatly increase at any time. Also, the potential for a 
    dangerous accumulation of methane in a high spot is influenced by mine 
    ventilation, particularly the air velocity in the entry.
        One commenter suggested that the rule require tests only in 
    ``unventilated high spots'' along intake air courses. The final rule 
    does not adopt this approach. The purpose of the preshift examination 
    is to detect hazards, in this case accumulations of methane. Nominal 
    ventilation in a high roof cavity may not be sufficient to sweep away 
    methane and an accumulation could exist. The final rule directs an 
    examiner's attention to such situations.
        Proposed paragraph (b)(9) is modified in the final rule. Paragraph 
    (b)(9) of the final rule requires preshift examinations at underground 
    electrical installations referred to in Sec. 75.340(a), except those 
    water pumps listed in Sec. 75.340(b)(2) through (b)(6), and areas where 
    compressors subject to Sec. 75.344 are installed if the electrical 
    installation or compressor is or will be energized during the shift. 
    The proposal would have exempted all water pumps from the requirements 
    of paragraph (b)(9).
        One commenter objected to the exemption for pumps and recommended 
    that all pumps be examined pointing out that some pumps are large, 
    high-horsepower units. The commenter noted a 1994 case in Virginia 
    where a 200 horsepower pump exploded. Pumps of this type may be in 
    locations or in applications that would not be examined by pumpers 
    under paragraph (a)(2). The final rule responds 
    
    [[Page 9796]]
    to this issue by requiring that all pumps should not be exempted from 
    the standard. Paragraph (b)(9) requires preshift examinations of all 
    pumps, except those specified in Sec. 75.340(b)(2) through (b)(6). 
    Pumps specified in Sec. 75.340(b)(2) through (b)(6) and other pumps 
    that operate automatically or that otherwise may be energized are 
    generally in the more remote areas of the mine and are to be examined 
    weekly in accordance with Sec. 75.364.
        Pumps which will be examined by certified pumpers in accordance 
    with paragraph (a)(2) are not covered by the final rule because of the 
    limited hazards they pose and because certified pumpers would 
    themselves conduct examinations of this equipment in accordance with 
    paragraph (a)(2). Examinations by pumpers at these locations will 
    assure that methane has not accumulated and that the equipment is not 
    in a condition to create a fire or ignition source.
        A review of the accident history reveals a number of fires in 
    equipment that, under the final rule, would be subject to preshift 
    examinations. For example, the compressor that MSHA identified as the 
    probable cause of the fire in the Wilberg Mine, which killed 28 miners, 
    would have required a preshift examination under (b)(9) of the final 
    rule. Additionally, MSHA has identified several fires associated with 
    rectifiers and transformer installations in the mining industry. One of 
    these transformer fires was discovered during a preshift examination.
        One commenter supported proposed paragraph (b)(9) and noted a 
    number of ignitions involving trolleys. The commenter also noted that 
    history demonstrates that other electrical installations present 
    ignition or fire hazards which should be examined before each shift.
        One commenter incorrectly understood proposed paragraph (b)(9) to 
    not require preshift examinations of areas where compressors subject to 
    Sec. 75.344 are installed if the compressor is or will be energized 
    during the shift. The standard does require preshift examinations of 
    such equipment, which includes all compressors except those which are 
    components of equipment such as locomotives and rock dusting machines 
    and are compressors of less than five horsepower.
        Paragraph (b)(10) adopts the proposal that preshift examinations 
    include other areas where work or travel during the oncoming shift is 
    scheduled prior to the beginning of the preshift examination. This 
    provision recognizes that work requirements and situations may change 
    after the preshift examination has begun. Often, once the examination 
    has started it is not possible to contact the examiners to direct them 
    to newly identified areas where miners will work. In these cases, a 
    supplemental examination is required before persons work or travel in 
    these areas. As discussed in the preamble to the proposal, paragraph 
    (b)(1) requires preshift examinations of any underground area where 
    persons are scheduled to work or travel during the oncoming shift. 
    Under the existing rule, an operator did not have the flexibility to 
    modify work assignments after the preshift examination had begun, 
    unless it was possible to contact and redirect the examiners to perform 
    a preshift examination before the beginning of the shift. Commenters in 
    general supported the proposal. One commenter, however, while 
    supporting the change expressed concern that the provision could be 
    abused. MSHA does not anticipate abuse of the rule and believes it to 
    be a reasonable approach to assuring that areas where persons work or 
    travel are examined.
        As discussed above, the final rule does not adopt the proposed 
    revisions to paragraphs (c), (c)(1), and (c)(3) and instead retains the 
    language of the existing standard. While commenters to proposed 
    paragraphs (c), (c)(1), and (c)(3) objected to expanding air volume 
    measurements made during preshift examinations to sections where coal 
    could be mined by simply energizing the equipment, no comments were 
    received objecting to retaining the requirement for areas where 
    equipment is being installed or removed. An in-depth discussion of the 
    reproposal of provisions concerning the installation and removal of 
    mechanized mining equipment is presented in the General Discussion 
    section of this preamble.
        Paragraph (f) of the final rule sets out the requirements for 
    recording and countersigning both the results of the preshift 
    examination and actions taken to correct hazardous conditions found 
    during the preshift examination. The final rule adopts the following 
    proposed revisions to the existing rule: a record of the results of the 
    preshift examination is required to be made; the results of methane 
    tests are required to be made in terms of the percentage of methane 
    found; and a certified person is required to record the actions taken 
    to correct hazardous conditions found during the preshift examination.
        Additionally, paragraph (f) of the proposal would have required 
    countersigning by both the mine foreman and the superintendent or 
    equivalent individual to whom the mine foreman reports. The final rule 
    does not require this second level countersigning. Also, the final rule 
    allows an official equivalent to a mine foreman to sign the records. 
    Finally, the final rule allows for secure storage of records in a way 
    that is not susceptible to alteration and the records can be kept in a 
    book or in a computer system.
        Commenters suggested that the final rule only require the examiner 
    to record uncorrected hazardous conditions and not those which were 
    corrected by the end of the shift. Commenters characterized the 
    reporting of corrected hazardous conditions as unnecessary and 
    unjustified by the accident history.
        MSHA did not adopt the proposal to record corrected defects found 
    during the fan examination required by Sec. 75.312. MSHA believes, 
    however, that a record of all hazards found during the preshift 
    examination, including those corrected, is necessary. The record serves 
    as a history of the types of conditions that are being experienced in 
    the mine. When the records are properly completed and reviewed, mine 
    operators can use them to determine if the same hazardous conditions 
    are occurring repeatedly and if the corrective action being taken is 
    effective. Additionally, this record can permit mine management, the 
    representative of miners, and the representative of the Secretary to 
    better focus their attention during examinations and inspections. The 
    safety value of a complete record is illustrated by the 1989 explosion 
    at Pyro Mining Company's William Station Mine in which 10 miners were 
    killed. MSHA's accident investigation report concludes that methane 
    concentrations of up to 6.5 percent were detected in the explosion area 
    prior to the explosion but reports by the mine foreman for the shift 
    failed to record the presence of these dangerous accumulations of 
    methane or show the action taken to correct the condition. The 
    investigation further found that the failure to record these methane 
    accumulations in the appropriate record books prevented management 
    officials and other interested persons from learning of the hazardous 
    condition and initiating corrective action. In light of the record, the 
    final rule adopts the proposal and requires the examiner to record the 
    results, whether corrected or not, of the preshift examination and the 
    action taken to correct hazardous conditions found during the preshift 
    examination. This would include hazardous conditions and their 
    locations and the results of methane and air measurements required to 
    be made elsewhere in Sec. 75.360. 
    
    [[Page 9797]]
    
        As with other records required by this rule, the records of 
    preshift examinations may be kept either in secure books that are not 
    susceptible to alteration or electronically in a computer system so as 
    to be secure and not susceptible to alteration. A detailed discussion 
    of record books and the use of computers to maintain records can be 
    found in the General Discussion of this preamble.
        A variety of comments were received regarding the countersigning of 
    preshift records by the mine foreman, and the time permitted for 
    countersigning. The final rule adopts the proposal that the mine 
    foreman or equivalent mine official must countersign the record of the 
    preshift examination by the end of the mine foreman's next regularly 
    scheduled working shift. The mine foreman is in a position of 
    responsibility for the day-to-day operation of the mine. It is 
    essential for the health and safety of the miners that the mine foreman 
    be fully aware of the information contained in the preshift examination 
    reports so as to be able to allocate resources to address safety 
    problems. Allowing until the end of the mine foreman's next regularly 
    scheduled working shift to countersign the reports provides sufficient 
    flexibility to make compliance practical while assuring that the mine 
    foreman is aware of the results of the examination in a reasonably 
    timely manner.
        Some commenters suggested that the time for countersigning is 
    unnecessarily long, and that the final rule should restore a previous 
    requirement that countersigning be completed ``promptly.'' The term 
    ``promptly'' involves ambiguity that is eliminated by specifying the 
    time for countersigning the preshift examination record. The rulemaking 
    record does not show that the time set by the final rule would expose 
    miners to safety or health risks. Commenters suggested that the term 
    ``mine foreman'' be replaced by a ``certified person responsible for 
    ventilation of the mine or his designee.'' Another commenter suggested 
    that the record could be countersigned by the mine foreman or any other 
    mine official responsible for the day-to-day operation of the mine. 
    Commenters stated that some operations no longer use the terms ``mine 
    foreman,'' ``mine manager,'' or ``superintendent''. To provide for 
    alternative management titles, the final rule incorporates the phrase 
    ``or equivalent mine official.''
        Numerous comments were received regarding the proposal for second 
    level countersigning of the preshift examination record by the mine 
    superintendent, mine manager, or other mine official to whom the mine 
    foreman is directly accountable, within 2 scheduled production days 
    after the countersigning by the mine foreman. The final rule does not 
    retain this proposed requirement. A detailed discussion of the subject 
    of second level countersigning can be found in the General Discussion 
    section of this preamble.
        Paragraph (f) of the final rule also contains revisions to the 
    existing rule to allow for electronic storage of records. Paragraph (g) 
    requires that the records required by Sec. 75.360 be maintained at a 
    surface location at the mine for one year and be made available for 
    inspection by authorized representatives of the Secretary and the 
    representatives of miners. A discussion of comments concerning the use 
    of computers to maintain records can be found in the General Discussion 
    of this preamble.
    
    Section 75.362  On-Shift Examination
    
        Like the preshift examination, the on-shift examination of working 
    sections is a long accepted safety practice in coal mining. As coal is 
    extracted, conditions in the mine continually change and hazardous 
    conditions can develop. Because the mining environment changes 
    constantly during coal production, this examination identifies emerging 
    hazards or verifies that hazards have not developed since the preshift 
    examination. Generally, the on-shift examination includes tests for 
    methane and oxygen deficiency, an examination for hazardous conditions, 
    and air measurements at specified locations.
        The final rule adopts proposed Sec. 75.362 with the exception that 
    revisions have been made to the proposed provisions dealing with an 
    examination for compliance with the mine ventilation plan requirements 
    for respirable dust control.
        The final rule redesignates existing (d)(1)(i) and (ii) as 
    (d)(1)(ii) and (iii), revises paragraphs (a)(1), (c)(1), (d)(1)(iii) 
    and (d)(2), removes paragraph (a)(2), and adds new paragraphs (a)(2) 
    and (d)(1)(i). Additionally, the requirements of existing paragraphs 
    (g) and (h), recordkeeping and retention, are transferred to 
    Sec. 75.363, Hazardous conditions, posting, correcting, and recording. 
    New paragraphs (g)(1) and (g)(2) are also added by the final rule.
        The word ``on-shift'' has been added to the first sentence of 
    paragraph (a)(1) for clarity and consistency with other paragraphs of 
    Sec. 75.362. MSHA did not receive any comments on this proposed 
    revision. Paragraph (a)(1) is also revised as proposed to require a 
    certified person designated by the operator to conduct an on-shift 
    examination of each section where anyone is assigned to work during the 
    shift and any area where mechanized mining equipment is being installed 
    or removed during the shift. The existing rule required that an on-
    shift examination be performed only on sections where coal is produced 
    and areas where mechanized mining equipment is being installed or 
    removed. Some commenters agreed that many of the same hazards exist on 
    a section whether coal is being produced or not. Commenters gave 
    several examples of activities that take place on non-coal producing 
    sections including equipment repair and maintenance, cutting and 
    welding, rockdusting, clean-up, and roof bolting. As indicated by these 
    commenters, all of these activities present the potential for a serious 
    accident. One commenter arguing against the proposed change stated that 
    the preshift and supplemental examinations already address the safety 
    concerns to which the proposal was directed. While MSHA considers the 
    preshift and supplemental examinations to be of great importance in 
    providing a safe work environment, these examinations are performed 
    prior to workers on a shift entering the mine or, in the case of the 
    supplemental examination, in an area of the mine that has not been 
    preshift examined. The on- shift examination is intended to address 
    hazards that develop during the shift. The concept of the on-shift 
    examination is not new. On-shift examinations of coal producing 
    sections have been required since the enactment of the Federal Coal 
    Mine Health and Safety Act of 1969.
        Another commenter arguing against expanding the on-shift 
    examination requirement to non-coal producing sections stated that 
    requiring on-shift examinations of areas other than working sections 
    would detract from other required examinations. On-shift examinations 
    on coal producing sections are normally conducted by section foremen 
    who spend the vast majority of the shift on the section they are 
    supervising. These individuals will not normally conduct the on-shift 
    examinations in non-coal producing sections. These examinations will be 
    conducted by certified persons assigned to work in these areas or other 
    certified persons assigned to conduct these examinations. MSHA does 
    not, therefore, foresee reduced attention to examinations in working 
    sections.
        Another commenter suggested that the requirements for on-shift 
    examinations be expanded further than proposed. The commenter stated 
    that many of the same types of activities that 
    
    [[Page 9798]]
    occur on non-production shifts on the sections also occur in outby 
    areas of mines. In support of this recommendation the commenter pointed 
    to 4 explosions which occurred in outby areas of the mines. Those 
    accidents were the explosions at the Greenwich Collieries No. 1 Mine in 
    Pennsylvania in February 1984 where 3 miners were killed; the explosion 
    at the Day Branch Mine in Kentucky in 1994 where 2 miners lost their 
    lives and; an ignition at the Loveridge No. 22 Mine in West Virginia in 
    1992 that burned 1 miner. In each accident, several violations of 
    safety standards contributed to the explosion or ignition, including 
    inadequate or entirely omitted examinations required by standards in 
    effect at the time. Compliance with those safety standards would have 
    significantly reduced the likelihood of these tragic accidents 
    occurring. Likewise, requirements of this final rule, such as the 
    requirements for preshift and supplemental examinations in areas where 
    persons are assigned to work or travel, would have served well to 
    prevent these accidents.
        The final rule requirements for on-shift examinations focus on the 
    areas most likely to develop hazards during a shift. Expanding the 
    examination requirements further is not supported by the record nor 
    needed for miner safety.
        As proposed, the final rule also revises paragraph (a)(1) to 
    clarify that sufficient on-shift examinations must be conducted to 
    assure safety. One commenter suggested that MSHA should include 
    language to require more than one examination if necessary for safety, 
    as provided for in the previous standard. The final rule adopts this 
    approach and requires that at least once during each shift, or more 
    often if necessary for safety, a certified person designated by the 
    operator must conduct an on-shift examination of each section where 
    anyone is assigned to work during the shift and any area where 
    mechanized mining equipment is being installed or removed during the 
    shift. As with other changes to this section, comments were received 
    both supporting and opposing the change. One commenter in opposition to 
    the standard argued that although the operator is required to maintain 
    a safe work environment at all times, documentation should not be 
    required for each inspection that is made of the working environment 
    throughout the shift. The commenter is correct in stating that the 
    rule, in Sec. 75.363, requires additional documentation. However, the 
    only additional documentation required will be for hazardous conditions 
    found during the additional on-shift examination conducted on non-coal 
    producing sections where miners are working. The additional 
    documentation required does not override the need for the standard. 
    Another commenter suggested that the term ``more often if necessary for 
    safety'' be changed to ``more often if necessary for safety as 
    determined by the operator depending on the mining conditions at the 
    time.'' This commenter stated that conducting additional checks for 
    safety is a current practice and individuals working on the section, 
    including the section foreman, are the most familiar with conditions in 
    that area and should make the determination whether additional 
    examinations are needed. MSHA agrees with this commenter that persons 
    working on a section are in the best position to identify the need for 
    additional examinations. The suggested language has not been adopted, 
    however, because MSHA believes that this determination should not be 
    limited to persons working on the section.
        Another commenter supported the proposal and listed explosions that 
    have occurred which, in the opinion of the commenter, could have been 
    prevented had additional on-shift examinations been made. MSHA agrees 
    that there are occasions when additional on-shift examinations are 
    necessary for safety and, therefore, the final rule requires that on-
    shift examinations be conducted at least once each shift, or more often 
    if needed for safety.
        The final rule retains the existing provision of paragraphs (a)(1), 
    (c)(1) and (c)(2) requiring an on-shift examination of areas where 
    mechanized mining equipment is being installed or removed. An in-depth 
    discussion of the reproposal of provisions concerning the installation 
    and removal of mechanized mining equipment is presented in the General 
    Discussion section of this preamble.
        Paragraph (a)(2) adds a new on-shift examination requirement to 
    address respirable dust control. Under the final rule, before coal 
    production begins on a section, an examination for compliance with the 
    dust control measures established in the mine ventilation plan must be 
    completed. This examination includes measurement of air quantities and 
    velocities, water pressures and flow rates, a check for excessive 
    leakage in the water delivery system, and checks of the number of 
    operating water sprays and their orientation as well as the placement 
    of section ventilation control devices.
        Assuring full compliance with these requirements is important in 
    safeguarding the health of miners. Human and financial costs 
    demonstrate the need for further attention. In 1990, approximately 2000 
    deaths were associated with Coal Worker's Pneumoconiosis and the total 
    number of deaths between 1968 and 1990 were over 55,000. As of 1993, 
    total annual Black Lung Program costs were over $1.3 billion and the 
    cumulative total cost had exceeded $30 billion.
        Agency experience shows that needed attention has not always been 
    given to the proper functioning of respirable dust controls. For 
    example, a series of special spot inspections, undertaken in 1991 to 
    conduct checks of the dust control parameters during the course of 
    working shifts, revealed that 21 percent of the 781 mining units 
    sampled were not complying with one or more of their dust control 
    parameters. In its 1992 report, an MSHA Task Group recommended coal 
    mine operators be required to make periodic on-shift examinations to 
    verify that the mine ventilation plan parameters are in place and 
    functioning as intended. MSHA considers on-shift examinations of 
    respirable dust controls an important part of reasonable and prudent 
    respirable dust control strategy.
        Several methods of measuring water spray pressures would be 
    acceptable. For example, water flow and pressure can be monitored 
    through the installation of an in-line water meter and a pressure 
    transducer. Water pressure can also be measured by permanently 
    installing a pressure gauge on a machine. Operators would determine the 
    working relationship between the pressure gauge reading and the actual 
    operating pressure at the sprays. Once the working relationship has 
    been established, the gauge pressure could be used to indicate the 
    actual spray pressure specified in the mine ventilation plan for a 
    given number and type of operating sprays.
        Measurement of any required water flow rate could be accomplished 
    through the installation of a flowmeter. A flowmeter provides a direct 
    and reliable measurement and is the preferred method of determining 
    water flow rate. Another acceptable method of determining flow rate 
    would be to establish the relationship between the water pressure and 
    the spray orifice diameter, either through engineering data or through 
    actual tests. Once established, the water pressure gauge reading could 
    be used to reliably indicate a flow rate for a specific number of 
    sprays at a given orifice size.
        One commenter, while generally supportive of the requirement for an 
    on-shift examination of respirable dust controls, expressed concern 
    over permitting the use of in-line flowmeters 
    
    [[Page 9799]]
    and pressure transducers. The commenter stated that leaks in the 
    location of the flowmeter and pressure transducer could go undetected, 
    resulting in a loss of pressure and flow at the sprays. MSHA agrees 
    that undetected leaks could result in improper operation of the system. 
    To address this point, the final rule has been revised from the 
    proposal to require that a check for excessive leakage in the water 
    delivery system be made during the on-shift. This commenter also 
    suggested that use of incorrect spray nozzles could result in improper 
    operation of the system that would not be detected with in-line 
    flowmeters and pressure transducers. MSHA would expect that as part of 
    the examination of the number of operating sprays a check would be made 
    to assure that the proper sprays are being used.
        The final rule requires that the number of water sprays and their 
    orientation be included in the examination. While spray orientation is 
    important in air-directing spray systems, such as sprayfans and 
    shearer-clearers, MSHA does not intend that precise angles be 
    determined during each examination. Rather, the examiner would be 
    responsible for assessing whether the direction and orientation of the 
    sprays are generally correct and in accordance with the requirements of 
    the mine ventilation plan.
        The final rule also requires that the working section ventilation 
    and control device placement be examined for compliance with the mine's 
    ventilation plan. Mine ventilation, particularly where coal extraction 
    occurs, is a basic respirable dust control measure.
        Any other respirable dust controls specified in the approved mine 
    ventilation plan are also included in the scope of the examination 
    required under the final rule. An example of such controls is the 
    cleaning and maintenance procedures for a wet bed scrubber installed on 
    a continuous mining machine. The examination would include a check to 
    assure that air inlets and discharges are not plugged. It is not MSHA's 
    intent that the air quantity produced by a machine-mounted scrubber be 
    measured as part of the on-shift examination required by paragraph 
    (a)(2), unless such a requirement is included as a part of the mine 
    ventilation plan.
        MSHA is aware that through advances in technology it may be 
    feasible to continuously monitor air quantity and velocity, and spray 
    water flow rate and pressure. Continuous monitoring offers the 
    potential to further improve miner protection by providing real-time 
    data on the performance and condition of key dust control measures. 
    This information can be used to give early warnings of deteriorating 
    dust controls, allowing corrective action to be taken before the dust 
    control system fails to protect miners from excessive dust levels. 
    Although continuous monitoring will eliminate the need for periodic 
    physical measurements to verify proper operation of some dust controls, 
    visual observation of other controls will still be necessary. Among 
    these are the number and location of operating water sprays, their 
    general condition and orientation, the section ventilation setup and 
    control device placement, the check for excessive leakage in the water 
    delivery system, and other control measures where performance and 
    operating condition can only be assessed visually.
        One commenter suggested that MSHA not permit the use of continuous 
    monitoring in lieu of physical checks because technology to permit such 
    monitoring is not as yet available. The final rule is intended to be 
    sufficiently flexible to permit the use of new technology, such as 
    continuous monitoring and sensing devices, and also to encourage the 
    introduction of such modern equipment. The final rule does not require 
    the physical measurement of the air velocity and quantity, water 
    pressure and flow rates if continuous monitoring of the dust control 
    parameters is used and indicates that the dust controls are functioning 
    properly.
        The on-shift examination of the dust controls is to be completed 
    under the direction of a person who has been designated by the 
    operator. The proposal would have required that a certified person 
    conduct the examination. One commenter objected to this approach, 
    suggesting that the completion of this examination would require 
    considerable time and that a more thorough examination could be 
    accomplished by a person(s) familiar with the equipment and the dust 
    control measures being utilized. This commenter recommended that MSHA 
    remove the word ``certified'', thus permitting the examination to be 
    conducted by persons other than certified persons. A second commenter 
    argued that the examination should be conducted by a single individual 
    because other persons may be assigned to a section who are not familiar 
    with the requirements of the mine ventilation plan for that section.
        The final rule deletes the word ``certified,'' permitting on-shift 
    examinations of dust controls to be conducted by one or more persons 
    who are not certified individuals. However, the examination must still 
    be conducted under the direction of a person designated by the operator 
    and as set out in paragraph (g)(2), a certified person must certify 
    that the examination has been completed. MSHA would expect that the 
    person directing this examination would be present at the site of the 
    examination while the examination is conducted.
        Another commenter recommended that the final rule not specify the 
    measurements that are to be made need during the on-shift examination 
    of dust controls, and that the standard be rewritten to require such an 
    examination be sufficient to assure compliance with the respirable dust 
    parameters specified in the mine ventilation plan. Because it is 
    possible to identify specifically some of the parameters that must be 
    measured in all instances the suggestion of the commenter has not been 
    adopted. By identifying these parameters in the final rule, 
    misunderstandings over whether a plan specification is for dust control 
    or methane control, for example, can be eliminated.
        As proposed, paragraph (a)(2) would have required that the 
    respirable dust control portion of the examination be made at or near 
    the beginning of the shift and before production begins on a section. 
    One commenter suggested that such a requirement would eliminate the 
    common practice of changing shifts on the section without an 
    interruption in production. MSHA recognizes that changing crews without 
    an interruption in production has become a common practice in some 
    areas and does not intend that this practice be changed by this rule. 
    The final rule has revised the proposal so that when a shift change is 
    accomplished without an interruption in production on a section, the 
    required examination may be made any time within 1 hour of the shift 
    change. In those instances when there is an interruption in production 
    during a shift change, the final rule requires that the on-shift 
    examination of respirable dust controls be made before production 
    begins on a section. The proposed wording ``at or near the beginning of 
    the shift'' has not been included in the final rule in recognition of 
    the fact that production on a section could be delayed and not begun 
    until well after the beginning of the shift. Because the purpose of the 
    standard is to assure that dust exposures are controlled during mining, 
    the on-shift examination must be conducted prior to the beginning of 
    production in order to be most effective.
        Other commenters objected to examining respirable dust control 
    parameters for various reasons. Some commenters stated that operators 
    are 
    
    [[Page 9800]]
    required to comply with the requirements of the mine ventilation plan 
    relative to dust control and a separate requirement is not needed. The 
    measurements specified in the final rule are a practical way to provide 
    reasonable assurance that miners are not being exposed to unhealthy 
    levels of respirable dust. The purpose of these checks is not to 
    restate the requirements for compliance with the mine's ventilation 
    plan. Instead, as discussed above, the final rule is intended to bring 
    needed attention to the proper functioning of dust controls before 
    production begins.
        Other commenters expressed the opinion that coal production should 
    not be delayed until after the completion of the examination of dust 
    controls. According to these commenters, this examination will take the 
    certified person away from other examinations that must be completed to 
    assure safety. As explained previously, the final rule has been revised 
    to permit the changing of crews without an interruption in production. 
    The completion of the on-shift examination of dust control parameters 
    can be postponed for up to 1 hour when crews are switched out at the 
    face. Additionally, the final rule has been revised to permit the 
    examination of dust control parameters to be performed by a person(s) 
    other than a certified person and to simply require the certified 
    person to certify that the examination was completed. These revisions 
    substantially reduce any delay in production that could have resulted 
    under the rule as proposed.
        Another commenter objected to the requirements of paragraph (a)(2) 
    stating that examination of dust controls is unnecessary because all 
    personnel are required to be trained in the requirements of all 
    approved mine plans including the mine ventilation plan, and many of 
    the required mine ventilation plan parameters are checked during the 
    pre-shift examination. The commenter stated further that other 
    parameters, such as number of water sprays and pressure, are checked by 
    the equipment operators during the pre-operational inspection. In the 
    opinion of the commenter, the proposed examination of dust control 
    parameters is redundant and unnecessary.
        The requirements of paragraph (a)(2) are not redundant with 
    existing standards. There is no requirement for a pre-operational 
    inspection of dust controls. For the reasons discussed above, MSHA 
    considers examination of dust controls for proper functioning to be an 
    important practical measure for protecting miners'' health. To the 
    extent that these checks are currently being made by some operators, 
    together with the flexibility of the final rule, the burden of making 
    these checks is minimized.
        The final rule requires in paragraph (a)(2) that deficiencies found 
    during the on-shift examination of dust controls be corrected before 
    production begins, or when crews are changed without an interruption in 
    production, before production continues. The proposal would have 
    required that deficiencies in the controls be corrected immediately. 
    However, the final rule revises the proposal in response to one 
    commenter who pointed out that the correction of deficiencies is 
    important prior to production, in view of the purpose of the rule.
        Another commenter suggested that the examination of dust controls 
    be conducted after production begins so as to be more representative of 
    production conditions. In contrast, another commenter observed that if 
    the required dust control parameters are not being met before 
    production is begun, it is unlikely that they will be met after 
    production is started. This commenter suggested multiple examinations, 
    one before production begins and one at some later time during the 
    shift. MSHA agrees that if dust control measures are deficient before 
    production begins it is unlikely that they will be corrected later in 
    the shift. Therefore the final rule requires the on-shift examination 
    of the dust control measures prior to the beginning of production. The 
    final rule, however, does not include the recommendation for an 
    additional examination of dust control measures.
        Paragraphs (c)(1) and (c)(2) require certified persons conducting 
    on-shift examinations to take air measurements at the same locations 
    where air measurements are required during the preshift examination. 
    This includes areas where mechanized mining equipment, including 
    longwall or shortwall mining equipment, is being installed or removed. 
    Reduced volume or velocity of air during the shift can contribute to 
    increased levels of respirable dust, methane accumulations, or oxygen-
    deficient atmospheres. Checking the mine's ventilation system verifies 
    that changes in the mine ventilation system due to the production 
    process have not occurred.
        The final rule removes the word ``working'' from paragraph (c)(1) 
    to assure that the application of the standard would extend to all 
    sections, consistent with paragraph (a). Many of the activities to 
    which miners are assigned are on sections not normally thought of as 
    ``working sections,'' a term associated with coal production. For 
    purposes of Sec. 75.362, a section in the mine is considered to be the 
    area inby the loading point; or, in the case of the installation of 
    mechanized mining equipment, inby the proposed loading point; or, in 
    the case of the removal of mechanized mining equipment, inby the 
    location of the last established loading point. The final rule requires 
    in paragraphs (a)(1), (c)(1), and (c)(2) that the certified person 
    conducting the on-shift examination examine the section in much the 
    same way as it would be examined during a coal producing shift, 
    including checking for hazardous conditions, testing for methane and 
    oxygen deficiency, determining if the air is moving in its proper 
    direction, and measuring the volume of air in the last open crosscut or 
    in the intake of longwalls or shortwalls, as appropriate.
        Some commenters objected to this provision stating that there is 
    little safety benefit to requiring on-shift examinations on sections 
    other than working sections where coal is being produced. The final 
    rule does not limit on-shift examinations to ``working sections'' but 
    includes other areas where persons are working. Hazards similar to 
    those that develop on a coal producing section can also develop during 
    a shift on sections that are not producing, but where personnel are 
    assigned to work.
        Paragraph (d)(1)(i) requires that at the start of each shift, 
    before electrically operated equipment is energized, a qualified person 
    test for methane at each working place. One commenter suggested that 
    the existing standard is sufficient because quite often in today's 
    mining practices equipment is already energized at the start of the 
    shift since one equipment operator takes over from the previous 
    operator and examinations for methane have been performed every 20 
    minutes as required by Sec. 75.362(d)(1)(ii). MSHA does not agree that 
    the existing standard is sufficient for a number of reasons. First, 
    although the commenter is correct in stating that switching operators 
    while the equipment remains energized is a relatively common practice 
    it is not a universal practice. In mines where equipment is deenergized 
    between shifts, the final rule provides for a test for methane in each 
    working place prior to the equipment being energized. On sections in 
    mines where equipment operators are switched while equipment remains 
    energized, MSHA would consider a methane test performed during the 
    previous 20 minutes under paragraph (d)(1)(iii) as sufficient to comply 
    with the methane test requirement of paragraph (d)(1)(i) for the 
    working place where mining is taking place. However, paragraph 
    
    [[Page 9801]]
    (d)(1)(i) also requires that methane tests be made in other working 
    places on the section not only in the working place where the equipment 
    is being operated.
        The final rule requires in paragraph (d)(1)(iii) that methane tests 
    be made more frequently than 20 minutes if required in the approved 
    mine ventilation plan at specific locations, during the operation of 
    equipment in the working place. One commenter objected to this 
    requirement expressing the opinion that the standard does not identify 
    situations in which more frequent methane tests would be warranted and, 
    therefore, operators could be faced with a requirement to conduct 
    additional methane tests which are unwarranted and would result in the 
    misallocation of safety resources. The final rule is intended to 
    address situations such as an abnormally high methane liberation rate 
    in a mine or an area of a mine that would warrant more frequent testing 
    for methane. Like the existing standard the final rule requires this 
    test to be made by a qualified person, not a certified person, thus in 
    most cases the person who makes the test will be the machine operator. 
    As a result, this test will not require that other safety-related 
    activities be stopped to make a test for methane.
        Under the existing rule, methane tests required by paragraph (d)(1) 
    were to be made at the last permanent roof support unless the mine 
    ventilation plan required that they be made closer to the face using 
    extendable probes. Paragraph (d)(2) of the final rule revises this 
    standard and requires that the methane tests specified in paragraphs 
    (d)(1)(i) through (d)(1)(iii) be made at the face from under permanent 
    roof support, using extendable probes or other means. Like the existing 
    standard, paragraph (d)(2) requires that for longwall and shortwall 
    mining systems, the tests are to be made at the cutting head. When 
    mining has been stopped for more than 20 minutes, methane tests must be 
    made prior to the start up of the equipment.
        During informational meetings following the publishing of the 
    existing standard, it became apparent that a large segment of the 
    mining community felt that methane tests should be made as close to the 
    working face as practicable without exposing miners to unsafe 
    conditions. MSHA agrees that proper testing for methane at the face is 
    essential for safe mining operations. The need for making methane tests 
    at the face has been demonstrated by researchers and engineers from the 
    U.S. Bureau of Mines and MSHA through work performed over the last 25 
    years. This work documents that in a working place the concentrations 
    near the face are considerably higher than other areas in the working 
    place. For example, Luxner, in Bureau of Mines Report of Investigation 
    7223, ``Face Ventilation in Underground Bituminous Coal Mines,'' 
    published in 1969, reported methane concentration in excess of 5 
    percent as far back as 15 feet using both blowing and exhaust 
    ventilation systems with a curtain-to-face distance of 20 feet. The 
    concentration outby this location as reported by Luxner was between 
    zero and 1 percent. Later, Haney, et al., also showed lesser 
    concentrations of methane further from the face using various types of 
    assisted ventilation systems.
        A speaker at one of the public hearings on the proposal suggested 
    that tests should be made at the last row of bolts and if 0.2 percent 
    of methane is found at that location, a probe should be used to test at 
    the face. The final rule does not adopt this recommendation because 
    MSHA is unaware of any tests that relate the concentration of methane 
    at the face with the concentration at the last row of bolts. Based on 
    current knowledge, it is doubtful that such a direct correlation could 
    be made because of the number of variables involved.
        A recurring comment concerning taking methane tests at the face 
    with a probe was that such a requirement will lead to an increase in 
    the number of back injuries among miners. However, other commenters 
    supported the requirement and stated that probes as long as 40 feet are 
    currently being used in some areas of the country. Miners with 
    experience in using these probes testified at the rulemaking hearings 
    that although the long probes can at times be difficult to use, they 
    are being used and are providing measurements of methane at the face in 
    mines operating in coal seams as low as 37 inches.
        The possibility of an increase in the number of back injuries is of 
    serious concern to MSHA. However, after reviewing all of the written 
    comments and testimony taken during public hearings, particularly that 
    of miners having experience with the use of probes, MSHA is persuaded 
    that this is a reasonable approach and will achieve the desired safety 
    results without undue risk of back injuries.
        Several commenters suggested that in lieu of requiring methane 
    tests at the face, MSHA should permit the use of the methane monitor to 
    satisfy the requirement. In making this recommendation, one commenter 
    suggested that the methane monitors should not be required to be 
    installed on face equipment if they cannot also be used to test for 
    methane in unsupported faces. Methane monitors have proven reliable 
    over the years and provide a second level of protection against methane 
    ignitions. Methane monitors provide for methane detection at a fixed 
    location while the use of a methane detector with a probe permits 
    methane measurements to be made at various locations in the face area.
        Historically, machine-mounted methane monitors have been used as a 
    backup for the other required tests. This concept was exactly what 
    Congress recognized in Sec. 303(l) of the Coal Mine Health and Safety 
    Act of 1969 (Coal Act). Discussing this provision, the conference 
    managers noted ``...the methane monitor is an additional backup device 
    for detecting methane and should not be construed as a substitute for 
    the other tests and testing devices required in this title for 
    detecting and controlling methane.'' H.R. Conf. Rep. No. 91-761, 91st 
    Cong., 1st Sess. 80 (1969).
        The final rule does not adopt the suggestion of commenters that 
    methane monitors be accepted in lieu of the methane tests required by 
    paragraph (d)(2).
        Paragraph (g)(1) adopts the language of proposed paragraph (g) and 
    requires that the person making the on-shift examination in belt 
    haulage entries certify by initials, date, and time that the 
    examination was made at enough locations to show that the entire area 
    has been examined. As explained in the preamble to the proposal, the 
    existing rule does not require certification that examinations were 
    conducted in belt conveyor entries. Comments received expressed the 
    view that without certification, no mechanism exists to verify that 
    examinations were conducted in belt conveyor entries. Other commenters 
    questioned what MSHA meant by ``enough locations.'' MSHA agrees with 
    the commenter that the certification requirement should be added to the 
    rule to provide a means to verify that the examination has taken place. 
    With respect to the locations where the certification should be made, 
    this certification process is a common practice in the industry and is 
    required by several state regulations. The locations where 
    certification would be expected to be kept are no different than those 
    which were required for many years under the previous MSHA regulation 
    and which have been commonly accepted in the industry. Paragraph (g)(2) 
    is a new requirement relating to the certification of the examination 
    of respirable dust control parameters. Under (g)(2), the person making 
    the on-shift examination to assure compliance with the respirable 
    
    [[Page 9802]]
    dust control parameters specified in the mine ventilation plan must 
    certify by initials, date, and time that the examination was made.
    
    Section 75.363  Hazardous Conditions; Posting, Correcting, and 
    Recording
    
        Section 75.363 is a new section requiring the posting, correcting 
    and recording of hazardous conditions. The posting of hazardous 
    conditions against entry is a time tested method for preventing 
    accidents. Examiners, upon finding a hazardous condition, erect 
    ``danger boards'' to alert persons traveling in the area of the 
    presence of the hazard. In this manner, miners are prevented from 
    inadvertently entering an area where a hazard exists. Section 75.363 
    requires that hazardous conditions be posted and access to the area be 
    limited; that the hazardous conditions be corrected immediately or 
    remain posted; and, that a record be made and maintained of the 
    hazardous condition and the action taken to correct the condition. 
    Records of the hazards and the actions required to correct the hazards 
    provide valuable safety information about conditions in the mine and 
    the effectiveness of corrective measures.
        MSHA's final rule modifies the proposal in several ways. The final 
    rule deletes the phrase ``or reported to'' that appeared in the first 
    sentence of proposed Sec. 75.363(a) and deletes the requirement for 
    countersigning by a second level official. It specifies that, except 
    for preshift or preshift type examinations, hazardous conditions shall 
    be corrected immediately or posted until the conditions are corrected. 
    The final rule allows for countersigning by an official equivalent to 
    the mine foreman and provides for storage of records in either a secure 
    book or in electronic media which is not susceptible to alteration.
        It is essential that all hazardous conditions, regardless of when 
    detected or by whom, be adequately addressed. Commenters suggested that 
    the proposed standard be deleted because, in their opinion, other 
    standards provide adequate coverage. One commenter interpreted the 
    proposed standard as being directed at only those hazards found during 
    the on-shift examination and supplemental examinations, because 
    hazardous conditions found during the preshift and weekly are excluded 
    from the standard. This commenter recommended rewriting the 
    requirements for the on-shift and supplemental examinations to reflect 
    the needed changes.
        Section 75.363 is not directed only toward hazardous conditions 
    found during examinations. Hazardous conditions occur and are found at 
    times during the shift when examinations are not being made. Under the 
    final rule, these hazardous conditions would also require posting, 
    correction, and recording when found by the mine foreman or equivalent 
    mine official, assistants to the mine foreman or equivalent mine 
    official, or other certified persons designated by the operator to 
    conduct examinations.
        One commenter questioned whether the proposed standard was intended 
    to assign new duties to the mine foreman and assistant mine foremen. 
    The final rule does not impose additional responsibilities on the mine 
    foreman and assistant mine foremen. However, these individuals are 
    certified and routinely travel throughout the mine for purposes other 
    than making examinations. The standard requires that hazardous 
    conditions found by the mine foreman, assistant mine foreman, or 
    equivalent mine officials, be treated the same as hazardous conditions 
    found by other certified persons who have been designated to conduct 
    examinations. That is, the hazardous conditions are to be appropriately 
    posted, corrected, and recorded. The term ``equivalent mine officials'' 
    has been added in response to commenters who suggested that the term 
    ``mine foreman'' is no longer used at all mines.
        Under paragraph (a) any hazardous condition found by the mine 
    foreman or equivalent mine official, assistants to the mine foreman or 
    equivalent mine official, or other certified persons designated by the 
    operator to conduct examinations is to be posted with a conspicuous 
    danger sign. The posting requirements of this section apply to every 
    hazardous condition regardless of when it is found. Under the proposal, 
    hazardous conditions reported to the mine foreman, assistants to the 
    mine foreman or other certified persons designated by the operator to 
    conduct examinations would have required posting. Commenters suggested 
    that requiring hazardous conditions ``reported to'' these individuals 
    would eliminate the judgement of the persons responsible for making 
    decisions about whether or not a hazardous condition exists. One 
    commenter suggested that the requirement, as proposed, could undermine 
    the integrity of the certified person. The final rule is revised to 
    require that hazardous conditions found by the mine foreman or 
    equivalent mine official, assistant mine foreman or equivalent mine 
    official, or other certified persons designated by the operator for the 
    purpose of conducting examinations shall be posted with a conspicuous 
    danger sign and shall be corrected immediately or remain posted. MSHA 
    would expect that when a hazardous condition is reported to these 
    certified persons, that the measures necessary to evaluate the 
    situation and, if necessary, to comply with the provisions of this 
    section would be taken.
        One commenter suggested that the proposed requirement that all 
    hazardous conditions be corrected ``immediately'' would diminish safety 
    because miners could be exposed to hazards unnecessarily. The commenter 
    offered as an example an area of bad roof in a ``remote, unused 
    crosscut'' and suggested that in this case posting of the area against 
    entry would be sufficient. MSHA recognizes that there are instances, 
    such as the example presented by the commenter, where safety is best 
    served by simply posting the area against entry. This has long been the 
    practice in the industry and the final rule does not prevent this from 
    continuing. In these cases, the corrective action required to prevent 
    injury is to preclude persons from entering the area. The proposal 
    would have required that the hazardous condition be corrected 
    immediately and that the area remain posted until the hazardous 
    condition is corrected. To reflect the recommendation of the commenter, 
    the final rule requires that the hazardous condition be corrected 
    immediately or that the area remain posted until the hazardous 
    condition is corrected. The Agency recognizes that in some instances 
    posting the area against entry is the corrective action.
        The requirement that the hazardous conditions be corrected 
    immediately does not necessarily require correction by the certified 
    examiner finding the condition. To do so could delay the completion of 
    the examination. Rather, the final rule requires that the hazardous 
    condition be corrected following the reporting of the condition by the 
    examiner to the appropriate mine official. Common sense and sound 
    judgement should enter into the decisions as to when hazardous 
    conditions are corrected. Posting of the area where the hazardous 
    condition exists in order to prevent entry is to be accomplished by the 
    certified person finding the hazardous condition.
        One commenter questioned whether proposed paragraph (a) would 
    require the hazardous condition itself be posted. The posting of the 
    area, as opposed to the hazardous condition itself, would, in most 
    cases, be more effective and a safer practice. For instance, if a 
    section 
    
    [[Page 9803]]
    of bad roof is detected, it would be in the best interest of safety to 
    mark the area or perimeter of the area of bad roof instead of the roof 
    itself. The ``danger'' sign would be placed at a location where anyone 
    entering the area of the hazardous condition would pass so that persons 
    approaching the area would be expected to see the ``danger'' sign. The 
    area would remain posted until the hazardous conditions are corrected. 
    The posting of areas where hazardous conditions exist to alert persons 
    is a long-standing accepted safety practice in the mining community.
        Paragraph (a) requires that once an area is posted due to a 
    hazardous condition, only persons designated by the operator to correct 
    or evaluate the condition may enter the posted area. Additionally, if 
    the hazardous condition creates an imminent danger, everyone must be 
    withdrawn from the affected area to a safe area until the condition is 
    corrected. Persons referred to in section 104(c) of the Act are 
    permitted to enter in the area.
        One commenter suggested that the representative of the miners be 
    permitted to enter an area which has been posted with a ``danger'' in 
    order to evaluate the condition. The final rule follows the statutory 
    provision in Sec. 104(c) of the Mine Act. This longstanding requirement 
    provides that only persons designated by the operator to correct or 
    evaluate the hazardous condition may enter such posted areas. With 
    respect to the representative of miners, Sec. 104(c)(3) provides that 
    the representative of the miners in such mine who is, in the judgment 
    of the operator or an authorized representative of the Secretary, 
    qualified to make mine examinations or who is accompanied by such a 
    person and whose presence in such area is necessary for the 
    investigation of the hazardous condition may enter the area.
        Paragraph (b) requires that a record of hazardous conditions be 
    made by the end of the shift on which the condition was found. This 
    record is required to be maintained on the surface and must include the 
    nature and location of the hazardous condition and the corrective 
    action taken. A record of all hazards found, as well as the required 
    corrective action, serves as a history of the types of conditions that 
    can be expected in the mine. When the records are properly completed 
    and reviewed, mine management can use them to determine if the same 
    hazardous conditions are recurring and if the corrective action being 
    taken is effective. No record is required on any shift on which no 
    hazardous conditions are found. Paragraph (b) excludes hazardous 
    conditions found during the preshift and weekly examinations because 
    these examinations have separate record keeping requirements.
        Commenters recommended rewording the standard to eliminate the 
    provisions that no record is required on any shift on which no 
    hazardous condition is found and that the corrective action taken must 
    also be recorded. These suggestions were offered to clarify the 
    standard. MSHA believes that deleting these requirements would not 
    clarify the rule and the suggestions are not adopted in the final rule.
        Paragraph (c) requires that a record be made either by the 
    certified person who conducted the examination or by a person 
    designated by the operator. As with other records required by this 
    subpart, when the record is made by a designated person other than the 
    certified person making the examination, the person making the record 
    need not be certified. If the record is made by a person designated by 
    the operator, the certified person must verify the record by initials 
    and date. MSHA did not receive any comments objecting to this part of 
    the standard. Like the other recordkeeping requirements in the 
    proposal, proposed paragraph (c) would have required that the record be 
    made in a state-approved book or a bound book with sequential machine-
    numbered pages. Additionally, the proposal would have required 
    countersigning by both the mine foreman and the superintendent or 
    equivalent individual to whom the mine foreman reports. The final rule 
    requires that the records of hazardous conditions must be kept in 
    either secure books that are not susceptible to alteration, or 
    electronically in a computer system so as to be secure and not 
    susceptible to alteration. A detailed discussion of record books and 
    the use of computers to maintain records can be found in the General 
    Discussion of this preamble.
        A variety of comments were received regarding the countersigning of 
    the record by the mine foreman, and the time permitted for 
    countersigning. The final rule adopts the proposal that the mine 
    foreman or equivalent mine official must countersign the record of 
    hazardous conditions by the end of the mine foreman's next regularly 
    scheduled working shift. The mine foreman is responsible for the day-
    to-day operation of the mine. It is essential for the health and safety 
    of the miners that the mine foreman be fully aware of the information 
    contained in this record so as to be able to allocate resources to 
    correct safety problems as they develop. Allowing until the end of the 
    mine foreman's next regularly scheduled working shift to countersign 
    the records assures that the mine foreman is aware of hazardous 
    conditions in sufficient time to initiate corrective actions.
        Some commenters suggested that the time for countersigning is 
    unnecessarily long, and that the final rule should require daily 
    countersigning by the mine foreman. The rulemaking record does not 
    show, however, that the time set by the final rule would expose miners 
    to safety or health risks. Also, hazardous conditions must be corrected 
    immediately or the area must remain posted until the condition is 
    corrected.
        Numerous comments were received regarding the requirement of the 
    proposal for second level countersigning of the preshift examination 
    record by the mine superintendent, mine manager, or other mine official 
    to whom the mine foreman is directly accountable within 2 scheduled 
    production days after the countersigning by the mine foreman. The final 
    rule does not retain this proposed requirement. A detailed discussion 
    of the subject of second level countersigning can be found in the 
    General Discussion section of this preamble.
        As proposed, paragraph (d) of the final rule requires that the 
    records required by Sec. 75.363 be maintained at a surface location at 
    the mine for one year and be made available for inspection by 
    authorized representatives of the Secretary and the representative of 
    miners. Comments on this requirement were generally favorable. A 
    discussion of comments concerning the use of computers to maintain 
    records can be found in the General Discussion of this preamble.
    
    Section 75.364  Weekly Examination
    
        The weekly examination is directed at hazards that develop in the 
    more remote and less frequently visited areas of a mine. These areas 
    include: worked-out areas where pillars have not been removed, bleeder 
    entries used to ventilate worked-out areas where pillars have been 
    removed and, some main intake and return air courses. Over the course 
    of time, hazards such as methane accumulations and obstructions to 
    ventilation can develop in these areas and can result in an explosion 
    or loss of ventilation if not discovered and corrected. Because of the 
    confined nature of the underground mining environment, loss of life can 
    result in other areas of the mine outside the immediate location of the 
    hazard. The weekly examination assures that these hazards are located 
    and corrected.
        Generally, Sec. 75.364 requires an examination in unsealed worked-
    out areas that have not been pillared; travel 
    
    [[Page 9804]]
    in bleeder entries and the performance of appropriate measurements in 
    these entries and; a check for hazardous conditions in return and 
    intake air courses, in each longwall travelway, at each seal along 
    return and bleeder air courses and each seal along intake air courses 
    not otherwise examined, in each escapeway, and each working section 
    that has not been preshift examined during the previous 7 days.
        The final rule modifies existing Sec. 75.364 (a), (b), and (h). It 
    adopts several proposed changes to Sec. 75.364 and modifies or rejects 
    other proposed changes.
        Paragraph (a) specifies weekly examination requirements in unsealed 
    worked-out areas where no pillars have been recovered as well as in 
    bleeder systems. The final rule requires that unpillared worked-out 
    areas and bleeder systems be physically examined on a weekly basis and 
    specifies the tests and measurements to be performed by the examiner. 
    The final rule identifies two separate locations within nonpillared 
    areas and bleeder systems where measurements may be required. First, 
    measurement points must be included in the mine ventilation plan to 
    identify the locations within unpillared worked-out areas and bleeder 
    systems where examiners will conduct air measurements and tests, the 
    results of which are to be recorded. These measurement points are not 
    in lieu of traveling the system, but rather are the locations where the 
    examiner will perform air quantity and quality tests and measurements 
    to determine the effectiveness of ventilation. These points are 
    tracking and evaluation tools to assure adequate ventilation and to 
    identify developing trends in ventilation or air quality which may 
    require attention.
        Second, evaluation points may be approved in the mine ventilation 
    plan on a case-by-case basis as provided under (a)(1) and by 
    (a)(2)(iv). These evaluation points may be used in lieu of physical 
    examinations. Evaluation points may only be approved in lieu of travel 
    if the evaluation points are fully adequate to demonstrate that the 
    area is ventilated. These provisions are discussed below.
        The final rule clarifies that measurement points for weekly 
    examinations must be specified in the mine ventilation plan for both 
    unpillared and pillared worked-out areas described in (a)(1) and 
    (a)(2)(iii), respectively. These measurement points are distinct from 
    the evaluation points which may be approved in lieu of a physical 
    examination under some circumstances. As mentioned above, evaluation 
    points are governed by (a)(1) for unpillared worked-out areas, and by 
    (a)(2)(iv) for pillared worked-out areas ventilated by bleeder systems. 
    Section 75.371(z) of the final rule refers to these requirements for 
    both measurement points and evaluation points. The measurement points 
    and evaluation points may be either in the body of the mine ventilation 
    plan or may be shown on the 75.372 map. In either case, the locations 
    are subject to approval by MSHA.
        Under paragraph (a)(1), at least every 7 days a certified person 
    must examine unsealed worked-out areas where no pillars have been 
    recovered by traveling to the area of deepest penetration; measuring 
    methane and oxygen concentrations and air quantities and making tests 
    to determine if the air is moving in its proper direction in the areas. 
    The locations of measurement points where tests and measurements will 
    be performed must be included in the mine ventilation plan and must be 
    adequate in number and location to assure ventilation and air quality 
    in the area. Air quantity measurements must be made where the air 
    enters and leaves the worked-out areas. Sufficient methane and oxygen 
    measurements must be made to assure the air quality in the worked-out 
    areas. An alternative method of evaluating the ventilation of the areas 
    may be approved in the mine ventilation plan.
        Under paragraph (a)(1), in addition to measuring oxygen and methane 
    concentrations and testing for proper air direction, air quantities 
    must also be determined. Air quantity measurements are required where 
    air enters and leaves the worked-out area. The final rule also requires 
    that a sufficient number of measurement points must be included in the 
    mine ventilation plan to assure appropriate ventilation and air quality 
    in the area.
        The changes to paragraph (a)(1) are in response to comments and 
    MSHA experience with weekly examinations. Currently some examiners are 
    simply traveling to the point of deepest penetration while conducting 
    few if any tests or air measurements within the system. The full 
    benefit of an examiner traveling to the point of deepest penetration is 
    lost if the examiner does not conduct air quantity and quality 
    measurements at key locations.
        The results of these measurements are important in assessing the 
    effectiveness of ventilation. In addition, trends in either air 
    quantity or quality can reveal developing problems which can be 
    corrected in the earliest stages.
        One commenter suggested that the entire perimeter of worked-out 
    areas should be physically examined to all points of deepest 
    penetration. The commenter suggested that the face of each entry or 
    room should be examined at its point of deepest penetration. MSHA 
    agrees that travel to a single point of deepest penetration within an 
    area may sometimes be inadequate to fully demonstrate effective 
    ventilation of a worked-out area. The final rule addresses this issue 
    by requiring that measurement points be established in the mine 
    ventilation plan.
        Paragraphs (a)(2) (i) through (iv) of the final rule retain the 
    requirement that at least every 7 days a certified person must evaluate 
    the effectiveness of bleeder systems used under Sec. 75.334 (b) and 
    (c). Like the proposal, the final rule also specifies tests and 
    locations for an effective examination. One commenter noted that mine 
    examinations are sometimes ineffective and supported the proposed 
    additional specificity in the rule, requiring air measurements and 
    tests at key locations or measurement points within worked-out areas. 
    Established locations where examiners will conduct air measurement and 
    tests will help assure effective examinations and provide quantitative 
    results to the operator. The final rule requires that the mine 
    ventilation plan include measurement points within worked-out areas and 
    paragraph (h) requires that the results be recorded.
        Paragraph (a)(2)(ii) requires that measurements of methane and 
    oxygen concentrations be made, air quantity be measured, and a test 
    performed to determine if the air is moving in its proper direction at 
    a point immediately before the air enters a return split of air. A 
    commenter supported the proposed air measurements where air enters and 
    leaves worked-out areas and correctly noted that such measurements 
    would reveal some types of ventilation problems. In a special case, 
    such as where it may not be possible to measure intake air, paragraph 
    (a)(2)(iv) permits an alternate method of evaluation to be used when 
    approved in the mine's ventilation plan.
        Another potential hazard exists when multiple intake openings lead 
    into such an area, if passing intake air enters upstream openings of 
    the worked-out area and reenters the intake from downstream openings. 
    The final rule also requires that air quantity measurements be made 
    where air enters and leaves worked-out areas. Measurements made where 
    air enters and exits the area will alert the examiner and operator to 
    airflow changes or imbalances which indicate a potentially dangerous 
    ventilation problem. The specification of 
    
    [[Page 9805]]
    measurement points within worked-out areas will also assure that short 
    circuits have not interrupted ventilation.
        One commenter stated that the standard should fully delineate all 
    aspects of the weekly examination by specifying that the examination 
    include roof and ribs, ventilation controls, water accumulations, etc. 
    Although MSHA agrees that these and other conditions fall within the 
    purview of the weekly examination, the final rule does not attempt to 
    provide an exhaustive list of what is to be covered in a weekly 
    examination. Examinations are performed by persons trained and 
    certified as able to make the required examinations. Such certified 
    persons can be expected to give proper attention to basic safety 
    considerations.
        Paragraph (a)(2)(iii) requires that at least one entry of each set 
    of bleeder entries used as part of a bleeder system under Sec. 75.334 
    must be traveled in its entirety. Under the final rule, measurements of 
    methane and oxygen concentrations and air quantities are required to be 
    made during the examination. Also, a test to determine if the air is 
    moving in its proper direction must be made at locations or measurement 
    points, specified in the mine's ventilation plan. The measurements and 
    tests provide the information necessary to determine the effectiveness 
    of the bleeder system.
        One commenter believed that the proposal would require each 
    parallel and common bleeder entry of a set to be traveled. The final 
    rule is intended to simplify the examination and would, under the 
    circumstances described by the commenter, require only one entry of a 
    set of common entries to be examined in a bleeder system. Also, similar 
    to the requirements for traveling intake and return air courses, this 
    requirement should not be interpreted to require the examiner to stay 
    in one entry. For example, if the examiner desires to ``zig zag'' 
    between entries while traveling in a multi-entry bleeder system, this 
    would be acceptable under the regulation provided tests and 
    measurements are made at the appropriate locations.
        Paragraph (a)(2)(iv) provides that, in lieu of the requirements of 
    (i) through (iii), alternative methods of evaluation may be specified 
    in the mine ventilation plan provided that the alternative method 
    results in proper evaluation of the effectiveness of the bleeder 
    system. One commenter cited several explosions that were related to 
    bleeder system deficiencies and linked poor design and inadequate 
    maintenance with the provision allowing examination at evaluation 
    points in lieu of traveling the area in its entirety. The thrust of the 
    commenter's argument was that an inflexible standard requiring either 
    full travel of a bleeder system or sealing of the entire area would 
    result in superior designs and improved maintenance. While MSHA agrees 
    with the commenter's ultimate objective of ensuring effective 
    ventilation of bleeder systems and worked-out areas, MSHA does not 
    agree that elimination of any flexibility within the standard would 
    result in infallible designs. Since approval of evaluation points is 
    only granted in cases where adequate ventilation can be determined 
    through evaluation, MSHA believes that retaining flexibility to review 
    individual cases is an appropriate method and results in proper 
    evaluation of the effectiveness of the bleeder system.
        Paragraph (h) of the final rule governs recordkeeping requirements 
    for weekly examinations. The final rule incorporates several revisions 
    based on recommendations submitted by commenters. The final rule 
    requires that at the completion of any shift during which a portion of 
    a weekly examination is conducted, a record of the results be made. 
    This record must include any hazardous conditions found during the 
    examination and their locations, the corrective actions taken, and the 
    results and location of air and methane measurements. The record must 
    be made by the person making the weekly examination or a person 
    designated by the operator.
        The final rule includes a revision requiring that the results of 
    methane tests must be recorded as the percentage of methane measured by 
    the examiner. Previously, terms such as ``ok,'' ``low,'' or ``trace'' 
    were entered in record books as test results. The final rule clarifies 
    that such qualitative terms are not acceptable when examination 
    requirements specify the measurement of air quantity or methane levels 
    as such entries provide little useful information.
        The final rule requires that if the record is made by a person 
    other than the examiner, the examiner must verify the record by 
    initials and date by or at the end of the shift for which the 
    examination was made. As with other records required by this rule, the 
    records of weekly examinations may be kept either in secure books that 
    are not susceptible to alteration, or electronically in a computer 
    system so as to be secure and not susceptible to alteration. A detailed 
    discussion of record books and the use of computers to maintain records 
    can be found in the General Discussion of this preamble.
        Commenters suggested that the final rule only require the examiner 
    to record uncorrected hazardous conditions. MSHA is sensitive to 
    minimizing recordkeeping requirements and, for example, the final rule 
    requires only uncorrected defects found during the fan examination to 
    be recorded. However, the weekly examination record serves as a history 
    of the types of conditions that can be expected in the mine. When the 
    records are properly completed and reviewed, management can use them to 
    determine if the same hazardous conditions are occurring and if the 
    corrective action being taken is effective. Additionally, this record 
    can permit mine management, the representative of the Secretary, and 
    the representative of miners to better focus their attention during 
    examinations and inspections. The final rule adopts the proposal and 
    requires the examiner to record all hazardous conditions found and the 
    action taken to correct the hazardous condition.
        A variety of comments were received regarding the countersigning of 
    the records of weekly examinations by the mine foreman, and the time 
    permitted for countersigning. The final rule adopts the proposal that 
    the mine foreman or equivalent mine official must countersign the 
    record of the weekly examination by the end of the mine foreman's next 
    regularly scheduled working shift. The mine foreman is in a key 
    position of responsibility relative to the day-to-day operation of the 
    mine. It is essential for the health and safety of the miners that the 
    mine foreman be fully aware of the information contained in the 
    preshift examination reports so as to be able to allocate resources to 
    correct safety problems as they develop. Allowing until the end of the 
    mine foreman's next regularly scheduled working shift to countersign 
    the reports assures that the mine foreman is aware of the results on a 
    regular and timely basis.
        Numerous comments were received regarding the requirement of the 
    proposal for second level countersigning of the weekly examination 
    record by the mine superintendent, mine manager, or other mine official 
    to whom the mine foreman is directly accountable. A full discussion of 
    second level countersigning can be found in the General Discussion 
    section of this preamble.
        Paragraph (h) of the final rule also contains revisions to the 
    existing rule to allow for electronic storage of records. Paragraph (i) 
    requires that the records required by Sec. 75.364 be maintained at a 
    surface location at the mine for one year and be made available for 
    inspection by authorized representatives of the Secretary and the 
    representatives of 
    
    [[Page 9806]]
    miners. A discussion of comments concerning the use of computers to 
    maintain records can be found in the General Discussion of this 
    preamble.
        Under the final rule, the record of weekly examinations must be 
    countersigned by the mine foreman or equivalent mine official by the 
    end of the mine foreman's next regularly scheduled working shift. Based 
    on comments noting that traditional mine management structures have 
    changes at some operations, the final rule provides that an official 
    equivalent to mine foreman may countersign the records. The purpose of 
    this change is to require that when a mine foreman is not present in 
    the mine's management structure, an equivalent official must perform 
    this function. As with the existing standard, second level 
    countersigning by the mine superintendent is not required by the final 
    rule.
        The record of weekly examinations must be made in secure media not 
    susceptible to alteration. If records are made electronically, they 
    must be unalterable, shall capture dates and signatures, must be 
    accessible to representatives of the miners and the Secretary, and must 
    be capable of producing printouts. Further discussion of both the 
    issues of second level countersigning and acceptable record books or 
    electronic records can be found in the general discussion section of 
    this preamble.
        The proposal, at paragraph (b), would have added a requirement that 
    the certified person examine for noncompliance with mandatory safety or 
    health standards that could result in a hazardous condition. The 
    proposal drew considerable objection. Commenters objected to the 
    unlimited scope of the term ``noncompliance,'' the legal propriety of 
    recording noncompliance, and the additional examination time required 
    to determine noncompliance, the diversion of the examiner's attention 
    away from key safety conditions to minor compliance issues. Even so, 
    another commenter supported the proposal as necessary, suggesting that 
    the earlier rule was intended to require operators to assure full 
    compliance through the required examinations. The commenter correctly 
    noted that a requirement to examine for safety and health violations 
    was in effect from 1970 until 1992 when it was deleted.
        While the proposed standard appeared attractive in concept, the 
    majority of comments received indicate that the standard would result 
    in considerable confusion. In addition, it would be impractical to 
    define and adequately limit the scope of the requirement. Comments 
    consistently indicated confusion and misinterpretation of the 
    proposal's scope, offering a wide range of interpretations.
        As discussed in the preamble to the 1992 rule, most hazards are 
    violations of mandatory standards. Requiring the examiner to look for 
    all violations regardless of whether they involve a distinct hazard 
    could distract the examiner from the more important aspects of the 
    examination. Despite an attempt in the proposal to limit the scope of 
    the examination for noncompliance to situations that, ``could result in 
    a hazardous condition,'' commenters expressed a high level of 
    misunderstanding. Although a similar requirement existed between 1970 
    and 1992, MSHA generally did not broadly apply the standard. After 
    consideration of all comments and a review of the history since the 
    current standard became effective, MSHA concludes that the existing 
    standard is appropriate and best serves the objective of giving 
    examiners clear guidance for making effective examinations. 
    Accordingly, the proposal for examinations to include noncompliance 
    with mandatory safety and health standards is not adopted in the final 
    rule.
        Paragraph (b)(7) has been added to require that water pumps not 
    examined as part of a preshift examination conducted during the 
    previous 7 days be examined during the weekly examination. This 
    modification is an outgrowth of comments received in response to 
    proposed Sec. 75.360, which would have required examination of certain 
    pumps. As discussed in the preamble to Sec. 75.360, one commenter 
    persuasively argued that all pumps should be examined. Pumps that are 
    not preshift examined under the final rule are generally located in 
    remote areas of the mine. These pumps are appropriately examined on a 
    weekly basis.
    
    Section 75.370  Mine Ventilation Plan; Submission and Approval
    
        Mine ventilation plans are a long recognized means for addressing 
    safety and health issues that are mine specific. Individually tailored 
    plans, with a nucleus of commonly accepted practices, are an effective 
    method of regulating such complex matters as mine ventilation and roof 
    control. Section 75.370 requires that each mine operator develop and 
    follow a ventilation plan that is approved by MSHA and that is designed 
    to control methane and respirable dust in the mine. Section 75.370 
    further requires that the plan be suitable to the conditions and mining 
    system at the mine. In addition, Sec. 75.370 provides the procedures 
    for submittal, review and approval of the plan to assure that the plan 
    for each mine will address the conditions in that mine.
        In this final rule, MSHA revises the existing plan submission and 
    approval process to provide an increased role for the representative of 
    miners in the mine ventilation plan approval process. This revision is 
    consistent with the statutory purpose that miners play a role in safety 
    and health.
        The final rule redesignates existing paragraphs (b)(1) through (f) 
    as (c)(1) through (g), revises paragraphs (a)(3), (c)(1), and (f), and 
    adds a new paragraph (b). The proposal would have modified the existing 
    rule by providing that the representative of miners would receive a 
    copy of the proposed mine ventilation plan or proposed revisions at the 
    time of submittal to MSHA, and the approved plan upon approval by MSHA. 
    The existing rule provided that the submitted plan and the approved 
    plan were to be made available to the miners representative. Another 
    proposed change was to specify the length of time the submitted plan 
    and the approved plan would be posted at the mine. A new paragraph (b) 
    would allow for timely comments on the submitted plan from the miners 
    representative. Representatives of miners would receive written notice 
    of plan approval. The final rule, for the most part, adopts the 
    proposed rule. However, the final rule requires that the miners 
    representative be notified of the submittal of a mine ventilation plan 
    and revisions to a plan 5 working days prior to submittal and that the 
    representative of miners be provided with a copy of the plan upon 
    request. It also requires that MSHA provide a copy of miners'' 
    representative comments to the mine operator upon request.
        Final rule paragraph (a)(3) is divided into (a)(3)(i), (a)(3)(ii), 
    and (a)(3)(iii) and contains new requirements in (a)(1)(i) and 
    (a)(1)(iii). Paragraph (a)(3)(i) requires that the mine operator notify 
    the representative of miners that a mine ventilation plan or a plan 
    revision is to be submitted to the District Manager for approval. This 
    notification must be given at least 5 days prior to submission. 
    Paragraph (a)(3)(i) further requires that the operator provide a copy 
    of the plan or revision to the representative of miners at the time of 
    notification, if requested. Paragraph (a)(3)(ii) requires that the 
    proposed plan be made available for review by the representative of 
    miners, and paragraph (a)(3)(iii) requires that the proposed plan or 
    revision be posted on the 
    
    [[Page 9807]]
    bulletin board at the mine and remain posted until it is approved, 
    withdrawn, or denied.
        Commenters representing both operators and labor suggested that the 
    proposed plan or revision should be provided to the representative of 
    miners prior to being submitted to the district manager for approval. 
    One commenter suggested that the proposed plan or revision be provided 
    to the representative of miners 10 days prior to submittal and stated 
    that this could speed up the approval process by allowing the miners 
    affected to investigate the proposed change and by permitting the 
    operator and the representative of miners the opportunity to reconcile 
    differences prior to the operator's seeking approval. The commenter 
    pointed out that some existing wage agreements have adopted such a 
    requirement. The commenter suggested that the rule should also include 
    such a requirement because operators do not always comply with the 
    requirements of the agreement. This commenter further suggested that 
    there have been instances where plans have been revised and acted upon 
    before the representative of miners was aware that a revision was to be 
    made. Other commenters suggested that the proposed plan or revision be 
    provided 3 days prior to submittal. These commenters expressed 
    different reasons for the suggestion. One of these commenters stated 
    that the industry has historically maintained that since the plan is 
    submitted to the district manager for approval, and developed by the 
    mine operator, the requirement to provide copies to other parties is 
    contrary to the Mine Act. However, the commenters further stated that 
    their suggestion reflected an attempt to balance all interests and 
    resolve this matter.
        These comments are constructive and MSHA has used all of them to 
    fashion a final rule which is consistent with the statutory purpose and 
    responsive to the mining community. One commenter attempted to relate 
    the rule to terms of a wage and hour agreement. MSHA does not intend or 
    have authority to affect any wage and hour agreement. MSHA believes 
    that the involvement of the miners and their representative in the plan 
    approval process will improve the health and safety of the Nation's 
    coal miners. As suggested by commenters, miners who work under the mine 
    ventilation plan are often in the best position to know the effect of 
    proposed revisions. MSHA has long recognized the importance of input 
    from the miners and their representatives in the plan-approval process. 
    The preamble to the existing standard discusses the role of miners and 
    their representatives in the development of mine ventilation plans in 
    detail. MSHA continues to believe that miners have a stake in the 
    implementation of the ventilation plan at each mine.
        The final rule is consistent with the existing plan approval 
    process and does not change the process for developing and approving a 
    mine ventilation plan. The operator continues to be the party 
    responsible for developing the mine ventilation plan and MSHA continues 
    to be responsible for reviewing and approving the plan. The proposed 
    rule, in paragraph (a)(3)(i), would have required the operator to 
    provide a copy of a proposed mine ventilation plan or any proposed 
    revision to the representative of miners at the time of submittal to 
    MSHA. The final rule requires the operator to notify the representative 
    of miners of the submittal of the proposed plan or revision at least 5 
    working days prior to submittal to the district manager. In addition, a 
    copy is to be provided to the representative of miners upon request. In 
    most instances, this should provide sufficient time for a review of the 
    proposed plan or revision and a discussion between the operator and the 
    representative of miners over concerns that may exist.
        In response to comments, paragraph (a)(3)(i) is further revised in 
    the final rule to reflect that there are occasions when mine 
    ventilation plans must be submitted and reviewed within a very short 
    time frame. In response to a question during one of the public hearings 
    on the proposed rule, one commenter stated that miners understand that 
    at times situations may arise that necessitate an operator submitting a 
    plan or revision to MSHA that will not allow for the ten (10) day 
    provision for the representative of the miners.
        Paragraph (a)(3)(i) of the final rule requires that in the case of 
    a situation requiring immediate action on a plan revision, notification 
    of the revision shall be given, and if requested, a copy of the 
    revision shall be provided to the representative of miners by the 
    operator, at the time of submittal to the district manager. The final 
    rule does not include the recommendation of one commenter that the plan 
    or revision be provided to the representative of miners before 
    submittal because to so require could delay approval of a change 
    necessary to health and safety. Questions will undoubtedly arise 
    relative to what constitutes a situation requiring expedited action. 
    MSHA does not believe that it is possible or appropriate to set forth 
    all circumstances which would be covered by the standard. Should such a 
    situation arise, it would be handled by the district manager on a case 
    by case basis. Generally, the district manager would be guided by 
    whether the condition, if uncorrected, could result in a health or 
    safety hazard or an imminent stoppage of production in the mine or an 
    area of the mine.
        Paragraph (a)(3)(ii) of the final rule retains the requirement that 
    a copy of the proposed plan or any proposed revisions be made available 
    for inspection by the representative of the miners. Although some 
    commenters thought this was superfluous in light of the requirement in 
    paragraph (a)(3)(i), MSHA believes that this requirement facilitates 
    the overall approval process.
        Paragraph (a)(3)(iii) of the final rule retains the existing 
    requirement that copies of the proposed plan and proposed revisions be 
    posted on the mine bulletin board and clarifies that posting is 
    required at the time of submittal. MSHA believes that the posting 
    requirement is necessary to assure that all miners at a mine will have 
    the opportunity to review the proposed plan or revision and provide 
    input during the review process. One commenter suggested that proposed 
    plans or proposed revisions be required to remain posted for only 30 
    days from the time of submittal so as not to ``clutter up the bulletin 
    board.'' This suggestion has not been included in the final rule 
    because the mine ventilation plan impacts miners'' safety and health 
    and it is important for miners to know which plan provisions are in 
    effect versus those which have not been approved. Another commenter 
    suggested that proposed plans and revisions be posted 10 days prior to 
    submittal to MSHA. This recommendation has not been included in the 
    final rule to assure that there is no confusion between plans that are 
    approved and proposed provisions awaiting MSHA approval. To require 
    posting of proposed plan revisions prior to submission to MSHA would 
    create another category of mine ventilation plans which could result in 
    unnecessary confusion. This is particularly true since the 
    representative of miners will have the plan at least 5 days prior to 
    submittal. Because there are occasions where a representative of miners 
    does not feel it is necessary to review a plan or revision, the rule 
    only requires the operator to provide a copy of the plan or revision 
    upon request.
        Paragraph (b) of the final rule specifies procedures that the 
    representative of miners may use to provide input in the mine 
    ventilation plan review process. Under the final rule, the 
    representative of miners may 
    
    [[Page 9808]]
    submit comments on the proposed plan or revisions to the plan to the 
    district manager for consideration. Recognizing that in some instances 
    a decision relative to the approval or denial of a revision must be 
    made in a short time frame, the final rule requires that comments be 
    made in a ``timely manner.'' MSHA has not defined ``timely manner'' but 
    would consider it to be a period of time that does not unnecessarily 
    delay the approval process. The district manager will continue to be 
    available to discuss with the representative of miners all aspects of 
    the plan as they affect miners' health and safety at any time during or 
    following approval or denial of a proposed plan or revision. Commenters 
    suggested that the representative of miners be given a deadline for the 
    submission of comments similar to the time frame established in 
    paragraph (a)(3)(i) for the operator to provide copies of proposed 
    plans and revisions to the representative of mines. In support of this 
    recommendation, these commenters stated that unlimited time could 
    unnecessarily delay the approval process. This recommendation is not 
    included in the final rule due to the complexity of some plans and 
    revisions. MSHA's goals are for a process that includes both timely 
    review and approval and opportunity for input from miners and the 
    Agency believes both goals can be accomplished under the final rule. 
    MSHA does not believe that this provision will unnecessarily delay the 
    plan approval process since the final rule, like the proposal, requires 
    comments to be submitted in a timely manner.
        One commenter suggested that comments submitted by the 
    representative of miners to the district manager as part of the plan 
    approval process should be provided to the operator. MSHA would expect 
    that during the five day period before the plan is submitted to the 
    district manager the operator and the representative of miners will 
    discuss the plan and inform the other of their respective positions. 
    MSHA would encourage the representative of miners to provide a copy of 
    their comments to the operator prior to submitting them to MSHA. 
    However, to assure that all parties to the plan approval process are 
    aware of each others position paragraph (b) of the rule provides that 
    the district manager will provide the operator with these comments upon 
    request.
        Paragraph (c)(1) of the final rule is unchanged from the proposal 
    and retains the existing requirement that the district manager notify 
    the operator in writing of the approval or denial of a proposed plan or 
    proposed revision. Paragraph (c)(1) adds a requirement that a copy of 
    this notification be sent by the district manager to the representative 
    of miners. This provision is intended to assure that the representative 
    of miners is kept informed of the status of the plan approval. One 
    commenter pointed out that quite often, plan provisions are modified 
    during the review process and the final approved plan may be different 
    from that which was originally submitted. This commenter suggested that 
    when a change is made to a submission, the representative of miners 
    should be notified of the intended change and afforded the opportunity 
    to comment. MSHA agrees that changes to proposed plans do occur during 
    the review process. Consistent with MSHA's philosophy that all parties 
    to the plan approval process need to be aware of the status of a 
    proposed plan or revision, MSHA would expect that the operator would 
    inform the representative of miners of changes to the original 
    submittal. However, to require that notification be provided for each 
    and every change, no matter how minor, could effectively stop the plan 
    review and approval process. Therefore, the final rule does not adopt 
    the suggestion of the commenter. Some commenters interpreted paragraph 
    (c)(1) as requiring the district manager to provide a copy of the 
    approved plan to the representative of miners. Paragraph (c)(1) only 
    requires that the district manager provide to the representative of 
    miners a copy of the notification of approval or denial that is sent to 
    the operator.
        Proposed paragraphs (f)(1), (f)(2) and (f)(3) are adopted in the 
    final rule. Paragraph (f)(1) is new and requires the operator to 
    provide the representative of miners with a copy of the plan or 
    revision following notification of approval, if requested. This 
    facilitates review of the plan or revision by the representative of 
    miners. Also, the final rule continues in paragraphs (f)(2) and (f)(3) 
    the existing requirements that the approved plan or revision be made 
    available for inspection by the representative of miners and be posted 
    on the mine bulletin board. Like the proposal, a new requirement in 
    paragraph (f)(3) also requires that an approved plan or revision must 
    be posted within 1 working day of notification of the approval and must 
    remain posted for the period that the plan is in effect. This helps to 
    assure that the miners themselves, as well as the representative of 
    miners, are aware of the provisions of the mine ventilation plan once 
    it is approved.
        Commenters both supported and opposed paragraph (f). Those in 
    opposition suggested that some of the requirements were unnecessary in 
    light of other requirements in the standard. Those supporting the rule 
    suggested that the operator should be required to provide a copy of the 
    approved plan or revision to the representative of miners and to make 
    it available within 24 hours of notification of approval. Other 
    commenters stated that mine ventilation plan approvals are sometimes 
    sent to the company offices and not necessarily to the mine. They 
    stated that in these cases, there could be a delay in copies of the 
    approved plan or revision reaching the mine. MSHA crafted the final 
    rule in light of the existing paragraph (d) which requires that 
    operators instruct persons affected by the mine ventilation plan or its 
    revision prior to implementation. Changes to the plan do occur during 
    the approval process; MSHA would expect that the plan or revision would 
    be available to the person conducting the required training and, 
    therefore, would be provided to the representative of miners.
        One commenter suggested that, because the approved plan is required 
    to be made available for inspection by the representative of miners, 
    there is no need for the plan or revision to be posted on the bulletin 
    board. This commenter identified some logistical problems associated 
    with posting of plans stating that removal of the plan from the 
    bulletin board could be a problem.
        This same commenter proposed that notification of the miners of a 
    revision to the mine ventilation plan should be the responsibility of 
    the representative of miners. MSHA does not agree that making the plan 
    available for inspection by the representative of miners is an adequate 
    substitute for posting of the plan or revision so as to make it 
    available to all miners at all times. Nor does MSHA agree that the 
    responsibility for assuring that miners are aware of the requirements 
    of the plan is the proper function for the representative of miners. 
    MSHA recognizes that difficulties can exist in assuring that the 
    approved plan or revision is posted, however the safety benefits of 
    having the plan available to the persons affected by its provisions far 
    outweigh any logistical problems.
    
    Section 75.371  Mine Ventilation Plan; Contents
    
        Section 75.371 sets forth the information that the operator must 
    include in the mine ventilation plan. Because the plan deals with 
    situations 
    
    [[Page 9809]]
    unique to a mine, the general rules applicable in other standards do 
    not fit. For the convenience of the reader, the standard that sets out 
    the general rule or provides for an option to include a provision in a 
    plan will generally cross reference to the appropriate paragraph in 
    Sec. 75.371.
        MSHA proposed revisions to existing paragraphs (b), (s), (z) and 
    (bb) of Sec. 75.371 and reproposed existing paragraph (r). MSHA's final 
    rule adopts the proposal for paragraphs (s), (z) and (bb). MSHA revises 
    its proposed paragraph (r) to make conforming changes with other 
    provisions. Finally, the final rule retains the existing language for 
    paragraph (b).
        As stated in the General Discussion section of this preamble, 
    provisions concerning the installation and removal of mechanized mining 
    equipment that were promulgated in May of 1992 as part of the safety 
    standards for underground coal mine ventilation were reproposed in May 
    of 1994 as part of this rulemaking for the purpose of receiving and 
    giving full consideration to all pertinent comments on this issue. 
    Paragraph (r) of the final rule is one of the provisions that was 
    reproposed. Section 75.325(d) of the final rule requires that areas 
    where mechanized mining equipment, including longwall equipment, is 
    being installed and removed be ventilated. Paragraph (r) of Sec. 75.371 
    requires that the quantity of air that will be provided be included in 
    the mine ventilation plan. Most commenters either supported the 
    provision, citing the explosion at the William Station Mine, or stated 
    that the standard was originally promulgated inappropriately and did 
    not substantively comment on the requirement. One commenter suggested 
    that the quantity of air specified in the plan under paragraph (r) 
    should represent the minimum quantity that will be provided and the 
    location specified should be identified as what would be typical so as 
    to give the mine the flexibility to adapt to varying mine conditions. 
    This recommendation is consistent with MSHA's intent and MSHA has 
    included it in the final rule to help clarify the rule.
        One commenter suggested that the ventilation scheme shown in the 
    plan should be representative of the method of ventilation to be used. 
    MSHA agrees that the mine ventilation plan should include a method of 
    ventilation that is representative of that used in the mine. However, 
    MSHA has not adopted this suggestion since the plan must be specific 
    enough so that the operator, the miners, the representative of miners, 
    and MSHA are assured that all areas are being adequately ventilated.
        Paragraph (r) of the final rule requires that the mine ventilation 
    plan include the location where air quantities will be provided, and 
    the ventilation controls that will be used to provide these quantities. 
    This language was included in the reproposed provision and in 
    Sec. 75.325(d), which requires that the quantity of air that will be 
    provided during the installation and removal of mechanized mining 
    equipment, the location where this quantity will be provided, and the 
    ventilation controls that will be used, be included in the mine 
    ventilation plan. In reproposing paragraph (r), MSHA inadvertently 
    excluded from Sec. 75.371(r) the requirement relative to the location 
    where the air quantity is provided. The final rule has been modified in 
    Sec. 75.371(r) to conform to the requirements of Sec. 75.325(d).
        The final rule revises existing paragraph (s) to conform to changes 
    in Sec. 75.362(d)(1)(iii). The final rule deletes the portion of 
    existing Sec. 75.362(d)(2) which requires that the mine ventilation 
    plan include the location of tests which are to be made closer to the 
    working face than the last permanent roof supports using extendable 
    probes or other acceptable means. The final rule in paragraph 
    (d)(1)(iii) requires that the mine ventilation plan specify the 
    frequency and location of the methane tests if required more often than 
    20 minutes by Sec. 75.362(d)(1)(iii). One commenter suggested adding 
    the words, ``or at other locations and frequencies if approved by the 
    district manager and contained in the ventilation plan.'' The suggested 
    clarification is not necessary and has not been adopted in the final 
    rule.
        The final rule revises paragraph (z) to conform to Sec. 75.364(a). 
    Section 75.364(a) addresses the measurements to be made to evaluate the 
    effectiveness of bleeder systems and the ventilation of worked-out 
    areas during the weekly examination. The final rule requires that the 
    locations where these measurements are made or alternative methods of 
    providing these evaluations be included in the mine ventilation plan. 
    One commenter suggested that the locations where air measurements are 
    made should not be required in the mine ventilation plan. The commenter 
    made a similar suggestion relative to the requirement in Sec. 75.364 
    that air measurements be made to evaluate the ventilation of worked-out 
    areas and determine the effectiveness of bleeder systems. According to 
    the commenter, since no specific air volume is required it is not 
    necessary to measure the volume present. The measurement of air 
    quantity, as well as the other measurements required by the existing 
    standard, are essential to evaluate the ventilation of worked-out areas 
    and determine the effectiveness of bleeder systems. The final rule, 
    therefore, does not include the suggested changes in either Sec. 75.364 
    or Sec. 75.371(z).
        Another commenter suggested that since the current standards do not 
    require a specific volume of air in bleeder entries, it is unnecessary 
    to measure the air volume. Proper evaluation of the effectiveness of a 
    bleeder system can only be achieved by comparison of measurements taken 
    in the bleeder system. In most instances, one of the most important 
    measurements is the air quantity at strategic points in the bleeder 
    system. Therefore, the final rule includes the proposed requirement 
    that the locations where air quantity measurements will be made in the 
    bleeder system be specified in the mine ventilation plan.
        Existing paragraph (bb) requires that the location of ventilating 
    devices used to control air movement through worked-out areas be 
    included in the mine ventilation plan. The final rule reinstates a 
    requirement contained in the previous regulation, that the location and 
    sequence of construction of proposed seals also be indicated. This 
    requirement is consistent with Sec. 75.334(e) which requires that the 
    sequence of construction of seals be specified in the mine ventilation 
    plan. Some commenters on paragraph (bb) and Sec. 75.334(e) suggested 
    that proper sequencing of seals can change due to mining conditions and 
    should not be made a part of the mine ventilation plan. Another 
    commenter suggested that because the time to get a plan approved can be 
    lengthy, it may even create unnecessary hazards. Proper sequencing of 
    seal construction is necessary for effective ventilation during 
    sealing. Therefore, the final rule requires the location and sequence 
    of the construction of seals be specified and approved in the mine 
    ventilation plan. If a delay in seal construction will result in a 
    hazard to miners, the review and approval of the plan can be expedited 
    as explained in the preamble discussion of Sec. 75.370.
        One commenter on paragraph (bb) suggested that the locations of 
    stoppings, regulators, and bleeder connector entries are better shown 
    on the mine map with a notation that it is subject to approval under 
    Sec. 75.371. The existing standard permits appropriate information 
    required under Sec. 75.371 to be shown on the map required by 
    Sec. 75.372. This is explained in the preamble discussion for existing 
    Sec. 75.371. MSHA recognizes that some of 
    
    [[Page 9810]]
    the information required to be submitted under Sec. 75.371 is best 
    shown on a map. Rather than require additional maps, this information 
    may be shown on the Sec. 75.372 map. When shown on the Sec. 75.372 map, 
    only that portion of the map that contains information required under 
    Sec. 75.371 is subject to approval by the district manager.
        The proposal would have revised paragraph (b) to reflect the 
    proposed changes in paragraphs (c) and (d) of Sec. 75.312 allowing 
    alternative testing methods for main mine fan automatic closing doors 
    and fan signals. Because the final rule does not include the proposed 
    changes to Sec. 75.312(c) and (d), final rule Sec. 75.371(b) conforms.
    
    Section 75.372  Mine Ventilation Map
    
        The mine ventilation map provides a basis for understanding how a 
    particular coal mine is ventilated. An accurate and up to date map of 
    the mine enables the operator and MSHA to review the mine's ventilation 
    plan to determine the appropriateness of the ventilation system to the 
    conditions in the mine. Only through a thorough understanding of the 
    ventilation system can the operator and others determine whether the 
    system is capable of preventing methane accumulations, possible 
    explosions, and high levels of respirable dust. Generally, Sec. 75.372 
    requires that the necessary information be provided on the map.
        The final rule revises existing paragraph (b)(3) and adds new 
    paragraphs (b)(19) and (b)(20). Paragraph (b)(3) addresses which 
    adjacent workings must be shown on the mine map. The final rule, like 
    the proposal, requires all known adjacent workings within 1,000 feet of 
    existing or projected mine workings to be shown on the mine map, 
    regardless of whether the workings are located on mine property or on 
    adjacent property. The existing rule required that only the adjacent 
    workings within 1,000 feet be shown if they are on mine property.
        MSHA has concluded that it is necessary to require that the mine 
    ventilation map include all known workings located in the same coalbed 
    within 1,000 feet of existing or projected workings, regardless of 
    whether the workings are located on the mine property. Hazards, such as 
    methane and water accumulations and irrespirable atmospheres, exist in 
    old workings whether located on mine property or not. MSHA also notes 
    that this revision makes paragraph (b)(3) consistent with existing 
    paragraph (h) of Sec. 75.1200, Mine map. Paragraph (h) of Sec. 75.1200 
    requires that the mine map show all adjacent mine workings within 1,000 
    feet. Like the previous standard, this revision would assure that all 
    adjacent mine workings appear on the Sec. 75.372 map in those cases 
    where operators do not use a Sec. 75.1200 map for their required 
    submission.
        One commenter suggested that this requirement not be included 
    because mine operators have no legal obligation or authority to force 
    an adjacent land owner to provide the required information. MSHA 
    recognizes that the mine operator may, in some instances, have 
    difficulty obtaining this information. The hazards that exist within 
    abandoned mines, however, warrant such a requirement. Additionally, as 
    noted previously, this requirement is consistent with the requirements 
    of Sec. 75.1200(h) and will, therefore, impose no additional burden on 
    the operator. Agency experience reveals that the existing standard, 
    Sec. 75.1200(h), has not proven to be practically difficult for 
    compliance. In addition, this information would be available to the 
    miners and would enhance their understanding of the ventilation system 
    and aid them in the event of an emergency.
        Another commenter suggested that the rule explicitly require that 
    all mine workings, including workings from auger mining, highwall 
    mining and strip mining, be shown on the map. This recommendation has 
    not been included in the final rule because MSHA believes that the 
    final rule is clear and requires any workings from other mines, such as 
    strip, auger and similar workings, to be shown if they are in the same 
    coalbed and are within 1,000 feet of existing or projected mine 
    workings.
        Proposed paragraph (b)(19) is adopted in the final rule. The 
    proposal was drafted in response to comments received at public 
    meetings. It reinstates the requirement in the previous standard that 
    the mine map include the entry height, velocity and direction of the 
    air current at or near the midpoint of each belt flight where the 
    height and width of the entry are representative of the belt haulage 
    entry. Paragraph (b)(19) of the final rule should assist the examiner 
    in rapidly determining whether the air is flowing in its normal 
    velocity and direction during examination of the belt entry required 
    elsewhere in subpart D. One commenter suggested that this requirement 
    is redundant because the mine ventilation plan already requires that 
    this be ``illustrated''. MSHA does not agree that the requirement is 
    redundant since there is no such requirement in the mine ventilation 
    plan.
        MSHA emphasizes that like much of the information required to be 
    shown on the ventilation map, this information would not be subject to 
    approval. When shown on the Sec. 75.372 map, only that portion of the 
    map that contains information required under Sec. 75.371 is subject to 
    approval by the district manager. The information required by paragraph 
    (b)(19) does not fit this criteria and therefore is not subject to 
    approval by the district manager.
        As explained in the discussion of Sec. 75.301, instances have 
    developed where operators direct air from an intake air course to 
    ventilate shops, electrical installations, or for other purposes, and 
    this air is then coursed to the surface and is not used to ventilate 
    working places. Under one interpretation of the existing definition, 
    because this air has not ventilated a working place or a worked-out 
    area, the air course cannot be considered a return air course. In these 
    instances, the final rule in Sec. 75.301 expressly permits the 
    redesignation of the affected portion of the air course as a return air 
    course. Because it is important that personnel, including examiners, 
    the miners' representative, and representatives of the Secretary, know 
    which air courses have been redesignated, the final rule requires that 
    these air courses be shown on the map. Paragraph (b)(20) requires that 
    the location of redesignated air courses be shown on the ventilation 
    map. Commenters were supportive of this provision.
    
    Section 75.380  Escapeways; Bituminous and Lignite Mines
    
        When a fire, explosion or other emergency necessitates an immediate 
    evacuation of a mine, the designated route for miners to leave the mine 
    is the escapeway. The escapeway should be appropriately located and 
    designed to be free of obstructions and hazards to assure safe passage 
    from the hazardous underground environment. The final rule addresses 
    requirements for escapeways. Paragraphs (b)(1) and (b)(2) set forth the 
    requirements for the location of the escapeway when installing and 
    removing mechanized mining equipment. Paragraphs (d)(3) through (d)(5) 
    deal with the minimum dimensions of escapeways. Paragraph (f) addresses 
    the equipment that can be used in escapeways and the requirements for 
    fire suppression systems on this equipment. Finally, paragraph (i) sets 
    the minimum slope of an escapeway.
        The final rule republishes existing paragraphs (b)(1) and (b)(2) 
    and revises paragraph (d)(3) through (d)(5), (f) and (i)(2).
        Sections 75.380 (b)(1) and (b)(2) of the final rule deal with 
    escapeways on 
    
    [[Page 9811]]
    working sections and areas where mechanized mining equipment is being 
    installed or removed. MSHA adopts the proposal in the final rule. An 
    in-depth discussion of the proposal of provisions concerning the 
    installation and removal of mechanized mining equipment is presented in 
    the General Discussion section of this preamble.
        MSHA specifically solicited comments on those portions of the 
    proposal dealing with the installation and removal of mechanized mining 
    equipment, including paragraphs (b)(1) and (b)(2) of Sec. 75.380. These 
    paragraphs require that an escapeway be provided to areas where 
    mechanized mining equipment is being installed or removed. Only one 
    substantive comment was received. The commenter suggested that the 
    location of the beginning of the escapeway during equipment 
    installation and removal should be specified in the mine ventilation 
    plan to minimize the potential for congestion during movement of heavy 
    equipment. The commenter stated that the proposal would eliminate all 
    access to a longwall during the installation or removal of the longwall 
    equipment except for the face crosscut, and lead to accidents.
        MSHA believes that the location where the loading point will be 
    installed and where the loading point was last located prior to removal 
    are easily identifiable and offer the best choice. The suggestion of 
    the commenter has not been adopted in the final rule. In addition, the 
    commenter noted that mobile equipment was needed during the 
    installation and removal of longwalls; this equipment can be used in 
    the escapeway if properly attended and protected with proper fire 
    suppression.
        As with the existing rule, paragraph (d)(3) of the final rule 
    generally requires escapeways to be maintained to a height of 5 feet 
    from the mine floor to the mine roof, excluding the thickness of any 
    roof support. To accommodate mines in low seams, the rule provides that 
    where the coalbed is less than 5 feet, the escapeways shall be 
    maintained at least to the height of the coalbed. As in the past, 
    convergence, the reduction in entry height due to roof sag or floor 
    heave, which occurs as a natural geologic process, will be excluded 
    when determining escapeway height unless it would impede the escape of 
    miners, including disabled persons, in the event of an emergency. The 
    final rule modifies (d)(3) to provide that in areas of mines where 
    escapeways pass through doors or in areas of mines developed before 
    November 16, 1992 where escapeways pass across or under overcasts or 
    undercasts, the height of the escapeway may be less than 5 feet 
    provided the height is sufficient to enable miners, including disabled 
    persons, to escape quickly in an emergency. It was brought to the 
    attention of MSHA by one commenter that in some instances the removal 
    of roof support or the lowering of the tops of overcasts may be 
    necessary to provide the 5-foot height required by the existing rule. 
    It has been suggested that this could result in a diminution of safety.
        One commenter suggested that escapeways should be 6 feet in width 
    and 5 feet in height without exception. This suggestion has not been 
    adopted in the final rule. Under the previous rule, escapeway 
    dimensions were addressed through criteria and operators routinely 
    requested and received approval for lesser dimensions than that in 
    criteria based on a performance test referred to as a ``stretcher 
    test.'' As applied, this test required 4 persons to carry a fifth 
    person on a stretcher through the area in question. The purpose of the 
    ``stretcher test'' was to demonstrate that the lesser dimension would 
    not delay escape. The final rule permits lesser escapeway heights and 
    widths under specific circumstances provided the height and width 
    maintained enable miners to escape quickly in an emergency. The final 
    rule requires that when there is a need to determine whether sufficient 
    height or width is provided, MSHA may require a stretcher test where 4 
    persons carry a miner through the area in question on a stretcher.
        This commenter suggested that the results of a stretcher test could 
    be manipulated by having the most fit miners carry the smallest miner. 
    MSHA continues to believe that the stretcher test is appropriate. 
    MSHA's experience is that the stretcher test provides a good measure of 
    the ability of miners to escape.
        Since the escape of miners is not impeded, the demonstration that 
    there is no delay in escape assures that there is no reduction in 
    safety.
        MSHA received similar comments regarding the dimensions of 
    escapeways developed on or after November 16, 1992, (the effective date 
    of the existing rule). Commenters suggested that where these escapeways 
    pass across or under overcasts or undercasts, the height of the 
    escapeway should be permitted to be less than 5 feet provided the 
    height is sufficient to enable miners, including disabled persons, to 
    escape quickly in an emergency situation. This suggestion is not 
    adopted in the final rule since sufficient clearance should have been 
    provided in these escapeways through proper planning and engineering. 
    Also, MSHA's experience does not reveal any compliance problems 
    associated with the standards since November 1992.
        One commenter recommended changing the phrase ``disabled persons'' 
    in paragraph (d)(3) to ``injured persons.'' In support of this 
    recommendation, the commenter stated that the phrase is intended to 
    include persons who may be injured but not necessarily disabled. MSHA 
    does not believe that the change is needed since there are many 
    situations that occur underground that can result in a person being 
    injured but not severely enough to need assistance (i.e. disabled) to 
    be transported from the mine. An escapeway that will permit the 
    transport of disabled persons, i.e. the more severely injured persons, 
    can be expected to accommodate persons with lesser injuries. The term 
    disabled with respect to the concept of injured has existed in the 
    regulations for over 25 years and MSHA is not aware of any problems 
    with its use.
        Questions arose during informational meetings regarding the 
    requirements for the height of doors in escapeways. The final rule, 
    like the proposal, permits door heights of less than 5 feet under 
    certain conditions. Under the previous rule, escapeway dimensions, 
    including door heights, were addressed through criteria and operators 
    routinely requested and received approval for lesser dimensions than 
    that in criteria based on a performance test referred to as a 
    ``stretcher test.'' Under the final rule, door heights of less than 5 
    feet are permitted provided the operator can demonstrate that persons, 
    including disabled persons, can escape without delay. The method of 
    demonstration would be the stretcher test, the same as for the 
    escapeway. Additionally, there are normally few doors in an escapeway 
    and the distance traversed in a door is very short. Passing the 
    stretcher test assures that there would be no diminution of safety 
    under the new provision. Also, since significant pressure differentials 
    can exist in escapeways, doors which are less than 5 feet are easier to 
    open.
        Paragraph (d)(4) of the existing rule requires the escapeways be 
    maintained at least 6 foot wide with some exceptions. Widths of less 
    than 6 feet are permitted in either the primary or the alternate 
    escapeway in instances where supplemental roof support is necessary and 
    where the route of travel passes through doors or other permanent 
    ventilation controls. In both cases, existing paragraph (d)(4) requires 
    that the escapeway be at least 4 feet wide. Under the final rule, 
    paragraph (d)(4)(iii) permits the alternate 
    
    [[Page 9812]]
    escapeway to be less than 4 feet wide under certain conditions.
        Paragraph (d)(4)(iii) applies to the alternate escapeway only and 
    allows the escapeway width to be less than 4 feet for the same 
    conditions addressed in paragraphs (i) and (ii) if it can be 
    demonstrated that sufficient width is maintained to enable persons, 
    including disabled persons, to escape quickly in an emergency. The 
    conditions that could warrant lesser widths are the locations where the 
    alternate escapeway passes through doors or other permanent ventilation 
    controls, including constructed approaches to permanent ventilation 
    controls and facilities addressed in paragraph (d)(6), or where 
    supplemental roof support is required.
        One commenter stated that the alternate escapeway should be 
    maintained at a minimum width of 4 feet without exception and noted 
    that on several occasions miners have been forced to use the alternate 
    escapeway in emergencies. The commenter noted that it could be 
    difficult to transport an injured person on a stretcher at widths under 
    4 feet. The final rule requires that when there is a need to determine 
    whether adequate width is provided, the stretcher test would be 
    applied.
        Under the previous rule, approval had been granted for reduced 
    escapeway widths based on the stretcher test. These approvals were due 
    to the need to provide additional roof support and, in some cases, the 
    need for passage through ventilation controls. Additionally, as newer 
    portions of a mine age and require additional roof support, the final 
    rule allows widths of less than 4 feet in the alternate escapeway where 
    this roof support exists, provided the stretcher test is passed. MSHA 
    believes this approach achieves the intended result of the standard 
    while at the same time addressing the safety issues of providing 
    necessary supplemental roof support and permitting travel in the 
    alternate escapeway.
        The preamble to the proposal stated that under the existing 
    standard Sec. 75.380(d)(4) mobile equipment should not be considered 
    when determining escapeway width unless the equipment has been 
    permanently abandoned in the escapeway or would be obstructing the 
    escapeway for a significant portion of a shift. Commenters objected 
    that this interpretation would be unduly restrictive and impractical. 
    Commenters noted that certain parked mobile equipment would enhance 
    miner safety where the equipment could be used to transport people out 
    of the mine in the event of an emergency.
        Experience under the existing and the previous rule indicates that 
    track-mounted and rubber-tired equipment which could be used for 
    evacuation should be excluded when determining escapeway widths. Track-
    mounted supply cars enhance safety by providing a readily available 
    supply of rock dust, roof support material, and other essential safety 
    related material. Section 75.214 requires that a supply of 
    supplementary roof support material and the tools and equipment 
    necessary to install the materials be available at a readily accessible 
    location on each working section or within 4 crosscuts of each working 
    section. In contrast, the Agency received comments that escapeways 
    should be maintained at least 6 feet in width except in rare cases 
    where roof supports could reduce the width to no less than 4 feet over 
    a limited distance.
        The final rule takes a practical approach, preserving the 
    requirement that escapeways must be of sufficient width to enable 
    miners, including disabled persons, to escape quickly in an emergency. 
    The final rule also recognizes that certain necessary mining and 
    transportation equipment is located on and near working sections. For 
    example, necessary supply cars containing safety related material like 
    rock dust, roof support, ventilation control construction material, 
    etc., is allowable. Additionally, longwall section equipment commonly 
    includes, but may not be limited to, starter box, water pump, section 
    belt tailpiece and takeup assembly, section transformer, and emulsion 
    pump. Because this equipment is necessary to the operation of the 
    longwall, it also is permitted to be in the escapeway near the working 
    section under the final rule. In continuous miner sections as well as 
    longwall sections, mantrips and personnel transportation equipment, 
    which could be utilized in an emergency evacuation, is allowable. The 
    final rule would not prohibit this equipment in escapeway entries on or 
    near working sections. The rule would require, however, that sufficient 
    clearance be maintained to permit rapid escape.
        This aspect of the final rule maintains the historical approach 
    taken to addressing issues of clearance in the confined environment of 
    underground coal mines. The final rule, while permitting reduced 
    dimensions near working sections as discussed above, requires that the 
    escapeways always be maintained of sufficient width to enable miners, 
    including disabled persons, to escape quickly in an emergency. As 
    discussed elsewhere in this preamble, the Agency will assess the 
    adequacy of escapeway widths in such areas by means of the stretcher 
    test to assure that the width is sufficient to enable miners, including 
    disabled persons, to escape quickly in an emergency.
        Like the proposal, the final rule in paragraph (d)(5) revises the 
    existing language dealing with the location of escapeways. It provides 
    that escapeways shall be located to follow the most direct, safe and 
    practical route to the nearest mine opening suitable for the safe 
    evacuation of miners. A question arose during an informational meeting 
    as to whether MSHA intended that the existing rule eliminate the 
    requirement that escapeways be routed to the ``nearest mine opening.'' 
    It was not MSHA's intent to change this requirement from the previous 
    standard. The existing requirement that the escapeway follow the most 
    direct route to the surface would, in fact, require the route to go to 
    the nearest mine opening. However, to eliminate any confusion that may 
    exist, the final rule revises paragraph (d)(5) and adopts language 
    similar to that in previous regulation, Sec. 75.1704-2(a), that is, 
    that the escapeway must follow the most direct, safe and practical 
    route to the nearest mine opening suitable for the safe evacuation of 
    miners.
        One commenter stated that escapeways should not be permitted to 
    pass an opening to be routed to a more distant opening. Another 
    commenter stated that the nearest mine opening may not always be the 
    safest due to roof conditions or other factors. MSHA acknowledges that 
    the nearest mine opening may not always be the safest route to the 
    surface. A number of factors affect whether or not the safest, most 
    direct, practical route has been selected. These factors include roof 
    conditions, travel height, fan location, physical dimensions of the 
    mine opening, and similar considerations. For example, if bad roof 
    conditions are present along the shortest direct route and those roof 
    conditions are beyond reasonable control, then an alternate ``safe'' 
    route designated by the mine operator may be appropriate. However, the 
    presence of roof falls does not necessarily indicate that the 
    passageway would not be suitable for evacuation if it is reasonable to 
    rehabilitate the area. By way of another example, where coal seam 
    thickness varies to the extreme, the shortest route may be through 
    lower coal, making travel relatively slow and difficult. An alternate 
    route through a high passageway may permit easier travel. Such an 
    alternate route, although longer, may be more practical and therefore 
    may be more appropriate. 
    
    [[Page 9813]]
    Similarly, there can be other instances where the ``nearest mine 
    opening'' may not be suitable for safe evacuation of miners. For 
    example, an old mine shaft may not be safe for travel because of badly 
    deteriorated conditions, such as a deteriorated shaft lining or 
    deteriorated timbers, even though the shaft is still suitable for mine 
    ventilation purposes.
        As with the existing standard, mine development projections do not 
    have to be altered to provide additional rooms, entries, or crosscuts 
    for the sole purpose of providing a passageway to the nearest mine 
    opening. However, the construction of ventilation controls such as 
    stoppings, overcasts and undercasts, or the installation of an escape 
    facility may be required to provide the most direct, safe and practical 
    route to the surface.
        One commenter suggested that MSHA should require an escapeway plan 
    to be approved by the MSHA district manager to assure the most direct 
    route to the surface. Existing standards require that escapeways be 
    shown on the ventilation map. In addition, as with other regulations, 
    inspectors assess whether escapeways follow the most direct, safe and 
    practical route to the surface during each regular inspection. 
    Accordingly, MSHA does not believe that an additional plan is 
    necessary.
        Existing paragraph (f) establishes the requirements for ventilation 
    of the primary escapeway and identifies which equipment can be operated 
    in the primary escapeway and the fire suppression requirements for this 
    equipment. The final rule, like the proposal, modifies paragraph (f) to 
    explicitly identify the equipment that is not permitted in the primary 
    escapeway and to specify the types of fire suppression systems that are 
    to be used and the conditions under which each is to be used on 
    equipment permitted in the primary escapeway. This is done by replacing 
    existing paragraphs (f)(1) and (f)(2) with paragraphs (f)(1) through 
    (f)(7) in the final.
        Existing paragraph (f)(1) requires that one escapeway that is 
    ventilated with intake air be designated as the primary escapeway and 
    prohibits certain equipment from being used in the primary escapeway in 
    areas developed after November 15, 1992. Further, paragraph (f)(1) 
    requires fire suppression systems on mobile equipment that is operated 
    in the primary escapeway. The final rule transfers the part of existing 
    paragraph (f)(1) that specifies the area of the primary escapeway 
    affected to paragraph (f)(2).
        The existing rule limited the installation or use of certain 
    equipment in areas of the primary escapeway developed after November 
    15, 1992. Paragraph (f)(2) of the final rule modifies the existing rule 
    for clarity and expands the application of certain requirements 
    contained in paragraphs (f)(3) through (f)(7) to the entire primary 
    escapeway except those areas of the primary escapeway developed prior 
    to March 30, 1970 where separation of the primary escapeway from the 
    belt and trolley haulage entries did not exist as of November 16, 1992. 
    For areas of mines developed after September 15, 1992, (those areas 
    covered by the existing rule) the provisions of paragraphs (f)(3) 
    through (f)(7) will be effective as of March 11, 1997. For other areas 
    covered by the rule, MSHA has provided for a 1 year phase in period to 
    allow mine operators time to effectively plan and implement the 
    necessary changes. The phase in period applies to areas of a primary 
    escapeway developed between March 30, 1970 and November 16, 1992, and 
    to areas of the primary escapeway developed prior to March 30, 1970 
    where separation of the belt and trolley haulage entries from the 
    primary escapeway existed prior to November 16, 1992.
        Paragraph (f)(3) prohibits certain equipment from being in the 
    primary escapeway. Paragraphs (f)(4) and (f)(5) deal with fire 
    protection for mobile equipment that is permitted in the primary 
    escapeway and paragraph (f)(6) addresses a specific circumstance when 
    mobile equipment may operate in a primary escapeway without a fire 
    suppression system. Paragraph (f)(7), a provision added to the proposed 
    language in response to comments, allows the use of designated 
    emergency vehicles or ambulances in the primary escapeway.
        One commenter suggested that the final rule should not provide an 
    exception for all areas where separation of the primary escapeway from 
    the belt and trolley haulage entry does not exist. The commenter 
    recognized, however, that Congress granted an exemption from separation 
    requirements for areas of the primary escapeway developed prior to 
    March 30, 1970, the effective date of the Act. The intent of the 
    proposal was to provide an exemption from the requirements of proposed 
    paragraphs (f)(3) through (f)(6) for these same areas. The commenter 
    points out that the proposal would have extended the exemption to other 
    areas of the primary escapeway where, for one reason or another, 
    separation did not exist on November 16, 1992, the effective date of 
    the existing rule. The final rule modifies the proposal to clarify that 
    the exemption only applies to those areas of the escapeway that were 
    developed prior to March 30, 1970 and where separation did not exist on 
    November 16, 1992.
        Another commenter correctly interpreted proposed paragraph (f)(2) 
    as extending the requirement that limits the types of equipment 
    permitted in primary escapeways to areas of the mine developed prior to 
    November 16, 1992. The commenter stated that the proposed regulation 
    would pose great cost to the industry with no appreciable safety 
    benefit derived. A review of the fire history relative to both 
    stationary and mobile equipment indicates that fires can and do occur 
    on this equipment. Mobile equipment by design is intended to provide 
    flexibility in movement and is capable of operating anywhere in the 
    mine. Although the accident reports do not specify whether the mobile 
    equipment that caught fire was in the primary escapeway when the fire 
    started, it is reasonable to conclude that at least some of these fires 
    did occur in the primary escapeway. MSHA continues to believe that 
    given the importance of the primary escapeway to the safety of miners, 
    the extension of the requirements for operation of equipment in the 
    primary escapeway is necessary and appropriate.
        Paragraph (f)(3) lists the equipment that is not permitted in the 
    primary escapeway. Under paragraph (f)(3)(i) of the final rule, 
    operating diesel equipment without an automatic fire suppression system 
    is prohibited in the primary escapeway unless it is attended, except as 
    provided in paragraphs (f)(6) and (f)(7). One commenter stated that 
    attended diesel equipment with a manual fire suppression system 
    presents no fire hazard. Another commenter suggested that unattended 
    diesel equipment should be prohibited. When diesel equipment is 
    operated in the primary escapeway and is properly attended and equipped 
    with a manual fire suppression system, the equipment operator can 
    immediately respond to a fire, and the safety afforded by the existing 
    standard is maintained. If the machine is shut off, however, attendance 
    is not necessary. When diesel equipment is to be operated unattended, 
    an automatic system is required to protect against fire.
        One commenter stated that ``attended'' should be interpreted to 
    mean that the operator is on or within sight of the vehicle. Another 
    commenter urged that the standard be clarified to require that the 
    operator be at the controls of the equipment. For the purposes of 
    Sec. 75.380(f), by ``attended'' MSHA means that the equipment operator 
    would be on the mobile 
    
    [[Page 9814]]
    equipment or immediately adjacent to the equipment and be capable of 
    activating the fire suppression system in the event of a fire.
        The existing standard permits equipment to be in the escapeway for 
    purposes of transporting miners and materials and for maintaining the 
    escapeway but does not expressly prohibit the haulage of coal in the 
    primary escapeway. As a matter of clarification, the final rule 
    specifically prohibits coal haulage in the primary escapeway unless 
    incidental to cleanup and maintenance of the escapeway. One commenter 
    supported the proposed prohibition of coal haulage noting that coal 
    haulage would provide a ready source of fuel to a machinery-initiated 
    fire. Several commenters expressed a concern that incidental coal 
    haulage associated with cleanup and maintenance of the primary 
    escapeway would be prohibited under the proposed standard. Cleanup and 
    maintenance of the primary escapeway must be permitted. Therefore, the 
    final rule modifies the proposal to permit mobile equipment to haul 
    coal if incidental to cleanup and maintenance of the primary escapeway.
        Paragraph (f)(3)(iii) prohibits compressors in the primary 
    escapeway except as provided in subparagraphs (f)(3)(iii) (A) through 
    (C). Subparagraph (A) allows compressors necessary to maintain the 
    escapeway in safe, travelable condition; (B) allows compressors that 
    are components of equipment such as locomotives and rock dusting 
    machines; and, (C) allows compressors of less than five horsepower due 
    to the limited fire hazard associated with their operation.
        One commenter described an incident involving a compressor in an 
    intake airway, which was located in a fireproof enclosure but was 
    improperly ventilated. According to the commenter, smoke and 
    contaminants spread throughout the intake entry and reached the 
    section, which was then evacuated. This illustrates the importance of 
    providing adequate protection from the possible spread of smoke and 
    contaminants associated with compressor fires or overheating.
        Paragraph (f)(3)(iv) of the final rule adds battery chargers to the 
    equipment included in the proposal that is permitted in the primary 
    escapeway provided they are located on or near a working section and 
    moved as the section advances or retreats. In all other respects, 
    paragraph (f)(3)(iv) of the final rule adopts the proposal. Under 
    paragraph (f)(3)(iv), underground transformer stations, battery 
    charging stations, substations, and rectifiers cannot be located in the 
    primary escapeway except: (A) where necessary to maintain the escapeway 
    in safe, travelable condition; and (B) battery chargers and rectifiers 
    and power centers with transformers that are either dry-type or contain 
    nonflammable liquid, provided they are located on or near a working 
    section and are moved as the section advances or retreats. The first 
    exception allows work to be performed in the primary escapeway to 
    assure its integrity. The second provides for the locations of the 
    described equipment at or near working sections if the equipment moves 
    with the section. Equipment at or near working sections will normally 
    be within a few crosscuts of the working face. In many cases, 
    particularly with battery chargers, there may be no practical 
    alternative to locating this equipment in the escapeway. In addition, 
    Sec. 75.340 provides additional protection when using underground 
    electrical equipment.
        Paragraph (f)(3)(v) of the final rule adopts the proposal and 
    prohibits water pumps from being in the primary escapeway except as 
    provided under paragraphs (f)(3)(v)(A) through (f)(3)(v)(F). The pumps 
    that are permitted in the primary escapeway are the same ones that are 
    excepted from the requirements of Sec. 75.340 due to the low potential 
    for fire associated with their operation. They include: water pumps 
    necessary to maintain the escapeway in safe, travelable condition; 
    submersible pumps; permissible pumps and associated permissible 
    switchgear; pumps located on or near a working section that are moved 
    as the section advances or retreats; pumps installed in anthracite 
    mines; and small portable pumps. While the existing rule refers to the 
    electrical equipment described in Sec. 75.340 (a) and (b)(1), the final 
    rule, like the proposal, lists the affected equipment for the 
    convenience of the reader. Like Sec. 75.340, paragraph (f)(3)(v) 
    applies to water pumps and emulsion pumps when they are located on or 
    near the working section and are moved as the section advances or 
    retreats. One commenter agreed that pumps may be necessary to maintain 
    and rehabilitate the primary escapeway but suggested that a time limit 
    be placed on the length of time the pump is allowed to remain in the 
    escapeway. MSHA believes that specific conditions at the mine will 
    govern the amount of time required for any necessary pumping. 
    Therefore, MSHA has not included the suggestion in the final rule since 
    the decision relative to time must be made on a case-by-case basis, as 
    appropriate.
        Paragraph (f)(4) of the final rule adopts MSHA's proposal with one 
    change. As proposed, paragraph (f)(4) would have required the use of 
    fire suppression systems on mobile equipment operated in the primary 
    escapeway, and would have allowed exceptions for continuous miners and 
    as provided in Sec. 75.380 (f)(5) and (f)(6). The final rule adds an 
    additional exception for emergency vehicles or ambulances as provided 
    in Sec. 75.380(f)(7). Unlike the existing standard, the final rule in 
    paragraph (f)(4) permits certain mobile equipment operated in the 
    primary escapeway to be protected with a manual fire suppression system 
    instead of an automatic system, provided it is attended by a person 
    trained in the use and operation of the fire suppression system. MSHA 
    believes that when a piece of equipment is operated in the primary 
    escapeway and is properly attended and equipped with a manual fire 
    suppression system, the equipment operator can immediately respond to 
    the situation, and the safety afforded by the existing standard is 
    maintained.
        One commenter stated that no electrical, battery or diesel 
    equipment, or other equipment such as compressors should be allowed in 
    the primary escapeway, except for the purpose of maintenance of the 
    escapeway, and that this equipment should have an appropriate fire 
    suppression system. Because travel in the escapeway in certain mining 
    systems is essential for safety given the design of the mining system 
    used, the recommendation of the commenter has not been adopted in the 
    final rule. Instead, the final rule provides that certain types of 
    mining equipment can be operated in the primary escapeway provided the 
    safety precautions set out in the standard are followed. One commenter 
    stated that the rule should only apply to mobile equipment which is 
    operated in the primary escapeway, since equipment not operating 
    presents little or no hazard. MSHA agrees and has incorporated this 
    clarification into the final rule.
        Commenters indicated that it is sometimes necessary to withdraw 
    face equipment, such as continuous miners, roof bolting machines and 
    shuttle cars, into the primary escapeway for a short distance beyond 
    the loading point. The equipment is sometimes parked and left there on 
    down shifts or between shifts. MSHA notes that, as clarified, the final 
    rule does not prohibit this practice. Because the equipment would be 
    attended when operated and is provided with manual fire suppression, 
    the 
    
    [[Page 9815]]
    equipment may be operated in the primary escapeway.
        Following promulgation of the existing rule, some persons construed 
    the requirement for an automatic fire suppression system to apply to 
    electric face equipment. As explained in the preamble to the proposal, 
    this was not the intent of MSHA. To clarify its intent, MSHA issued 
    Program Policy Letter No. P92-V-4 on November 16, 1992, addressing the 
    operation and location of equipment in primary escapeways. Under 
    existing regulations in Subpart L--Fire Protection, face equipment is 
    required to be protected by a manual fire suppression system. The final 
    rule recognizes and generally conforms with this requirement. Other 
    than for an exception to permit a situation such as the movement of 
    continuous mining machines between sections without a continuous water 
    supply, the final rule requires that when face machinery, equipped with 
    a manual fire suppression system, is operated in the primary escapeway, 
    it must be attended by a person trained in the proper function and use 
    of the fire suppression system. The continuous mining machine exception 
    recognizes that the fire suppression system for the continuous mining 
    machine often relies on a water supply that may be impracticable to 
    provide during equipment moves.
        The final rule requires in paragraph (f)(4) that with exceptions 
    for continuous mining machines and as provided in paragraphs (f)(5), 
    (f)(6), and (f)(7), each piece of mobile equipment operated in primary 
    escapeways shall: (1) be equipped with manually operated fire 
    suppression systems installed in compliance with Secs. 75.1107-3 
    through 75.1107-16 and be attended continuously; or (2) be equipped 
    with an automatic fire suppression system that is capable of both 
    automatic and manual activation and installed in compliance with 
    Secs. 75.1107-3 through 75.1107-16. Fire suppression systems which were 
    installed to meet the 1992 rule will continue to be accepted.
        Under paragraph (f)(5) of the final rule, personnel carriers and 
    small personnel conveyances designed and used solely for the 
    transportation of personnel and small hand tools can be operated in the 
    primary escapeway if either of the requirements under paragraphs (i) or 
    (ii) are met. This class of equipment would not include diesel-powered 
    pickup trucks, for example, which would be governed by paragraph 
    (f)(4). Paragraph (i) requires a multipurpose dry chemical type 
    automatic fire suppression system capable of both manual and automatic 
    activation. Paragraph (ii) provides an alternative for a class of 
    small, battery powered, golf cart type, equipment used for transport of 
    persons and small hand tools. In this case, fire extinguishers may be 
    used in lieu of a fire suppression system.
        Commenters questioned the need for automatic systems on the class 
    of equipment consisting of small, battery powered, golf cart type 
    equipment. One commenter suggested that a manual fire suppression 
    system should be accepted. After a review of the issue, MSHA has 
    concluded that some types of mobile equipment present a very limited 
    fire hazard. In the case of small, battery operated, golf cart type, 
    conveyances designed and used for the transport of personnel and small 
    hand tools, considering the limited hazard, a trained operator provided 
    with two 10 pound multi-purpose dry chemical fire extinguishers is 
    equivalent in protection to a fire suppression system. Accordingly, as 
    an alternative under paragraph (ii), small battery powered, golf cart 
    type, equipment may be operated in the primary escapeway if provided 
    with two 10 pound multi-purpose dry chemical fire extinguishers. Unlike 
    diesel powered equipment, the golf cart type of equipment is shut off 
    when not operating and, therefore, attendance is not an issue. The 10 
    pound units are standard size extinguishers and are appropriate for the 
    equipment involved.
        The system used in accordance with paragraph (i) must be suitable 
    for the intended application and listed or approved by a nationally 
    recognized independent testing laboratory. The language was proposed as 
    two paragraphs but has been combined in the final rule under paragraph 
    (i) and an alternative has been added as paragraph (ii). The types of 
    machinery which fall under paragraph (f)(5) are not required to meet 
    the additional requirements of Secs. 75.1107-3 through 75.1107-16. For 
    example, it would be impractical and would not enhance safety to apply 
    the minimum dry chemical poundage requirements of Sec. 75.1107-9 to 
    small equipment designed and used solely for personnel and small hand 
    tools.
        During informational meetings, it was suggested that the term ``dry 
    chemical'' would be more accurate and appropriate than the term ``dry 
    powder'' used in the existing standard. Like the proposal, the final 
    rule adopts this language. MSHA received no comments on this proposed 
    revision
        Paragraph (f)(6) of the final rule provides an exception to the 
    general requirement and allows mobile equipment not provided with a 
    fire suppression system to operate in the primary escapeway if no 
    persons are inby other than persons directly engaged in the use or 
    moving of the equipment. This provision of the final rule allows for 
    the necessary movement of face equipment, such as between sections.
        One commenter stated that the exemption provided in (f)(6) should 
    be expanded to allow equipment that does not have a fire suppression 
    system to be relocated provided monitoring equipment is utilized for 
    carbon monoxide or smoke and two-way communication is available to 
    notify appropriate persons. The final rule does not adopt this 
    suggestion. During moves, equipment is often laboring at maximum 
    capacity and there can be several machines operating simultaneously. 
    Under these conditions, equipment fires can develop quickly and the 
    products of combustion would be carried to inby workers by the 
    ventilating current. By permitting only workers who are directly 
    engaged in the operation or movement of the equipment, the final rule 
    prevents other workers from being exposed to the hazards of a fire on 
    the equipment being moved. Workers operating or engaged in moving the 
    equipment will be in a position to quickly identify the hazard and take 
    necessary action.
        Another commenter objected to the provision stating that fire 
    suppression should be required on all equipment in the primary 
    escapeway. This suggestion has not been adopted in the final rule. MSHA 
    does not agree that fire suppression is needed when no persons are inby 
    or downstream of the equipment being moved. MSHA has concluded that 
    either these machines should be equipped with fire suppression, or fire 
    extinguishers as in (f)(5)(ii), or no persons should be inby the 
    location where the equipment is being operated except those persons 
    directly engaged in the operation or movement of the equipment.
        Another commenter suggested that the wording of (f)(6) could be 
    read to allow miners to work on a longwall face while equipment not 
    equipped with fire suppression is operated anywhere in the primary 
    escapeway. This is not permitted by the standard. By including the 
    phrase, ``. . . except those persons directly engaged in using or 
    moving the equipment'', the persons affected are only those persons in 
    the immediate vicinity of the machine. With no persons working inby, 
    the use of machinery without a fire suppression system would not expose 
    persons to the hazard of toxic gases and fumes from a fire on the 
    equipment. The language 
    
    [[Page 9816]]
    also would not permit persons to operate mobile equipment without a 
    fire suppression system in the primary escapeway while miners are 
    downstream working on a longwall face. The controlling factor is 
    whether the persons inby are directly engaged in using or moving that 
    particular piece of equipment. If they are, and no one else is inby, 
    the equipment may be operated without a fire suppression system. For 
    example, when moving a longwall shield, no one would be permitted to be 
    inby the machine being used to move the shield if the machine is not 
    provided with a fire suppression system except those persons moving the 
    shield. This would include miners operating other pieces of equipment 
    to move other shields.
        Paragraph (f)(7) modifies the existing rule to include a new 
    exemption to the requirement that mobile equipment operated in primary 
    escapeways have a fire suppression system. Paragraph (f)(7) permits 
    mobile equipment designated and used only as emergency vehicles or 
    ambulances to operate in the primary escapeway without fire suppression 
    systems. It was suggested to MSHA that certain types of emergency 
    equipment, such as diesel powered ambulances, should be exempt from the 
    requirements for fire suppression systems. Comments were received 
    suggesting that ambulances should be exempt because space is extremely 
    limited on these vehicles and because they are used infrequently. MSHA 
    recognizes the potential benefit in the use of this type of equipment. 
    Another commenter objected, foreseeing potential abuses of the 
    exemption by mine operators who would designate equipment as ambulances 
    but use it as ordinary equipment. The final rule permits emergency 
    vehicles to be operated in the primary escapeway without fire 
    suppression systems only when this equipment is used for medical 
    emergencies.
        This existing rule requires in paragraph (i)(2) that mechanical 
    escape facilities be provided and maintained for, ``. . . each slope 
    that is part of a designated escapeway that is either inclined 18 
    degrees or more from the horizontal or is inclined 9 degrees or more 
    from the horizontal and is greater than 1,000 feet in length.'' During 
    informational meetings, MSHA became aware of a concern that existing 
    paragraph (i)(2) would permit slopes of significant length and 
    inclination to exist without any mechanical escape facilities. An 
    example would be a slope of 900 feet inclined less than 18 degrees from 
    the horizontal. It was suggested that such a slope could be 
    particularly difficult for passage of injured persons under cold and 
    icy conditions if mechanical escape facilities were not provided. In 
    light of this concern, MSHA proposed to require that mechanical escape 
    facilities be provided and maintained from the coal seam to the surface 
    for each slope that is part of a designated escapeway and is inclined 
    more than 9 degrees from the horizontal. The final rule adopts the 
    proposal.
        One commenter objected to proposed paragraph (i)(2) indicating that 
    facilities are unnecessary in low angle slopes which are of short 
    length. Other commenters believed that the 1992 standard was 
    appropriate. Another commenter indicated support for the proposal as a 
    way to enable persons to escape quickly in an emergency. This commenter 
    also noted that escape can be very difficult in icy winter conditions 
    in some slopes. After consideration of the comments received, MSHA 
    concludes that the proposal was appropriate and the final rule adopts 
    this aspect of the proposal.
        One commenter suggested that proposed paragraph (i)(2) could be 
    interpreted as requiring mechanical escape facilities for slopes that 
    occur naturally underground. It was not MSHA's intent to apply 
    paragraph (i)(2) to slopes other than from the coal seam to the 
    surface. The final rule clarifies this and requires that mechanical 
    escape facilities be provided for each slope from the coal seam to the 
    surface that is part of a designated escapeway and is inclined more 
    than 9 degrees from the horizontal.
        Like the proposal, the final rule in paragraph(d)(5) revises the 
    existing language dealing with the location of escapeways. It provides 
    that escapes shall be located to follow the most direct, safe and 
    practical route to the nearest mine opening suitable for the safe 
    evacuation of miners. A question arose during an informational meeting 
    as to whether MSHA intended that the existing rule eliminate the 
    requirement that escapeways be routed to the ``nearest mine opening.'' 
    It was not MSHA's intent to change this requirement from the previous 
    standard. The existing requirement that the escapeway follow the most 
    direct route to the surface would, in fact, require the route to go to 
    the nearest mine opening. However, to eliminate any confusion that may 
    exist, the final rule revises paragraph (d)(5) and adopts language 
    similar to that in previous regulation, Sec. 75.1704-2(a), that is, 
    that the escapeway must follow the most direct, safe and practical 
    route to the nearest mine opening suitable for the safe evacuation of 
    miners.
        One commenter stated that escapeways should not be permitted to 
    pass an opening to be routed to a more distant opening. Another 
    commenter stated that the nearest mine opening may not always be the 
    safest due to roof conditions or other factors. MSHA acknowledges that 
    the nearest mine opening may not always be the safest route to the 
    surface. A number of factors affect whether or not the safest, most 
    direct, practical route has been selected. These factors include roof 
    conditions, travel height, fan location, physical dimensions of the 
    mine opening, and similar considerations. For example, if bad roof 
    conditions are present along the shortest direct route and those roof 
    conditions are beyond reasonable control, then an alternate ``safe'' 
    route designated by the mine operator may be appropriate. However, the 
    presence of roof falls does not necessarily indicate that the 
    passageway would not be suitable for evacuation if it is reasonable to 
    rehabilitate the area. By way of another example, where coal seam 
    thickness varies to the extreme, the shortest route may be through 
    lower coal, making travel relatively slow and difficult. An alternate 
    route through a high passageway may permit easier travel. Such an 
    alternate route, although longer, may be more practical and therefore 
    may be more appropriate. Similarly, there can be instances where the 
    ``nearest mine opening'' may not be suitable for safe evacuation of 
    miners. For example, an old mine shaft may not be safe for travel 
    because of badly deteriorated conditions, such as a deteriorated shaft 
    lining or deteriorated timbers, even though the shaft is still suitable 
    for mine ventilation purposes.
        As with the existing standard, mine development projections do not 
    have to be altered to provide additional rooms, entries, or crosscuts 
    for the sole purpose of providing a passageway to the nearest mine 
    opening. However, the construction of ventilation controls such as 
    stoppings, overcasts and undercasts, or the installation of an escape 
    facility may be required to provide the most direct, safe and practical 
    route to the surface.
        One commenter suggested that MSHA should require an escapeway plan 
    to be approved by the MSHA district manager to assure the most direct 
    route to the surface. Existing standards require that escapeways be 
    shown on the ventilation map. In addition, as with other regulations, 
    inspectors assess whether escapeways follow the most direct, safe and 
    practical route to the surface during each regular inspection. 
    Accordingly, MSHA does not believe that an additional plan is 
    necessary. 
    
    [[Page 9817]]
    
        Existing paragraph (f) establishes the requirements for ventilation 
    of the primary escapeway and identifies which equipment can be operated 
    in the primary escapeway and the fire suppression requirements for this 
    equipment. The final rule, like the proposal, modifies paragraph (f) to 
    explicitly identify the equipment that is not permitted in the primary 
    escapeway and to specify the types of fire suppression systems that are 
    to be used and the conditions under which each is to be used on 
    equipment permitted in the primary escapeway. This is done by replacing 
    existing paragraphs (f)(1) and (f)(2) with paragraphs (f)(1) through 
    (f)(7) in the final.
        Existing paragraph (f)(1) requires that one escapeway that is 
    ventilated with intake air be designated as the primary escapeway and 
    prohibits certain equipment from being used in the primary escapeway in 
    areas developed after November 15, 1992. Further, paragraph (f)(1) 
    requires fire suppression systems on mobile equipment that is operated 
    in the primary escapeway. The final rule transfers the part of existing 
    paragraph (f)(1) that specifies the area of the primary escapeway 
    affected to paragraph (f)(2).
        The existing rule limited the installation or use of certain 
    equipment in areas of the primary escapeway developed after November 
    15, 1992. Paragraph (f)(2) of the final rule modifies the existing rule 
    for clarity and expands the application of certain requirements 
    contained in paragraphs (f)(3) through (f)(7) to the entire primary 
    escapeway except those areas of the primary escapeway developed prior 
    to March 30, 1970 where separation of the primary escapeway from the 
    belt and trolley haulage entries did not exist as of November 16, 1992. 
    For areas of mines developed after September 15, 1992, (those areas 
    covered by the existing rule) the provisions of paragraphs (f)(3) 
    through (f)(7) will be effective as of March 11, 1997. For other areas 
    covered by the rule, MSHA has provided for a 1 year phase in period to 
    allow mine operators time to effectively plan and implement the 
    necessary changes. The phase in period applies to areas of a primary 
    escapeway developed between March 30, 1970 and November 16, 1992, and 
    to areas of the primary escapeway developed prior to March 30, 1970 
    where separation of the belt and trolley haulage entries from the 
    primary escapeway existed prior to November 16, 1992.
        Paragraph (f)(3) prohibits certain equipment from the primary 
    escapeway. Paragraphs (f)(4) and (f)(5) deal with fire protection for 
    mobile equipment that is permitted in the primary escapeway and 
    paragraph (f)(6) addresses a specific circumstance when mobile 
    equipment may operate in a primary escapeway without a fire suppression 
    system. Paragraph (f)(7), a provision added to the proposed language in 
    response to comments, allows the use of designated emergency vehicles 
    or ambulances in the primary escapeway.
        One commenter suggested that the final rule should not provide an 
    exception for all areas where separation of the primary escapeway from 
    the belt and trolley haulage entry does not exist. The commenter 
    recognized, however, that Congress granted an exemption from separation 
    requirements for areas of the primary escapeway developed prior to 
    March 30, 1970, the effective date of the Act. The intent of the 
    proposal was to provide an exemption from the requirements of proposed 
    paragraphs (f)(3) through (f)(6) for these same areas. The commenter 
    points out that the proposal would have extended the exemption to other 
    areas of the primary escapeway where, for one reason or another, 
    separation did not exist on November 16, 1992, the effective date of 
    the existing rule. The final rule modifies the proposal to clarify that 
    the exemption only applies to those areas of the escapeway that were 
    developed prior to March 30, 1970 and where separation did not exist on 
    November 16, 1992.
        Another commenter correctly interpreted proposed paragraph (f)(2) 
    as extending the requirement that limits the types of equipment 
    permitted in primary escapeways to areas of the mine developed prior to 
    November 16, 1992. The commenter stated that the proposed regulation 
    would pose great cost to the industry with no appreciable safety 
    benefit derived. A review of the fire history relative to both 
    stationary and mobile equipment indicates that fires can and do occur 
    on this equipment. Mobile equipment by design is intended to provide 
    flexibility in movement and is capable of operating anywhere in the 
    mine. Although the accident reports do not specify whether the mobile 
    equipment that caught fire was in the primary escapeway when the fire 
    started, it is reasonable to conclude that at least some of these fires 
    did occur in the primary escapeway. MSHA continues to believe that 
    given the importance of the primary escapeway to the safety of miners, 
    the extension of the requirements for operation of equipment in the 
    primary escapeway is appropriate.
        Paragraph (f)(3) lists the equipment that is not permitted in the 
    primary escapeway. Under paragraph(f)(3)(i) of the final rule, 
    operating diesel equipment without an automatic fire suppression system 
    is prohibited in the primary escapeway unless it is attended, except as 
    provided in paragraphs (f)(6) and (f)(7). One commenter stated that 
    attended diesel equipment with a manual fire suppression system 
    presents no fire hazard. Another commenter suggested that unattended 
    diesel equipment should be prohibited. When diesel equipment is 
    operated in the primary escapeway and is properly attended and equipped 
    with a manual fire suppression system, the equipment operator can 
    immediately respond to a fire, and the safety afforded by the existing 
    standard is maintained. If the machine is shut off, however, attendance 
    is not necessary. When diesel equipment is to be operated unattended, 
    an automatic system is required to protect against fire.
        One commenter stated that ``attended'' should be interpreted to 
    mean that the operator is on or within sight of the vehicle. Another 
    commenter urged that the standard be clarified to require that the 
    operator be at the controls of the equipment. For the purposes of 
    Sec. 75.380(f), by ``attended'' MSHA means that the equipment operator 
    would be on the mobile equipment or immediately adjacent to the 
    equipment and be capable of activating the fire suppression system 
    immediately in the event of a fire.
        The existing standard permits equipment to be in the escapeway for 
    purposes of transporting miners and materials and for maintaining the 
    escapeway but does not expressly prohibit the haulage of coal in the 
    primary escapeway. As a matter of clarification, the final rule 
    specifically prohibits coal haulage in the primary escapeway unless 
    incidental to cleanup and maintenance of the escapeway. One commenter 
    supported the proposed prohibition of coal haulage noting that coal 
    haulage would provide a ready source of fuel to a machinery-initiated 
    fire. Several commenters expressed a concern that incidental coal 
    haulage associated with cleanup and maintenance of the primary 
    escapeway would be prohibited under the proposed standard. Cleanup and 
    maintenance of the primary escapeway must be permitted. Therefore, the 
    final rule modifies the proposal to permit mobile equipment to haul 
    coal if incidental to cleanup and maintenance of the primary escapeway.
        Paragraph (f)(3)(iii) prohibits compressors in the primary 
    escapeway except as provided in subparagraphs (f)(3)(iii) (A) through 
    (C). Subparagraph 
    
    [[Page 9818]]
    (A) allows compressors necessary to maintain the escapeway in safe, 
    travelable condition; (B) allows compressors that are components of 
    equipment such as locomotives and rock dusting machines; and, (C) 
    allows compressors of less than five horsepower due to the limited fire 
    hazard associated with their operation.
        One commenter described an incident involving a compressor in an 
    intake airway, which was located in a fireproof enclosure but was 
    improperly ventilated. According to the commenter, smoke and 
    contaminants spread throughout the intake entry and reached the 
    section, which was then evacuated. This illustrates the importance of 
    providing adequate protection from the possible spread of smoke and 
    contaminants associated with compressor fires or overheating.
        Paragraph (f)(3)(iv) of the final rule adds battery chargers to the 
    equipment included in the proposal that is permitted in the primary 
    escapeway provided it is located on or near a working section and is 
    moved as the section advances or retreats. In all other respects, 
    paragraph (f)(3)(iv) of the final rule adopts the proposal. Under 
    paragraph (f)(3)(iv), underground transformer stations, battery 
    charging stations, substations, and rectifiers cannot be located in the 
    primary escapeway except: (A) where necessary to maintain the escapeway 
    in safe, travelable condition; and (B) battery chargers and rectifiers 
    and power centers with transformers that are either dry-type or contain 
    nonflammable liquid, provided they are located on or near a working 
    section and are moved as the section advances or retreats. The first 
    exception allows work to be performed in the primary escapeway to 
    assure its integrity. The second provides for the locations of the 
    described equipment at or near working sections if the equipment moves 
    with the section. Equipment at or near working sections will normally 
    be within a few crosscuts of the working face. In many cases, 
    particularly with battery chargers, there may be no practical 
    alternative to locating this equipment in the escapeway. In addition, 
    Sec. 75.340 provides additional protection when using underground 
    electrical equipment.
        Paragraph (f)(3)(v) of the final rule adopts the proposal and 
    prohibits water pumps from being in the primary escapeway except as 
    provided under paragraphs (f)(3)(v)(A) through (f)(3)(v)(F). The pumps 
    that are permitted in the primary escapeway are the same ones that are 
    excepted from the requirements of Sec. 75.340 due to the low potential 
    for fire associated with their operation. They include: water pumps 
    necessary to maintain the escapeway in safe, travelable condition; 
    submersible pumps; permissible pumps and associated permissible 
    switchgear; pumps located on or near a working section that are moved 
    as the section advances or retreats; pumps installed in anthracite 
    mines; and small portable pumps. While the existing rule refers to the 
    electrical equipment described in Sec. 75.340 (a) and (b)(1), the final 
    rule, like the proposal, lists the affected equipment for the 
    convenience of the reader. Like Sec. 75.340, paragraph (f)(3)(v) 
    applies to water pumps and emulsion pumps when they are located on or 
    near the working section and are moved as the section advances or 
    retreats. One commenter agreed that pumps may be necessary to maintain 
    and rehabilitate the primary escapeway but suggested that a time limit 
    be placed on the length of time the pump is allowed to remain in the 
    escapeway. MSHA believes that specific conditions at the mine will 
    govern the amount of time required for any necessary pumping. 
    Therefore, MSHA has not included the suggestion in the final rule since 
    the decision relative to time must be made on a case-by-case basis, as 
    appropriate.
        Paragraph (f)(4) of the final rule adopts MSHA's proposal with one 
    change. As proposed, paragraph (f)(4) would have required the use of 
    fire suppression systems on mobile equipment operated in the primary 
    escapeway, and would have allowed exceptions for continuous miners and 
    as provided in Sec. 75.380(f)(5)and (f)(6). The final rule adds an 
    additional exception for emergency vehicles or ambulances as provided 
    in Sec. 75.380(f)(7). Unlike the existing standard, the final rule in 
    paragraph (f)(4) permits certain mobile equipment operated in the 
    primary escapeway to be protected with a manual fire suppression system 
    instead of an automatic system, provided it is continuously attended by 
    a person trained in the use and operation of the fire suppression 
    system. MSHA believes that when a piece of equipment is operated in the 
    primary escapeway and is properly attended and equipped with a manual 
    fire suppression system, the equipment operator can immediately respond 
    to the situation, and the safety afforded by the existing standard is 
    maintained.
        One commenter stated that no electrical, battery or diesel 
    equipment, or other equipment such as compressors should be allowed in 
    the primary escapeway, except for the purpose of maintenance of the 
    escapeway, and that this equipment should have an appropriate fire 
    suppression system. Because travel in the escapeway in certain mining 
    systems is essential for safety given the design of the mining system 
    used, the recommendation of the commenter has not been adopted in the 
    final rule. Instead, the final rule provides that certain types of 
    mining equipment can be operated in the primary escapeway provided the 
    safety precautions set out in the standard are followed. One commenter 
    stated that the rule should only apply to mobile equipment which is 
    operated in the primary escapeway, since equipment not operating 
    presents little or no hazard. MSHA agrees and has incorporated this 
    clarification into the final rule.
        Commenters indicated that it is sometimes necessary to withdraw 
    face equipment, such as continuous miners, roof bolting machines and 
    shuttle cars, into the primary escapeway for a short distance beyond 
    the loading point. The equipment is sometimes parked and left there on 
    down shifts or between shifts. MSHA notes that, as clarified, the final 
    rule does not prohibit this practice. Because the equipment would be 
    attended when operated and is provided with manual fire suppression, 
    the equipment may be operated in the primary escapeway.
        Following promulgation of the existing rule, some persons construed 
    the requirement for an automatic fire suppression system to apply to 
    electric face equipment. As explained in the preamble to the proposal, 
    this was not the intent of MSHA. To clarify its intent, MSHA issued 
    Program Policy Letter No. P92-V-4 on November 16, 1992, addressing the 
    operation and location of equipment in primary escapeways. Under 
    existing regulations in Subpart L--Fire Protection, face equipment is 
    required to be protected by a manual fire suppression system. The final 
    rule recognizes and generally conforms with this requirement. Other 
    than for an exception to permit a situation such as the movement of 
    continuous mining machines between sections without a continuous water 
    supply, the final rule requires that when face machinery, equipped with 
    a manual fire suppression system, is operated in the primary escapeway, 
    it must be attended by a person trained in the proper function and use 
    of the fire suppression system. The continuous mining machine exception 
    recognizes that the fire suppression system for the continuous mining 
    machine often relies on a water supply that may be impracticable to 
    provide during equipment moves. 
    
    [[Page 9819]]
    
        The final rule requires in paragraph (f)(4) that with exceptions 
    for continuous mining machines and as provided in paragraphs (f)(5), 
    (f)(6), and (f)(7), each piece of mobile equipment operated in primary 
    escapeways shall: (1) be equipped with manually operated fire 
    suppression systems installed in compliance with Secs. 75.1107-3 
    through 75.1107-16 and be attended continuously; or (2) be equipped 
    with an automatic fire suppression system that is capable of both 
    automatic and manual activation and installed in compliance with 
    Secs. 75.1107-3 through 75.1107-16.
        Under paragraph (f)(5) of the final rule, personnel carriers and 
    small personnel conveyances designed and used solely for the 
    transportation of personnel and small hand tools can be operated in the 
    primary escapeway if either of the requirements under paragraphs (i) or 
    (ii) are met. Paragraph (i) requires a multipurpose dry chemical type 
    automatic fire suppression system capable of both manual and automatic 
    activation. Paragraph (ii) provides an alternative for a class of 
    small, battery powered, golf cart type, equipment used for transport of 
    persons and small hand tools. In this case, fire extinguishers may be 
    used in lieu of a fire suppression system.
        Commenters questioned the need for automatic systems on the class 
    of equipment consisting of small, battery powered, golf cart type 
    equipment. One commenter suggested that a manual fire suppression 
    system should be accepted. After a review of the issue, MSHA has 
    concluded that some types of mobile equipment present a very limited 
    fire hazard. In the case of small, battery operated, golf cart type, 
    conveyances designed and used for the transport of personnel and small 
    hand tools, considering the limited hazard, a trained operator provided 
    with two 10 pound multi-purpose dry chemical fire extinguishers is 
    equivalent in protection to a fire suppression system. Accordingly, as 
    an alternative under paragraph (ii), small battery powered, golf cart 
    type, equipment may be operated in the primary escapeway if provided 
    with two 10 pound multi-purpose dry chemical fire extinguishers. Unlike 
    diesel powered equipment, the golf cart type of equipment is shut off 
    when not operating and, therefore, attendance is not an issue. The 10 
    pound units are standard size extinguishers and are appropriate for the 
    equipment involved.
        The system used in accordance with paragraph (i) must be suitable 
    for the intended application and listed or approved by a nationally 
    recognized independent testing laboratory. The language was proposed as 
    two paragraphs but has been combined in the final rule under paragraph 
    (i) and an alternative has been added as paragraph (ii). The types of 
    machinery which fall under paragraph (f)(5) are not required to meet 
    the additional requirements of Secs. 75.1107-3 through 75.1107-16. For 
    example, it would be impractical and would not enhance safety to apply 
    the minimum dry chemical poundage requirements of Sec. 75.1107-9 to 
    small equipment designed and used solely for personnel and small hand 
    tools.
        During informational meetings, it was suggested that the term ``dry 
    chemical'' would be more accurate and appropriate than the term ``dry 
    powder'' used in the existing standard. Like the proposal, the final 
    rule adopts this language. MSHA received no comments on this proposed 
    revision.
        Paragraph (f)(6) of the final rule provides an exception to the 
    general requirement and allows mobile equipment not provided with a 
    fire suppression system to operate in the primary escapeway if no 
    persons are inby other than persons directly engaged in the use or 
    moving of the equipment. This provision of the final rule allows for 
    the necessary movement of face equipment, such as between sections.
        One commenter stated that the exemption provided in (f)(6) should 
    be expanded to allow equipment that does not have a fire suppression 
    system to be relocated provided monitoring equipment is utilized for 
    carbon monoxide or smoke and two-way communication is available to 
    notify appropriate persons. The final rule does not adopt this 
    suggestion. During moves, equipment is often laboring at maximum 
    capacity and there can be several machines operating simultaneously. 
    Under these conditions, equipment fires can develop quickly and the 
    products of combustion would be carried to inby workers by the 
    ventilating current. By permitting only workers who are directly 
    engaged in the operation or movement of the equipment, the final rule 
    prevents other workers from being exposed to the hazards of a fire on 
    the equipment being moved. Workers operating or engaged in moving the 
    equipment will be in a position to quickly identify the hazard and take 
    necessary action.
        Another commenter objected to the provision stating that fire 
    suppression should be required on all equipment in the primary 
    escapeway. This suggestion has not been adopted in the final rule. MSHA 
    does not agree that fire suppression is needed when no persons are inby 
    or downstream of the equipment being moved. MSHA has concluded that 
    either these machines should be equipped with fire suppression, or fire 
    extinguishers as in (f)(5)(ii), or no persons should be inby the 
    location where the equipment is being operated except those persons 
    directly engaged in the operation or movement of the equipment.
        Another commenter suggested that the wording of (f)(6) could be 
    read to allow miners to work on a longwall face while equipment not 
    equipped with fire suppression is operated anywhere in the primary 
    escapeway. This is not permitted by the standard. By including the 
    phrase, ``* * * except those persons directly engaged in using or 
    moving the equipment'', the persons affected are only those persons in 
    the immediate vicinity of the machine. With no persons working inby, 
    the use of machinery without a fire suppression system would not expose 
    persons to the hazard of toxic gases and fumes from a fire on the 
    equipment. The language also would not permit persons to operate mobile 
    equipment without a fire suppression system in the primary escapeway 
    while miners are downstream working on a longwall face. The controlling 
    factor is whether the persons inby are directly engaged in using or 
    moving that particular piece of equipment. If they are, and no one else 
    is inby, the equipment may be operated without a fire suppression 
    system. For example, when moving a longwall shield, no one would be 
    permitted to be inby the machine being used to move the shield if the 
    machine is not provided with a fire suppression system except those 
    persons moving the shield. This would include miners operating other 
    pieces of equipment to move other shields.
        Paragraph (f)(7) modifies the existing rule to include a new 
    exemption to the requirement that mobile equipment operated in primary 
    escapeways have a fire suppression system. Paragraph (f)(7) permits 
    mobile equipment designated and used only as emergency vehicles or 
    ambulances to operate in the primary escapeway without fire suppression 
    systems. It was suggested to MSHA that certain types of emergency 
    equipment, such as diesel powered ambulances, should be exempt from the 
    requirements for fire suppression systems. Comments were received 
    suggesting that ambulances should be exempt because space is extremely 
    limited on these vehicles and because they are used infrequently. MSHA 
    recognizes the potential benefit in the use of this type of equipment. 
    Another commenter objected, foreseeing potential abuses of 
    
    [[Page 9820]]
    the exemption by mine operators who would designate equipment as 
    ambulances but use it as ordinary equipment. The final rule permits 
    emergency vehicles to be operated in the primary escapeway without fire 
    suppression systems only when this equipment is used only for medical 
    emergencies.
        This existing rule requires in paragraph (i)(2) that mechanical 
    escape facilities be provided and maintained for, ``. . . each slope 
    that is part of a designated escapeway that is either inclined 18 
    degrees or more from the horizontal or is inclined 9 degrees or more 
    from the horizontal and is greater than 1,000 feet in length.'' During 
    informational meetings, MSHA became aware of a concern that existing 
    paragraph (i)(2) would permit slopes of significant length and 
    inclination to exist without any mechanical escape facilities. An 
    example would be a slope of 900 feet inclined less than 18 degrees from 
    the horizontal. It was suggested that such a slope could be 
    particularly difficult for passage of injured persons under cold and 
    icy conditions if mechanical escape facilities were not provided. In 
    light of this concern, MSHA proposed to require that mechanical escape 
    facilities be provided and maintained from the coal seam to the surface 
    for each slope that is part of a designated escapeway and is inclined 
    more than 9 degrees from the horizontal. The final rule adopts the 
    proposal.
        One commenter objected to proposed paragraph (i)(2) indicating that 
    facilities are unnecessary in low angle slopes which are of short 
    length. Other commenters believed that the 1992 standard was 
    appropriate. Another commenter indicated support for the proposal as a 
    way to enable persons to escape quickly in an emergency. This commenter 
    also noted that escape can be very difficult in icy winter conditions 
    in some slopes. After consideration of the comments received, MSHA 
    concludes that the proposal was appropriate and the final rule adopts 
    this aspect of the proposal.
        One commenter suggested that proposed paragraph (i)(2) could be 
    interpreted as requiring mechanical escape facilities for slopes that 
    occur naturally underground. It was not MSHA's intent to apply 
    paragraph (i)(2) to slopes other than from the coal seam to the 
    surface. The final rule clarifies this and requires that mechanical 
    escape facilities be provided for each slope from the coal seam to the 
    surface that is part of a designated escapeway and is inclined more 
    than 9 degrees from the horizontal.
    Section 75.382  Mechanical Escape Facilities
        Because an escapeway route can sometimes be very long, the most 
    safe, direct and practical route to the surface can sometimes involve 
    the use of a mechanical escape device such as an automatic elevator or 
    similar, but less sophisticated, device. Section 75.382 contains the 
    requirements for mechanical escape facilities installed in escapeways 
    under Sec. 75.380 and Sec. 75.381. The final rule contains a new 
    requirement for certification of escape facility examinations, proposed 
    as paragraph (g). The final rule does not retain the other proposed 
    changes, paragraphs (h) and (i), that would have added recordkeeping 
    and countersigning requirements.
        Under paragraph (g) of the final rule, the designated examiner 
    certifies by date, time, and initials that the mechanical escape 
    facilities examination required by paragraph Sec. 75.382(c) was 
    performed. The certification must be located at or near the facility 
    examined. Certification has long been an accepted practice in the 
    mining industry for assuring that a required examination has been 
    completed. One commenter agreed that certification is necessary and 
    supported the revision. The commenter indicated that the facilities are 
    often designated as escapeways and therefore there should be some 
    assurance that the facilities have been examined and are ready for use. 
    Also, in the case of mechanical escape facilities, if certification is 
    not provided, precious time could be lost as the escape facility is 
    tested prior to use to determine if it is functional and safe.
        Under the proposed paragraphs (h) and (i), a record would have had 
    to be made of the examination of the escape facility performed in 
    accordance with Sec. 75.382 (c). The results of the examination would 
    be included in a record, including any deficiency found along with the 
    corrective actions taken to correct the condition. One commenter 
    supported the revision requiring records of deficiencies found during 
    examinations as well as a record of corrective actions. Other 
    commenters objected to additional records, noting that they would not 
    enhance safety. After review of the comments, MSHA has concluded that 
    certification will achieve the intended objective of assuring the 
    safety of mechanical escape. Accordingly, the recordkeeping 
    requirements proposed as paragraphs (h) and (i) are omitted from the 
    final rule.
        One commenter stated that many companies utilize mobile escape 
    facilities to cover more than one mine if the mines are located in 
    close proximity. The commenter believed that such an arrangement was 
    not considered in the countersigning provisions of the proposal and 
    stated, ``The effort required to go to each mine every week and track 
    down the mine foreman would be burdensome and unnecessary.'' Paragraph 
    (c) of the existing rule requires a weekly examination and a weekly 
    test in which the hoist must be run through one complete cycle of 
    operation to determine that it is operating properly. The final rule 
    requires certification to be completed by the examiner. As indicated 
    above, MSHA has concluded that certification will achieve the intended 
    objective of assuring that the examinations have been conducted.
        Additional comments were received recommending further 
    modifications and additions to Sec. 75.382. For example, a commenter 
    recommended 2-way communication capability, with supplies and a holding 
    area at the escape facility. These types of comments related to issues 
    outside the scope of the rulemaking and were not addressed. Another 
    commenter would have MSHA reinstate language from an earlier rule, 
    alleging a reduction in protection. MSHA does not believe that there is 
    a reduction in protection. Also, the final rule did not propose to 
    change the existing requirement that the commenter claimed reduced 
    protection, i.e., that a person trained to operate the mechanical 
    escape facility always shall be available. MSHA notes that this issue 
    is outside the scope of the rulemaking.
    Section 75.383  Escapeway Maps and Drills
        When a fire, explosion or other emergency necessitates an immediate 
    evacuation of a mine the designated route for miners to leave the mine 
    is the escapeway. During a mine fire, passageways, even those 
    designated as escapeways, can become smoke filled and the ability to 
    see can be drastically reduced. Therefore, it is vitally important that 
    miners know the route of travel through the escapeway. Section 75.383 
    provides for the posting of escapeway maps so that they are available 
    for miners to study and use during an emergency, if necessary. Section 
    75.383 also provides for miners to be trained in the escape route 
    through escapeway drills. Escapeway drills in mines are similar to fire 
    drills in schools and high rise buildings.
        Existing paragraphs (a) and (b)(1) of Sec. 75.383 deal with the 
    escapeway map and drill requirements in areas where mechanized mining 
    equipment is being 
    
    [[Page 9821]]
    installed or removed. Based on comments received, the final rule 
    contains 2 revisions to the proposal. The first allows the mine map to 
    be readily accessible as an alternative to posting. The second requires 
    that miners who are underground when any change is made to the 
    escapeway map be immediately notified of the change. These revisions to 
    the proposal are discussed below.
        One commenter supported the requirements of (a) and (b)(1) noting 
    the hazards and activities where mechanized mining equipment is being 
    installed or removed. Another commenter stated that the requirement 
    that the map be ``posted'' is impractical in some mines. The commenter 
    stated that the rule should simply require that the map be maintained 
    on the section to allow the map to be maintained in a map tube, or be 
    covered. The commenter also indicated that a map tube could aid miners 
    in a rapid escape since the map and tube could easily be taken with the 
    miners during the escape. MSHA agrees that the maintenance of a posted 
    map could be difficult in some conditions such as in wet or very low 
    height mines. Accordingly, the final rule provides an option wherein 
    the map may be either posted or be maintained in a location readily 
    accessible to all miners. In specifying ``readily accessible'' MSHA 
    intends that all miners be made aware of the map location and have 
    access to review the map at any time. As an example, a map secured in a 
    locked tool chest would not be acceptable.
        One commenter objected to paragraph (a) in two respects. First, 
    according to the commenter, the standard does not require maps to show 
    the revised escapeway routes until the end of the shift on which the 
    changes are made. The commenter believes that changes are projected in 
    advance and therefore the maps should be updated immediately. Second, 
    the commenter indicated that the requirement that miners must be 
    informed of the changes before entering the mine does not address 
    affected miners already underground. Many changes within escapeways are 
    not known or planned well in advance. Often, such revisions are in 
    response to changing conditions underground. MSHA does not believe that 
    allowing a portion of one shift is an excessive amount of time to 
    update the maps. MSHA does agree, however, that changes to the 
    escapeways should be immediately brought to the attention of all miners 
    who are underground at the time of a change. Accordingly, the final 
    rule specifies that all affected miners already underground must be 
    immediately notified of the change. This will assure that all affected 
    miners are aware of the change from the time the change is implemented.
        While agreeing that each miner's familiarity with escapeways is 
    important, one commenter stated that requiring travel by foot in the 
    escapeways could cause undue physical stress to some miners in low or 
    steeply pitching seams. The commenter continued that the desired result 
    could be obtained by requiring full participation in drills where 
    transportation is provided and full participation in drills where 
    transportation is not provided, unless that escapeway is equipped with 
    a continuous, directional life line. MSHA notes that the standard does 
    not require travel on foot. Transportation may be used for escapeway 
    drills provided that the purpose of the standard can be achieved. That 
    purpose is to assure that miners are familiar with the escapeway routes 
    and, as specified in (b)(4), before or during practice escapeway 
    drills, miners shall be informed of the locations of fire doors, check 
    curtains, changes in the routes of travel, and plans for diverting 
    smoke from escapeways. Traveling an escapeway in a completely enclosed 
    mantrip, such that the route could not be observed, would not meet the 
    requirement. As to the concept of exempting drills in the alternate 
    escapeway where mechanized transportation is unavailable if a 
    directional lifeline exists, MSHA believes that certain minimum 
    specifications for lifelines would be needed before such a compliance 
    alternative could be considered. This would expand the scope of this 
    rulemaking beyond the proposal.
        One commenter suggested an expansion of 75.383 to require: 
    directional life lines in both escapeways; communications in both 
    escapeways; numbering of all stoppings along escapeways; additional 
    SCSR caches; hard hat stickers depicting escapeways and SCSR donning 
    procedures; and other measures. While many of the suggestions may have 
    merit, they are outside the scope of this rulemaking.
        In the proposal, MSHA solicited comments on a concept to allow 
    individual miners to opt out of escapeway drills for health reasons. 
    One commenter indicated that a number of additional requirements would 
    be needed to assure that any miners opting out would still remain 
    familiar with the escapeways. After considering the comments received, 
    MSHA has not included an option for miners to opt out of the escapeway 
    drills. As one commenter pointed out, it is essential that each miner 
    be familiar with the escapeways. MSHA concludes that a number of 
    accommodations can be made to provide assistance to any miner 
    experiencing difficulty during drills. As discussed above, mobile 
    equipment may be used provided that the conveyance is not so enclosed 
    that miners cannot observe the route. Operators can allow additional 
    time for miners who may encounter difficulty. Also, assistance can be 
    provided by other miners, particularly in difficult areas such as 
    unusually steep grades. Such assistance would likely also be needed in 
    an actual emergency and therefore the drills would be particularly 
    instructive to all the miners participating in the drills.
        MSHA believes that for areas where mechanized mining equipment is 
    being installed or removed, providing escapeways and posting maps 
    identifying these escapeways and conducting the drills specified in the 
    standard are essential to maintain safety. These requirements help to 
    assure that miners are familiar with escape routes so that should 
    urgent escape become necessary, they can reach the surface as quickly 
    as possible.
    Section 75.384  Longwall and Shortwall Travelways
        Modern mining methods include removing large blocks of coal in one 
    continuous operation along a wall which can be several hundred feet 
    long. This method is known as longwall or shortwall mining. To avoid 
    trapping miners in the face area without a means of escape in the event 
    of an emergency, there is a need to have a travelway on the side of the 
    block of coal opposite the escapeways. Section 75.384 addresses the 
    requirements for a travelway on the tailgate side of a longwall or 
    shortwall, the location and marking of the travelway, and procedures to 
    follow during a blockage of the travelway.
        MSHA proposed no changes to the existing rule. Likewise, the final 
    rule makes no changes to the existing rule. The preamble to the 
    proposal explained that MSHA had received comment suggesting that the 
    existing rule be modified to provide for additional involvement by 
    miners when a roof fall or other blockage occurs that prevents travel 
    in the tailgate travelway. MSHA believes that the existing procedures 
    and regulations appropriately address the hazards and provide a 
    sufficient opportunity for input and involvement for all interested 
    parties. The preamble to the proposal contains a discussion of the 
    existing procedures and regulations.
        One commenter recommended several additions to existing Sec. 75.384 
    while 
    
    [[Page 9822]]
    agreeing that maintenance of a tailgate travelway is essential. The 
    recommendations included requiring the tailgate travelway to be 
    ventilated by intake air. The commenter noted that several mines 
    presently ventilate in this manner, providing intake air splits at both 
    headgate and tailgate. While this system has certain advantages, it is 
    not feasible or practical in all cases.
    Section 75.388  Boreholes in Advance of Mining.
        Areas of a mine, or of an adjacent mine, can be located in close 
    proximity to an advancing working place but can be inaccessible for a 
    variety of reasons. These inaccessible areas of a mine can present 
    hazards when mining proceeds inadvertently or improperly into these 
    areas. Inaccessible areas may contain potentially dangerous 
    accumulations of gases or water, which could result in explosions or 
    inundations. To protect against these hazards, Sec. 75.388 requires 
    operators to drill boreholes into the coal before they extract it. In 
    this manner, the operator can determine whether mining, if continued, 
    will penetrate an area where unknown hazards may be present. Boreholes 
    are not required when the area toward which mining is advancing is 
    accessible and is properly examined.
        The final rule revises requirements for the drilling of boreholes 
    in advance of mining. It requires boreholes to be drilled in both ribs 
    of advancing working places unless an alternative drilling plan is 
    approved by the district manager in accordance with existing paragraph 
    (g) of this section. Existing paragraph (c) requires that boreholes be 
    drilled in at least one rib of advancing working places described in 
    Sec. 75.388 (a). Although MSHA did not intend any change in 
    promulgating the existing language, comments indicated that some 
    confusion existed. To address this issue, MSHA proposed to revise the 
    existing standard and adopt language similar to the regulation which 
    was in effect prior to 1992. The proposed revisions to Sec. 75.388 (c) 
    would have required bore holes to be drilled in one or both ribs of 
    advancing working places described in Sec. 75.388(a), `` . . . as may 
    be necessary for adequate protection of miners in such working 
    places.''
        Several comments were received in response to the proposal. One 
    commenter indicated that the proposed revision was unnecessary since 
    the 1992 standard adequately indicated that more than one rib may need 
    to be drilled. Another commenter stated that drilling one rib is always 
    adequate since required drilling in adjacent places will assure that 
    the entire area is explored by drilling. MSHA's experience is that 
    working places are seldom developed at the same rate and some may lag 
    by significant distances. In addition, entry or room centers are 
    ordinarily in excess of the 20 foot drill hole depth specified in the 
    standard. Thus, coverage over the entire width of the advancing section 
    is not always provided as suggested by the commenter. Another example 
    would be where an advance heading approaches an inaccurately mapped 
    abandoned mine such that the unknown workings are approached near the 
    undrilled ribline. An inundation could occur at the undrilled ribline 
    as the working place advanced. To address these hazards, the final rule 
    requires drilling of both ribs. If the workings were not discovered 
    through drilling, multiple fatalities could result from inundations of 
    water, methane, or oxygen deficient atmosphere (black damp). Accidents 
    similar to this scenario have occurred and resulted in inundations of 
    water, methane, or irrespirable atmospheres.
        One commenter noted that 38 inundations of gases or water occurred 
    between 1990 and 1994. MSHA notes that this number represents only 
    those accidental cut-throughs which resulted in inundations. It should 
    be noted that numerous additional accidental cut-throughs have occurred 
    which did not result in inundations. Each of these additional 
    accidental cut-throughs demonstrates the potential for a serious or 
    fatal accident. The commenter stated that the number of inundations and 
    the potential for multiple fatalities warrant a revision to the 
    standard to require both ribs to be drilled. Similar comments and 
    examples were heard during the public hearings. MSHA agrees.
        MSHA concludes that in general, both ribs should be drilled; 
    however, under some circumstances drilling of both ribs may be 
    unnecessary. Moreover, MSHA recognizes that there are circumstances 
    where it would be unnecessary to drill both ribs at all times. Thus, 
    the final rule requires that both ribs be drilled unless the district 
    manager grants approval for an alternative drilling pattern under 
    existing paragraph (g). Under existing paragraph (g), an alternative 
    drilling pattern may be approved which may not require drilling of both 
    ribs. As with other plans which are subject to approval, requests for 
    alternative drilling patterns will be reviewed on a case by case basis. 
    After considering all comments received discussing this issue, MSHA has 
    concluded that the hazard of an inundation is properly addressed by the 
    final rule which retains sufficient flexibility for a site specific 
    drilling pattern if the district manager can be satisfied that the 
    alternative is suitable to the particular circumstances.
        Another comment suggested that the minimum distances which trigger 
    drilling as specified in Sec. 75.388 (a)(1), (a)(2), and (a)(3) be 
    revised to 100, 500, and 500 feet, respectively. In support of the 
    suggestion, the commenter noted factors such as inaccurate old mine 
    maps, unmapped mining over-boundary or outside the legal limits, lost 
    maps or unknown mines, and less than diligent research by some 
    operators. The minimum drilling distances in paragraph (a) were not 
    proposed for revision and the final rule does not address them. 
    However, it is important to note that the distances specified are the 
    minimum at which drilling must begin if there is reasonable confidence 
    in the position of the old workings. The distances specified provide a 
    safety factor to account for slight mining overruns, mapping errors, 
    small deliberate omissions, and similar factors in cases where the 
    position of the old workings are known with reasonable certainty. In 
    cases where old workings are known to exist but the position is unknown 
    or known with little confidence, drilling would be necessary in excess 
    of the minimum distances specified in (a) to assure compliance with the 
    standard.
    Section 75.389  Mining into Inaccessible Areas
        While Sec. 75.388 addresses the need to identify inaccessible areas 
    to avoid accidentally drilling into an area containing a possible 
    hazardous environment, Sec. 75.389 establishes procedures for drilling 
    into an inaccessible area that has been identified. Section 75.389 
    requires a separate plan be developed and approved for drilling into 
    inaccessible areas. Paragraph (c) of the final rule clarifies that the 
    requirements of Sec. 75.389(c)(1), (c)(2) and (c)(3) do not apply to 
    routine mining-through operations that are part of a retreat section 
    ventilation system approved in accordance with Sec. 75.371(f) and (x). 
    The final rule retains the proposed language.
        The preamble to the proposal pointed out that, based on comments 
    received during informational meetings and other discussions, differing 
    interpretations of the application of existing Sec. 75.389 existed. 
    Some persons were interpreting paragraph (c) as requiring, for example, 
    the mine to be evacuated during the break-through of a pillar split in 
    a retreating section. However, paragraphs (a) through (c) of 
    Sec. 75.389 were intended to apply during mining-through operations in 
    areas subject to Sec. 75.388 
    
    [[Page 9823]]
    where hazards and potential hazards may be unknown. The final rule 
    revises existing Sec. 75.389(c) by adding an exception for routine 
    mining-through operations that are a part of a retreat mining system 
    approved in the mine ventilation plan. In some circumstances, the 
    mining through occurs during routine mining into an area which is 
    covered by an approved mine ventilation plan. In this case, the 
    potential hazards have already been addressed in the mine ventilation 
    plan. Requiring the operator to submit duplicate plans would not result 
    in any safety benefit; therefore, the level of safety provided by the 
    existing standard is maintained.
    
    Petitions for Modification
    
        Operators with petitions for modification that involve the 
    standards revised in this rulemaking need to determine the status of 
    those petitions before the effective date of the rule. If there are 
    sections of this rule that are renumbered but remain substantively 
    unchanged from the existing standards, operators with modifications 
    granted for these standards need not reapply. However, operators with 
    petitions for modifications granted for standards that have been 
    revised must comply with the new rule on its effective date. New 
    petitions for modification of the final rule may be submitted under 30 
    CFR part 44. If Agency assistance is needed, questions should be 
    directed to the appropriate MSHA district office.
    
    Derivation Table
    
        The following derivation table lists the number of each final 
    standard and the number of the existing standard from which it is 
    derived.
    
    ------------------------------------------------------------------------
             New section                          Old section               
    ------------------------------------------------------------------------
    75.301.......................  Partly new, 75.301.                      
    75.310(a)(3).................  Partly new, 75.310(a)(3).                
    75.310(a)(4).................  Partly new, 75.310(a)(4).                
    75.310(c)....................  Partly new, 75.310(c).                   
    75.310(c)(1).................  Partly new, 75.310(c).                   
    75.310(c)(2).................  75.310(c).                               
    75.310(c)(3).................  New.                                     
    75.310(c)(4).................  Partly new, 75.310(c).                   
    75.310(c)(4)(i)..............  75.310(c)(1).                            
    75.310(c)(4)(ii).............  75.310(c)(2).                            
    75.310(c)(5).................  New.                                     
    75.311(d)....................  Partly new, 75.311(d).                   
    75.312(a)....................  Partly new, 75.312(a).                   
    75.312(b)(1).................  Partly new, 75.312(b)(1).                
    75.312(b)(1)(i)..............  New.                                     
    75.312(b)(1)(ii).............  75.312(b)(1) through(b)(1)(ii).          
    75.312(c)....................  Partly new, 75.312(c).                   
    75.312(d)....................  Partly new, 75.312(d).                   
    75.312(f)(1).................  75.312(f).                               
    75.312(f)(2).................  New.                                     
    75.312(g)(1).................  Partly new, 75.312(g)(1).                
    75.312(g)(2).................  New.                                     
    75.312(g)(3).................  Partly new, 75.312(g)(3).                
    75.312(h)....................  Partly new, 75.312(h).                   
    75.313(a)(1).................  75.313(a)(1).                            
    75.313(a)(2).................  75.313(a)(2).                            
    75.313(a)(3).................  75.313(a)(3).                            
    75.313(b)....................  75.313(b).                               
    75.313(c)(1).................  75.313(c)(1).                            
    75.313(c)(2).................  Partly new, 75.313(c)(2).                
    75.313(c)(3).................  Partly new, 75.313(c)(3).                
    75.313(d)(1)(i)..............  Partly new, 75.313(d)(1)(i).             
    75.313(d)(1)(ii).............  Partly new, 75.313(d)(1)(ii).            
    75.313(d)(2).................  Partly new, 75.313(d)(2).                
    75.320(e)....................  New.                                     
    75.321(a)(1).................  Partly new, 75.321(a).                   
    75.321(a)(2).................  Partly new, 75.321(a).                   
    75.323(b)(1).................  75.323(b)(1).                            
    75.323(b)(1)(i)..............  75.323(b)(1)(i).                         
    75.323(b)(1)(ii).............  Partly new, 75.323(b)(1)(ii).            
    75.323(b)(1)(iii)............  75.323(b)(1)(iii).                       
    75.323(b)(2).................  75.323(b)(2).                            
    75.323(b)(2)(i)..............  75.323(b)(2)(i).                         
    75.323(b)(2)(ii).............  75.323(b)(2)(ii).                        
    75.323(c)(1).................  Partly new, 75.323(c)(1).                
    75.323(d)(2)(i)..............  Partly new, 75.323(d)(2)(i).             
    75.325(d)....................  Partly new, 75.325(d).                   
    75.330(c)....................  New.                                     
    75.332(a)(1).................  75.332(a)(1).                            
    75.333(a)....................  Partly new, 75.333(a).                   
    75.333(b)(1).................  Partly new, 75.333(b)(1).                
    75.333(b)(3).................  Partly new, 75.333(b)(3).                
    75.333(b)(4).................  Partly new, 75.333(b)(4).                
    75.333(e)(1)(i)..............  Partly new, 75.333(e)(1).                
    75.333(e)(1)(ii).............  Partly new, 75.333(e)(2).                
    75.333(h)....................  75.333(e)(1).                            
    75.334(e)....................  Partly new, 75.334(e).                   
    
    [[Page 9824]]
                                                                            
    75.334(f)(3).................  Partly new, 75.334(f)(3).                
    75.340(a)....................  Partly new, 75.340(a).                   
    75.342(a)(4).................  Partly new, 75.342(a)(4).                
    75.342(a)(4)(i)..............  New.                                     
    75.342(a)(4)(ii).............  New.                                     
    75.342(a)(4)(iii)............  New.                                     
    75.344(a)....................  Partly new, 75.344(a).                   
    75.344(a)(1).................  Partly new, 75.344(b)(1).                
    75.344(a)(2).................  Partly new, 75.344(a)(1).                
    75.344(a)(2)(i)..............  75.344(b)(2)(i).                         
    75.344(a)(2)(ii).............  75.344(b)(2)(ii).                        
    75.344(b)....................  Partly new, 75.344(a)(2).                
    75.344(e)....................  New.                                     
    75.360(a)(1).................  Partly new, 75.360(a)(1).                
    75.360(a)(2).................  New.                                     
    75.360(b)....................  75.360(b).                               
    75.360(b)(1).................  Partly new, 75.360(b)(1).                
    75.360(b)(3).................  Partly new, 75.360(b)(3).                
    75.360(b)(4).................  Partly new, 75.360(b)(4).                
    75.360(b)(6)(i)..............  Partly new, 75.360(b)(6).                
    75.360(b)(6)(ii).............  Partly new, 75.360(b)(6).                
    75.360(b)(8).................  New.                                     
    75.360(b)(9).................  New.                                     
    75.360(b)(10)................  New.                                     
    75.360(e)....................  75.360(f).                               
    75.360(f)....................  Partly new, 75.360(g).                   
    75.360(g)....................  Partly new, 75.360(h).                   
    75.362(a)(1).................  Partly new, 75.362(a)(1).                
    75.362(a)(2).................  New.                                     
    75.362(c)(1).................  Partly new, 75.362(c)(1).                
    75.362(c)(2).................  75.362(c)(2).                            
    75.362(d)(1)(i)..............  New.                                     
    75.362(d)(1)(iii)............  Partly new, 75.362(d)(1)(ii).            
    75.362(d)(2).................  Partly new, 75.362(d)(2).                
    75.362(g)(1).................  New.                                     
    75.362(g)(2).................  New.                                     
    75.363.......................  Partly new, 75.313, 75.361, 75.362.      
    75.364(a)(1).................  Partly new, 75.364(a)(1).                
    75.364(a)(2)(i)..............  Partly new, 75.364(a)(2)(i).             
    75.364(a)(2)(ii).............  Partly new, 75.364(a)(2)(ii).            
    75.364(a)(2)(iii)............  Partly new, 75.364(a)(2)(iii).           
    75.364(a)(2)(iv).............  Partly new, 75.364(a)(2)(iii).           
    75.364(h)....................  Partly new, 75.364(h).                   
    75.364(i)....................  Partly new, 75.364(i).                   
    75.370(a)(3).................  Partly new, 75.370(a)(3).                
    75.370(a)(3)(i)..............  New.                                     
    75.370(a)(3)(ii).............  75.370(a)(3).                            
    75.370(a)(3)(iii)............  Partly new, 75.370(a)(3).                
    75.370(b)....................  New.                                     
    75.370(c)(1).................  Partly new, 75.370(b)(1).                
    75.370(c)(2).................  75.370(b)(2).                            
    75.370(f)....................  Partly new, 75.370(e).                   
    75.370(f)(1).................  New.                                     
    75.370(f)(2).................  Partly new, 75.370(e).                   
    75.370(f)(3).................  Partly new, 75.370(e).                   
    75.371(r)....................  Partly new, 75.371(r).                   
    75.371(s)....................  Partly new, 75.371(s).                   
    75.371(z)....................  Partly new, 75.371(z).                   
    75.371(bb)...................  Partly new, 75.371(bb).                  
    75.371(cc)...................  Partly new, 75.371(cc).                  
    75.372(b)(3).................  Partly new, 75.372(b)(3).                
    75.372(b)(19)................  New.                                     
    75.372(b)(20)................  New.                                     
    75.380(b)(1).................  75.380(b)(1).                            
    75.380(b)(2).................  75.380(b)(2).                            
    75.380(d)(3).................  Partly new, 75.380(d)(3).                
    75.380(d)(4)(ii).............  Partly new, 75.380(d)(4)(ii).            
    75.380(d)(4)(iii)............  New.                                     
    75.380(d)(4)(iv).............  New.                                     
    75.380(d)(5).................  Partly new, 75.380(d)(5).                
    75.380(f)....................  Partly new, 75.380(f)(1).                
    75.380(f)(1).................  Partly new, 75.380(f)(1).                
    75.380(f)(2).................  Partly new, 75.380(f)(1).                
    
    [[Page 9825]]
                                                                            
    75.380(f)(3).................  Partly new, 75.380(f)(1).                
    75.380(f)(4).................  Partly new, 75.380(f)(2).                
    75.380(f)(5).................  Partly new, 75.380(f)(2).                
    75.380(f)(6).................  New.                                     
    75.380(f)(7).................  New.                                     
    75.380(i)(2).................  Partly new, 75.380(i)(2).                
    75.382(g)....................  New.                                     
    75.383(a)....................  Partly new, 75.383(a).                   
    75.383(b)(1).................  75.383(b)(1).                            
    75.388(c)....................  Partly new, 75.388(c).                   
    75.389(c)....................  New.                                     
    75.389(c)(1).................  75.389(c)(1).                            
    ------------------------------------------------------------------------
    
    
    
    Redesignation Table
    
        The following redesignation table lists the section number of the 
    existing standard and the section number of the final standard which 
    contain revised provisions derived from the corresponding existing 
    section.
    
    ----------------------------------------------------------------------------------------------------------------
                       Old section                                              New section                         
    ----------------------------------------------------------------------------------------------------------------
    75.310(a)(3)....................................  75.310(a)(3).                                                 
    75.310(a)(4)....................................  75.310(a)(4).                                                 
    75.310(c).......................................  75.310(c).                                                    
    75.310(c).......................................  75.310(c)(1).                                                 
    75.310(c).......................................  75.310(c)(2).                                                 
    75.310(c).......................................  75.310(c)(4).                                                 
    75.310(c)(1)....................................  75.310(c)(4)(i).                                              
    75.310(c)(2)....................................  75.310(c)(4)(ii).                                             
    75.311(d).......................................  75.311(d).                                                    
    75.312(a).......................................  75.312(a).                                                    
    75.312(b)(1)....................................  75.312(b)(1), 75.312(b)(1)(ii).                               
    75.312(b)(1)(i).................................  75.312(b)(1)(ii)(A).                                          
    75.312(b)(1)(ii)................................  75.312(b)(1)(ii)(B).                                          
    75.312(c).......................................  75.312(c).                                                    
    75.312(d).......................................  75.312(d).                                                    
    75.312(f).......................................  75.312(f)(1).                                                 
    75.312(g)(1)....................................  75.312(g)(1).                                                 
    75.312(g)(3)....................................  75.312(g)(3).                                                 
    75.312(h).......................................  75.312(h).                                                    
    75.313(c)(2)....................................  75.313(c)(2).                                                 
    75.313(c)(3)....................................  75.313(c)(3).                                                 
    75.313(d)(1)(i).................................  75.313(d)(1)(i).                                              
    75.313(d)(1)(ii)................................  75.313(d)(1)(ii).                                             
    75.321(a).......................................  75.321(a)(1).                                                 
    75.321(a).......................................  75.321(a)(2).                                                 
    75.323(b)(1)(ii)................................  75.323(b)(1)(ii).                                             
    75.323(c)(1)....................................  75.323(c)(1).                                                 
    75.323(d)(2)(i).................................  75.323(d)(2)(i).                                              
    75.325(d).......................................  75.325(d).                                                    
    75.333(a).......................................  75.333(a).                                                    
    75.333(b)(1)....................................  75.333(b)(1).                                                 
    75.333(b)(3)....................................  75.333(b)(3).                                                 
    75.333(b)(4)....................................  75.333(b)(4).                                                 
    75.333(e)(1)....................................  75.333(e)(1)(i).                                              
    75.333(e)(1)....................................  75.333(e)(1)(ii).                                             
    75.334(e).......................................  75.334(e).                                                    
    75.334(f)(3)....................................  75.334(f)(3).                                                 
    75.340(a).......................................  75.340(a)                                                     
    75.340(a)(1)....................................  75.340(a)(1)(i).                                              
    75.340(a)(2)....................................  75.340(a)(1)(ii).                                             
    75.340(a)(3)....................................  75.340(a)(1)(iii).                                            
    75.340(a)(3)(i).................................  75.340(a)(1)(iii)(A).                                         
    75.340(a)(3)(ii)................................  75.340(a)(1)(iii)(B).                                         
    75.340(a).......................................  75.340(a)(2).                                                 
    75.340(a)(1)....................................  75.340(a)(2)(i).                                              
    75.340(a)(2)....................................  75.340(a)(2)(ii).                                             
    75.342(a)(4)....................................  75.342(a)(4).                                                 
    75.344(a).......................................  75.344(a).                                                    
    75.344(a)(1)....................................  75.344(a)(2).                                                 
    75.344(a)(2)....................................  75.344(b).                                                    
    75.344(b)(1)....................................  75.344(a)(1).                                                 
    75.344(b)(2)....................................  75.344(a)(2).                                                 
    75.344(b)(2)(i).................................  75.344(a)(2)(i).                                              
    
    [[Page 9826]]
                                                                                                                    
    75.344(b)(2)(ii)................................  75.344(a)(2)(ii).                                             
    75.360(a).......................................  75.360(a)(1).                                                 
    75.360(b).......................................  75.360(b).                                                    
    75.360(b)(1)....................................  75.360(b)(1).                                                 
    75.360(b)(3)....................................  75.360(b)(3).                                                 
    75.360(b)(4)....................................  75.350(b)(4).                                                 
    75.360(b)(6)....................................  75.360(b)(6)(i).                                              
    75.360(b)(6)....................................  75.360(b)(6)(ii).                                             
    75.360(c).......................................  75.360(c).                                                    
    75.360(c)(1)....................................  75.360(c)(1).                                                 
    75.360(c)(3.....................................  75.360(c)(3).                                                 
    75.360(e).......................................  75.363.                                                       
    75.360(f).......................................  75.360(e).                                                    
    75.360(g).......................................  75.360(f).                                                    
    75.360(h).......................................  75.360(g).                                                    
    75.362(a)(1)....................................  75.362(a)(1).                                                 
    75.363(a)(2)....................................  75.363.                                                       
    75.362(c)(1)....................................  75.362(c)(1).                                                 
    75.362(d)(1)(i).................................  75.362(d)(1)(ii).                                             
    75.362(d)(1)(ii)................................  75.362(d)(1)(iii).                                            
    75.362(d)(2)....................................  75.362(d)(2).                                                 
    75.362(g).......................................  75.363.                                                       
    75.362(h).......................................  75.363.                                                       
    75.364(a)(1)....................................  75.364(a)(1).                                                 
    75.364(a)(2)(i).................................  75.364(a)(2)(i).                                              
    75.364(a)(2)(ii)................................  75.364(a)(2)(ii).                                             
    75.364(a)(2)(iii)...............................  75.364(a)(2)(iii).                                            
    75.364(h).......................................  75.364(h).                                                    
    75.364(i).......................................  75.364(i).                                                    
    75.370(a)(3)....................................  75.370(a)(3).                                                 
    75.370(a)(3)....................................  75.370(a)(3)(ii).                                             
    75.370(a)(3)....................................  75.370(a)(3)(iii).                                            
    75.370(b)(1)....................................  75.370(c)(1).                                                 
    75.370(b)(2)....................................  75.370(c)(2).                                                 
    75.370(e).......................................  75.370(f).                                                    
    75.370(e).......................................  75.370(f)(2).                                                 
    75.370(e).......................................  75.370(f)(3).                                                 
    75.371(r).......................................  75.371(r).                                                    
    75.371(s).......................................  75.371(s).                                                    
    75.371(z).......................................  75.371(z).                                                    
    75.371(bb)......................................  75.371(bb).                                                   
    75.371(cc)......................................  75.371(cc).                                                   
    75.372(b)(3)....................................  75.372(b)(3).                                                 
    75.380(d)(3)....................................  75.380(d)(3).                                                 
    75.380(d)(4)(ii)................................  75.380(d)(4)(ii).                                             
    75.380(d)(5)....................................  75.380(d)(5).                                                 
    75.380(f).......................................  75.380(f).                                                    
    75.380(i)(2)....................................  75.380(i)(2).                                                 
    75.383(a).......................................  75.383(a).                                                    
    75.388(c).......................................  75.388(c).                                                    
    75.389(c)(1)....................................  75.389(c)(1).                                                 
    ----------------------------------------------------------------------------------------------------------------
    
    
    
    III. Paperwork Reduction Act
    
        The information collection requirements contained in this rule have 
    been submitted to the Office of Management and Budget (OMB) for review 
    under the Paperwork Reduction Act of 1995 (44 U.S.C. 3501-3520), as 
    implemented by OMB in regulations at 5 CFR part 1320. No person may be 
    required to respond to, or may be subjected to a penalty for failure to 
    comply with, these information collection requirements until they have 
    been approved and MSHA has announced the assigned OMB control number. 
    The OMB control number, when assigned, will be announced by separate 
    notice in the Federal Register. In accordance with Sec. 1320.11(h) of 
    the implementing regulations, OMB has 60 days from today's publication 
    date in which to approve, disapprove, or instruct MSHA to make a change 
    to the information collection requirements in this rule.
        This final rule addresses comments submitted to OMB and MSHA on the 
    collection of information requirements in the proposed rule. In 
    revising the requirements from those that appeared in the proposed 
    rule, MSHA has evaluated the necessity and usefulness of the 
    collections of information; reevaluated MSHA's estimate of the 
    information collection burden, including the validity of the underlying 
    methodology and assumptions; and minimized the burden on respondents 
    for the information collection requirements, to the extent possible. 
    This final rule provides for the use of electronic storage and 
    maintenance of records.
    
    Benefits
    
        In assessing costs and benefits of the ventilation rule, it is 
    important to note that ventilation of underground coal mines is the 
    primary method of preventing the accumulation of explosive methane gas, 
    controlling harmful respirable dust, and assuring the quality of air 
    miners breath. Because 
    
    [[Page 9827]]
    of the potential for a large number of fatalities resulting from 
    ventilation problems, MSHA has found it prudent to establish multiple 
    safety factors and safety work practices to better assure adequate 
    protection for miners. It is extremely difficult to specifically 
    quantify safety benefits related to each safety factor. However, due to 
    the close, confined nature of the workplace in an underground coal 
    mine, failure of any safety factors or protective actions related to 
    ventilation can have disastrous effects. The introduction of this rule 
    lists some of those tragic mine accidents. In the restricted work 
    environment of an underground coal mine, failure of a single safety 
    factor or noncompliance with a safe work practice could jeopardize the 
    well-being of all miners underground. The total effect of the 
    provisions in this final rule in conjunction with MSHA's existing 
    ventilation standards should decrease the occurrence of fatalities, 
    injuries, accidents, and illnesses in underground coal mines.
        With respect to this final rule, the Agency has identified nine 
    fatalities and seven injuries which potentially could have been 
    prevented by compliance with these provisions. In addition, the final 
    rule contains provisions to better assure compliance with the 
    respirable dust control parameters specified in the mine ventilation 
    plan. Adherence to these parameters helps to maintain a work 
    environment free of excessive levels of respirable dust, thereby 
    improving long-term health protection for miners and potentially 
    reducing the number of miners afflicted with coal workers' 
    pneumoconiosis.
        Some provisions clarify the intent of the existing rule. Such 
    clarifications should increase the likelihood of compliance and thereby 
    will help to increase the probability of preventing a fatality, injury, 
    or non-injury accident. For the provisions which offer an alternative 
    compliance option, the miners will be provided at least the same level 
    of safety provided by an existing requirement. These provisions will 
    facilitate compliance by the operator, thereby increasing the potential 
    for the rule to reduce the probability of a ventilation-related 
    explosion or accident.
        In conclusion, the Agency determined that these provisions will 
    increase the probability that compliance with the ventilation rule will 
    prevent future ventilation-related accidents and generate a safer 
    mining environment.
    
    Compliance Costs and Economic Impact
    
        MSHA has compared the costs associated with the existing 
    requirements with the costs of the new requirements. Based upon the 
    available data, MSHA estimates that compliance with the rule will 
    produce net total per year costs of approximately $4.0 million for the 
    mining industry. This $4.0 million is composed of approximately $0.6 
    million in net annualized costs (derived from $4.0 million one-time 
    costs) and approximately $3.4 million net annual recurring costs.
        With respect to large underground coal mines the net total per year 
    costs will be approximately $3.0 million. This $3.0 million is composed 
    of approximately $0.46 million in net annualized costs (derived from 
    $3.0 million one-time costs) and approximately $2.54 million net annual 
    recurring costs.
        With respect to small underground coal mines the net total per year 
    costs will be approximately $1.0 million. This $1.0 million is composed 
    of approximately $0.14 million in net annualized costs (derived from 
    $1.0 million one-time costs) and approximately $0.82 million net annual 
    recurring costs.
        Executive Order 12866 requires that regulatory agencies assess the 
    impact to the government for any regulation determined to be a 
    significant regulatory action. MSHA does not believe that this rule 
    will create any significant cost impacts to the government. The 
    regulation can be implemented under existing government practices 
    without any substantial equipment or facility expenditures by the 
    government.
        The incremental compliance costs for all underground coal mines are 
    listed by provision in Table I.
    
      Table IV-1.--Compliance Costs to Comply With the Ventilation Rule for 
                           all Underground Coal Mines                       
                            [In thousands of dollars]                       
    ------------------------------------------------------------------------
                                               First                        
                    Standard                    year   Annualized    Annual 
                                               costs      costs      costs  
    ------------------------------------------------------------------------
    75.301..................................    (100)        (7)        (20)
    75.310..................................     329         47         (70)
    75.311..................................  .......  ..........  .........
    75.312..................................  .......  ..........    (1,121)
    75.313..................................  .......  ..........       322 
    75.320..................................  .......  ..........  .........
    75.321..................................     250         35          40 
    75.323..................................  .......  ..........  .........
    75.330..................................  .......  ..........  .........
    75.333..................................  .......  ..........  .........
    75.334..................................  .......  ..........  .........
    75.340..................................      63          9             
    75.342..................................      12          2          38 
    75.344..................................      57         10       1,256 
    75.360..................................     123         17      (1,556)
    75.362..................................     420         59       3,275 
    75.363..................................  .......  ..........       321 
    75.364..................................  .......  ..........       682 
    75.370..................................  .......  ..........        67 
    75.371..................................  .......  ..........        13 
    75.372..................................  .......  ..........  .........
    75.380..................................   2,839        436          51 
    75.382..................................  .......  ..........        13 
    75.388..................................  .......  ..........        53 
    
    [[Page 9828]]
                                                                            
    75.389..................................                                
                                             -------------------------------
          Total costs.......................   3,993        608       3,364 
    ------------------------------------------------------------------------
    
    
    
    Regulatory Flexibility Certification
    
        The Regulatory Flexibility Act requires that agencies evaluate and 
    include, wherever possible, compliance alternatives that minimize any 
    adverse impact on small businesses when developing regulatory 
    standards. MSHA has not exempted small mines from any provision of the 
    rule and small mines will benefit from some of the provisions and the 
    alternative compliance methods.
        MSHA determined that these revisions will not generate a 
    substantial cost increase for small mines. The lack of a substantial 
    cost increase for small mines, in conjunction with the fact that 
    similar hazards exist in both large and small mining operations, 
    indicates that regulatory relief is not warranted for small mining 
    operations. Therefore, MSHA has determined that these provisions will 
    not have a significantly adverse impact upon a substantial number of 
    small entities.
        The incremental costs for small and large mines are listed by 
    provision in Table II.
    
      Table IV-2.--Compliance Costs to Comply With the Ventilation Rule for Small and Large Underground Coal Mines  
                                                [In thousands of dollars]                                           
    ----------------------------------------------------------------------------------------------------------------
                                            First year costs          Annualized costs            Annual costs      
                 Standard              -----------------------------------------------------------------------------
                                           Small        Large        Small        Large        Small        Large   
    ----------------------------------------------------------------------------------------------------------------
    75.301............................                     (100)                       (7)                      (20)
    75.310............................          273          56            39           8          (78)           8 
    75.311............................                                                                              
    75.312............................                                                                       (1,121)
    75.313............................                                                              55          267 
    75.320............................                                                                              
    75.321............................                      250                        35                        40 
    75.323............................                                                                              
    75.330............................                                                                              
    75.333............................                                                                              
    75.334............................                                                                              
    75.340............................            4          59             1           8                           
    75.342............................            6           6             1           1           18           20 
    75.344............................                       57                        10           43        1,213 
    75.360............................           37          86             5          12          100       (1,656)
    75.362............................           80         340            11          48          409        2,866 
    75.363............................                                                              98          223 
    75.364............................                                                             126          556 
    75.370............................                                                              12           55 
    75.371............................                                                               6            7 
    75.372............................                                                                              
    75.380............................          585       2,254            89         347            6           45 
    75.382............................                                                                           13 
    75.388............................                                                              25           28 
    75.389............................                                                                              
                                       -----------------------------------------------------------------------------
          Total.......................          985       3,008           146         462          820        2,544 
    ----------------------------------------------------------------------------------------------------------------
    
    List of Subjects in 30 CFR Part 75
    
        Escapeways, Mine safety and health, Underground coal mines, 
    Ventilation.
    
        Dated: March 4, 1996.
    J. Davitt McAteer,
    Assistant Secretary for Mine Safety and Health.
    
        Accordingly, part 75, subchapter O, chapter I, title 30 of the Code 
    of Federal Regulations is amended as follows:
    
    PART 75--MANDATORY SAFETY STANDARDS--UNDERGROUND COAL MINES
    
        1. The authority citation for part 75 is revised to read as 
    follows:
    
        Authority: 30 U.S.C. 811.
    
        2. Subpart D of part 75 is revised to read as follows: 
        
    [[Page 9829]]
    
    
    Subpart D--Ventilation
    
    Sec.
    75.300  Scope.
    75.301  Definitions.
    75.302  Main mine fans.
    75.310  Installation of main mine fans.
    75.311  Main mine fan operation.
    75.312  Main mine fan examinations and records.
    75.313  Main mine fan stoppage with persons underground.
    75.320  Air quality detectors and measurement devices.
    75.321  Air quality.
    75.322  Harmful quantities of noxious gases.
    75.323  Actions for excessive methane.
    75.324  Intentional changes in the ventilation system.
    75.325  Air quantity.
    75.326  Mean entry air velocity.
    75.327  Air courses and trolley haulage systems.
    75.330  Face ventilation control devices.
    75.331  Auxiliary fans and tubing.
    75.332  Working sections and working places.
    75.333  Ventilation controls.
    75.334  Worked-out areas and areas where pillars are being 
    recovered.
    75.335  Construction of seals.
    75.340  Underground electrical installations.
    75.341  Direct-fired intake air heaters.
    75.342  Methane monitors.
    75.343  Underground shops.
    75.344  Compressors.
    75.350  Air courses and belt haulage entries.
    75.351  Atmospheric monitoring system (AMS).
    75.352  Return air courses.
    75.360  Preshift examination.
    75.361  Supplemental examination.
    75.362  On-shift examination.
    75.363  Hazardous conditions; posting, correcting and recording.
    75.364  Weekly examination.
    75.370  Mine ventilation plan; submission and approval.
    75.371  Mine ventilation plan; contents.
    75.372  Mine ventilation map.
    75.373  Reopening mines.
    75.380  Escapeways; bituminous and lignite mines.
    75.381  Escapeways; anthracite mines.
    75.382  Mechanical escape facilities.
    75.383  Escapeway maps and drills.
    75.384  Longwall and shortwall travelways.
    75.385  Opening new mines.
    75.386  Final mining of pillars.
    75.388  Boreholes in advance of mining.
    75.389  Mining into inaccessible areas.
    
    
    Sec. 75.300  Scope.
    
        This subpart sets requirements for underground coal mine 
    ventilation.
    
    
    Sec. 75.301  Definitions.
    
        In addition to the applicable definitions in Sec. 75.2, the 
    following definitions apply in this subpart.
        Air course. An entry or a set of entries separated from other 
    entries by stoppings, overcasts, other ventilation control devices, or 
    by solid blocks of coal or rock so that any mixing of air currents 
    between each is limited to leakage.
        Incombustible. Incapable of being burned.
        Intake air. Air that has not yet ventilated the last working place 
    on any split of any working section, or any worked-out area, whether 
    pillared or nonpillared.
        Intrinsically safe. Incapable of releasing enough electrical or 
    thermal energy under normal or abnormal conditions to cause ignition of 
    a flammable mixture of methane or natural gas and air of the most 
    easily ignitable composition.
        Noncombustible Structure or Area. Describes a structure or area 
    that will continue to provide protection against flame spread for at 
    least 1 hour when subjected to a fire test incorporating an ASTM E119-
    88 time/temperature heat input, or equivalent.
        Noncombustible Material. Describes a material which when used to 
    construct a ventilation control results in a control that will continue 
    to serve its intended function for 1 hour when subjected to a fire test 
    incorporating an ASTM E119-88 time/temperature heat input, or 
    equivalent.
        Return air. Air that has ventilated the last working place on any 
    split of any working section or any worked-out area whether pillared or 
    nonpillared. If air mixes with air that has ventilated the last working 
    place on any split of any working section or any worked-out area, 
    whether pillared or nonpillared, it is considered return air. For the 
    purposes of Sec. 75.507-1, air that has been used to ventilate any 
    working place in a coal producing section or pillared area, or air that 
    has been used to ventilate any working face if such air is directed 
    away from the immediate return is return air. Notwithstanding the 
    definition of intake air, for the purpose of ventilation of structures, 
    areas or installations that are required by this subpart D to be 
    ventilated to return air courses, and for ventilation of seals, other 
    air courses may be designated as return air courses by the operator 
    only when the air in these air courses will not be used to ventilate 
    working places or other locations, structures, installations or areas 
    required to be ventilated with intake air.
        Worked-out area. An area where mining has been completed, whether 
    pillared or nonpillared, excluding developing entries, return air 
    courses, and intake air courses.
    
    
    Sec. 75.302  Main mine fans.
    
        Each coal mine shall be ventilated by one or more main mine fans. 
    Booster fans shall not be installed underground to assist main mine 
    fans except in anthracite mines. In anthracite mines, booster fans 
    installed in the main air current or a split of the main air current 
    may be used provided their use is approved in the ventilation plan.
    
    
    Sec. 75.310  Installation of main mine fans.
    
        (a) Each main mine fan shall be--
        (1) Installed on the surface in an incombustible housing;
        (2) Connected to the mine opening with incombustible air ducts;
        (3) Equipped with an automatic device that gives a signal at the 
    mine when the fan either slows or stops. A responsible person 
    designated by the operator shall always be at a surface location at the 
    mine where the signal can be seen or heard while anyone is underground. 
    This person shall be provided with two-way communication with the 
    working sections and work stations where persons are routinely assigned 
    to work for the majority of a shift;
        (4) Equipped with a pressure recording device or system. Mines 
    permitted to shut down main mine fans under Sec. 75.311 and which do 
    not have a pressure recording device installed on main mine fans shall 
    have until March 11, 1997 to install a pressure recording device or 
    system on all main mine fans. If a device or system other than a 
    circular pressure recorder is used to monitor main mine fan pressure, 
    the monitoring device or system shall provide a continuous graph or 
    continuous chart of the pressure as a function of time. At not more 
    than 7-day intervals, a hard copy of the continuous graph or chart 
    shall be generated or the record of the fan pressure shall be stored 
    electronically. When records of fan pressure are stored electronically, 
    the system used to store these records shall be secure and not 
    susceptible to alteration and shall be capable of storing the required 
    data. Records of the fan pressure shall be retained at a surface 
    location at the mine for at least 1 year and be made available for 
    inspection by authorized representatives of the Secretary and the 
    representative of miners;
        (5) Protected by one or more weak walls or explosion doors, or a 
    combination of weak walls and explosion doors, located in direct line 
    with possible explosive forces;
        (6) Except as provided under paragraph (e) of this section, offset 
    by at least 15 feet from the nearest side of the mine opening unless an 
    alternative method of protecting the fan and its associated components 
    is approved in the ventilation plan. 
    
    [[Page 9830]]
    
        (b)(1) If an electric motor is used to drive a main mine fan, the 
    motor shall operate from a power circuit independent of all mine power 
    circuits.
        (2) If an internal combustion engine is used to drive a main mine 
    fan--
        (i) The fuel supply shall be protected against fires and 
    explosions;
        (ii) The engine shall be installed in an incombustible housing and 
    be equipped with a remote shut-down device;
        (iii) The engine and the engine exhaust system shall be located out 
    of direct line of the air current exhausting from the mine; and
        (iv) The engine exhaust shall be vented to the atmosphere so that 
    the exhaust gases do not contaminate the mine intake air current or any 
    enclosure.
        (c) If a main mine fan monitoring system is used under Sec. 75.312, 
    the system shall--
        (1) Record, as described in paragraph (a)(4) the mine ventilating 
    pressure;
        (2) Monitor bearing temperature, revolutions per minute, vibration, 
    electric voltage, and amperage;
        (3) Provide a printout of the monitored parameters, including the 
    mine ventilating pressure within a reasonable period, not to exceed the 
    end of the next scheduled shift during which miners are underground; 
    and
        (4) Be equipped with an automatic device that signals when--
        (i) An electrical or mechanical deficiency exists in the monitoring 
    system; or
        (ii) A sudden increase or loss in mine ventilating pressure occurs.
        (5) Provide monitoring, records, printouts, and signals required by 
    paragraphs (c)(1) through (c)(4) at a surface location at the mine 
    where a responsible person designated by the operator is always on duty 
    and where signals from the monitoring system can be seen or heard while 
    anyone is underground. This person shall be provided with two-way 
    communication with the working sections and work stations where persons 
    are routinely assigned to work for the majority of a shift.
        (d) Weak walls and explosion doors shall have cross-sectional areas 
    at least equal to that of the entry through which the pressure from an 
    explosion underground would be relieved. A weak wall and explosion door 
    combination shall have a total cross-sectional area at least equal to 
    that of the entry through which the pressure from an explosion 
    underground would be relieved.
        (e) If a mine fan is installed in line with an entry, a slope, or a 
    shaft--
        (1) The cross-sectional area of the pressure relief entry shall be 
    at least equal to that of the fan entry;
        (2) The fan entry shall be developed out of direct line with 
    possible explosive forces;
        (3) The coal or other solid material between the pressure relief 
    entry and the fan entry shall be at least 2,500 square feet; and
        (4) The surface opening of the pressure relief entry shall be not 
    less than 15 feet nor more than 100 feet from the surface opening of 
    the fan entry and from the underground intersection of the fan entry 
    and pressure relief entry.
        (f) In mines ventilated by multiple main mine fans, incombustible 
    doors shall be installed so that if any main mine fan stops and air 
    reversals through the fan are possible, the doors on the affected fan 
    automatically close.
    
    
    Sec. 75.311  Main mine fan operation.
    
        (a) Main mine fans shall be continuously operated, except as 
    otherwise approved in the ventilation plan, or when intentionally 
    stopped for testing of automatic closing doors and automatic fan signal 
    devices, maintenance or adjustment of the fan, or to perform 
    maintenance or repair work underground that cannot otherwise be made 
    while the fan is operating.
        (b) Except as provided in paragraph (c) of this section, when a 
    main mine fan is intentionally stopped and the ventilating quantity 
    provided by the fan is not maintained by a back-up fan system--
        (1) Only persons necessary to evaluate the effect of the fan 
    stoppage or restart, or to perform maintenance or repair work that 
    cannot otherwise be made while the fan is operating, shall be permitted 
    underground;
        (2) Mechanized equipment shall be shut off before stopping the fan; 
    and
        (3) Electric power circuits entering underground areas of the mine 
    shall be deenergized.
        (c) When a back-up fan system is used that does not provide the 
    ventilating quantity provided by the main mine fan, persons may be 
    permitted in the mine and electric power circuits may be energized as 
    specified in the approved ventilation plan.
        (d) If an unusual variance in the mine ventilation pressure is 
    observed, or if an electrical or mechanical deficiency of a main mine 
    fan is detected, the mine foreman or equivalent mine official, or in 
    the absence of the mine foreman or equivalent mine official, a 
    designated certified person acting for the mine foreman or equivalent 
    mine official shall be notified immediately, and appropriate action or 
    repairs shall be instituted promptly.
        (e) While persons are underground, a responsible person designated 
    by the operator shall always be at a surface location where each main 
    mine fan signal can be seen or heard.
        (f) The area within 100 feet of main mine fans and intake air 
    openings shall be kept free of combustible material, unless alternative 
    precautions necessary to provide protection from fire or other products 
    of combustion are approved in the ventilation plan.
        (g) If multiple mine fans are used, the mine ventilation system 
    shall be designed and maintained to eliminate areas without air 
    movement.
        (h) Any atmospheric monitoring system operated during fan stoppages 
    shall be intrinsically safe.
    
    
    Sec. 75.312  Main mine fan examinations and records.
    
        (a) To assure electrical and mechanical reliability of main mine 
    fans, each main mine fan and its associated components, including 
    devices for measuring or recording mine ventilation pressure, shall be 
    examined for proper operation by a trained person designated by the 
    operator. Examinations of main mine fans shall be made at least once 
    each day that the fan operates, unless a fan monitoring system is used. 
    No examination is required on any day when no one, including certified 
    persons, goes underground, except that an examination shall be 
    completed prior to anyone entering the mine.
        (b)(1) If a main mine fan monitoring system is used, a trained 
    person designated by the operator shall--
        (i) At least once each day review the data provided by the fan 
    monitoring system to assure that the fan and the fan monitoring system 
    are operating properly. No review is required on any day when no one, 
    including certified persons, goes underground, except that a review of 
    the data shall be performed prior to anyone entering the underground 
    portion of the mine. Data reviewed should include the fan pressure, 
    bearing temperature, revolutions per minute, vibration, electric 
    voltage, and amperage; and
        (ii) At least every 7 days--
        (A) Test the monitoring system for proper operation; and
        (B) Examine each main mine fan and its associated components to 
    assure electrical and mechanical reliability of main mine fans.
        (2) If the monitoring system malfunctions, the malfunction shall be 
    corrected, or paragraph (a) of this section shall apply.
        (c) At least every 31 days, the automatic fan signal device for 
    each main mine fan shall be tested by stopping the fan. Only persons 
    
    [[Page 9831]]
    necessary to evaluate the effect of the fan stoppage or restart, or to 
    perform maintenance or repair work that cannot otherwise be made while 
    the fan is operating, shall be permitted underground. Notwithstanding 
    the requirement of Sec. 75.311(b)(3), underground power may remain 
    energized during this test provided no one, including persons 
    identified in Sec. 75.311(b)(1), is underground. If the fan is not 
    restarted within 15 minutes, underground power shall be deenergized and 
    no one shall enter any underground area of the mine until the fan is 
    restarted and an examination of the mine is conducted as described in 
    Sec. 75.360 (b) through (e) and the mine has been determined to be 
    safe.
        (d) At least every 31 days, the automatic closing doors in multiple 
    main mine fan systems shall be tested by stopping the fan. Only persons 
    necessary to evaluate the effect of the fan stoppage or restart, or to 
    perform maintenance or repair work that cannot otherwise be made while 
    the fan is operating, shall be permitted underground. Notwithstanding 
    the provisions of Sec. 75.311, underground power may remain energized 
    during this test provided no one, including persons identified in 
    Sec. 75.311(b)(1), is underground. If the fan is not restarted within 
    15 minutes, underground power shall be deenergized and no one shall 
    enter any underground area of the mine, until the fan is restarted and 
    an examination of the mine is conducted as described in Sec. 75.360 (b) 
    through (e) and the mine has been determined to be safe.
        (e) Circular main mine fan pressure recording charts shall be 
    changed before the beginning of a second revolution.
        (f)(1) Certification. Persons making main mine fan examinations 
    shall certify by initials and date at the fan or another location 
    specified by the operator that the examinations were made. Each 
    certification shall identify the main mine fan examined.
        (2) Persons reviewing data produced by a main mine fan monitoring 
    system shall certify by initials and date on a printed copy of the data 
    from the system that the review was completed. In lieu of certification 
    on a copy of the data, the person reviewing the data may certify 
    electronically that the review was completed. Electronic certification 
    shall be by handwritten initials and date in a computer system so as to 
    be secure and not susceptible to alteration.
        (g)(1) Recordkeeping. By the end of the shift on which the 
    examination is made, persons making main mine fan examinations shall 
    record all uncorrected defects that may affect the operation of the fan 
    that are not corrected by the end of that shift. Records shall be 
    maintained in a secure book that is not susceptible to alteration or 
    electronically in a computer system so as to be secure and not 
    susceptible to alteration.
        (2) When a fan monitoring system is used in lieu of the daily fan 
    examination--
        (i) The certified copies of data produced by fan monitoring systems 
    shall be maintained separate from other computer-generated reports or 
    data; and
        (ii) A record shall be made of any fan monitoring system 
    malfunctions, electrical or mechanical deficiencies in the monitoring 
    system and any sudden increase or loss in mine ventilating pressure. 
    The record shall be made by the end of the shift on which the review of 
    the data is completed and shall be maintained in a secure book that is 
    not susceptible to alteration or electronically in a computer system so 
    as to be secure and not susceptible to alteration.
        (3) By the end of the shift on which the monthly test of the 
    automatic fan signal device or the automatic closing doors is 
    completed, persons making these tests shall record the results of the 
    tests. Records shall be maintained in a secure book that is not 
    susceptible to alteration or electronically in a computer system so as 
    to be secure and not susceptible to alteration.
        (h) Retention period. Records, including records of mine fan 
    pressure and the certified copies of data produced by fan monitoring 
    systems, shall be retained at a surface location at the mine for at 
    least 1 year and shall be made available for inspection by authorized 
    representatives of the Secretary and the representative of miners.
    
    
    Sec. 75.313  Main mine fan stoppage with persons underground.
    
        (a) If a main mine fan stops while anyone is underground and the 
    ventilating quantity provided by the fan is not maintained by a back-up 
    fan system--
        (1) Electrically powered equipment in each working section shall be 
    deenergized;
        (2) Other mechanized equipment in each working section shall be 
    shut off; and
        (3) Everyone shall be withdrawn from the working sections and areas 
    where mechanized mining equipment is being installed or removed.
        (b) If ventilation is restored within 15 minutes after a main mine 
    fan stops, certified persons shall examine for methane in the working 
    places and in other areas where methane is likely to accumulate before 
    work is resumed and before equipment is energized or restarted in these 
    areas.
        (c) If ventilation is not restored within 15 minutes after a main 
    mine fan stops--
        (1) Everyone shall be withdrawn from the mine;
        (2) Underground electric power circuits shall be deenergized. 
    However, circuits necessary to withdraw persons from the mine need not 
    be deenergized if located in areas or haulageways where methane is not 
    likely to migrate to or accumulate. These circuits shall be deenergized 
    as persons are withdrawn; and
        (3) Mechanized equipment not located on working sections shall be 
    shut off. However, mechanized equipment necessary to withdraw persons 
    from the mine need not be shut off if located in areas where methane is 
    not likely to migrate to or accumulate.
        (d)(1) When ventilation is restored--
        (i) No one other than designated certified examiners shall enter 
    any underground area of the mine until an examination is conducted as 
    described in Sec. 75.360(b) through (e) and the area has been 
    determined to be safe. Designated certified examiners shall enter the 
    underground area of the mine from which miners have been withdrawn only 
    after the fan has operated for at least 15 minutes unless a longer 
    period of time is specified in the approved ventilation plan.
        (ii) Underground power circuits shall not be energized and 
    nonpermissible mechanized equipment shall not be started or operated in 
    an area until an examination is conducted as described in 
    Sec. 75.360(b) through (e) and the area has been determined to be safe, 
    except that designated certified examiners may use nonpermissible 
    transportation equipment in intake airways to facilitate the making of 
    the required examination.
        (2) If ventilation is restored to the mine before miners reach the 
    surface, the miners may return to underground working areas only after 
    an examination of the areas is made by a certified person and the areas 
    are determined to be safe.
        (e) Any atmospheric monitoring system operated during fan stoppages 
    shall be intrinsically safe.
    
    
    Sec. 75.320  Air quality detectors and measurement devices.
    
        (a) Tests for methane shall be made by a qualified person with MSHA 
    approved detectors that are maintained in permissible and proper 
    operating condition and calibrated with a known 
    
    [[Page 9832]]
    methane-air mixture at least once every 31 days.
        (b) Tests for oxygen deficiency shall be made by a qualified person 
    with MSHA approved oxygen detectors that are maintained in permissible 
    and proper operating condition and that can detect 19.5 percent oxygen 
    with an accuracy of 0.5 percent. The oxygen detectors shall 
    be calibrated at the start of each shift that the detectors will be 
    used.
        (c) Handheld devices that contain electrical components and that 
    are used for measuring air velocity, carbon monoxide, oxides of 
    nitrogen, and other gases shall be approved and maintained in 
    permissible and proper operating condition.
        (d) An oxygen detector approved by MSHA shall be used to make tests 
    for oxygen deficiency required by the regulations in this part. 
    Permissible flame safety lamps may only be used as a supplementary 
    testing device.
        (e) Maintenance of instruments required by paragraphs (a) through 
    (d) of this section shall be done by persons trained in such 
    maintenance.
    
    
    Sec. 75.321  Air quality.
    
        (a)(1) The air in areas where persons work or travel, except as 
    specified in paragraph (a)(2) of this section, shall contain at least 
    19.5 percent oxygen and not more than 0.5 percent carbon dioxide, and 
    the volume and velocity of the air current in these areas shall be 
    sufficient to dilute, render harmless, and carry away flammable, 
    explosive, noxious, and harmful gases, dusts, smoke, and fumes.
        (2) The air in areas of bleeder entries and worked-out areas where 
    persons work or travel shall contain at least 19.5 percent oxygen, and 
    carbon dioxide levels shall not exceed 0.5 percent time weighted 
    average and 3.0 percent short term exposure limit.
        (b) Notwithstanding the provisions of Sec. 75.322, for the purpose 
    of preventing explosions from gases other than methane, the following 
    gases shall not be permitted to accumulate in excess of the 
    concentrations listed below:
        (1) Carbon monoxide (CO)--2.5 percent
        (2) Hydrogen (H2)--.80 percent
        (3) Hydrogen sulfide (H2S)--.80 percent
        (4) Acetylene (C2H2)--.40 percent
        (5) Propane (C3H8)--.40 percent
        (6) MAPP (methyl-acetylene-propylene-propodiene)--.30 percent
    
    
    Sec. 75.322  Harmful quantities of noxious gases.
    
        Concentrations of noxious or poisonous gases, other than carbon 
    dioxide, shall not exceed the current threshold limit values (TLV) as 
    specified and applied by the ACGIH. Detectors or laboratory analysis of 
    mine air samples shall be used to determine the concentrations of 
    harmful, noxious, or poisonous gases.
    
    
    Sec. 75.323  Actions for excessive methane.
    
        (a) Location of tests. Tests for methane concentrations under this 
    section shall be made at least 12 inches from the roof, face, ribs, and 
    floor.
        (b) Working places and intake air courses.
        (1) When 1.0 percent or more methane is present in a working place 
    or an intake air course, including an air course in which a belt 
    conveyor is located, or in an area where mechanized mining equipment is 
    being installed or removed--
        (i) Except intrinsically safe atmospheric monitoring systems (AMS), 
    electrically powered equipment in the affected area shall be 
    deenergized, and other mechanized equipment shall be shut off;
        (ii) Changes or adjustments shall be made at once to the 
    ventilation system to reduce the concentration of methane to less than 
    1.0 percent; and
        (iii) No other work shall be permitted in the affected area until 
    the methane concentration is less than 1.0 percent.
        (2) When 1.5 percent or more methane is present in a working place 
    or an intake air course, including an air course in which a belt 
    conveyor is located, or in an area where mechanized mining equipment is 
    being installed or removed--
        (i) Everyone except those persons referred to in Sec. 104(c) of the 
    Act shall be withdrawn from the affected area; and
        (ii) Except for intrinsically safe AMS, electrically powered 
    equipment in the affected area shall be disconnected at the power 
    source.
        (c) Return air split. (1) When 1.0 percent or more methane is 
    present in a return air split between the last working place on a 
    working section and where that split of air meets another split of air, 
    or the location at which the split is used to ventilate seals or 
    worked-out areas changes or adjustments shall be made at once to the 
    ventilation system to reduce the concentration of methane in the return 
    air to less than 1.0 percent.
        (2) When 1.5 percent or more methane is present in a return air 
    split between the last working place on a working section and where 
    that split of air meets another split of air, or the location where the 
    split is used to ventilate seals or worked-out areas--
        (i) Everyone except those persons referred to in Sec. 104(c) of the 
    Act shall be withdrawn from the affected area;
        (ii) Other than intrinsically safe AMS, equipment in the affected 
    area shall be deenergized, electric power shall be disconnected at the 
    power source, and other mechanized equipment shall be shut off; and
        (iii) No other work shall be permitted in the affected area until 
    the methane concentration in the return air is less than 1.0 percent.
        (d) Return air split alternative. (1) The provisions of this 
    paragraph apply if--
        (i) The quantity of air in the split ventilating the active 
    workings is at least 27,000 cubic feet per minute in the last open 
    crosscut or the quantity specified in the approved ventilation plan, 
    whichever is greater;
        (ii) The methane content of the air in the split is continuously 
    monitored during mining operations by an AMS that gives a visual and 
    audible signal on the working section when the methane in the return 
    air reaches 1.5 percent, and the methane content is monitored as 
    specified in Sec. 75.351; and
        (iii) Rock dust is continuously applied with a mechanical duster to 
    the return air course during coal production at a location in the air 
    course immediately outby the most inby monitoring point.
        (2) When 1.5 percent or more methane is present in a return air 
    split between a point in the return opposite the section loading point 
    and where that split of air meets another split of air or where the 
    split of air is used to ventilate seals or worked-out areas--
        (i) Changes or adjustments shall be made at once to the ventilation 
    system to reduce the concentration of methane in the return air below 
    1.5 percent;
        (ii) Everyone except those persons referred to in Sec. 104(c) of 
    the Act shall be withdrawn from the affected area;
        (iii) Except for intrinsically safe AMS, equipment in the affected 
    area shall be deenergized, electric power shall be disconnected at the 
    power source, and other mechanized equipment shall be shut off; and
        (iv) No other work shall be permitted in the affected area until 
    the methane concentration in the return air is less than 1.5 percent.
        (e) Bleeders and other return air courses. The concentration of 
    methane in a bleeder split of air immediately before the air in the 
    split joins another split of air, or in a return air course other than 
    as described in paragraphs (c) and (d) of this section, shall not 
    exceed 2.0 percent.
    
    [[Page 9833]]
    
    
    
    Sec. 75.324  Intentional changes in the ventilation system.
    
        (a) A person designated by the operator shall supervise any 
    intentional change in ventilation that--
        (1) Alters the main air current or any split of the main air 
    current in a manner that could materially affect the safety or health 
    of persons in the mine; or
        (2) Affects section ventilation by 9,000 cubic feet per minute of 
    air or more in bituminous or lignite mines, or 5,000 cubic feet per 
    minute of air or more in anthracite mines.
        (b) Intentional changes shall be made only under the following 
    conditions:
        (1) Electric power shall be removed from areas affected by the 
    ventilation change and mechanized equipment in those areas shall be 
    shut off before the ventilation change begins.
        (2) Only persons making the change in ventilation shall be in the 
    mine.
        (3) Electric power shall not be restored to the areas affected by 
    the ventilation change and mechanized equipment shall not be restarted 
    until a certified person has examined these areas for methane 
    accumulation and for oxygen deficiency and has determined that the 
    areas are safe.
    
    
    Sec. 75.325  Air quantity.
    
        (a)(1) In bituminous and lignite mines the quantity of air shall be 
    at least 3,000 cubic feet per minute reaching each working face where 
    coal is being cut, mined, drilled for blasting, or loaded. When a 
    greater quantity is necessary to dilute, render harmless, and carry 
    away flammable, explosive, noxious, and harmful gases, dusts, smoke, 
    and fumes, this quantity shall be specified in the approved ventilation 
    plan. A minimum air quantity may be required to be specified in the 
    approved ventilation plan for other working places or working faces.
        (2) The quantity of air reaching the working face shall be 
    determined at or near the face end of the line curtain, ventilation 
    tubing, or other ventilation control device. If the curtain, tubing, or 
    device extends beyond the last row of permanent roof supports, the 
    quantity of air reaching the working face shall be determined behind 
    the line curtain or in the ventilation tubing at or near the last row 
    of permanent supports.
        (3) If machine mounted dust collectors or diffuser fans are used, 
    the approved ventilation plan shall specify the operating volume of the 
    dust collector or diffuser fan.
        (b) In bituminous and lignite mines, the quantity of air reaching 
    the last open crosscut of each set of entries or rooms on each working 
    section and the quantity of air reaching the intake end of a pillar 
    line shall be at least 9,000 cubic feet per minute unless a greater 
    quantity is required to be specified in the approved ventilation plan.
        (c) In longwall and shortwall mining systems--
        (1) The quantity of air shall be at least 30,000 cubic feet per 
    minute reaching the working face of each longwall, unless the operator 
    demonstrates that a lesser air quantity will maintain continual 
    compliance with applicable methane and respirable dust standards. This 
    lesser quantity shall be specified in the approved ventilation plan. A 
    quantity greater than 30,000 cubic feet per minute may be required to 
    be specified in the approved ventilation plan.
        (2) The velocity of air that will be provided to control methane 
    and respirable dust below applicable standards on each longwall or 
    shortwall and the locations where these velocities will be provided 
    shall be specified in the approved ventilation plan. The locations 
    specified shall be at least 50 feet but no more than 100 feet from the 
    headgate and tailgate, respectively.
        (d) Ventilation shall be maintained during installation and removal 
    of mechanized mining equipment. The approved ventilation plan shall 
    specify the minimum quantity of air, the locations where this quantity 
    will be provided and the ventilation controls required.
        (e) In anthracite mines, the quantity of air shall be as follows:
        (1) At least 1,500 cubic feet per minute reaching each working face 
    where coal is being mined, unless a greater quantity is required to be 
    specified in the approved ventilation plan.
        (2) At least 5,000 cubic feet per minute passing through the last 
    open crosscut in each set of entries or rooms and at the intake end of 
    any pillar line, unless a greater quantity is required to be specified 
    in the approved ventilation plan.
        (3) When robbing areas where air currents cannot be controlled and 
    air measurements cannot be obtained, the air shall have perceptible 
    movement.
    
    
    Sec. 75.326  Mean entry air velocity.
    
        In exhausting face ventilation systems, the mean entry air velocity 
    shall be at least 60 feet per minute reaching each working face where 
    coal is being cut, mined, drilled for blasting, or loaded, and to any 
    other working places as required in the approved ventilation plan. A 
    lower mean entry air velocity may be approved in the ventilation plan 
    if the lower velocity will maintain methane and respirable dust 
    concentrations below the applicable levels. Mean entry air velocity 
    shall be determined at or near the inby end of the line curtain, 
    ventilation tubing, or other face ventilation control devices.
    
    
    Sec. 75.327  Air courses and trolley haulage systems.
    
        (a) In any mine opened on or after March 30, 1970, or in any new 
    working section of a mine opened before that date, where trolley 
    haulage systems are maintained and where trolley wires or trolley 
    feeder wires are installed, an authorized representative of the 
    Secretary shall require enough entries or rooms as intake air courses 
    to limit the velocity of air currents in the haulageways to minimize 
    the hazards of fires and dust explosions in the haulageways.
        (b) Unless the district manager approves a higher velocity, the 
    velocity of the air current in the trolley haulage entries shall be 
    limited to not more than 250 feet per minute. A higher air velocity may 
    be required to limit the methane content in these haulage entries or 
    elsewhere in the mine to less than 1.0 percent and provide an adequate 
    supply of oxygen.
    
    
    Sec. 75.330  Face ventilation control devices.
    
        (a) Brattice cloth, ventilation tubing and other face ventilation 
    control devices shall be made of flame-resistant material approved by 
    MSHA.
        (b)(1) Ventilation control devices shall be used to provide 
    ventilation to dilute, render harmless, and to carry away flammable, 
    explosive, noxious, and harmful gases, dusts, smoke, and fumes--
        (i) To each working face from which coal is being cut, mined, 
    drilled for blasting, or loaded; and
        (ii) To any other working places as required by the approved 
    ventilation plan.
        (2) These devices shall be installed at a distance no greater than 
    10 feet from the area of deepest penetration to which any portion of 
    the face has been advanced unless an alternative distance is specified 
    and approved in the ventilation plan. Alternative distances specified 
    shall be capable of maintaining concentrations of respirable dust, 
    methane, and other harmful gases below the levels specified in the 
    applicable sections of this chapter.
        (c) When the line brattice or any other face ventilation control 
    device is damaged to an extent that ventilation of the working face is 
    inadequate, production activities in the working place shall cease 
    until necessary repairs 
    
    [[Page 9834]]
    are made and adequate ventilation is restored.
    
    
    Sec. 75.331  Auxiliary fans and tubing.
    
        (a) When auxiliary fans and tubing are used for face ventilation, 
    each auxiliary fan shall be--
        (1) Permissible, if the fan is electrically operated;
        (2) Maintained in proper operating condition;
        (3) Deenergized or shut off when no one is present on the working 
    section; and
        (4) Located and operated to avoid recirculation of air.
        (b) If a deficiency exists in any auxiliary fan system, the 
    deficiency shall be corrected or the auxiliary fan shall be deenergized 
    immediately.
        (c) If the air passing through an auxiliary fan or tubing contains 
    1.0 percent or more methane, power to electrical equipment in the 
    working place and to the auxiliary fan shall be deenergized, and other 
    mechanized equipment in the working place shall be shut off until the 
    methane concentration is reduced to less than 1.0 percent.
        (d) When an auxiliary fan is stopped--
        (1) Line brattice or other face ventilation control devices shall 
    be used to maintain ventilation to affected faces; and
        (2) Electrical equipment in the affected working places shall be 
    disconnected at the power source, and other mechanized equipment shall 
    be shut off until ventilation to the working place is restored.
    
    
    Sec. 75.332  Working sections and working places.
    
        (a)(1) Each working section and each area where mechanized mining 
    equipment is being installed or removed, shall be ventilated by a 
    separate split of intake air directed by overcasts, undercasts or other 
    permanent ventilation controls.
        (2) When two or more sets of mining equipment are simultaneously 
    engaged in cutting, mining, or loading coal or rock from working places 
    within the same working section, each set of mining equipment shall be 
    on a separate split of intake air.
        (3) For purposes of this section, a set of mining equipment 
    includes a single loading machine, a single continuous mining machine, 
    or a single longwall or shortwall mining machine.
        (b)(1) Air that has passed through any area that is not examined 
    under Secs. 75.360, 75.361 or 75.364 of this subpart, or through an 
    area where second mining has been done shall not be used to ventilate 
    any working place. Second mining is intentional retreat mining where 
    pillars have been wholly or partially removed, regardless of the amount 
    of recovery obtained.
        (2) Air that has passed by any opening of any unsealed area that is 
    not examined under Secs. 75.360, 75.361 or 75.364 of this subpart, 
    shall not be used to ventilate any working place.
    
    
    Sec. 75.333  Ventilation controls.
    
        (a) For purposes of this section, ``doors'' include any door 
    frames.
        (b) Permanent stoppings or other permanent ventilation control 
    devices constructed after November 15, 1992, shall be built and 
    maintained--
        (1) Between intake and return air courses, except temporary 
    controls may be used in rooms that are 600 feet or less from the 
    centerline of the entry from which the room was developed including 
    where continuous face haulage systems are used in such rooms. Unless 
    otherwise approved in the ventilation plan, these stoppings or controls 
    shall be maintained to and including the third connecting crosscut 
    outby the working face;
        (2) To separate belt conveyor haulageways from return air courses, 
    except where belt entries in areas of mines developed before March 30, 
    1970, are used as return air courses;
        (3) To separate belt conveyor haulageways from intake air courses 
    when the air in the intake air courses is used to provide air to active 
    working places. Temporary ventilation controls may be used in rooms 
    that are 600 feet or less from the centerline of the entry from which 
    the rooms were developed including where continuous face haulage 
    systems are used in such rooms. When continuous face haulage systems 
    are used, permanent stoppings or other permanent ventilation control 
    devices shall be built and maintained to the outby most point of travel 
    of the dolly or 600 feet from the point of deepest penetration in the 
    conveyor belt entry, whichever distance is closer to the point of 
    deepest penetration, to separate the continuous haulage entry from the 
    intake entries;
        (4) To separate the primary escapeway from belt and trolley haulage 
    entries, as required by Sec. 75.380(g). For the purposes of 
    Sec. 75.380(g), the loading point for a continuous haulage system shall 
    be the outby most point of travel of the dolly or 600 feet from the 
    point of deepest penetration, whichever distance is less; and
        (5) In return air courses to direct air into adjacent worked-out 
    areas.
        (c) Personnel doors shall be constructed of noncombustible material 
    and shall be of sufficient strength to serve their intended purpose of 
    maintaining separation and permitting travel between air courses, and 
    shall be installed as follows in permanent stoppings constructed after 
    November 15, 1992:
        (1) The distance between personnel doors shall be no more than 300 
    feet in seam heights below 48 inches and 600 feet in seam heights 48 
    inches or higher.
        (2) The location of all personnel doors in stoppings along 
    escapeways shall be clearly marked so that the doors may be easily 
    identified by anyone traveling in the escapeway and in the entries on 
    either side of the doors.
        (3) When not in use, personnel doors shall be closed.
        (d) Doors, other than personnel doors, constructed after November 
    15, 1992, that are used in lieu of permanent stoppings or to control 
    ventilation within an air course shall be:
        (1) Made of noncombustible material or coated on all accessible 
    surfaces with flame-retardant material having a flame-spread index of 
    25 or less, as tested under ASTM E162-87.
        (2) Of sufficient strength to serve their intended purpose of 
    maintaining separation and permitting travel between or within air 
    courses or entries.
        (3) Installed in pairs to form an airlock. When an airlock is used, 
    one side of the airlock shall remain closed. When not in use, both 
    sides shall be closed.
        (e)(1)(i) Except as provided in paragraphs (e)(2), (e)(3) and 
    (e)(4) of this section all overcasts, undercasts, shaft partitions, 
    permanent stoppings, and regulators, installed after March 11, 1997, 
    shall be constructed in a traditionally accepted method and of 
    materials that have been demonstrated to perform adequately or in a 
    method and of materials that have been tested and shown to have a 
    minimum strength equal to or greater than the traditionally accepted 
    in-mine controls. Tests may be performed under ASTM E72-80 Section 12--
    Transverse Load-Specimen Vertical, load only, or the operator may 
    conduct comparative in-mine tests. In-mine tests shall be designed to 
    demonstrate the comparative strength of the proposed construction and a 
    traditionally accepted in-mine control.
        (ii) All overcasts, undercasts, shaft partitions, permanent 
    stoppings, and regulators, installed after November 15, 1992, shall be 
    constructed of noncombustible material. Materials that are suitable for 
    the construction of overcasts, undercasts, shaft partitions, permanent 
    stoppings, and regulators include concrete, concrete block, brick, 
    cinder block, tile, or steel. No ventilation controls installed after 
    
    [[Page 9835]]
    November 15, 1992, shall be constructed of aluminum.
        (2) In anthracite mines, permanent stoppings may be constructed of 
    overlapping layers of hardwood mine boards, if the stoppings are a 
    minimum 2 inches thick.
        (3) When timbers are used to create permanent stoppings in heaving 
    or caving areas, the stoppings shall be coated on all accessible 
    surfaces with a flame-retardant material having a flame-spread index of 
    25 or less, as tested under ASTM E162-87, ``Surface Flammability of 
    Materials Using a Radiant Heat Energy Source.''
        (4) In anthracite mines, doors and regulators may be constructed of 
    overlapping layers of hardwood boards, if the doors, door frames, and 
    regulators are a minimum 2 inches thick.
        (f) When sealants are applied to ventilation controls, the sealant 
    shall have a flame-spread index of 25 or less under ASTM E162-87.
        (g) Before mining is discontinued in an entry or room that is 
    advanced more than 20 feet from the inby rib, a crosscut shall be made 
    or line brattice shall be installed and maintained to provide adequate 
    ventilation. When conditions such as methane liberation warrant a 
    distance less than 20 feet, the approved ventilation plan shall specify 
    the location of such rooms or entries and the maximum distance they 
    will be developed before a crosscut is made or line brattice is 
    installed.
        (h) All permanent ventilation controls, including seals, shall be 
    maintained to serve the purpose for which they were built.
    
    
    Sec. 75.334  Worked-out areas and areas where pillars are being 
    recovered.
    
        (a) Worked-out areas where no pillars have been recovered shall 
    be--
        (1) Ventilated so that methane-air mixtures and other gases, dusts, 
    and fumes from throughout the worked-out areas are continuously diluted 
    and routed into a return air course or to the surface of the mine; or
        (2) Sealed.
        (b)(1) During pillar recovery a bleeder system shall be used to 
    control the air passing through the area and to continuously dilute and 
    move methane-air mixtures and other gases, dusts, and fumes from the 
    worked-out area away from active workings and into a return air course 
    or to the surface of the mine.
        (2) After pillar recovery a bleeder system shall be maintained to 
    provide ventilation to the worked-out area, or the area shall be 
    sealed.
        (c) The approved ventilation plan shall specify the following:
        (1) The design and use of bleeder systems;
        (2) The means to determine the effectiveness of bleeder systems;
        (3) The means for adequately maintaining bleeder entries free of 
    obstructions such as roof falls and standing water; and
        (4) The location of ventilating devices such as regulators, 
    stoppings and bleeder connectors used to control air movement through 
    the worked-out area.
        (d) If the bleeder system used does not continuously dilute and 
    move methane-air mixtures and other gases, dusts, and fumes away from 
    worked-out areas into a return air course or to the surface of the 
    mine, or it cannot be determined by examinations or evaluations under 
    Sec. 75.364 that the bleeder system is working effectively, the worked-
    out area shall be sealed.
        (e) Each mining system shall be designed so that each worked-out 
    area can be sealed. The approved ventilation plan shall specify the 
    location and the sequence of construction of proposed seals.
        (f) In place of the requirements of paragraphs (a) and (b) of this 
    section, for mines with a demonstrated history of spontaneous 
    combustion, or that are located in a coal seam determined to be 
    susceptible to spontaneous combustion, the approved ventilation plan 
    shall specify the following:
        (1) Measures to detect methane, carbon monoxide, and oxygen 
    concentrations during and after pillar recovery, and in worked-out 
    areas where no pillars have been recovered, to determine if the areas 
    must be ventilated or sealed.
        (2) Actions that will be taken to protect miners from the hazards 
    of spontaneous combustion.
        (3) If a bleeder system will not be used, the methods that will be 
    used to control spontaneous combustion, accumulations of methane-air 
    mixtures, and other gases, dusts, and fumes in the worked-out area.
    
    
    Sec. 75.335  Construction of seals.
    
        (a)(1) Each seal constructed after November 15, 1992, shall be--
        (i) Constructed of solid concrete blocks at least 6 by 8 by 16 
    inches, laid in a transverse pattern with mortar between all joints;
        (ii) Hitched into solid ribs to a depth of at least 4 inches and 
    hitched at least 4 inches into the floor;
        (iii) At least 16 inches thick. When the thickness of the seal is 
    less than 24 inches and the width is greater than 16 feet or the height 
    is greater than 10 feet, a pilaster shall be interlocked near the 
    center of the seal. The pilaster shall be at least 16 inches by 32 
    inches; and
        (iv) Coated on all accessible surfaces with flame-retardant 
    material that will minimize leakage and that has a flame-spread index 
    of 25 or less, as tested under ASTM E162-87, ``Surface Flammability of 
    Materials Using a Radiant Heat Energy Source.''
        (2) Alternative methods or materials may be used to create a seal 
    if they can withstand a static horizontal pressure of 20 pounds per 
    square inch provided the method of installation and the material used 
    approved in the ventilation plan. If the alternative methods or 
    materials include the use of timbers, the timbers also shall be coated 
    on all accessible surfaces with flame-retardant material having a 
    flame-spread index 25 or less, as tested under ASTM E162-87.
        (b) A sampling pipe or pipes shall be installed in each set of 
    seals for a worked-out area. Each pipe shall--
        (1) Extend into the sealed area a sufficient distance (at least 15 
    feet) to obtain a representative sample from behind the seal;
        (2) Be equipped with a cap or shut-off valve; and
        (3) Be installed with the sampling end of the pipe about 12 inches 
    from the roof.
        (c)(1) A corrosion-resistant water pipe or pipes shall be installed 
    in seals at the low points of the area being sealed and at all other 
    locations necessary when water accumulation within the sealed area is 
    possible; and
        (2) Each water pipe shall have a water trap installed on the outby 
    side of the seal.
    
    
    Sec. 75.340  Underground electrical installations.
    
        (a) Underground transformer stations, battery charging stations, 
    substations, rectifiers, and water pumps shall be housed in 
    noncombustible structures or areas or be equipped with a fire 
    suppression system meeting the requirements of Sec. 75.1107-3 through 
    Sec. 75.1107-16.
        (1) When a noncombustible structure or area is used, these 
    installations shall be--
        (i) Ventilated with intake air that is coursed into a return air 
    course or to the surface and that is not used to ventilate working 
    places; or
        (ii) Ventilated with intake air that is monitored for carbon 
    monoxide or smoke by an AMS installed and operated according to 
    Sec. 75.351. Monitoring of intake air ventilating battery charging 
    stations shall be done with sensors not affected by hydrogen; or
        (iii) Ventilated with intake air and equipped with sensors to 
    monitor for heat and for carbon monoxide or smoke. Monitoring of intake 
    air ventilating battery charging stations shall be done 
    
    [[Page 9836]]
    with sensors not affected by hydrogen. The sensors shall deenergize 
    power to the installation, activate a visual and audible alarm located 
    outside of and on the intake side of the enclosure, and activate doors 
    that will automatically close when either of the following occurs:
        (A) The temperature in the noncombustible structure reaches 165 
    deg.F; or
        (B) The carbon monoxide concentration reaches 10 parts per million 
    above the ambient level for the area, or the optical density of smoke 
    reaches 0.022 per meter. At least every 31 days, sensors installed to 
    monitor for carbon monoxide shall be calibrated with a known 
    concentration of carbon monoxide and air sufficient to activate the 
    closing door, or each smoke sensor shall be tested to determine that it 
    functions correctly.
        (2) When a fire suppression system is used, these installations 
    shall be--
        (i) Ventilated with intake air that is coursed into a return air 
    course or to the surface and that is not used to ventilate working 
    places; or
        (ii) Ventilated with intake air that is monitored for carbon 
    monoxide or smoke by an AMS installed and operated according to 
    Sec. 75.351. Monitoring of intake air ventilating battery charging 
    stations shall be done with sensors not affected by hydrogen.
        (b) This section does not apply to--
        (1) Rectifiers and power centers with transformers that are either 
    dry-type or contain nonflammable liquid, if they are located at or near 
    the section and are moved as the working section advances or retreats;
        (2) Submersible pumps;
        (3) Permissible pumps and associated permissible switchgear;
        (4) Pumps located on or near the section and that are moved as the 
    working section advances or retreats;
        (5) Pumps installed in anthracite mines; and
        (6) Small portable pumps.
    
    
    Sec. 75.341  Direct-fired intake air heaters.
    
        (a) If any system used to heat intake air malfunctions, the heaters 
    affected shall switch off automatically.
        (b) Thermal overload devices shall protect the blower motor from 
    overheating.
        (c) The fuel supply shall turn off automatically if a flame-out 
    occurs.
        (d) Each heater shall be located or guarded to prevent contact by 
    persons and shall be equipped with a screen at the inlet to prevent 
    combustible materials from passing over the burner units.
        (e) If intake air heaters use liquefied fuel systems--
        (1) Hydrostatic relief valves installed on vaporizers and on 
    storage tanks shall be vented; and
        (2) Fuel storage tanks shall be located or protected to prevent 
    fuel from leaking into the mine.
        (f) Following any period of 8 hours or more during which a heater 
    does not operate, the heater and its associated components shall be 
    examined within its first hour of operation. Additionally, each heater 
    and its components shall be examined at least once each shift that the 
    heater operates. The examination shall include measurement of the 
    carbon monoxide concentration at the bottom of each shaft, slope, or in 
    the drift opening where air is being heated. The measurements shall be 
    taken by a person designated by the operator or by a carbon monoxide 
    sensor that is calibrated with a known concentration of carbon monoxide 
    and air at least once every 31 days. When the carbon monoxide 
    concentration at this location reaches 50 parts per million, the heater 
    causing the elevated carbon monoxide level shall be shut down.
    
    
    Sec. 75.342  Methane monitors.
    
        (a)(1) MSHA approved methane monitors shall be installed on all 
    face cutting machines, continuous miners, longwall face equipment, 
    loading machines, and other mechanized equipment used to extract or 
    load coal within the working place.
        (2) The sensing device for methane monitors on longwall shearing 
    machines shall be installed at the return air end of the longwall face. 
    An additional sensing device also shall be installed on the longwall 
    shearing machine, downwind and as close to the cutting head as 
    practicable. An alternative location or locations for the sensing 
    device required on the longwall shearing machine may be approved in the 
    ventilation plan.
        (3) The sensing devices of methane monitors shall be installed as 
    close to the working face as practicable.
        (4) Methane monitors shall be maintained in permissible and proper 
    operating condition and shall be calibrated with a known air-methane 
    mixture at least once every 31 days. To assure that methane monitors 
    are properly maintained and calibrated, the operator shall:
        (i) Use persons properly trained in the maintenance, calibration, 
    and permissibility of methane monitors to calibrate and maintain the 
    devices.
        (ii) Maintain a record of all calibration tests of methane 
    monitors. Records shall be maintained in a secure book that is not 
    susceptible to alteration or electronically in a computer system so as 
    to be secure and not susceptible to alteration.
        (iii) Retain the record of calibration tests for 1 year from the 
    date of the test. Records shall be retained at a surface location at 
    the mine and made available for inspection by authorized 
    representatives of the Secretary and the representative of miners.
        (b)(1) When the methane concentration at any methane monitor 
    reaches 1.0 percent the monitor shall give a warning signal.
        (2) The warning signal device of the methane monitor shall be 
    visible to a person who can deenergize the equipment on which the 
    monitor is mounted.
        (c) The methane monitor shall automatically deenergize the machine 
    on which it is mounted when--
        (1) The methane concentration at any methane monitor reaches 2.0 
    percent; or
        (2) The monitor is not operating properly.
    
    
    Sec. 75.343  Underground shops.
    
        (a) Underground shops shall be equipped with an automatic fire 
    suppression system meeting the requirements of Sec. 75.1107-3 through 
    Sec. 75.1107-16, or be enclosed in a noncombustible structure or area.
        (b) Underground shops shall be ventilated with intake air that is 
    coursed directly into a return air course.
    
    
    Sec. 75.344  Compressors.
    
        (a) Except compressors that are components of equipment such as 
    locomotives and rock dusting machines and compressors of less than 5 
    horsepower, electrical compressors including those that may start 
    automatically shall be:
        (1) Continuously attended by a person designated by the operator 
    who can see the compressor at all times during its operation. Any 
    designated person attending the compressor shall be capable of 
    activating the fire suppression system and deenergizing or shutting-off 
    the compressor in the event of a fire; or,
        (2) Enclosed in a noncombustible structure or area which is 
    ventilated by intake air coursed directly into a return air course or 
    to the surface and equipped with sensors to monitor for heat and for 
    carbon monoxide or smoke. The sensors shall deenergize power to the 
    compressor, activate a visual and audible alarm located outside of and 
    on the intake side of the enclosure, and activate doors to 
    automatically enclose the noncombustible structure or area when either 
    of the following occurs:
        (i) The temperature in the noncombustible structure or area reaches 
    165  deg.F. 
    
    [[Page 9837]]
    
        (ii) The carbon monoxide concentration reaches 10 parts per million 
    above the ambient level for the area, or the optical density of smoke 
    reaches 0.022 per meter. At least once every 31 days, sensors installed 
    to monitor for carbon monoxide shall be calibrated with a known 
    concentration of carbon monoxide and air sufficient to activate the 
    closing door, and each smoke sensor shall be tested to determine that 
    it functions correctly.
        (b) Compressors, except those exempted in paragraph (a), shall be 
    equipped with a heat activated fire suppression system meeting the 
    requirements of 75.1107-3 through 75.1107-16.
        (c) Two portable fire extinguishers or one extinguisher having at 
    least twice the minimum capacity specified for a portable fire 
    extinguisher in Sec. 75.1100-1(e) shall be provided for each 
    compressor.
        (d) In addition to electrical compressors, this section shall apply 
    to diesel compressors.
        (e) Notwithstanding the requirements of Sec. 75.1107-4, upon 
    activation of any fire suppression system used under paragraph (b) of 
    this section, the compressor shall be automatically deenergized or 
    automatically shut off.
    
    
    Sec. 75.350  Air courses and belt haulage entries.
    
        In any coal mine opened after March 30, 1970, the entries used as 
    intake and return air courses shall be separated from belt haulage 
    entries, and each operator of such mine shall limit the velocity of the 
    air coursed through belt haulage entries to the amount necessary to 
    provide an adequate supply of oxygen in such entries, and to insure 
    that the air therein shall contain less than 1.0 volume per centum of 
    methane, and such air shall not be used to ventilate active working 
    places. Whenever an authorized representative of the Secretary finds, 
    in the case of any coal mine opened on or prior to March 30, 1970, that 
    has been developed with more than two entries, that the conditions in 
    the entries, other than belt haulage entries, are such as to permit 
    adequately the coursing of intake or return air through such entries:
        (a) The belt haulage entries shall not be used to ventilate, unless 
    such entries are necessary to ventilate, active working places, and
        (b) When the belt haulage entries are not necessary to ventilate 
    the active working places, the operator of such mine shall limit the 
    velocity of the air coursed through the belt haulage entries to the 
    amount necessary to provide an adequate supply of oxygen in such 
    entries, and to assure that air therein shall contain less than 1.0 
    volume per centum of methane.
    
    
    Sec. 75.351  Atmospheric monitoring system (AMS).
    
        (a) Minimum requirements. An AMS shall consist of sensors to 
    monitor the mine atmosphere and instruments at a surface location 
    designated by the operator to receive information from the monitoring 
    sensors. Each AMS installed in accordance with Secs. 75.323(d)(1)(ii), 
    75.340(a)(2) and 75.362(f) shall do the following:
        (1) Monitor for circuit continuity and sensor function, and 
    identify at the designated surface location any activated or 
    malfunctioning sensor.
        (2) Signal a designated surface location at the mine when any 
    interruption of circuit continuity occurs or any sensor malfunctions.
        (3) Signal affected working sections and the designated surface 
    location when--
        (i) The carbon monoxide concentration at any carbon monoxide sensor 
    reaches 5 parts per million above the established ambient level for 
    that area; or
        (ii) The methane concentration at any methane monitoring station 
    exceeds the maximum allowable concentration as specified for that 
    location in Sec. 75.323.
        (4) Activate alarms at a designated surface location and affected 
    working sections when the carbon monoxide concentration at any carbon 
    monoxide sensor reaches 10 parts per million above the established 
    ambient level for the area or when the optical density of smoke at any 
    smoke sensor reaches 0.05 per meter.
        (b) Return splits. (1) If used to monitor return air splits under 
    Sec. 75.362(f), AMS sensors shall monitor the mine atmosphere for 
    percentage of methane in each return split of air from each working 
    section between the last working place, or longwall or shortwall face, 
    ventilated by that air split and the junction of that return air split 
    with another air split, seal, or worked-out area. If auxiliary fans and 
    tubing are used, the sensor also shall be located outby the auxiliary 
    fan discharge.
        (2) If used to monitor air splits under Sec. 75.323(d)(1)(ii), AMS 
    sensors shall monitor the mine atmosphere at the following locations:
        (i) In the return air course opposite the section loading point or, 
    if auxiliary fans and tubing are used, in the return air course outby 
    the auxiliary fans and a point opposite the section loading point.
        (ii) Immediately inby the location where the split of air meets 
    another split of air, or inby the location where the split of air is 
    used to ventilate seals or worked-out areas.
        (c) Electrical installations. If used to monitor the intake air 
    ventilating underground transformer stations, battery charging 
    stations, substations, rectifiers, or water pumps under 
    Sec. 75.340(a)(2), at least one sensor shall be installed to monitor 
    the mine atmosphere for carbon monoxide or smoke at least 50 feet and 
    no more than 100 feet downstream in the direction of air flow.
        (d) Signals and alarms. (1) A person designated by the operator 
    shall be at a surface location where the signals and alarms from the 
    AMS can always be seen or heard while anyone is underground. This 
    person shall have access to two-way communication with working sections 
    and with other identifiable duty stations underground. A mine map 
    showing the underground monitoring system shall be posted at the 
    surface location.
        (2) If a signal from any AMS sensor is activated, the monitor 
    producing the signal shall be identified, an examination shall be made 
    to determine the cause of the activation, and appropriate action shall 
    be taken.
        (e) Sensors. (1) Each carbon monoxide sensor shall be capable of 
    detecting carbon monoxide in air at a level of 1 part per 
    million throughout the operating range.
        (2) Each methane sensor shall be capable of detecting 1.0 percent 
    methane in air with an accuracy of 0.2 percent methane.
        (3) Each smoke sensor shall be capable of detecting the optical 
    density of smoke with an accuracy of 0.005 per meter.
        (f) Testing and calibration. At least once every 31 days--
        (1) Each carbon monoxide sensor shall be calibrated with a known 
    concentration of carbon monoxide and air sufficient to activate an 
    alarm;
        (2) Each smoke sensor shall be functionally tested;
        (3) Each methane sensor shall be calibrated with a known methane-
    air mixture; and
        (4) Each oxygen sensor shall be calibrated with air having a known 
    oxygen concentration.
        (g) Intrinsic Safety. Components of AMS installed in areas where 
    permissible equipment is required shall be intrinsically safe.
        (h) Recordkeeping. If a signal device or alarm is activated, a 
    record shall be made of the date, time, type of sensor, and the reason 
    for its activation. Also the maximum concentration detected at 
    
    [[Page 9838]]
    the sensor producing the signal shall be recorded.
        (i) Retention period. Records shall be retained for at least 1 year 
    at a surface location at the mine and made available for inspection by 
    authorized representatives of the Secretary and representatives of 
    miners.
    
    
    Sec. 75.352  Return air courses.
    
        Entries used as return air courses shall be separated from belt 
    haulage entries by permanent ventilation controls.
    
    
    Sec. 75.360  Preshift examination.
    
        (a)(1) Except as provided in paragraph (a)(2) of this section, a 
    certified person designated by the operator shall make a preshift 
    examination within 3 hours preceding the beginning of any 8-hour 
    interval during which any person is scheduled to work or travel 
    underground. The operator shall establish the 8-hour intervals of time 
    subject to the required preshift examinations. No person other than 
    certified examiners may enter or remain in any underground area unless 
    a preshift examination has been completed for the established 8-hour 
    period.
        (2) Preshift examinations of areas where pumpers are scheduled to 
    work or travel shall not be required prior to the pumper entering the 
    areas if the pumper is a certified person and the pumper conducts an 
    examination for hazardous conditions, tests for methane and oxygen 
    deficiency and determines if the air is moving in its proper direction 
    in the area where the pumper works or travels. The examination of the 
    area must be completed before the pumper performs any other work. A 
    record of all hazardous conditions found by the pumper shall be made 
    and retained in accordance with Sec. 75.363.
        (b) The person conducting the preshift examination shall examine 
    for hazardous conditions, test for methane and oxygen deficiency, and 
    determine if the air is moving in its proper direction at the following 
    locations:
        (1) Roadways, travelways and track haulageways where persons are 
    scheduled, prior to the beginning of the preshift examination, to work 
    or travel during the oncoming shift.
        (2) Belt conveyors that will be used to transport persons during 
    the oncoming shift and the entries in which these belt conveyors are 
    located.
        (3) Working sections and areas where mechanized mining equipment is 
    being installed or removed, if anyone is scheduled to work on the 
    section or in the area during the oncoming shift. The scope of the 
    examination shall include the working places, approaches to worked-out 
    areas and ventilation controls on these sections and in these areas, 
    and the examination shall include tests of the roof, face and rib 
    conditions on these sections and in these areas.
        (4) Approaches to worked-out areas along intake air courses and at 
    the entries used to carry air into worked-out areas if the intake air 
    passing the approaches is used to ventilate working sections where 
    anyone is scheduled to work during the oncoming shift. The examination 
    of the approaches to the worked-out areas shall be made in the intake 
    air course immediately inby and outby each entry used to carry air into 
    the worked-out area. An examination of the entries used to carry air 
    into the worked-out areas shall be conducted at a point immediately 
    inby the intersection of each entry with the intake air course.
        (5) Seals along intake air courses where intake air passes by a 
    seal to ventilate working sections where anyone is scheduled to work 
    during the oncoming shift.
        (6)(i) Entries and rooms developed after November 15, 1992, and 
    developed more than 2 crosscuts off an intake air course without 
    permanent ventilation controls where intake air passes through or by 
    these entries or rooms to reach a working section where anyone is 
    scheduled to work during the oncoming shift; and,
        (ii) Entries and rooms developed after November 15, 1992, and 
    driven more than 20 feet off an intake air course without a crosscut 
    and without permanent ventilation controls where intake air passes 
    through or by these entries or rooms to reach a working section where 
    anyone is scheduled to work during the oncoming shift.
        (7) Where unattended diesel equipment is to operate or areas where 
    trolley wires or trolley feeder wires are to be or will remain 
    energized during the oncoming shift.
        (8) High spots along intake air courses where methane is likely to 
    accumulate, if equipment will be operated in the area during the shift.
        (9) Underground electrical installations referred to in 
    Sec. 75.340(a), except those pumps listed in Sec. 75.340 (b)(2) through 
    (b)(6), and areas where compressors subject to Sec. 75.344 are 
    installed if the electrical installation or compressor is or will be 
    energized during the shift.
        (10) Other areas where work or travel during the oncoming shift is 
    scheduled prior to the beginning of the preshift examination.
        (c) The person conducting the preshift examination shall determine 
    the volume of air entering each of the following areas if anyone is 
    scheduled to work in the areas during the oncoming shift:
        (1) In the last open crosscut of each set of entries or rooms on 
    each working section and areas where mechanized mining equipment is 
    being installed or removed. The last open crosscut is the crosscut in 
    the line of pillars containing the permanent stoppings that separate 
    the intake air courses and the return air courses.
        (2) On each longwall or shortwall in the intake entry or entries at 
    the intake end of the longwall or shortwall face immediately outby the 
    face and the velocity of air at each end of the face at the locations 
    specified in the approved ventilation plan.
        (3) At the intake end of any pillar line--
        (i) If a single split of air is used, in the intake entry furthest 
    from the return air course, immediately outby the first open crosscut 
    outby the line of pillars being mined; or
        (ii) If a split system is used, in the intake entries of each split 
    immediately inby the split point.
        (d) The district manager may require the certified person to 
    examine other areas of the mine or examine for other hazards during the 
    preshift examination.
        (e) Certification. At each working place examined, the person doing 
    the preshift examination shall certify by initials, date, and the time, 
    that the examination was made. In areas required to be examined outby a 
    working section, the certified person shall certify by initials, date, 
    and the time at enough locations to show that the entire area has been 
    examined.
        (f) Recordkeeping. A record of the results of each preshift 
    examination, including a record of hazardous conditions and their 
    locations found by the examiner during each examination and of the 
    results and locations of air and methane measurements, shall be made on 
    the surface before any persons, other than certified persons conducting 
    examinations required by this subpart, enter any underground area of 
    the mine. The results of methane tests shall be recorded as the 
    percentage of methane measured by the examiner. The record shall be 
    made by the certified person who made the examination or by a person 
    designated by the operator. If the record is made by someone other than 
    the examiner, the examiner shall verify the record by initials and date 
    by or at the end of the shift for which the examination was made. A 
    record shall also be made by a certified person of the action taken to 
    correct hazardous conditions found during the preshift 
    
    [[Page 9839]]
    examination. All preshift and corrective action records shall be 
    countersigned by the mine foreman or equivalent mine official by the 
    end of the mine foreman's or equivalent mine official's next regularly 
    scheduled working shift. The records required by this section shall be 
    made in a secure book that is not susceptible to alteration or 
    electronically in a computer system so as to be secure and not 
    susceptible to alteration.
        (g) Retention period. Records shall be retained at a surface 
    location at the mine for at least 1 year and shall be made available 
    for inspection by authorized representatives of the Secretary and the 
    representative of miners.
    
    
    Sec. 75.361  Supplemental examination.
    
        (a) Except for certified persons conducting examinations required 
    by this subpart, within 3 hours before anyone enters an area in which a 
    preshift examination has not been made for that shift, a certified 
    person shall examine the area for hazardous conditions, determine 
    whether the air is traveling in its proper direction and at its normal 
    volume, and test for methane and oxygen deficiency.
        (b) Certification. At each working place examined, the person 
    making the supplemental examination shall certify by initials, date, 
    and the time, that the examination was made. In areas required to be 
    examined outby a working section, the certified person shall certify by 
    initials, date, and the time at enough locations to show that the 
    entire area has been examined.
    
    
    Sec. 75.362  On-shift examination.
    
        (a) (1) At least once during each shift, or more often if necessary 
    for safety, a certified person designated by the operator shall conduct 
    an on-shift examination of each section where anyone is assigned to 
    work during the shift and any area where mechanized mining equipment is 
    being installed or removed during the shift. The certified person shall 
    check for hazardous conditions, test for methane and oxygen deficiency, 
    and determine if the air is moving in its proper direction.
        (2) A person designated by the operator shall conduct an 
    examination to assure compliance with the respirable dust control 
    parameters specified in the mine ventilation plan. In those instances 
    when a shift change is accomplished without an interruption in 
    production on a section, the examination shall be made anytime within 1 
    hour of the shift change. In those instances when there is an 
    interruption in production during the shift change, the examination 
    shall be made before production begins on a section. Deficiencies in 
    dust controls shall be corrected before production begins or resumes. 
    The examination shall include air quantities and velocities, water 
    pressures and flow rates, excessive leakage in the water delivery 
    system, water spray numbers and orientations, section ventilation and 
    control device placement, and any other dust suppression measures 
    required by the ventilation plan. Additional measurements of the air 
    velocity and quantity, water pressure and flow rates are not required 
    if continuous monitoring of these controls is used and indicates that 
    the dust controls are functioning properly.
        (b) During each shift that coal is produced, a certified person 
    shall examine for hazardous conditions along each belt conveyor 
    haulageway where a belt conveyor is operated. This examination may be 
    conducted at the same time as the preshift examination of belt 
    conveyors and belt conveyor haulageways, if the examination is 
    conducted within 3 hours before the oncoming shift.
        (c) Persons conducting the on-shift examination shall determine at 
    the following locations:
        (1) The volume of air in the last open crosscut of each set of 
    entries or rooms on each section and areas where mechanized mining 
    equipment is being installed or removed. The last open crosscut is the 
    crosscut in the line of pillars containing the permanent stoppings that 
    separate the intake air courses and the return air courses.
        (2) The volume of air on a longwall or shortwall, including areas 
    where longwall or shortwall equipment is being installed or removed, in 
    the intake entry or entries at the intake end of the longwall or 
    shortwall.
        (3) The velocity of air at each end of the longwall or shortwall 
    face at the locations specified in the approved ventilation plan.
        (4) The volume of air at the intake end of any pillar line--
        (i) Where a single split of air is used in the intake entry 
    furthest from the return air course immediately outby the first open 
    crosscut outby the line of pillars being mined; or
        (ii) Where a split system is used in the intake entries of each 
    split immediately inby the split point.
        (d) (1) A qualified person shall make tests for methane--
        (i) At the start of each shift at each working place before 
    electrically operated equipment is energized; and
        (ii) Immediately before equipment is energized, taken into, or 
    operated in a working place; and
        (iii) At 20-minute intervals, or more often if required in the 
    approved ventilation plan at specific locations, during the operation 
    of equipment in the working place.
        (2) These methane tests shall be made at the face from under 
    permanent roof support, using extendable probes or other acceptable 
    means. When longwall or shortwall mining systems are used, these 
    methane tests shall be made at the shearer, the plow, or the cutting 
    head. When mining has been stopped for more than 20 minutes, methane 
    tests shall be conducted prior to the start up of equipment.
        (e) If auxiliary fans and tubing are used, they shall be inspected 
    frequently.
        (f) During each shift that coal is produced and at intervals not 
    exceeding 4 hours, tests for methane shall be made by a certified 
    person or by an atmospheric monitoring system (AMS) in each return 
    split of air from each working section between the last working place, 
    or longwall or shortwall face, ventilated by that split of air and the 
    junction of the return air split with another air split, seal, or 
    worked-out area. If auxiliary fans and tubing are used, the tests shall 
    be made at a location outby the auxiliary fan discharge.
        (g) Certification. (1) The person conducting the on-shift 
    examination in belt haulage entries shall certify by initials, date, 
    and time that the examination was made. The certified person shall 
    certify by initials, date, and the time at enough locations to show 
    that the entire area has been examined.
        (2) The person directing the on-shift examination to assure 
    compliance with the respirable dust control parameters specified in the 
    mine ventilation plan shall certify by initials, date, and time that 
    the examination was made.
    
    
    Sec. 75.363  Hazardous conditions; posting, correcting and recording.
    
        (a) Any hazardous condition found by the mine foreman or equivalent 
    mine official, assistant mine foreman or equivalent mine official, or 
    other certified persons designated by the operator for the purposes of 
    conducting examinations under this subpart D, shall be posted with a 
    conspicuous danger sign where anyone entering the areas would pass. A 
    hazardous condition, other than one detected during a preshift 
    examination or an examination conducted following a fan stoppage and 
    restart under Sec. 75.313(d)(1)(i), shall be corrected immediately or 
    the area shall remain posted until the hazardous condition is 
    corrected. If the condition creates an imminent danger, everyone except 
    those persons referred to in 
    
    [[Page 9840]]
    section 104(c) of the Act shall be withdrawn from the area affected to 
    a safe area until the hazardous condition is corrected. Only persons 
    designated by the operator to correct or evaluate the condition may 
    enter the posted area.
        (b) A record shall be made of any hazardous condition found. This 
    record shall be kept in a book maintained for this purpose on the 
    surface at the mine. The record shall be made by the completion of the 
    shift on which the hazardous condition is found and shall include the 
    nature and location of the hazardous condition and the corrective 
    action taken. This record shall not be required for shifts when no 
    hazardous conditions are found or for hazardous conditions found during 
    the preshift or weekly examinations inasmuch as these examinations have 
    separate recordkeeping requirements.
        (c) The record shall be made by the certified person who conducted 
    the examination or a person designated by the operator. If made by a 
    person other than the certified person, the certified person shall 
    verify the record by initials and date by or at the end of the shift 
    for which the examination was made. Records shall be countersigned by 
    the mine foreman or equivalent mine official by the end of the mine 
    foreman's or equivalent mine official's next regularly scheduled 
    working shift. The record shall be made in a secure book that is not 
    susceptible to alteration or electronically in a computer system so as 
    to be secure and not susceptible to alteration.
        (d) Retention period. Records shall be retained at a surface 
    location at the mine for at least 1 year and shall be made available 
    for inspection by authorized representatives of the Secretary and the 
    representative of miners.
    
    
    Sec. 75.364  Weekly examination.
    
        (a) Worked-out areas. (1) At least every 7 days, a certified person 
    shall examine unsealed worked-out areas where no pillars have been 
    recovered by traveling to the area of deepest penetration; measuring 
    methane and oxygen concentrations and air quantities and making tests 
    to determine if the air is moving in the proper direction in the area. 
    The locations of measurement points where tests and measurements will 
    be performed shall be included in the mine ventilation plan and shall 
    be adequate in number and location to assure ventilation and air 
    quality in the area. Air quantity measurements shall also be made where 
    the air enters and leaves the worked-out area. An alternative method of 
    evaluating the ventilation of the area may be approved in the 
    ventilation plan.
        (2) At least every 7 days, a certified person shall evaluate the 
    effectiveness of bleeder systems required by Sec. 75.334 as follows:
        (i) Measurements of methane and oxygen concentrations and air 
    quantity and a test to determine if the air is moving in its proper 
    direction shall be made where air enters the worked-out area.
        (ii) Measurements of methane and oxygen concentrations and air 
    quantity and a test to determine if the air is moving in the proper 
    direction shall be made immediately before the air enters a return 
    split of air.
        (iii) At least one entry of each set of bleeder entries used as 
    part of a bleeder system under Sec. 75.334 shall be traveled in its 
    entirety. Measurements of methane and oxygen concentrations and air 
    quantities and a test to determine if the air is moving in the proper 
    direction shall be made at the measurement point locations specified in 
    the mine ventilation plan to determine the effectiveness of the bleeder 
    system.
        (iv) In lieu of the requirements of paragraphs (a)(2)(i) and (iii) 
    of this section, an alternative method of evaluation may be specified 
    in the ventilation plan provided the alternative method results in 
    proper evaluation of the effectiveness of the bleeder system.
        (b) Hazardous conditions. At least every 7 days, an examination for 
    hazardous conditions at the following locations shall be made by a 
    certified person designated by the operator:
        (1) In at least one entry of each intake air course, in its 
    entirety, so that the entire air course is traveled.
        (2) In at least one entry of each return air course, in its 
    entirety, so that the entire air course is traveled.
        (3) In each longwall or shortwall travelway in its entirety, so 
    that the entire travelway is traveled.
        (4) At each seal along return and bleeder air courses and at each 
    seal along intake air courses not examined under Sec. 75.360(b)(5).
        (5) In each escapeway so that the entire escapeway is traveled.
        (6) On each working section not examined under Sec. 75.360(b)(3) 
    during the previous 7 days.
        (7) At each water pump not examined during a preshift examination 
    conducted during the previous 7 days.
        (c) Measurements and tests. At least every 7 days, a certified 
    person shall--
        (1) Determine the volume of air entering the main intakes and in 
    each intake split;
        (2) Determine the volume of air and test for methane in the last 
    open crosscut in any pair or set of developing entries or rooms, in the 
    return of each split of air immediately before it enters the main 
    returns, and where the air leaves the main returns; and
        (3) Test for methane in the return entry nearest each set of seals 
    immediately after the air passes the seals.
        (d) Hazardous conditions shall be corrected immediately. If the 
    condition creates an imminent danger, everyone except those persons 
    referred to in Sec. 104(c) of the Act shall be withdrawn from the area 
    affected to a safe area until the hazardous condition is corrected.
        (e) The weekly examination may be conducted at the same time as the 
    preshift or on-shift examinations.
        (f) (1) The weekly examination is not required during any 7 day 
    period in which no one enters any underground area of the mine.
        (2) Except for certified persons required to make examinations, no 
    one shall enter any underground area of the mine if a weekly 
    examination has not been completed within the previous 7 days.
        (g) Certification. The person making the weekly examinations shall 
    certify by initials, date, and the time that the examination was made. 
    Certifications and times shall appear at enough locations to show that 
    the entire area has been examined.
        (h) Recordkeeping. At the completion of any shift during which a 
    portion of a weekly examination is conducted, a record of the results 
    of each weekly examination, including a record of hazardous conditions 
    found during each examination and their locations, the corrective 
    action taken, and the results and location of air and methane 
    measurements, shall be made. The results of methane tests shall be 
    recorded as the percentage of methane measured by the examiner. The 
    record shall be made by the person making the examination or a person 
    designated by the operator. If made by a person other than the 
    examiner, the examiner shall verify the record by the initials and date 
    by or at the end of the shift for which the examination was made. The 
    record shall be countersigned by the mine foreman or equivalent mine 
    official by the end of the mine foreman's or equivalent mine official's 
    next regularly scheduled working shift. The records required by this 
    section shall be made in a secure book that is not susceptible to 
    alteration or electronically in a computer system so as to be secure 
    and not susceptible to alteration.
        (i) Retention period. Records shall be retained at a surface 
    location at the mine for at least 1 year and shall be made available 
    for inspection by authorized 
    
    [[Page 9841]]
    representatives of the Secretary and the representative of miners.
    
    
    Sec. 75.370  Mine ventilation plan; submission and approval.
    
        (a) (1) The operator shall develop and follow a ventilation plan 
    approved by the district manager. The plan shall be designed to control 
    methane and respirable dust and shall be suitable to the conditions and 
    mining system at the mine. The ventilation plan shall consist of two 
    parts, the plan content as prescribed in Sec. 75.371 and the 
    ventilation map with information as prescribed in Sec. 75.372. Only 
    that portion of the map which contains information required under 
    Sec. 75.371 will be subject to approval by the district manager.
        (2) The proposed ventilation plan and any revision to the plan 
    shall be submitted in writing to the district manager. When revisions 
    to a ventilation plan are proposed, only the revised pages, maps, or 
    sketches of the plan need to be submitted. When required in writing by 
    the district manager, the operator shall submit a fully revised plan by 
    consolidating the plan and all revisions in an orderly manner and by 
    deleting all outdated material.
        (3) (i) The mine operator shall notify the representative of miners 
    at least 5 days prior to submission of a mine ventilation plan and any 
    revision to a mine ventilation plan. If requested, the mine operator 
    shall provide a copy to the representative of miners at the time of 
    notification. In the event of a situation requiring immediate action on 
    a plan revision, notification of the revision shall be given, and if 
    requested, a copy of the revision shall be provided, to the 
    representative of miners by the operator at the time of submittal;
        (ii) A copy of the proposed ventilation plan, and a copy of any 
    proposed revision, submitted for approval shall be made available for 
    inspection by the representative of miners; and
        (iii) A copy of the proposed ventilation plan, and a copy of any 
    proposed revision, submitted for approval shall be posted on the mine 
    bulletin board at the time of submittal. The proposed plan or proposed 
    revision shall remain posted until it is approved, withdrawn or denied.
        (b) Following receipt of the proposed plan or proposed revision, 
    the representative of miners may submit timely comments to the district 
    manager, in writing, for consideration during the review process. A 
    copy of these comments shall also be provided to the operator by the 
    district manager upon request.
        (c) (1) The district manager will notify the operator in writing of 
    the approval or denial of approval of a proposed ventilation plan or 
    proposed revision. A copy of this notification will be sent to the 
    representative of miners by the district manager.
        (2) If the district manager denies approval of a proposed plan or 
    revision, the deficiencies of the plan or revision shall be specified 
    in writing and the operator will be provided an opportunity to discuss 
    the deficiencies with the district manager.
        (d) No proposed ventilation plan shall be implemented before it is 
    approved by the district manager. Any intentional change to the 
    ventilation system that alters the main air current or any split of the 
    main air current in a manner that could materially affect the safety 
    and health of the miners, or any change to the information required in 
    Sec. 75.371 shall be submitted to and approved by the district manager 
    before implementation.
        (e) Before implementing an approved ventilation plan or a revision 
    to a ventilation plan, persons affected by the revision shall be 
    instructed by the operator in its provisions.
        (f) The approved ventilation plan and any revisions shall be--
        (1) Provided upon request to the representative of miners by the 
    operator following notification of approval;
        (2) Made available for inspection by the representative of miners; 
    and
        (3) Posted on the mine bulletin board within 1 working day 
    following notification of approval. The approved plan and revisions 
    shall remain posted on the bulletin board for the period that they are 
    in effect.
        (g) The ventilation plan for each mine shall be reviewed every 6 
    months by an authorized representative of the Secretary to assure that 
    it is suitable to current conditions in the mine.
    
    
    Sec. 75.371  Mine ventilation plan; contents.
    
        The mine ventilation plan shall contain the information described 
    below and any additional provisions required by the district manager:
        (a) The mine name, company name, mine identification number, and 
    the name of the individual submitting the plan information.
        (b) Planned main mine fan stoppages, other than those scheduled for 
    testing, maintenance or adjustment, including procedures to be followed 
    during these stoppages and subsequent restarts (see Sec. 75.311(a)) and 
    the type of device to be used for monitoring main mine fan pressure, if 
    other than a pressure recording device (see 75.310(a)(4)).
        (c) Methods of protecting main mine fans and associated components 
    from the forces of an underground explosion if a 15-foot offset from 
    the nearest side of the mine opening is not provided (see 
    Sec. 75.310(a)(6)); and the methods of protecting main mine fans and 
    intake air openings if combustible material will be within 100 feet of 
    the area surrounding the fan or these openings (see Sec. 75.311(f)).
        (d) Persons that will be permitted to enter the mine, the work 
    these persons will do while in the mine, and electric power circuits 
    that will be energized when a back-up fan system is used that does not 
    provide the ventilating quantity provided by the main mine fan (see 
    Sec. 75.311(c)).
        (e) The locations and operating conditions of booster fans 
    installed in anthracite mines (see Sec. 75.302).
        (f) Section and face ventilation systems used, including drawings 
    illustrating how each system is used, and a description of each 
    different dust suppression system used on equipment on working 
    sections.
        (g) Locations where the air quantities must be greater than 3,000 
    cubic feet per minute (see Sec. 75.325(a)(1)).
        (h) In anthracite mines, locations where the air quantities must be 
    greater than 1,500 cubic feet per minute (see Sec. 75.325(e)(1)).
        (i) Working places and working faces other than those where coal is 
    being cut, mined, drilled for blasting or loaded, where a minimum air 
    quantity will be maintained, and the air quantity at those locations 
    (see Sec. 75.325(a)(1)).
        (j) The operating volume of machine mounted dust collectors or 
    diffuser fans, if used (see Sec. 75.325(a)(3)).
        (k) The minimum mean entry air velocity in exhausting face 
    ventilation systems where coal is being cut, mined, drilled for 
    blasting, or loaded, if the velocity will be less than 60 feet per 
    minute. Other working places where coal is not being cut, mined, 
    drilled for blasting or loaded, where at least 60 feet per minute or 
    some other minimum mean entry air velocity will be maintained (see 
    Sec. 75.326).
        (l) The maximum distance if greater than 10 feet from each working 
    face at which face ventilation control devices will be installed (see 
    Sec. 75.330(b)(2)). The working places other than those where coal is 
    being cut, mined, drilled for blasting or loaded, where face 
    ventilation control devices will be used (see Sec. 75.330(b)(1)(ii).
        (m) The volume of air required in the last open crosscut or the 
    quantity of air reaching the pillar line if greater than 9,000 cubic 
    feet per minute (see Sec. 75.325(b)). 
    
    [[Page 9842]]
    
        (n) In anthracite mines, the volume of air required in the last 
    open crosscut or the quantity of air reaching the pillar line if 
    greater than 5,000 cubic feet per minute (see Sec. 75.325(e)(2)).
        (o) Locations where separations of intake and return air courses 
    will be built and maintained to other than the third connecting 
    crosscut outby each working face (see Sec. 75.333(b)(1)).
        (p) The volume of air required at the intake to the longwall 
    sections, if different than 30,000 cubic feet per minute (see 
    Sec. 75.325(c)).
        (q) The velocities of air on a longwall or shortwall face, and the 
    locations where the velocities must be measured (see 
    Sec. 75.325(c)(2)).
        (r) The minimum quantity of air that will be provided during the 
    installation and removal of mechanized mining equipment, the location 
    where this quantity will be provided, and the ventilation controls that 
    will be used. (see Sec. 75.325(d)).
        (s) The locations and frequency of the methane tests if required 
    more often by Sec. 75.362(d)(1)(iii) (see Sec. 75.362 (d)(1)(iii).
        (t) The locations where samples for ``designated areas'' will be 
    collected, including the specific location of each sampling device, and 
    the respirable dust control measures used at the dust generating 
    sources for these locations (see Sec. 70.208 of this chapter).
        (u) The methane and dust control systems at underground dumps, 
    crushers, transfer points, and haulageways.
        (v) Areas in trolley haulage entries where the air velocity will be 
    greater than 250 feet per minute and the velocity in these areas (see 
    Sec. 75.327(b)).
        (w) Locations where entries will be advanced less than 20 feet from 
    the inby rib without a crosscut being provided where a line brattice 
    will be required. (see Sec. 75.333(g)).
        (x) A description of the bleeder system to be used, including its 
    design (see Sec. 75.334).
        (y) The means for determining the effectiveness of bleeder systems 
    (see Sec. 75.334(c)(2)).
        (z) The locations where measurements of methane and oxygen 
    concentrations and air quantities and tests to determine whether the 
    air is moving in the proper direction will be made to evaluate the 
    ventilation of nonpillared worked-out areas (see Sec. 75.364 (a)(1)) 
    and the effectiveness of bleeder systems (see Sec. 75.364 (a)(2)(iii). 
    Alternative methods of evaluation of the effectiveness of bleeder 
    systems (Sec. 75.364 (a)(2)(iv)).
        (aa) The means for adequately maintaining bleeder entries free of 
    obstructions such as roof falls and standing water (see 
    Sec. 75.334(c)(3)).
        (bb) The location of ventilation devices such as regulators, 
    stoppings and bleeder connectors used to control air movement through 
    worked-out areas (see Sec. 75.334(c)(4)). The location and sequence of 
    construction of proposed seals for each worked-out area. (see 
    Sec. 75.334(e)).
        (cc) In mines with a demonstrated history of spontaneous 
    combustion: a description of the measures that will be used to detect 
    methane, carbon monoxide, and oxygen concentration during and after 
    pillar recovery and in worked-out areas where no pillars have been 
    recovered (see Sec. 75.334(f)(1); and, the actions which will be taken 
    to protect miners from the hazards associated with spontaneous 
    combustion (see Sec. 75.334(f)(2). If a bleeder system will not be 
    used, the methods that will be used to control spontaneous combustion, 
    accumulations of methane-air mixtures, and other gases, dusts, and 
    fumes in the worked-out area (see Sec. 75.334(f)(3)).
        (dd) The location of all horizontal degasification holes that are 
    longer than 1,000 feet and the location of all vertical degasification 
    holes.
        (ee) If methane drainage systems are used, a detailed sketch of 
    each system, including a description of safety precautions used with 
    the systems.
        (ff) A description of the methods and materials to be used to seal 
    worked-out areas if those methods or materials will be different from 
    those specified by Sec. 75.335(a)(1).
        (gg) The alternative location for the additional sensing device if 
    the device will not be installed on the longwall shearing machine (see 
    Sec. 75.342(a)(2)).
        (hh) The ambient level in parts per million of carbon monoxide, and 
    the method for determining the ambient level, in all areas where carbon 
    monoxide sensors are installed.
        (ii) The distance that separation between the primary escapeway and 
    the belt or track haulage entries will be maintained if other than to 
    the first connecting crosscut outby the section loading point (see 
    Sec. 75.380(g)).
        (jj) In anthracite mines, the dimensions of escapeways where the 
    pitch of the coal seam does not permit escapeways to be maintained 4 
    feet by 5 feet and the locations where these dimensions must be 
    maintained (see Sec. 75.381(c)(4)).
    
    
    Sec. 75.372  Mine ventilation map.
    
        (a)(1) At intervals not exceeding 12 months, the operator shall 
    submit to the district manager 3 copies of an up-to-date map of the 
    mine drawn to a scale of not less than 100 nor more than 500 feet to 
    the inch. A registered engineer or a registered surveyor shall certify 
    that the map is accurate.
        (2) In addition to the informational requirements of this section 
    the map may also be used to depict and explain plan contents that are 
    required in Sec. 75.371. Information shown on the map to satisfy the 
    requirements of Sec. 75.371 shall be subject to approval by the 
    district manager.
        (b) The map shall contain the following information:
        (1) The mine name, company name, mine identification number, a 
    legend identifying the scale of the map and symbols used, and the name 
    of the individual responsible for the information on the map.
        (2) All areas of the mine, including sealed and unsealed worked-out 
    areas.
        (3) All known mine workings that are located in the same coalbed 
    within 1,000 feet of existing or projected workings. These workings may 
    be shown on a mine map with a scale other than that required by 
    paragraph (a) of this section, if the scale does not exceed 2,000 feet 
    to the inch and is specified on the map.
        (4) The locations of all known mine workings underlying and 
    overlying the mine property and the distance between the mine workings.
        (5) The locations of all known oil and gas wells and all known 
    drill holes that penetrate the coalbed being mined.
        (6) The locations of all main mine fans, installed backup fans and 
    motors, and each fan's specifications, including size, type, model 
    number, manufacturer, operating pressure, motor horsepower, and 
    revolutions per minute.
        (7) The locations of all surface mine openings and the direction 
    and quantity of air at each opening.
        (8) The elevation at the top and bottom of each shaft and slope, 
    and shaft and slope dimensions, including depth and length.
        (9) The direction of air flow in all underground areas of the mine.
        (10) The locations of all active working sections and the four-
    digit identification number for each mechanized mining unit (MMU).
        (11) The location of all escapeways.
        (12) The locations of all ventilation controls, including permanent 
    stoppings, overcasts, undercasts, regulators, seals, airlock doors, 
    haulageway doors and other doors, except temporary ventilation controls 
    on working sections.
        (13) The direction and quantity of air--
        (i) Entering and leaving each split;
        (ii) In the last open crosscut of each set of entries and rooms; 
    and 
    
    [[Page 9843]]
    
        (iii) At the intake end of each pillar line, including any longwall 
    or shortwall.
        (14) Projections for at least 12 months of anticipated mine 
    development, proposed ventilation controls, proposed bleeder systems, 
    and the anticipated location of intake and return air courses, belt 
    entries, and escapeways.
        (15) The locations of existing methane drainage systems.
        (16) The locations of all atmospheric monitoring system sensors.
        (17) Contour lines that pass through whole number elevations of the 
    coalbed being mined. These lines shall be spaced at 10-foot elevation 
    levels unless a wider spacing is permitted by the district manager.
        (18) The location of proposed seals for each worked-out area.
        (19) The entry height, velocity and direction of the air current at 
    or near the midpoint of each belt flight where the height and width of 
    the entry are representative of the belt haulage entry.
        (20) The location and designation of air courses that have been 
    redesignated from intake to return for the purpose of ventilation of 
    structures, areas or installations that are required by this subpart D 
    to be ventilated to return air courses, and for ventilation of seals.
        (c) The mine map required by Sec. 75.1200 may be used to satisfy 
    the requirements for the ventilation map, provided that all the 
    information required by this section is contained on the map.
    
    
    Sec. 75.373  Reopening mines.
    
        After a mine is abandoned or declared inactive, and before it is 
    reopened, mining operations shall not begin until MSHA has been 
    notified and has completed an inspection.
    
    
    Sec. 75.380  Escapeways; bituminous and lignite mines.
    
        (a) Except in situations addressed in Sec. 75.381, Sec. 75.385 and 
    Sec. 75.386, at least two separate and distinct travelable passageways 
    shall be designated as escapeways and shall meet the requirements of 
    this section.
        (b) (1) Escapeways shall be provided from each working section, and 
    each area where mechanized mining equipment is being installed or 
    removed, continuous to the surface escape drift opening or continuous 
    to the escape shaft or slope facilities to the surface.
        (2) During equipment installation, these escapeways shall begin at 
    the projected location for the section loading point. During equipment 
    removal, they shall begin at the location of the last loading point.
        (c) The two separate and distinct escapeways required by this 
    section shall not end at a common shaft, slope, or drift opening, 
    except that multiple compartment shafts or slopes separated by walls 
    constructed of noncombustible material may be used as separate and 
    distinct passageways.
        (d) Each escapeway shall be--
        (1) Maintained in a safe condition to always assure passage of 
    anyone, including disabled persons;
        (2) Clearly marked to show the route and direction of travel to the 
    surface;
        (3) Maintained to at least a height of 5 feet from the mine floor 
    to the mine roof, excluding the thickness of any roof support, except 
    that the escapeways shall be maintained to at least the height of the 
    coalbed, excluding the thickness of any roof support, where the coalbed 
    is less than 5 feet. In areas of mines where escapeways pass through 
    doors, the height may be less than 5 feet, provided that sufficient 
    height is maintained to enable miners, including disabled persons, to 
    escape quickly in an emergency. In areas of mines developed before 
    November 16, 1992, where escapeways pass over or under overcasts or 
    undercasts, the height may be less than 5 feet provided that sufficient 
    height is maintained to enable miners, including disabled persons, to 
    escape quickly in an emergency. When there is a need to determine 
    whether sufficient height is provided, MSHA may require a stretcher 
    test where 4 persons carry a miner through the area in question on a 
    stretcher;
        (4) Maintained at least 6 feet wide except--
        (i) Where necessary supplemental roof support is installed, the 
    escapeway shall not be less than 4 feet wide; or
        (ii) Where the route of travel passes through doors or other 
    permanent ventilation controls, the escapeway shall be at least 4 feet 
    wide to enable miners to escape quickly in an emergency, or
        (iii) Where the alternate escapeway passes through doors or other 
    permanent ventilation controls or where supplemental roof support is 
    required and sufficient width is maintained to enable miners, including 
    disabled persons, to escape quickly in an emergency. When there is a 
    need to determine whether sufficient width is provided, MSHA may 
    require a stretcher test where 4 persons carry a miner through the area 
    in question on a stretcher, or
        (iv) Where mobile equipment near working sections, and other 
    equipment essential to the ongoing operation of longwall sections, is 
    necessary during normal mining operations, such as material cars 
    containing rock dust or roof control supplies, or is to be used for the 
    evacuation of miners off the section in the event of an emergency. In 
    any instance, escapeways shall be of sufficient width to enable miners, 
    including disabled persons, to escape quickly in an emergency. When 
    there is a need to determine whether sufficient width is provided, MSHA 
    may require a stretcher test where 4 persons carry a miner through the 
    area in question on a stretcher;
        (5) Located to follow the most direct, safe and practical route to 
    the nearest mine opening suitable for the safe evacuation of miners; 
    and
        (6) Provided with ladders, stairways, ramps, or similar facilities 
    where the escapeways cross over obstructions.
        (e) Surface openings shall be adequately protected to prevent 
    surface fires, fumes, smoke, and flood water from entering the mine.
        (f) Primary escapeway. (1) One escapeway that is ventilated with 
    intake air shall be designated as the primary escapeway.
        (2) Paragraphs (f)(3) through (f)(7) of this section apply as 
    follows:
        (i) To all areas of a primary escapeway developed on or after 
    November 16, 1992;
        (ii) Effective as of March 11, 1997, to all areas of a primary 
    escapeway developed between March 30, 1970 and November 16, 1992; and
        (iii) Effective as of March 11, 1997, to all areas of the primary 
    escapeway developed prior to March 30, 1970 where separation of the 
    belt and trolley haulage entries from the primary escapeway existed 
    prior to November 16, 1992.
        (3) The following equipment is not permitted in the primary 
    escapeway:
        (i) Unattended operating diesel equipment without an automatic fire 
    suppression system.
        (ii) Mobile equipment hauling coal except for hauling coal 
    incidental to cleanup or maintenance of the primary escapeway.
        (iii) Compressors, except--
        (A) Compressors necessary to maintain the escapeway in safe, 
    travelable condition;
        (B) Compressors that are components of equipment such as 
    locomotives and rock dusting machines; and
        (C) Compressors of less than five horsepower.
        (iv) Underground transformer stations, battery charging stations, 
    substations, and rectifiers except--
        (A) Where necessary to maintain the escapeway in safe, travelable 
    condition; and
        (B) Battery charging stations and rectifiers and power centers with 
    
    
    [[Page 9844]]
    transformers that are either dry-type or contain nonflammable liquid, 
    provided they are located on or near a working section and are moved as 
    the section advances or retreats.
        (v) Water pumps, except--
        (A) Water pumps necessary to maintain the escapeway in safe, 
    travelable condition;
        (B) Submersible pumps;
        (C) Permissible pumps and associated permissible switchgear;
        (D) Pumps located on or near a working section that are moved as 
    the section advances or retreats;
        (E) Pumps installed in anthracite mines; and
        (F) Small portable pumps.
        (4) Mobile equipment operated in the primary escapeway, except for 
    continuous miners and as provided in paragraphs (f)(5), (f)(6), and 
    (f)(7) of this section, shall be equipped with a fire suppression 
    system installed according to Secs. 75.1107-3 through 75.1107-16 that 
    is--
        (i) Manually operated and attended continuously by a person trained 
    in the systems function and use, or
        (ii) A multipurpose dry chemical type capable of both automatic and 
    manual activation.
        (5) Personnel carriers and small mobile equipment designed and used 
    only for carrying people and small hand tools may be operated in 
    primary escapeways if--
        (i) The equipment is provided with a multipurpose dry chemical type 
    fire suppression system capable of both automatic and manual 
    activation, and the suppression system is suitable for the intended 
    application and is listed or approved by a nationally recognized 
    independent testing laboratory, or,
        (ii) Battery powered and provided with two 10 pound multipurpose 
    dry chemical portable fire extinguishers.
        (6) Notwithstanding the requirements of paragraph (f)(3)(i), mobile 
    equipment not provided with a fire suppression system may operate in 
    the primary escapeway if no one is inby except those persons directly 
    engaged in using or moving the equipment.
        (7) Notwithstanding the requirements of paragraph (f)(3)(i), mobile 
    equipment designated and used only as emergency vehicles or ambulances, 
    may be operated in the primary escapeway without fire suppression 
    systems.
        (g) Except where separation of belt and trolley haulage entries 
    from designated escapeways did not exist before November 15, 1992, the 
    primary escapeway shall be separated from belt and trolley haulage 
    entries for its entire length, to and including the first connecting 
    crosscut outby each loading point except when a greater or lesser 
    distance for this separation is specified and approved in the 
    ventilation plan and does not pose a hazard to miners.
        (h) Alternate escapeway. One escapeway shall be designated as the 
    alternate escapeway. The alternate escapeway shall be separated from 
    the primary escapeway for its entire length, except that the alternate 
    and primary escapeways may be ventilated from a common intake air shaft 
    or slope opening.
        (i) Mechanical escape facilities shall be provided and maintained 
    for--
        (1) Each shaft that is part of a designated escapeway and is 
    greater than 50 feet in depth; and
        (2) Each slope from the coal seam to the surface that is part of a 
    designated escapeway and is inclined more than 9 degrees from the 
    horizontal.
        (j) Within 30 minutes after mine personnel on the surface have been 
    notified of an emergency requiring evacuation, mechanical escape 
    facilities provided under paragraph (i) of this section shall be 
    operational at the bottom of shaft and slope openings that are part of 
    escapeways.
        (k) Except where automatically activated hoisting equipment is 
    used, the bottom of each shaft or slope opening that is part of a 
    designated escapeway shall be equipped with a means of signaling a 
    surface location where a person is always on duty when anyone is 
    underground. When the signal is activated or the evacuation of persons 
    underground is necessary, the person shall assure that mechanical 
    escape facilities are operational as required by paragraph (j) of this 
    section.
        (l) (1) Stairways or mechanical escape facilities shall be 
    installed in shafts that are part of the designated escapeways and that 
    are 50 feet or less in depth, except ladders may be used in shafts that 
    are part of the designated escapeways and that are 5 feet or less in 
    depth.
        (2) Stairways shall be constructed of concrete or metal, set on an 
    angle not to exceed 45 degrees from the horizontal, and equipped on the 
    open side with handrails. In addition, landing platforms that are at 
    least 2 feet by 4 feet shall be installed at intervals not to exceed 20 
    vertical feet on the stairways and equipped on the open side with 
    handrails.
        (3) Ladders shall be constructed of metal, anchored securely, and 
    set on an angle not to exceed 60 degrees from the horizontal.
        (m) A travelway designed to prevent slippage shall be provided in 
    slope and drift openings that are part of designated escapeways, unless 
    mechanical escape facilities are installed.
    
    
    Sec. 75.381  Escapeways; anthracite mines.
    
        (a) Except as provided in Secs. 75.385 and 75.386, at least two 
    separate and distinct travelable passageways shall be designated as 
    escapeways and shall meet the requirements of this section.
        (b) Escapeways shall be provided from each working section 
    continuous to the surface.
        (c) Each escapeway shall be--
        (1) Maintained in a safe condition to always assure passage of 
    anyone, including disabled persons;
        (2) Clearly marked to show the route of travel to the surface;
        (3) Provided with ladders, stairways, ramps, or similar facilities 
    where the escapeways cross over obstructions; and
        (4) Maintained at least 4 feet wide by 5 feet high. If the pitch or 
    thickness of the coal seam does not permit these dimensions to be 
    maintained other dimensions may be approved in the ventilation plan.
        (d) Surface openings shall be adequately protected to prevent 
    surface fires, fumes, smoke, and flood water from entering the mine.
        (e) Primary escapeway. One escapeway that shall be ventilated with 
    intake air shall be designated as the primary escapeway.
        (f) Alternate escapeway. One escapeway that shall be designated as 
    the alternate escapeway shall be separated from the primary escapeway 
    for its entire length.
        (g) Mechanical escape facilities shall be provided--
        (1) For each shaft or slope opening that is part of a primary 
    escapeway; and
        (2) For slopes that are part of escapeways, unless ladders are 
    installed.
        (h) Within 30 minutes after mine personnel on the surface have been 
    notified of an emergency requiring evacuation, mechanical escape 
    facilities shall be operational at the bottom of each shaft and slope 
    opening that is part of an escapeway.
        (i) Except where automatically activated hoisting equipment is 
    used, the bottom of each shaft or slope opening that is part of a 
    primary escapeway shall be equipped with a means of signaling a surface 
    location where a person is always on duty when anyone is underground. 
    When the signal is activated or the evacuation of personnel is 
    necessary, the person on duty shall assure that mechanical escape 
    facilities are operational as required by paragraph (h) of this 
    section. 
    
    [[Page 9845]]
    
    
    
    Sec. 75.382  Mechanical escape facilities.
    
        (a) Mechanical escape facilities shall be provided with overspeed, 
    overwind, and automatic stop controls.
        (b) Every mechanical escape facility with a platform, cage, or 
    other device shall be equipped with brakes that can stop the fully 
    loaded platform, cage, or other device.
        (c) Mechanical escape facilities, including automatic elevators, 
    shall be examined weekly. The weekly examination of this equipment may 
    be conducted at the same time as a daily examination required by 
    Sec. 75.1400-3.
        (1) The weekly examination shall include an examination of the 
    headgear, connections, links and chains, overspeed and overwind 
    controls, automatic stop controls, and other facilities.
        (2) At least once each week, the hoist shall be run through one 
    complete cycle of operation to determine that it is operating properly.
        (d) A person trained to operate the mechanical escape facility 
    always shall be available while anyone is underground to provide the 
    mechanical escape facilities, if required, to the bottom of each shaft 
    and slope opening that is part of an escapeway within 30 minutes after 
    personnel on the surface have been notified of an emergency requiring 
    evacuation. However, no operator is required for automatically operated 
    cages, platforms, or elevators.
        (e) Mechanical escape facilities shall have rated capacities 
    consistent with the loads handled.
        (f) Manually-operated mechanical escape facilities shall be 
    equipped with indicators that accurately and reliably show the position 
    of the facility.
        (g) Certification. The person making the examination as required by 
    paragraph (c) of this section shall certify by initials, date, and the 
    time that the examination was made. Certifications shall be made at or 
    near the facility examined.
    
    
    Sec. 75.383  Escapeway maps and drills.
    
        (a) A map shall be posted or readily accessible to all miners in 
    each working section, and in each area where mechanized mining 
    equipment is being installed or removed. The map shall show the 
    designated escapeways from the working section to the location where 
    miners must travel to satisfy the escapeway drill specified in 
    paragraph (b)(1) of this section. A map showing the main escapeways 
    shall be posted at a surface location of the mine where miners 
    congregate, such as at the mine bulletin board, bathhouse, or waiting 
    room. All maps shall be kept up to date, and any changes in route of 
    travel, locations of doors, or directions of airflow shall be shown on 
    the maps by the end of the shift on which the changes are made, and 
    affected miners shall be informed of the changes before entering the 
    underground areas of the mine. Miners underground on a shift when any 
    such change is made shall be immediately notified of the change.
        (b) (1) At least once every 90 days, each miner, including miners 
    with working stations located between working sections and main 
    escapeways, shall participate in a practice escapeway drill. During 
    this drill, each miner shall travel the primary or alternate escapeway 
    from the miner's working section or area where mechanized mining 
    equipment is being installed or removed, to the area where the split of 
    air ventilating the working section intersects a main air course, or 
    2,000 feet outby the section loading point, whichever distance is 
    greater. Other miners shall participate in the escapeway drill by 
    traveling in the primary or alternate escapeway for a distance of 2,000 
    feet from their working station toward the nearest escape facility or 
    drift opening. An escapeway drill shall not be conducted in the same 
    escapeway as the immediately preceding drill.
        (2) At least once every 6 weeks and for each shift, at least two 
    miners on each coal producing working section who work on that section, 
    accompanied by the section supervisor, shall participate in a practice 
    escape drill and shall travel the primary or alternate escapeway from 
    the location specified in paragraph (b)(1) of this section, to the 
    surface, to mechanical escape facilities, or to an underground entrance 
    to a shaft or slope to the surface. Systematic rotation of section 
    personnel shall be used so that all miners participate in this drill. 
    An escapeway drill shall not be conducted in the same escapeway as the 
    immediately preceding drill.
        (3) At least once every 6 weeks, at least two miners on each 
    maintenance shift and a supervisor, shall participate in a practice 
    escape drill and shall travel the primary or alternate escapeway from 
    the location specified in paragraph (b)(1) of this section, to the 
    surface, to mechanical escape facilities, or to an underground entrance 
    to a shaft or slope to the surface. Systematic rotation of maintenance 
    personnel and working sections shall be used so that all miners 
    participate in this drill and the escapeways from all sections are 
    traveled. An escapeway drill shall not be conducted in the same 
    escapeway as the immediately preceding drill.
        (4) Before or during practice escapeway drills, miners shall be 
    informed of the locations of fire doors, check curtains, changes in the 
    routes of travel, and plans for diverting smoke from escapeways.
        (c) The practice escapeway drills may be used to satisfy the 
    evacuation specifications of the fire drills required by Sec. 75.1101-
    23.
    
    
    Sec. 75.384  Longwall and shortwall travelways.
    
        (a) If longwall or shortwall mining systems are used and the two 
    designated escapeways required by Sec. 75.380 are located on the 
    headgate side of the longwall or shortwall, a travelway shall be 
    provided on the tailgate side of that longwall or shortwall. The 
    travelway shall be located to follow the most direct and safe practical 
    route to a designated escapeway.
        (b) The route of travel shall be clearly marked.
        (c) When a roof fall or other blockage occurs that prevents travel 
    in the travelway--
        (1) Work shall cease on the longwall or shortwall face;
        (2) Miners shall be withdrawn from face areas to a safe area outby 
    the section loading point; and
        (3) MSHA shall be notified.
        (d) Work may resume on the longwall or shortwall face after the 
    procedures set out in Secs. 75.215 and 75.222 are implemented.
    
    
    Sec. 75.385  Opening new mines.
    
        When new mines are opened, no more than 20 miners at a time shall 
    be allowed in any mine until a connection has been made between the 
    mine openings, and these connections shall be made as soon as possible.
    
    
    Sec. 75.386  Final mining of pillars.
    
        When only one mine opening is available due to final mining of 
    pillars, no more than 20 miners at a time shall be allowed in the mine, 
    and the distance between the mine opening and working face shall not 
    exceed 500 feet.
    
    
    Sec. 75.388  Boreholes in advance of mining.
    
        (a) Boreholes shall be drilled in each advancing working place when 
    the working place approaches--
        (1) To within 50 feet of any area located in the mine as shown by 
    surveys that are certified by a registered engineer or registered 
    surveyor unless the area has been preshift examined;
        (2) To within 200 feet of any area located in the mine not shown by 
    surveys that are certified by a registered engineer or registered 
    surveyor unless the area has been preshift examined; or
        (3) To within 200 feet of any mine workings of an adjacent mine 
    located in 
    
    [[Page 9846]]
    the same coalbed unless the mine workings have been preshift examined.
        (b) Boreholes shall be drilled as follows:
        (1) Into the working face, parallel to the rib, and within 3 feet 
    of each rib.
        (2) Into the working face, parallel to the rib, and at intervals 
    across the face not to exceed 8 feet.
        (3) At least 20 feet in depth in advance of the working face, and 
    always maintained to a distance of 10 feet in advance of the working 
    face.
        (c) Boreholes shall be drilled in both ribs of advancing working 
    places described in paragraph (a) of this section unless an alternative 
    drilling plan is approved by the District Manager in accordance with 
    paragraph (g) of this section. These boreholes shall be drilled--
        (1) At an angle of 45 degrees to the direction of advance;
        (2) At least 20 feet in depth; and
        (3) At intervals not to exceed 8 feet.
        (d) When a borehole penetrates an area that cannot be examined, and 
    before mining continues, a certified person shall, if possible, 
    determine--
        (1) The direction of airflow in the borehole;
        (2) The pressure differential between the penetrated area and the 
    mine workings;
        (3) The concentrations of methane, oxygen, carbon monoxide, and 
    carbon dioxide; and
        (4) Whether water is impounded within the penetrated area.
        (e) Unless action is taken to dewater or to ventilate penetrated 
    areas, boreholes shall be plugged with wooden plugs or similar devices 
    when--
        (1) Tests conducted at the boreholes show that the atmosphere in 
    the penetrated area contains more than 1.0 percent methane, less than 
    19.5 percent oxygen, or harmful concentrations of carbon monoxide, 
    carbon dioxide or other explosive, harmful or noxious gases;
        (2) Tests for methane, oxygen, carbon monoxide, and carbon dioxide 
    cannot be made because air from mine workings is flowing into the 
    penetrated area; or
        (3) Water is discharging through the boreholes from the penetrated 
    area into the mine workings.
        (f) If mining is to be conducted within 50 feet above or below an 
    inaccessible area of another mine, boreholes shall be drilled, as 
    necessary, according to a plan approved by the district manager.
        (g) Alternative borehole patterns that provide the same protection 
    to miners as the pattern established by paragraphs (b) and (c) of this 
    section may be used under a plan approved by the district manager.
    
    
    Sec. 75.389  Mining into inaccessible areas.
    
        (a) (1) The operator shall develop and follow a plan for mining 
    into areas penetrated by boreholes drilled under Sec. 75.388.
        (2) Mining shall not resume into any area penetrated by boreholes 
    until conditions in the penetrated area can be determined under 
    Sec. 75.388 and the plan for mining-through into the area has been 
    approved by the district manager.
        (3) A copy of the procedures to be followed shall be posted near 
    the site of the mining-through operations and the operator shall 
    explain these procedures to all miners involved in the operations.
        (b) The procedures specified in the plan shall include--
        (1) The method of ventilation, ventilation controls, and the air 
    quantities and velocities in the affected working section and working 
    place;
        (2) Dewatering procedures to be used if a penetrated area contains 
    a water accumulation; and
        (3) The procedures and precautions to be followed during mining-
    through operations.
        (c) Except for routine mining-through operations that are part of a 
    retreat section ventilation system approved in accordance with 
    Sec. 75.371(f) and (x), the following provisions shall apply:
        (1) Before and during mining-through operations, a certified person 
    shall perform air quality tests at intervals and at locations necessary 
    to protect the safety of the miners.
        (2) During mining-through operations, only persons involved in 
    these operations shall be permitted in the mine; and
        (3) After mining-through, a certified person shall determine that 
    the affected areas are safe before any persons enter the underground 
    areas of the mine.
    
    [FR Doc. 96-5453 Filed 3-6-96; 11:23 am]
    BILLING CODE 4510-43-P
    
    

Document Information

Effective Date:
6/10/1996
Published:
03/11/1996
Department:
Mine Safety and Health Administration
Entry Type:
Rule
Action:
Final rule.
Document Number:
96-5453
Dates:
The final rule is effective June 10, 1996.
Pages:
9764-9846 (83 pages)
RINs:
1219-AA11: Underground Coal Mine Ventilation
RIN Links:
https://www.federalregister.gov/regulations/1219-AA11/underground-coal-mine-ventilation
PDF File:
96-5453.pdf
CFR: (80)
30 CFR 75.326)
30 CFR 75.340(a)
30 CFR 75.310(a)(6))
30 CFR 75.342(a)(2))
30 CFR 75.344(a)
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