[Federal Register Volume 59, Number 53 (Friday, March 18, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-4753]
[[Page Unknown]]
[Federal Register: March 18, 1994]
_______________________________________________________________________
Part II
Environmental Protection Agency
_______________________________________________________________________
40 CFR Parts 9 and 82
Protection of Stratospheric Ozone; Final Rule
ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 9 and 82
[FRL-4839-7]
RIN 2060-AD48
Protection of Stratospheric Ozone
AGENCY: Environmental Protection Agency (EPA).
ACTION: Final rule.
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SUMMARY: This final rule promulgates the U.S. Environmental Protection
Agency's (EPA) program for evaluating and regulating substitutes for
ozone-depleting chemicals being phased out under the stratospheric
ozone protection provisions of the Clean Air Act (CAA). In section 612
of the CAA, the Agency is authorized to identify and restrict the use
of substitutes for class I and II ozone-depleting substances where the
Administrator has determined that other alternatives exist that reduce
overall risk to human health and the environment. EPA is referring to
the program that provides these determinations as the Significant New
Alternatives Policy (SNAP) program. The intended effect of this final
rule is to expedite movement away from ozone-depleting compounds by
identifying substitutes that offer lower overall risks to human health
and the environment.
In this final rule, EPA is both issuing decisions on the
acceptability and unacceptability of substitutes and promulgating its
plan for administering the SNAP program. To arrive at determinations on
the acceptability of substitutes, the Agency completed a crossmedia
analysis of risks to human health and the environment from the use of
various substitutes in different industrial end-uses. Results of this
analysis are summarized in this final rule, which covers substitutes in
the following sectors: Refrigeration and air conditioning, foam
blowing, solvents cleaning, fire suppression and explosion protection,
tobacco expansion, adhesives, coatings and inks, aerosols, and
sterilants. Analysis of substitutes in a ninth sector, pesticides, will
be completed, and the resulting decisions will be added to future SNAP
determinations published in the Federal Register. These sectors
comprise the principal United States industrial sectors that
historically consumed large volumes of ozone-depleting compounds.
EFFECTIVE DATE: This rule is effective on April 18, 1994.
ADDRESSES: Materials relevant to the rulemaking are contained in Air
Docket A-91-42, Central Docket Section, South Conference room 4, U.S.
Environmental Protection Agency, 401 M Street SW., Washington, DC
20460. The docket may be inspected between 8 a.m. and 12 noon, and from
1:30 p.m. and 3:30 p.m. on weekdays. As provided in 40 CFR part 2, a
reasonable fee may be charged for photocopying.
Notifications, petitions or other materials required by this final
rule should be sent to: SNAP Coordinator, U.S Environmental Protection
Agency, (6205-J), 401 M Street SW., Washington, DC 20460.
FOR FURTHER INFORMATION CONTACT: The Stratospheric Ozone Information
Hotline at 1-800-296-1996 can be contacted for information on weekdays
from 10 a.m. to 4 p.m. Eastern Time or contact Sally Rand at (202) 233-
9739, Substitutes Analysis and Review Branch, Stratospheric Protection
Division, Office of Atmospheric Programs, Office of Air and Radiation
(6205-J), 401 M Street SW., Washington, DC 20460.
SUPPLEMENTARY INFORMATION: In this preamble, EPA describes the final
SNAP program in sections III through VIII. Although EPA may include
responses to certain comments throughout the description of the
program, readers should see section III.D. for a discussion of EPA's
responses to public comment on major issues. See also the Response to
Comment document found in Docket A-91-42 for a detailed response to
comments on all issues.
I. Overview of Final Rule
This final rule is divided into eleven sections, including this
overview:
I. Overview of Final Rule.
II. Background.
A. Regulatory History.
B. Subgroup of the Federal Advisory Committee.
III. Section 612 Program.
A. Statutory Requirements.
B. Guiding Principles.
C. Implementation Strategy.
D. Response to Public Comment.
IV. Scope of Coverage.
A. Definition of Substitute.
B. Who Must Report.
V. Information Submission.
A. Overview.
B. Information Required.
C. Submission of Confidential Business Information.
D. Display of OMB Control Numbers.
VI. Effective Date of Coverage.
A. General Provisions.
B. Grandfathered Use of Unacceptable Substitutes.
VII. Notice, Review, and Decision-Making Procedures.
A. Substitutes Reviewed under SNAP Only.
B. Joint Review of New Substitutes under SNAP and the Toxic
Substances Control Act Premanufacture Notice (TSCA PMN) Program.
C. Joint Review of Substitutes under SNAP and the Federal
Insecticide, Fungicide, and Rodenticide Act (FIFRA).
D. Shared Statutory Authority with the Food and Drug
Administration (FDA).
VIII. Petitions.
A. Background.
B. Content of the Petition.
C. Sufficiency of Data.
D. Criteria for Evaluating Petitions.
E. Petition Review Process.
IX. Listing of Substitutes.
A. Overview.
B. Format for SNAP Determinations.
C. Decisions Universally Applicable.
D. Refrigeration and Air Conditioning.
E. Foam Blowing.
F. Solvents Cleaning.
G. Fire Suppression and Explosion Protection.
H. Sterilants.
I. Aerosols.
J. Tobacco Expansion.
K. Adhesives, Coatings and Inks.
X. Additional Information.
XI. References.
Appendix A: Class I and Class II Ozone-Depleting Substances.
Appendix B: Summary of Listing Decisions.
Appendix C: Data Confidentiality Claims.
II. Background
A. Regulatory History
The stratospheric ozone layer protects the earth from dangerous
ultraviolet-B (UV-B) radiation. Depletion of stratospheric ozone allows
more UV-B radiation to penetrate to the earth's surface. Increased
radiation, in turn, has been linked to higher incidence of certain skin
cancers and cataracts, suppression of the human immune system, damage
to crops and aquatic organisms, and increased formation of ground-level
ozone. Further, increased radiation can cause economic losses from
materials damage such as more rapid weathering of outdoor plastics.
(See 53 FR 30566 (August 12, 1988) for more information on the effects
of ozone depletion.)
In response to scientific concerns and findings on ozone depletion,
the United States and twenty-three other nations signed the Montreal
Protocol on Substances that Deplete the Ozone Layer on September 16,
1987. The original agreement set forth a timetable for reducing the
production and consumption of specific ozone-depleting substances,
including CFC-11, CFC-12, CFC-113, CFC-114, CFC-115, Halon 1211, Halon
1301, and Halon 2402. EPA implemented the original Protocol through
regulations allocating production and consumption allowances equal to
the total amount of production and consumption granted to the United
States under the Protocol. (See 53 FR 30566.)
The Parties to the Montreal Protocol met in London June 27-29, 1990
to consider amendments to the Protocol. In response to scientific
evidence indicating greater than expected stratospheric ozone
depletion, the Parties agreed to accelerate the phaseout schedules for
the substances already controlled by the Protocol. They also added
phaseout requirements for other ozone-depleting chemicals, including
methyl chloroform, carbon tetrachloride, and other fully-halogenated
chlorofluorocarbons (CFCs).
On November 15, 1990, then-President Bush signed the Clean Air Act
Amendments (CAAA) of 1990. Title VI, section 604 of the amended CAA
requires a phaseout of CFCs, halons, and carbon tetrachloride by 2000,
which is identical to the London Amendments to the Montreal Protocol,
but with more stringent interim reductions. Title VI also differs from
the London Amendments by mandating a faster phaseout of methyl
chloroform (2002 instead of 2005), a restriction on the use of
hydrochlorofluorocarbons (HCFCs) after 2015, and a ban on the
production of HCFCs after 2030. In Title VI, section 602, the CFCs,
halons, carbon tetrachloride, and methyl chloroform are defined as
class I substances; HCFCs are referred to as class II substances.
Appendix A of this final rule lists the class I and class II substances
identified in the CAA.
In addition to the phaseout requirements, Title VI includes
provisions to reduce emissions of class I and II substances to the
``lowest achievable level'' in the refrigeration sector and to maximize
the use of recycling and recovery upon disposal (section 608). It also
requires EPA to ban certain nonessential products containing ozone-
depleting substances (section 610); establish standards and
requirements for the servicing of motor vehicle air conditioners
(section 609); mandate warning labels on products made with or
containing class I or containing class II substances (section 611); and
establish a safe alternatives program (section 612). The development
and implementation of the safe alternatives program under section 612
is the subject of this final rule.
In October 1991, the National Aeronautics and Space Administration
(NASA) announced new findings documenting ozone depletion over the last
decade that was more severe than had previously been predicted by
atmospheric modeling or measurements. In particular, NASA found 2.9
percent ozone depletion over the northern mid-latitudes over the past
decade in summertime--the first time a trend showing ozone depletion
had been detected in the U.S. during that time of year, when risks from
depletion are greatest.
Partly in response to these findings, on February 11, 1992, then-
President Bush announced an accelerated phaseout schedule for class I
substances as identified in the CAA, as amended, section 606. This
final schedule, published in the Federal Register (58 FR 65018;
December 10, 1993), implements a January 1, 1996 phaseout of class I
chemicals. The President also ordered an accelerated review of
substitutes that reduce damage to the ozone layer. The expedited
phaseout schedule and the President's directive regarding alternatives
added urgency to EPA's effort to review and list substitutes for class
I and II substances under section 612.
B. Subgroup of the Federal Advisory Committee
In 1989, EPA organized the Stratospheric Ozone Protection Advisory
Committee (STOPAC) in accordance with the requirements of the Federal
Advisory Committee Act, 5 U.S.C. app. section 9(c). The STOPAC
consisted of members selected on the basis of their professional
qualifications and diversity of perspectives and provided
representation from industry, academia, federal, state, and local
government agencies, non-governmental and environmental groups, as well
as international organizations. The purpose of STOPAC was to provide
advice to the Agency on policy and technical issues related to the
protection of stratospheric ozone.
In 1991, the Agency asked STOPAC members to participate in
subgroups to assist in developing regulations under title VI of the
CAA. EPA established a subgroup of the standing STOPAC to guide the
Agency specifically on development of the safe alternatives program.
The subgroup on safe alternatives met twice. At the first meeting in
May 1991, subgroup members reviewed a detailed description of EPA's
plans for implementing section 612. At this meeting, there was general
agreement on the need to issue a request for data to provide the
general public with an opportunity to furnish the Agency with
information on substitutes. The group also agreed on the need to review
substitutes as quickly as possible to avoid any delay in industry's
efforts to phase out ozone-depleting substances.
At the second meeting of the subgroup, in July 1991, subgroup
members provided EPA with comments on a draft of the Advance Notice of
Proposed Rulemaking (ANPRM), which was prepared in response to the
conclusions of the first meeting. The comments focused primarily on the
draft discussion of EPA's plans for implementing section 612 and
refinements to a list of preliminary substitutes that the Agency
intended to review. Based on comments received from the subgroup and
other offices within EPA, a final ANPRM was prepared and published in
the Federal Register on January 16, 1992 (57 FR 1984). Because the bulk
of regulatory development required under title VI has been completed,
the STOPAC has since been disbanded.
III. Section 612 Program
A. Statutory Requirements
Section 612 of the Clean Air Act authorizes EPA to develop a
program for evaluating alternatives to ozone-depleting substances. EPA
is referring to this new program as the Significant New Alternatives
Policy (SNAP) program. The major provisions of section 612 are:
Rulemaking--Section 612(c) requires EPA to promulgate
rules making it unlawful to replace any class I or class II substance
with any substitute that the Administrator determines may present
adverse effects to human health or the environment where the
Administrator has identified an alternative that (1) reduces the
overall risk to human health and the environment, and (2) is currently
or potentially available.
Listing of Unacceptable/Acceptable Substitutes--Section
612(c) also requires EPA to publish a list of the substitutes
unacceptable for specific uses. EPA must publish a corresponding list
of acceptable alternatives for specific uses.
Petition Process--Section 612(d) grants the right to any
person to petition EPA to add a substance to or delete a substance from
the lists published in accordance with section 612(c). The Agency has
90 days to grant or deny a petition. Where the Agency grants the
petition, EPA must publish the revised lists within an additional 6
months.
90-day Notification--Section 612(e) requires EPA to
require any person who produces a chemical substitute for a class I
substance to notify the Agency not less than 90 days before new or
existing chemicals are introduced into interstate commerce for
significant new uses as substitutes for a class I substance. The
producer must also provide the Agency with the producer's unpublished
health and safety studies on such substitutes.
Outreach--Section 612(b)(1) states that the Administrator
shall seek to maximize the use of federal research facilities and
resources to assist users of class I and II substances in identifying
and developing alternatives to the use of such substances in key
commercial applications.
Clearinghouse--Section 612(b)(4) requires the Agency to
set up a public clearinghouse of alternative chemicals, product
substitutes, and alternative manufacturing processes that are available
for products and manufacturing processes which use class I and II
substances.
B. Guiding Principles
EPA has followed several guiding principles in developing the SNAP
program:
1. Evaluate Substitutes Within a Comparative Risk Framework
The Agency's risk evaluation compares risks of substitutes to risks
from continued use of ozone-depleting compounds as well as to risks
associated with other substitutes. This evaluation considers effects
due to ozone depletion as well as effects due to direct toxicity of
substitutes. Other risk factors considered include effects on water and
air quality, the potential for direct and indirect contributions to
global warming, and occupational health and safety. Any effects found
to pose a concern will be evaluated further to determine if controls
are required. EPA does not believe that a numerical scheme producing a
single index to rank all substitutes based on risks is appropriate. A
strict quantitative index would not allow for sufficient flexibility in
making appropriate risk management decisions that consider issues such
as the quality of information supporting the decision, the degree of
uncertainty in the data, the availability of other substitutes, and
economic feasibility.
2. Do Not Require That Substitutes Be Risk-Free To Be Found Acceptable
Section 612(c) requires the Agency to publish a list of acceptable
and unacceptable substitutes. The Agency interprets this as a mandate
to identify substitutes that reduce risks compared to use of class I or
II compounds or to other substitutes for class I or II substances,
rather than a mandate to list as acceptable only those substitutes with
zero risks. In keeping with this interpretation, the Agency believes
that a key goal of the SNAP program is to promote the use of
substitutes for class I and II chemicals that minimize risks to human
health and the environment relative to other alternatives. In some
cases, this approach may involve designating a substitute acceptable
even though the compound may be toxic, or pose other environmental risk
of some type, provided its use reduces overall risk to human health and
the environment as compared to use of class I or class II substances or
other potential substitutes.
3. Restrict Only Those Substitutes That are Significantly Worse
As a corollary to the above point, EPA does not intend to restrict
a substitute if it poses only marginally greater risk than another
substitute. Drawing fine distinctions concerning the acceptability of
substitutes would be extremely difficult given the variability in how
each substitute can be used within a specific application and the
resulting uncertainties surrounding potential health and environmental
effects. The Agency also does not want to intercede in the market's
choice of available substitutes, unless a substitute has been proposed
or is being used that is clearly more harmful to human health and the
environment than other alternatives.
4. Evaluate Risks by Use
Section 612 requires that substitutes be evaluated by use.
Environmental and human health exposures can vary significantly
depending on the particular application of a substitute. Thus, the risk
characterizations must be designed to represent differences in the
environmental and human health effects associated with diverse uses.
This approach cannot, however, imply fundamental tradeoffs with respect
to different types of risk to either the environment or to human
health. For example, in the Agency's consideration of global warming as
a criterion under SNAP, EPA has principally compared different global
warming gases among themselves, as opposed to attempting to establish
some methodology for comparing directly the effects of global warming
and ozone depletion.
5. Provide the Regulated Community With Information as Soon as Possible
The Agency recognizes the need to provide the regulated community
with information on the acceptability of various substitutes as soon as
possible. Given this need, EPA has decided to expedite the review
process by conducting initial risk screens for the major substitutes
now known to the Agency and to include them in this final rulemaking.
Future determinations on the acceptability of new substitutes will be
published in quarterly updates to the SNAP lists.
6. Do Not Endorse Products Manufactured by Specific Companies
While the goal of the SNAP program is to identify acceptable
substitutes, the Agency will not issue company-specific product
endorsements. In many cases, the Agency may base its analysis on data
received on individual products, but the addition of a substitute to
the acceptable list based on that analysis does not represent
endorsement of that company's products. Generally, placement on the
list merely constitutes an acknowledgement that a particular product
made by a company has been found to be acceptable under SNAP.
7. Defer to Other Environmental Regulations When Warranted
In some cases, EPA and other federal agencies have developed
extensive regulations under other statutes or other parts of the CAA
that address any potential cross- or inter-media transfers that may
result from the use of alternatives to class I and II substances. For
example, ceasing to use an ozone-depleting compound may in some cases
entail increased use of chemicals that contribute to tropospheric air
pollution. These chemicals, such as volatile organic compounds (VOCs)
or hazardous air pollutants (HAPs), are already regulated under other
sections of the CAA, and determinations under the SNAP program will
take these existing regulations into account. Where necessary, the
Office of Air and Radiation will confer with other EPA program offices
or federal agencies to ensure that any regulatory overlap is handled
efficiently.
C. Implementation Strategy
Implementation of the SNAP program is directed towards fulfilling
the general policy contained in section 612 of identifying substitutes
that can serve as replacements for ozone depleting substances,
evaluating their effects on human health and the environment, and
encouraging the use of those substitutes believed to present lower
overall risks relative both to the ozone depleting compounds being
replaced and to other substitutes available for the same end-use.
Implementation of this policy involves four key activities. The first
is to develop, promulgate, and administer a regulatory program for
identifying and evaluating substitutes. The second activity is to
undertake a review of the existing substitutes based on criteria
established for the program and then to publish a list of acceptable
and unacceptable substitutes by application. The third activity is to
review additional substitutes as they are developed to allow their
timely introduction into the marketplace. The fourth is to aggressively
disseminate information about those substitutes found to pose lower
overall risk through a clearinghouse and outreach program.
To expedite implementation of the SNAP program, EPA has not only
developed a screening process for examining the alternatives, as
discussed in this final rule, but has also completed an analysis of
many key substitutes based on the criteria presented here. Section IX
summarizes the results of this assessment. More detail on the steps
leading up to this final rule and the implementation of the SNAP
program is given below.
1. ANPRM and Request for Data
On January 16, 1992, EPA published in the Federal Register an
Advance Notice of Proposed Rulemaking (ANPRM) and Request for Data (57
FR 1984). The ANPRM described in general terms EPA's plans for
developing the SNAP program and solicited public comment on the
Agency's planned approach. The ANPRM also included an appendix listing
substitutes that the Agency planned to include in its initial
substitute determinations. The ANPRM invited industry to submit
information on these substitutes and to identify additional
alternatives to be considered in the SNAP program. The Agency received
approximately one hundred comments from industry, trade groups, and
other federal agencies. These comments contained information on
potential substitutes for ozone-depleting chemicals, as well as
comments on the SNAP program as described in the ANPRM.
2. Notice of Proposed Rulemaking on SNAP Process and Proposed
Determinations
On May 12, 1993 EPA published in the Federal Register a Notice of
Proposed Rulemaking (NPRM) for SNAP (58 FR 28094). The NPRM described
the proposed structure and process for administering the SNAP program
and proposed determinations on the acceptability of key substitutes.
The Notice also contained the proposed regulatory language that would
serve as the legal basis for administering and enforcing the SNAP
program.
In the NPRM, EPA recognized that notice-and-comment rulemaking
procedures were necessary to establish regulations governing SNAP. EPA
further concluded that rulemaking was required to place any substance
on the list of unacceptable substances, to list a substance as
acceptable only with certain use restrictions, or to remove a substance
from either the list of unacceptable or acceptable substitutes. EPA did
not believe, however, that rulemaking procedures were required to list
alternatives as acceptable with no restrictions. Such listings would
not impose any sanction, nor remove any prior license to use a
substance.
3. Final Rulemaking
This final rule promulgates the SNAP process and the first set of
determinations on SNAP substitutes. The Agency may revise these
decisions in the future as it reviews additional substitutes and
receives more data on substitutes already covered by the program.
However, EPA expects future changes to the SNAP lists to be minor, and
thus not to represent an undue burden on the regulated community. The
principal changes the Agency expects to make in the future are to add
new substitutes or sectors to the lists, rather than to change a
substitute's acceptability. Further, once a substitute has been placed
on either the acceptable or the unacceptable list, EPA will conduct
notice-and-comment rulemaking to subsequently remove a substitute from
either list, as described below in section VII. This final rule also
addresses comments that the Agency received on the NPRM, and
incorporates further data on substitutes received during the comment
period.
4. Updates of SNAP Determinations
Three mechanisms exist for revising or expanding the list of SNAP
determinations published in this final regulation. First, under section
612(d), the Agency will review and either grant or deny petitions to
add or delete substances from the SNAP list of acceptable or
unacceptable alternatives. Section VIII of this final rule presents
EPA's method for handling petitions.
The second means of revising or expanding the list of SNAP
determinations is through the notifications, described below, which
must be submitted to EPA 90 days before introduction of a substitute
into interstate commerce for significant new use as an alternative to a
class I or class II substance. These 90-day notifications are required
by section 612(e) of the CAA for producers of alternatives to class I
substances for new uses and by EPA regulations issued under sections
114 and 301 of the Act to implement section 612(c) in all other cases.
Section VII of this final rule discusses the Agency's approach for
processing these notifications, including a strategy for integrating
SNAP notifications with other chemical review programs already being
implemented by EPA under authorities provided in the Toxic Substances
Control Act (TSCA) and the Federal Insecticide, Fungicide, and
Rodenticide Act (FIFRA). Other parts of this final rule also explain
how the Agency addresses the overlap between SNAP regulations and
regulations issued under other titles of the CAA.
Finally, the Agency believes that section 612 authorizes it to
initiate changes to the SNAP determinations independent of any
petitions or notifications received. These amendments can be based on
new data on either additional substitutes or on characteristics of
substitutes previously reviewed.
5. Outreach and Substitute Clearinghouse
Public outreach and the substitute information clearinghouse
comprise the technical assistance component of the SNAP program. The
purpose of this effort is to provide information for the public to use
in selecting acceptable substitutes. Sections VII.A.3.f. and VII.A.3.g
describe the Agency's approach for establishing the clearinghouse and
performing outreach.
D. Response to Public Comment
A document summarizing public comment on the NPRM in greater detail
is available in the public docket supporting this final rule. The major
programmatic issues raised by the commenters and the Agency's response
to them are described below. Major comments specific to the eight SNAP
industry sectors are addressed in sections IX.D. through IX.K. of this
final rule.
1. Scope of the SNAP Rule
a. Class II substances. One commenter supported EPA's position that
the Agency has the authority to review class II substances under SNAP,
particularly EPA's view that where little reduction in ozone depletion
potential (ODP) can be gained in going from a class I substance to a
class II substance, such as from methyl chloroform to HCFC-141b, the
substitution should be disallowed under SNAP. Other commenters
criticized this position, arguing that the omission of any reference to
class II substitutes in section 612(e) clearly indicated Congressional
intent that class II substitutes not be subject to the SNAP program.
For this final rule, the Agency is including class II substances
under the scope of SNAP. The Agency disagrees with one commenter's
interpretation of the limitation in section 612(e). Section 612(c)
specifically mandates that the Agency list unacceptable and acceptable
alternatives for class I or II substances. In addition, the Agency
believes that Congressional intent under section 612 is to reduce the
overall risk from the continued use of ozone depleting substances
(ODSs). The class II substances range in ozone depletion potential
(ODP) from 0.11 for HCFC-141b to 0.02 for HCFC-123. In the evaluation
of substitutes completed for the NPRM, use of some class II substitutes
up to the time of their phaseout was identified as representing
significantly greater overall risk than use of other alternatives
available for a number of end-uses. Consequently, the Agency believes
lower overall risk to human health and the environment can be achieved
by including class II substitutes in SNAP. Despite the limitation in
section 612(e) to producers of class I substances, EPA believes it has
authority under section 114 and section 301(a) to require submission of
SNAP notifications with respect to class II substances as necessary to
enable EPA to carry out its obligation under section 612 to evaluate
both class I and class II substances, as explained in the NPRM.
b. Review of existing versus new substitutes. A number of
commenters believed that EPA's SNAP program has no authority to
restrict existing substitutes, which companies may have switched to in
an effort to eliminate the use of CFCs prior to the publication of this
final rule. Arguments in support of this position include the
prospective language of the statute, which says EPA must make it
``unlawful to replace'' an ODS with a substitute deemed unacceptable.
Many of these commenters recommended grandfathering of these existing
uses, so as not to disrupt industry's transition away from ODSs. An
extension of this concern appears in several comments, in which
commenters expressed the fear that SNAP will revisit prior decisions,
removing substitutes previously deemed acceptable as newer and more
environmentally benign substitutes are developed.
Under the Agency's interpretation of section 612, in order to
fulfill the Congressional mandate to review ``any'' substitute
substance that may present adverse effects to human health and the
environment, both new and existing substitutes must be included under
SNAP. In addition, section 612(e) specifically requires notifying the
Agency before new or existing chemicals are introduced into interstate
commerce. EPA believes that class I and II substances are ``replaced''
within the meaning of section 612(c) each time a substitute is used, so
that once EPA identifies an unacceptable substitute, any future use of
such substitute is prohibited. Under any other interpretation, EPA
could never effectively prohibit the use of any substitute, as some
user could always start to use it prior to EPA's completion of the
rulemaking required to list it as unacceptable. EPA believes Congress
could not have intended such a result, and must therefore have intended
to cover future use of existing substitutes.
c. Grandfathering in SNAP. Many commenters supported the idea of
grandfathering uses of existing substitutes, but felt that the
grandfathering should be broadened to include existing uses of all
substitutes which companies have invested in prior to the promulgation
of the SNAP final rule, and not just HCFC-141b as proposed in the NPRM.
Commenters argued that not doing so would delay transition by creating
uncertainty about the useful life of alternatives.
One commenter argued that the grandfathering scheme EPA has
proposed with respect to HCFC-141b should be extended to existing uses
of perfluorocarbons (PFCs). The commenter notes that title VI calls for
regulation and elimination of ozone-depleting substances while in the
commenter's opinion precluding regulation based on global warming
potential. Since PFCs have no ozone depletion potential, the commenter
argued that they are a better candidate than HCFC-141b for
grandfathering. One commenter proposed two years past the date of an
unacceptability determination as the general grandfathering period.
In this final rule, the Agency will not grandfather existing uses
except in specifically identified cases. The grandfathering provisions
under SNAP do give the Agency flexibility to address unacceptable
listings that might disrupt industry's transition away from ODSs. For
this final rule, the Agency was not presented with significant evidence
from the public comments to believe universal grandfathering of
existing substitutes is warranted. The Agency believes that given the
diversity of the industries covered under the SNAP program, a case-by-
case review of applications using the banned substitute would be
necessary to protect human health and the environment. Moreover, EPA
must be able to justify any grandfathering on a case-by-case basis
under the grandfathering criteria established in the Sierra Club case,
as described below in section VI.B.
In the case of HCFC-141b, the Agency has elected to maintain the
proposed grandfathering period for existing uses, since many users
switched to HCFC-141b when it was believed to offer sufficient risk
reduction. In comparison, for perfluorocarbons, the Agency has made
clear from the beginning of their suggested use as substitutes that the
Agency has concerns about the global warming potential of these
chemicals. EPA believes, therefore, that an extended grandfathering
period in this case is not warranted.
However, the Agency agrees to grandfather for use, existing
supplies of a substitute in the possession of an end-user as of March
18, 1994. Therefore, persons who transitioned to a substitute for an
end-use prior to this final rule may continue use of all existing
supplies of the substitute purchased prior to March 18, 1994 until that
supply is exhausted. As of the effective date of this final rule, only
substitutes purchased prior to March 18, 1994 can be used. Under the
four-part test to judge the appropriateness of grandfathering (see
section VI.B of this final rule), the Agency determined that, on
balance, the results of this test favors this action.
Existing inventory of final products manufactured with or
containing a substitute designated unacceptable as a result of final
EPA rule-making within an end-use covered under SNAP could
theoretically be legally sold after listing. Producers should be aware,
however, that they will be effectively barred from selling a substitute
for use once it has been deemed unacceptable under SNAP, because
potential purchasers will not be able to use it. After the effective
date of this final rule, users will not be able to use any additional
supply of a banned substitute purchased after the publication date of
the unacceptable listing.
d. Exemption for small sectors and small volume uses. In the NPRM,
EPA proposed to exempt small volume use applications requiring less
than 10,000 pounds per year of an ODS substitute from SNAP review. This
proposal generated substantial confusion. Many commenters pointed out
that the 10,000 pounds exemption from reporting and review under SNAP
was vague, and asked for additional clarification. Specifically,
commenters asked whether EPA intended the 10,000 pound limit to apply
at the process, plant, company, or sector level. If applied at the
sector level, some commenters noted that an individual end-user might
have enormous difficulty compiling volume information related to the
behavior of an entire industry sector.
In response to these comments, EPA has decided to maintain the
small use exemption but provide the needed additional clarification of
the Agency's intent. The Agency will exempt from the section 612(e)
notification requirements substitutes used in quantities of 10,000
pounds or less per year within a major industrial sector covered under
SNAP. The responsibility for reporting under the notification
requirement for SNAP falls on those introducing substitutes into
interstate commerce, not on the individual end-user. Similarly, relief
from reporting, if within the bounds of the small use and sector
exemption as defined, rests with the same person.
The Agency believes the burden of responsibility for determining
whether use of a substitute will be small should reside at the same
level as the notification requirement. That is, it should be the
responsibility of the introducing agent to determine whether use of a
particular substitute in a given sector is likely to remain below
10,000 pounds per year. The Agency continues to believe that focusing
the listing decisions on the substitutes sold in the largest volumes
will allow the Agency to target its regulatory efforts to those
applications that offer the maximum risk reduction potential.
Many commenters generally supported EPA's exemption for small
industrial sectors, arguing that the administrative burden imposed by a
SNAP review of all possible substitutions is unjustified by the likely
risks posed by these uses. For this final rule, the Agency will
continue to exempt small sectors and small volume uses within major
industrial sectors from reporting responsibilities under SNAP.
e. Designation of submitters/reporting responsibilities. Many of
the public comments on the NPRM expressed general support for the
flexibility of the reporting requirements, noting it is sensible to
require notification from the person most suited to have the relevant
information. However, some confusion has arisen as to the
implementation and enforcement of these requirements.
The Agency agrees with public comment that the designation of
submitters or reporting responsibility needed clarification in this
final rule. For this final rule then, reporting responsibility rests
with the person who introduced the substitute into interstate commerce
in its final form. As such, the producer could potentially be a
manufacturer, formulator, or an end-user. Identification of designated
submitters is further detailed in section IV.B.
f. Exemption for second-generation substitutes. Many commenters
supported EPA's exemption for second-generation substitutes. However,
several asked for clarification of regulatory language setting out this
exemption. They note that the definition left plenty of room for
advances in the science to calculate increasingly small contributions
to ozone depletion added by hitherto unsuspected compounds, thereby
constantly broadening the scope of SNAP as new concerns develop. They
ask that EPA clarify that SNAP should only apply to substitutes for
class I or class II compounds.
EPA agrees with these comments and has clarified in section
IV.A.2.f. that the definition of second-generation applies only to
substitutes for class I or class II compounds in this final rule.
2. SNAP Determination and Listing Process
a. Allowing for assured minimum periods of use. Numerous commenters
expressed a need for a minimum assured time period of use for
acceptable substitutes in order to facilitate the fastest possible
transition away from class I substances. Some commenters suggested that
this assured minimum period should be established based on some
economic measure, such as the lifetime of equipment in which the
compound is to be used, or the overall payback period for investment in
modifications to allow the use of a transitional compound. One
commenter suggested the use of risk analysis to define the assured
minimum period. Other commenters suggested 10 years as the appropriate
period.
The Agency believes Congress enacted provisions under section 612
which make a minimum assured time period for use of a substitute
neither authorized nor necessary under SNAP. As described in section
VIII of this final rule, a petition under section 612(d) to change a
listing from acceptable to unacceptable or vice versa must include
adequate data. In addition, any change will be formally promulgated as
a rulemaking, which requires EPA to propose, take public comment, and
complete final action for any decision. If the decision is made to
change a listing for a substitute from acceptable to unacceptable, the
grandfathering provisions of this final rule provide the Agency with
the flexibility in appropriate cases to provide time after a substitute
is removed from the list of acceptable substitutes to allow persons who
are then using the substance, or who have expended considerable efforts
in good faith toward its use, to find a different substitute and
recover their investment in prior substitutes.
3. SNAP Information Form
a. Use of global warming potential. Some commenters argue that EPA
has no legal authority under section 612 to regulate substitutes based
on global warming. One commenter noted that during the development of
title VI, Congress deliberately excised global warming from the
statute, and that legislative history of title VI thus argues against
reliance on global warming as a regulatory criterion under SNAP.
Finally, a commenter asserted that not only the Congress, but the
President also believes that ozone depletion and global warming should
be treated separately.
The Agency believes that the Congressional mandate to evaluate
substitutes based on reducing overall risk to human health and the
environment authorizes use of global warming as one of the SNAP
evaluation criteria. Public comment failed to identify any definition
of overall risk that warranted excluding global warming. Further, in
October 1993, the President directed EPA through the Climate Change
Action Plan (CCAP) to use its authority under section 612 of the Clean
Air Act to narrow the uses allowed for hydrofluorocarbons and
perfluorocarbons with high global warming potential.
EPA disagrees with the statutory and legislative history arguments
raised by the commenter. The commenter points to language that relates
only to the listing of ozone depleting and global warming substances,
which is not relevant to EPA's authority under section 612(c) to
regulate substitutes based on an assessment of overall risk. The fact
that Congress may have deleted authority for EPA to phase out use of
substances based solely on their global warming potential without
regard to available substitutes certainly imposes no limitation on
consideration of global warming potential as a factor in assessing the
overall risk of using any class I or II substitute. Especially in light
of President Clinton's recent commitment to use section 612 authority
specifically to narrow uses of high global warming potential CFC
substitutes based on an overall risk assessment, EPA has concluded that
it is appropriate to consider global warming potential as one factor in
the SNAP analysis. Therefore, in this final rule, the Agency will
continue to exercise its statutory authority to review substitutes for
listing as unacceptable or acceptable alternatives, using the criteria
for evaluation set out in the NPRM, including global warming.
4. Definitions
a. Definition of potentially available. Several commenters
supported EPA's definition of potentially available because it would
speed the review process and encourage innovation in development of new
substitutes. Other commenters expressed the concern that EPA's
definition of ``potentially available'' could allow EPA to review and
accept a substitute which may be several years from general commercial
availability, and on that basis to ban some other commonly used
chemical with relatively higher risk. These commenters argued that EPA
should at least wait until test marketing has begun to consider an
alternative ``potentially available'' for the purpose of SNAP review.
Another commenter argued that a knowledge of the economic viability of
a substitute is crucial in assessing its potential availability as a
substitute under SNAP.
Under section 612(c) of the CAA, the Agency is specifically
required to identify alternatives that are either ``currently or
potentially available.'' For this final rule, the Agency is defining as
potentially available any alternative for which adequate health,
safety, and environmental data, as required for the SNAP notification
process, exist to make a determination of acceptability, and which the
Agency reasonably believes to be technically feasible, even if not all
testing has yet been completed and the alternative is not yet produced
or sold. EPA would not prohibit use of a substitute where no substitute
that reduces overall risk is currently available, to avoid situations
where the only available substitute to allow transition away from
ozone-depleting compounds is unacceptable under SNAP.
b. Definition of a substitute. Several commenters expressed support
for EPA's definition of a substitute as used in the NPRM. One commenter
proposed the use of the word ``alternative'' instead of ``substitute,''
while supporting the Agency's general construction of the statute to
allow SNAP's purview to extend beyond chemical substitutes to a broader
range of alternative technologies, including process changes. Another
commenter, while also generally supporting EPA's definition of a
substitute, pointed out that the language ``could replace'' is overly
broad. This commenter noted that this language suggests that someone
who is not using a compound as an ODS replacement, but is aware that it
could be used in this way, should report to EPA under SNAP.
For the purpose of this final rule the Agency is using the word
``substitute'' as a synonym for alternative. As discussed in section
IV.A, this definition includes chemical substitutes, alternative
manufacturing processes, and alternative technologies. In response to
the public comment described above, the Agency has also clarified in
this final rule that SNAP addresses only those substitutes or
alternatives actually replacing the class I and II compounds listed
under section 602 of the CAA within the eight industrial sectors
identified in sections IX.D. through K.
5. General Comments on Substitutes
a. Perfluorocarbons. Under the NPRM for SNAP, EPA proposed
perfluorocarbons (PFCs) as acceptable for limited use as replacements
for ozone depleting chemicals in the solvent cleaning, and fire
suppression and explosion protection sectors. Several commenters
supported the Agency's cautious approach toward PFCs, given the high
global warming potential of these compounds as well as their extreme
atmospheric persistence. Other commenters sought clarification with
respect to the scope of the Agency's proposed restrictions on PFCs.
PFCs are fully fluorinated compounds, unlike CFCs, HCFCs, or
hydrofluorocarbons (HFCs). These chemicals are nonflammable, have low
toxicity, are exempt from federal VOC regulations, and do not
contribute to stratospheric ozone depletion. The environmental
characteristics of concern for these compounds are high global warming
potential (5,000-10,000 times greater than CO2) and long
atmospheric lifetimes (3,000-5,000 years). Although the actual
contributions to global warming depend upon the quantities emitted,
because of their long atmospheric lifetimes, the warming effects of
PFCs are essentially irreversible.
In the proposed rule, EPA identified specific solvent cleaning
applications for which PFCs were acceptable. In response to public
comment seeking clarification of these limitations, EPA is finding PFC
use acceptable in electronics and precision cleaning for only high-
performance, precision-engineered applications where no other
substitute for CFC-113 or MCF would meet performance or safety
requirements. Additional detail on PFC use in the solvent cleaning
sector can be found in section IX.F.
In this final rule, EPA has also clarified the limitations placed
in its proposed rule on the use of PFCs to replace halons. PFC-410
(C4F10) and PFC-614 (C6F14) will be limited to fire
suppression and explosion protection applications where other
alternatives are not technically feasible to meet safety or performance
requirements due to the physical or chemical properties of the agent,
or where human exposure to the extinguishing agent may approach
cardiosensitization levels or result in other unacceptable health
effects under normal operating conditions. Additional detail on PFC use
in the fire suppression and explosion protection sector can be found in
section IX.G.
Before replacing ozone-depleting compounds with PFCs, users must
first investigate whether other alternatives would meet performance or
safety standards. This may include contacting vendors or testing using
other substitutes and equipment. Although special forms or reporting to
EPA is not required, companies must maintain documentation of the
review of alternatives on file. Where users must rely on PFCs for lack
of other options, they should make every effort to adopt closed systems
and recover, recycle and destroy the chemicals where possible. EPA also
encourages PFC users to reduce emissions to a minimum through
conservation practices that address idling losses and operator
variables. Above all, PFC users should continue the search for long-
term alternatives.
IV. Scope of Coverage
A. Definition of Substitute
1. Statutory Language
Based on the language of section 612(a) of the CAA, the Agency
defines within the SNAP program a ``substitute'' as any chemical,
product substitute, or alternative manufacturing process, existing or
new, that could replace a class I or II substance. While subsequent
subsections of section 612 refer only to ``substitute substances'' or
``substitute chemicals,'' EPA interprets these provisions for purposes
of the SNAP program as incorporating the general definition of
substitute presented in section 612(a). The Agency believes that this
definition is consistent with the overall intent of section 612 and is
necessary to enable EPA to identify and analyze the universe of
substitutes for class I and II substances.
Section 612(c) prohibits users from replacing class I or II
substances with any substitute substance which the Administrator
determines may present adverse effects to human health and the
environment, where the Administrator has identified an alternative to
such replacement that: (1) Reduces overall risk to human health and the
environment, and (2) is currently or potentially available. EPA
believes that in addition to authorizing the Agency to ban the use of a
given substitute substance where other alternatives exist, section 612
confers the legal authority to allow the use of a substance only with
certain restrictions--conditions of use or narrowed use limits--while
banning its use otherwise. This authority is inherent in the
Administrator's authority to totally ban use of the substitute where
other acceptable alternatives exist that reduce overall risk. EPA only
intends to use this authority where a viable substitute exists that
would otherwise have to be disallowed because of risk associated with
its uncontrolled use.
a. Use conditions. In imposing conditions on use, EPA does not
intend to preempt other regulatory authorities, such as those exercised
by the Occupational Safety and Health Administration (OSHA) or other
government or industrial standard-setting bodies. Rather, EPA hopes to
fill existing regulatory gaps during the interim period of substitution
away from ozone-depleting compounds and provide the needed margin of
protection to human health and the environment until other regulatory
controls or standards are developed under appropriate authorities.
EPA anticipates applying use conditions only in the rare instances
where clear regulatory gaps exist, and where an unreasonable risk would
exist in the absence of any condition. These restrictions will remain
in place only until the appropriate standard-setting agency acts. Where
appropriate, EPA's use conditions will terminate by their own terms
once the appropriate standard-setting Agency takes action. The
mechanism for informing the public of this change will be the quarterly
Federal Register notices updating the status of the SNAP lists. These
are discussed further in Section VII.A below.
b. Narrowed use limits. In imposing narrowed use limits, the Agency
has sought to expand the list of alternatives available to all
applications within a sector end-use category. EPA recognizes that
certain sector end-uses encompass a broad range of applications,
manufacturing processes, and products. Where EPA narrows uses, a
substitute will be acceptable for use only in certain applications, as
where other alternatives are not technically feasible due to
performance or safety requirements. Conditions on use discussed in
section IV.A.1.a. above refer to how (under what operating conditions)
an otherwise unacceptable substitute may be used; narrowed use limits
define where (in which end-uses and applications) an otherwise
unacceptable substitute may be used.
c. Potentially available. Section 612(e) makes clear that a
chemical can be a substitute whether it is existing or new. Also, the
language in section 612(c) clearly states that a new substitute may be
currently or potentially available. In this final rule, the Agency is
defining as potentially available any alternative for which adequate
information exists to make a determination of acceptability, and which
the Agency reasonably believes to be technically feasible, even if not
all testing has yet been completed and the substitute is not yet
produced and sold.
2. Additional Clarification
EPA believes that the statutory language included in section 612 is
written broadly to allow for a reasonably comprehensive evaluation of
substitutes that will be introduced as replacements for ozone-depleting
chemicals. However, additional clarification is presented below to
further explain the Agency's definition of a ``substitute'' in specific
circumstances based on section 612.
a. Chemicals already listed under TSCA. Section 612(e) explicitly
requires producers of chemicals, both new and existing, to notify the
Agency before introducing such chemicals into interstate commerce for
significant new uses as class I alternatives. In addition, section
612(c) requires the Agency to produce lists of acceptable and
unacceptable substitutes, without regard to the status of each chemical
alternative, whether new or existing.
These interrelated provisions of section 612 serve as the basis for
the Agency's belief that all substitutes, whether ``new or existing''
chemicals, should be subject to SNAP review. This regulatory purview
would thus necessarily extend to those chemicals already listed on the
TSCA inventory of existing chemicals. EPA believes SNAP review is
critical for such chemicals given the differing statutory objectives of
TSCA and the CAA, and the new and expanded applications of many
existing chemicals as class I and II replacements, which could alter
existing release and exposure profiles.
b. Significant new use of existing alternatives. There has also
been some question regarding whether an existing alternative already
being sold commercially within a SNAP sector (e.g., use of semi-aqueous
cleaners in the electronics industry) would be subject to review under
section 612. The Agency believes that it should be subject to review
under SNAP. Because of the phaseout, uses of existing substitutes can
reasonably be expected to increase significantly beyond current
consumption, which could translate into greater releases and risks from
use of a substitute. Existing substitutes are therefore subject to SNAP
review because EPA believes that their use can be expected to
significantly expand to new users or product lines. Users should note
that the SNAP determinations discussed in section IX of this final rule
demonstrate that with few exceptions, all substitutes already on the
market meet the conditions for acceptability under the SNAP program.
c. Authority to review substitutes for class II compounds. Section
612(c) authorizes the Administrator to prohibit the use of substitutes
for class II, as well as class I substances, and requires the Agency to
compile lists of substitutes for class II as well as class I compounds
upon making the requisite findings. EPA believes that this is in part
because of the considerable overlap in sectors that use class I and II
substances. More importantly, this mirrors the statute's general
emphasis on moving away from class I compounds in a way that does not
create new and unintended environmental problems. Clearly, for the same
reasons class I substitutes require review under the SNAP program,
class II substitutes should also be reviewed.
To obtain the data necessary to analyze class II substitutes, the
Agency is using statutory authority provided in sections 114 and 301 of
the CAA in conjunction with 612(c). As explained in the NPRM, these
sections, when read together, authorize the Administrator to promulgate
such regulations as needed to require companies to provide information
EPA may reasonably need to identify acceptable and unacceptable
substitutes for class II substances. EPA is exercising this authority
to subject class I and II substitutes to the same information reporting
requirements and listing process.
d. Designation of class I and II chemicals as substitutes. EPA
believes that review authority under section 612 extends also to use of
class I and II chemicals as substitutes, even though these chemicals
are subject to the phaseout provisions of the CAA. While one comment
received by the Agency in response to the NPRM questions EPA's
authority under section 612 to review class I and II chemicals as
substitutes (e.g., methyl chloroform used to replace CFC-113), it is
clear that these compounds can be used as substitutes for other class I
and II substances in certain applications. Since section 612 authority
extends to ``any'' substitutes, both class I and II substances are
subject to review under the SNAP program just as any other substitute.
Given the potential for the class I and II chemicals used as
substitutes for other ozone-depleting chemicals to continue depleting
stratospheric ozone and thus affect human health and the environment, a
close examination of these alternatives in the context of both their
effect on the environment and the availability of other substitutes for
particular uses is especially warranted under section 612.
e. Alternative products and manufacturing processes. EPA believes
that section 612(c) broadly charges EPA to identify alternatives to
ozone-depleting substances. For example, EPA believes that alternative
products can include no-clean fluxes in electronics manufacturing
processes that currently use class I or II compounds as cleaning
solvents. EPA believes it appropriate to consider substitute processes
and products for review under the SNAP program, since many of these
alternatives are viable substitutes and could reduce overall risks to
human health and the environment. EPA believes that such alternative
products and processes, therefore, fall within the definition of
substitutes under section 612.
Similarly, new production techniques and/or processing equipment
are important developments that can minimize environmental releases.
Accordingly, alternative manufacturing processes will also be examined
under section 612 in the context of use and emissions of substitutes.
EPA believes that section 612's reference to ``alternative,'' instead
of ``alternative substance,'' or ``alternative chemical,'' implies a
statutory intent that ``alternative'' be read broadly. This furthers
the statutory desire to shift use to alternatives that reduce overall
risk.
EPA will encourage, where appropriate, alternative processes and
technologies that reduce environmental and human health effects. In
many applications, reliance on alternative processes and/or equipment
may be associated with the use of particular substitute chemicals. In
these instances, EPA encourages the filing of joint submissions where
information is provided by both the chemical manufacturer and, for
example, an equipment manufacturer whose equipment makes use of such a
substitute. Such joint filings will provide the most comprehensive data
on an alternative and its effect on human health and the environment.
f. Second-generation substitutes. A key issue is whether there
exists a point at which an alternative should no longer be considered a
class I or II substitute as defined by section 612. The Agency believes
that as long as class I or II chemicals are being used, any substitute
designed to replace these chemicals is subject to review under section
612. In this final rule, the Agency has determined that second-
generation replacements, if they are non-ozone depleting and are
replacing non-ozone depleting first-generation alternatives, are exempt
from reporting requirements under section 612. Other regulatory
programs (e.g., other sections of the CAA, or section 6 of TSCA) exist
to ensure protection of human health and the environment in these
situations.
Where second-generation substitutes replace first-generation
substitutes that are themselves ozone-depleters (e.g., HCFCs), these
second-generation substitutes are bound by the same notification and
review requirements under section 612 as first-generation substitutes
to ozone-depleting chemicals. For example, if a hydrofluorocarbon (HFC)
is introduced as a first-generation refrigerant substitute for either a
class I (e.g., CFC-12) or class II chemical (e.g., HCFC-22), it is
subject to review and listing under section 612. Future substitutions
to replace the HFC would then be exempt from reporting under section
612 because the first-generation alternative did not deplete
stratospheric ozone. If, however, a class I or class II chemical is
used as a first-generation substitute (e.g., use of HCFC-141b as a
transitional replacement in foam blowing), the second-generation
substitute is still subject to review under section 612 because it is
replacing a class I or class II chemical.
The key to determining whether a substitute is exempt or not as a
second-generation substitute is, as discussed above, what it is
designed to replace. For example, SNAP reviews are not meant to cover
cases in which a technology is designed for use primarily in replacing
existing non-ozone depleting evaporative cooling systems. In general,
if most intended uses for a possible substitute are to replace a non-OD
substitute for a class I or class II substance, then this substance
would therefore be a second-generation substitute, and SNAP review is
unlikely to be required. In those situations where class I or class II
substitutes have already been replaced in most applications, the small
use exemption could also eliminate the need for review of next
generation substitutes.
g. Applicability to existing uses. The prohibition on use of an
alternative applies only to substitutions to unacceptable substitutes
made after the effective date of any final rulemaking for
unacceptability. However, for this final rule, any person who has
transitioned to a substitute for an end-use prior to any SNAP final
rulemaking designating it as unacceptable may continue to use the
substitute until their existing supply of the chemical, as of March 18,
1994, is depleted.
Existing inventory of final products manufactured with or
containing a substitute designated unacceptable as a result of final
EPA rule-making within an end-use covered under SNAP could
theoretically be legally sold after listing. Producers should be aware,
however, that they will be effectively barred from selling a substitute
for use once it has been deemed unacceptable under SNAP, because
potential purchasers will not be able to use it. After the effective
date of this final rule, users will not be able to use any additional
supply of a banned substitute purchased after the publication date of
the unacceptable listing.
h. Substitutes produced outside of the United States. Companies
manufacturing substitutes outside the U.S. who are producing solely for
use by entities outside the U.S. are not subject to the requirements of
these section 612 rules. EPA believes that its authority under section
612 extends only to use of substitutes in areas under the jurisdiction
of the United States government. This principle does not apply to
substitutes introduced as replacements for class I and II chemicals at
offshore U.S. installations (e.g., U.S. military bases located in
foreign countries) that are subject to the legal provisions of section
612.
Substitutes manufactured within the U.S. exclusively for export are
subject to SNAP since the definition of use in the rule includes use in
the manufacturing process, which occurs within the United States.
B. Who Must Report
1. General Provisions
As required by section 612(e), anyone who produces a substitute for
a class I substance must provide the Agency with that person's
unpublished health and safety studies on the substitute, as well as
notify the Agency at least 90 days before introducing the substitute
into interstate commerce for significant new use as an alternative.
Also, as discussed in section IV.A.2.c. of this final rule, pursuant to
sections 114, 301 and 612(c) of the CAA, producers of class II
substitutes must abide by the same reporting requirements. Under the
authority of sections 114, 301(a) and 612(c), EPA has determined that
in certain cases, formulators or end-users of substitutes could be
considered to be producers and would therefore be subject to reporting
requirements. This approach is discussed below, in section IV.B.2. To
analyze substitutes under section 612(c), the Agency finds it necessary
under section 301(a) to require that any person who introduces a
substitute in its final form into interstate commerce be considered to
be a producer of the substitute and required to submit information
describing the substitute under section 114. With respect to
substitutes for both class I and II substances, EPA needs all of the
types of information described below, not just health and safety
studies. Such data are needed to allow EPA to fully analyze the overall
risks to human health and the environment presented by alternative
substitutes, as required by section 612(c).
2. Designated Submitters
Several commenters requested clarification on who has primary
responsibility to notify EPA under SNAP. EPA recognizes that a
potential substitute can be developed for introduction into one of the
SNAP sectors at several points in the manufacture-to-use chain. EPA
considers responsibility for notification under SNAP to reside with the
person who first introduces a substitute not otherwise exempted from
reporting requirements into interstate commerce. Therefore, for
example, if a chemical manufacturer introduces a substitute into
interstate commerce for sale as a fire extinguishing agent to replace
an ODS-based extinguishing method, the manufacturer is a designated
submitter under SNAP. If a system manufacturer or a chemical formulator
buys an agent from a chemical manufacturer and subsequently formulates
or engineers it for introduction into interstate commerce as a
substitute for an ozone-depleting means of fire suppression, then in
this case, the system manufacturer or formulator is the designated
submitter. If an end-user develops a proprietary blend or means of fire
suppression using chemical or physical inputs purchased from
manufacturers or formulators and then enters that product into
interstate commerce as a replacement for ozone-depleting means of fire
suppression, then the end-user is in this case the designated
submitter.
a. Chemical manufacturers. Chemical manufacturers producing a
substitute in its final form are required to notify the Agency of the
existence of that substitute. For instance, if a chemical manufacturer
intends to market a new chemical as a substitute foam blowing agent to
companies that manufacture insulation products, the chemical
manufacturer would be required to notify the Agency about the existence
of the substitute.
b. Formulators. A formulator is engaged in the preparation or
formulation of a substitute, after chemical manufacture of the
substitute or its components, for distribution or use in commerce.
Formulators usually only sell substitutes based on existing chemicals,
since they do not ordinarily possess chemical manufacturing
capabilities. Chemicals used in such substitutes are frequently in
common use and have already been accepted for general use through other
chemical review programs such as under TSCA or FIFRA.
However, to the extent that these formulators can be considered to
be directly responsible for production of the substitute for an end-
use, for example by offering a tailored formulation for an industrial
cleaning process, these formulators would be subject to reporting
requirements as outlined in this final rule. In such cases, the
formulator is best suited in the manufacture-to-use chain to present
information on how substitutes based on existing chemicals are or could
be used. In cases where the manufacturer of a chemical is also the
formulator of a blend, the manufacturer would be responsible for
meeting reporting requirements on the substitute.
The Agency does not foresee a situation where any person who simply
re-packages a substitute, i.e. does not in any way alter the chemical
or physical characteristics of the substitute, would be the designated
submitter. However, if the act of re-packaging a product is intended
solely to allow for the introduction of a substitute into interstate
commerce, that person would be the designated submitter under SNAP.
c. End-users. In general, end-users of substitutes will not be
obligated to meet the reporting requirements discussed in this final
rule, except in rare cases where the end-user and the producer of the
substitute for commercial introduction in final form are the same
person. While the Agency expects that this situation will occur
infrequently, several large companies have developed substitutes for
their own use and subsequently have notified EPA of their intent to
offer those substitutes for commercial sale. Because EPA intends to
require end-users to report only on those substitutes they plan to
introduce into interstate commerce, evaluating and listing such
substitutes will not stifle research and development innovations by
end-users.
3. Exemptions From Reporting
The Agency has identified several situations in which notification
under the provisions of section 612 will not be required. These
exemptions from reporting are discussed below.
a. Substitutes already listed by EPA. As part of this final rule,
the Agency has already completed the review of numerous class I and II
alternatives and has determined that these substitutes are either
acceptable or unacceptable. In preparing these determinations, the
Agency evaluated information either on file or supplied in response to
the NPRM published in the Federal Register on May 12, 1993. The
substitutes list and supporting risk screens are described in more
detail in section IX. No further submission is needed for any of those
substitutes already listed as acceptable or unacceptable in this final
rule. However, further information may be required for those
substitutes listed as pending review in appendix B.
b. Small sectors. Most ozone-depleting substances have been or are
currently used in large industrial sectors such as refrigeration and
air conditioning or foam blowing. However, there are also numerous
small uses of class I or II substances that fall outside of these major
use sectors. While small use applications for class I and II compounds
are varied and numerous, in the aggregate these small uses do not
contribute substantially to ozone depletion. The Agency estimates that
across all sectors these varied but small sector uses comprise in
aggregate at most seven percent of total U.S. consumption of ozone-
depleting substances. For more detail on the Agency's analysis and
rationale for exempting small sectors, readers should refer to the
Notice of Proposed Rulemaking for SNAP (58 FR 28094) published May 12,
1993.
Accordingly, eight major industrial use sectors are covered in this
final rule. They are refrigeration and air conditioning, foam blowing,
fire suppression and explosion protection, solvents cleaning,
adhesives, coatings, and inks, aerosols, sterilization and tobacco
expansion. Analysis of substitutes in a ninth sector, pesticides, will
be completed, and the resulting decisions will be added to future SNAP
determinations published in the Federal Register as part of EPA's
quarterly updates to the lists of acceptable and unacceptable
substitutes. EPA does not plan to add sectors other than the nine
principal sectors listed above to the formal analyses performed under
SNAP, unless the Agency receives additional data indicating that
inclusion of additional sectors is warranted based on the potential for
high risks to human health and the environment due to class I and II
alternatives.
c. Small volume use within SNAP sectors. As noted above, most
ozone-depleting substances have been or are currently used in large
industrial sectors such as refrigeration or fire extinguishing.
However, even within these sectors, the potential for adverse effects
on human health and the environment is related to the aggregate amount
of ozone-depleting material consumed in an end-use. Thus, the Agency is
focusing the SNAP determinations on large-volume uses in the major
industrial sectors. Given the breadth of EPA's required overall risk
assessment, the imposition on small volume uses within any sector of a
requirement for a full SNAP submission seems unjustified by the
potential for risk posed by these small uses.
Moreover, a key policy interest in the SNAP program is promoting
the quickest possible shift from the ODSs into alternatives posing
lower overall risk. The speed and orderliness of this shift depends in
part on clear early determinations from EPA on the acceptability of key
substitutes. Focusing the SNAP program on all possible substitutes in
every conceivable use could diminish EPA's ability to provide an early
and clear message on those substitutes which can contribute most to
solving the problem of general reliance on ozone-depleting chemicals.
Further, the small volume use exemption is an exemption from the
notification requirement only. It does not, for example, authorize the
use in any quantity of a substitute otherwise deemed unacceptable under
SNAP. Since the responsibility for meeting the notification requirement
resides with the person introducing the substitute into interstate
commerce, whether manufacturer, formulator, or end-user, this person is
also responsible for ascertaining whether annual use of the substitute
in its intended sector will exceed 10,000 pounds per year.
Thus, those introducing substitutes for ozone-depleting compounds
in annual quantities of 10,000 pounds per year or less for any given
major industrial sector identified in this rule need not notify EPA of
their activities under SNAP. The exemption applies regardless of
whether the Agency is notified for the same substitute for any
conceivable application in the other major sectors covered under SNAP,
or whether the introducer's total sales are 10,000 pounds or less for
any or all of the other major SNAP sectors.
Those taking advantage of the exemption for small uses must
maintain documentation describing the basis for their view that any
substitute being used meets this small use definition. This
documentation must include annual production and sales information by
sector, and could be necessary in the event the Agency receives a
petition to add such substitutes to its evaluations under SNAP, or to
assure adequate enforcement of the notification requirement.
d. Research and development. Substitutes manufactured or imported
solely for research and development are exempt from reporting
requirements under section 612. Several commenters, including Federal
agencies involved in research on CFC-related substitutes, support this
exemption. Amounts used in research are assumed to be the minimum
necessary for reasonable scientific experimentation. For new chemicals,
the provisions of 720.36 of the PMN rule (40 CFR part 720) are in
effect.
e. Test marketing. Use of alternatives for the sole purpose of test
marketing is exempt from any reporting requirements under section 612.
Persons taking advantage of this exemption, are, however, required to
notify the Agency in writing that they are conducting test marketing
prior to the commencement of sale into interstate commerce.
Notification must be sent 30 days prior to the test marketing period,
and must include the name of the substitute used, the volume used in
the test marketing, and the expected duration of the test marketing.
Once a company decides to sell an alternative as a class I or II
substitute, it must provide the Agency with formal notification at
least 90 days prior to the introduction of the substitute into
interstate commerce for significant new use as a substitute for a class
I or II chemical.
For new substitute chemicals that are being test marketed, the
producer must abide by the provisions of section 5(h)(1) of TSCA, which
authorizes the EPA, upon application, to grant exemptions from TSCA-
reporting requirements, provided that test marketing will not present
an unreasonable risk to human health or the environment.
f. Formulation changes. In general, the Agency believes that
changes in formulation needed to accommodate replacement of class I and
II compounds should not be subject to the provisions of section 612.
Such changes may be necessary, for example, when a new blowing agent in
foam manufacture necessitates the replacement of the catalyst formerly
used with the class I blowing agent. The Agency believes that other
regulatory mechanisms (e.g., TSCA) are available for examining and
controlling, as needed, any adverse environmental and human health
effects associated with subsequent formulation modifications. However,
the manufacturer overseeing the formulation change is required to
notify the Agency if these modifications may significantly influence
the environmental and human health risk characteristics associated with
the class I or II substitute. Also, the Agency reserves the right to
exercise its discretion to examine formulation changes if a problem
appears to exist.
g. Substitutes used as feedstock. Commenters to the NPRM supported
the Agency's proposal to exempt substitutes that could replace class I
chemicals used solely as intermediates in the production of other
chemicals. To the extent that any feedstock substitutions occur, the
Agency believes that they will not contribute substantially to any
incremental risk to human health and the environment. This is because
intermediates are used as inputs in production of other compounds, and
as a result are largely consumed in the chemical manufacturing process.
V. Information Submission
A. Overview
To develop the list of unacceptable and acceptable substitutes for
various end-uses as required by section 612(c), the Agency must assess
and compare the ``overall risks to human health and the environment''
posed by use of substitutes, and this assessment must be performed in
the context of particular applications. To conduct this overall
examination, the Agency must consider a wide range of health and
environmental factors. In order to reduce the burden on the regulated
community, the Agency will defer to data collection requirements under
other regulatory authorities to the maximum extent practicable. In the
section that follows, the Agency presents information required by the
SNAP program to evaluate class I and II substitutes. A copy of the SNAP
Information Notice can be obtained from the SNAP program at the address
listed in the beginning of this final rule.
B. Information Required
1. Name and Description of the Substitute
A chemical substitute should be identified by its chemical name,
trade name(s), identification numbers (e.g. Chemical Abstract Service
(CAS) registry), chemical formula and chemical structure. If a
substitute is a blend, the percentage of each component must also be
provided. Alternative technologies or manufacturing processes should be
described in sufficient detail as to uniquely identify its use as a
class I and II substitute.
2. Physical and Chemical Information
Key properties needed to characterize chemical substitutes include:
molecular weight; physical state; melting point; boiling point;
density; odor threshold; solubility; partition coefficients (Log
Kow, Log Koc); and vapor pressure. For alternative
technologies or manufacturing processes, technical details on health,
environmental or safety issues associated with use should be provided.
3. Substitute Applications
Identification of the end-use in which the substitute is likely to
be used is required. It is essential to provide a complete list of
potential end-uses and of applications within those end-uses because
section 612(c) requires the Agency to list substitutes by specific
uses.
4. Process Description
For each identified end-use application, the Agency requires
descriptive data on processing, including in-place pollution controls.
Such information will be used to characterize workplace and
environmental releases and exposures.
5. Ozone Depletion Potential
The predicted 100-year ozone depletion potential (ODP) of
substitute chemicals relative to CFC-11 is required. The submitter
should also provide sufficient supporting documentation--either a
citation or the background information used to develop the ODP. For
purposes of calculating ODP, the Agency recommends the methodology used
in the most recent Scientific Assessment of Ozone Depletion: 1991,
which was prepared for the United Nations Environment Programme. (1)
6. Global Warming Potential
The Agency requires data on the potential total global warming of
the substitute in its particular end-use (e.g., as a refrigerant, foam
blowing agent, etc.). The total global warming considers both direct
and indirect impacts. Direct impacts refer to the direct contribution
to global warming of using a substitute. Calculation of the global
warming potential (GWP) index for a 100, 500, and 1000 year time
horizon, as well as the atmospheric lifetime and infrared adsorption
spectrum of the substitute used to calculate the GWP is required. The
Agency is requesting that all GWPs be referenced to CO2 using the
methodology recommended by the Intergovernmental Panel for Climate
Change (IPCC).(2) Indirect impacts explicitly consider the effect on
global warming arising from changes in energy consumption associated
with the use of a substitute (e.g., an alternative refrigerant). This
latter measure can be identified as changes in energy efficiency
resulting from use of the substitute relative to that of the substance
being replaced.
7. Toxicity Data
To assess the overall risks to human health and the environment,
information is required on the acute and chronic toxicity of a
substitute chemical, its impurities, and its degradation products on
any organism (e.g., humans and other mammals, fish, wildlife, and
plants). To characterize the risk to humans, the Agency is requesting a
minimum submission of the following mammalian tests: A rangefinding
study that considers the appropriate exposure pathway for the specific
use (e.g. inhalation, oral, etc), and a 90-day subchronic repeated dose
study in an appropriate rodent species (e.g. rats or mice). For some
substitutes, a cardiotoxicity study, usually measuring cardiotoxic
effects in the dog, is also required. Additional mammalian toxicity
tests will be identified by EPA on a case-by-case basis depending on
the particular substitute and application being evaluated. To
characterize aquatic toxicity, both acute and chronic toxicity data for
a variety of species are required. The Agency requires a minimum
aquatic data set to be submitted as described in ``Guidelines for
Deriving Numerical National Water Quality Criteria for the Protection
of Aquatic Organisms and Their Uses,'' which is available through the
National Technical Information Service (#PB 85-227049). All toxicity
data in the submitter's possession and any other available hazard
information, including Material Safety Data Sheets (MSDS), must also be
submitted. Submission of the actual toxicity studies is recommended;
however, it is not necessary to submit these reports if they have been
supplied to the Agency as part of other regulatory submissions. If
studies are not submitted, however, the submitter must provide
sufficiently clear references that the Agency can locate the studies
without delay. As discussed below in section V.C.3., data concerning
the objectives, methodology, results or significance of any toxicity,
metabolism, translocation, or persistence test for a substitute and its
degradation products cannot be held as CBI where such data are also
submitted under TSCA and FIFRA to the extent that confidential
treatment is prohibited under those statutes. Submitters providing
information on new chemicals for joint review under the TSCA and SNAP
programs may be required to supply additional toxicity data under TSCA
section 5.
8. Environmental Fate and Transport
Where available, EPA requests information on the environmental fate
and transport of substitutes. Such data shall include information on
bioaccumulation, biodegradation, adsorption, volatility,
transformation, and other data necessary to characterize a substitute's
movement and reaction in the environment.
9. Flammability
Data on the flammability of a substitute chemical or mixture is
required. Specifically, the flash point and flammability limits are
needed, as well as information on the procedures used for determining
the flammability limits. Testing of blends should identify the
compositions at which the blend itself is flammable, and the changes in
the composition of the blend during various leak scenarios. For
substitutes that will be used in consumer applications, documentation
of testing results conducted by independent laboratories (e.g.,
Underwriters Laboratories) should be submitted, where available. If a
substitute is flammable, the submitter must analyze the risk of fire
resulting from the use of such a substitute and suggest measures to
minimize these risks.
10. Exposure Data
The submitter must provide available modeling or monitoring data on
exposures associated with the manufacture, formulation, transport, and
use of a substitute. Descriptive process information for each
substitute application, as required above, will be used to develop
exposure estimates where exposure data are not readily available.
Depending on the end-use, exposure profiles will be needed for workers,
consumers, and the general population.
11. Environmental Release Data
Data on emissions from the substitute application and equipment, as
well as pollutant releases or discharge to all environmental media
(ambient air, surface and groundwater, hazardous/solid waste) are
needed to complete the risk characterization. Submitters should provide
information on release locations, if known. Available information on
pollution controls that are used or could be used in association with
the substitute (e.g., emissions reduction technologies, wastewater
treatment, treatment of hazardous waste) and the costs of such
technology is also requested.
12. Replacement Ratio for a Chemical Substitute
The Agency requires information on the replacement ratio for a
chemical substitute versus the class I or II substances being replaced.
The term ``replacement ratio'' refers to how much more or less of the
substitute chemical is needed to substitute for the original ozone-
depleting compound being replaced. This ratio will affect the estimated
incremental cost and environmental effects associated with use of the
substitute.
13. Required Changes in Technology
Data on any changes in technology needed to use the alternative are
required. Such information should include a description of whether the
substitute can be used in existing equipment--with or without some
retrofit--or only in new equipment.
14. Cost of Substitute
The Agency requires data on the expected average cost of the
alternative. The cost of the substitute can be expressed, for example,
in terms of $/pound (for a chemical substitute) or as incremental
capital and operating costs associated with a retrofit or new
equipment. In addition, information is needed on the expected equipment
life for an alternative technology. Other critical cost considerations
should be identified, as appropriate. For example, it is important to
understand the incremental costs associated with losses or gains in
energy efficiency associated with use of a substitute relative to
current experience with existing substances.
15. Availability of Substitute
The Agency needs to understand the extent to which a substitute is
already commercially available or the date on which it is expected to
become available. The timing of availability is an important factor in
assessing the overall health and environmental effects of the
substitute.
16. Anticipated Market Share
Data on the anticipated near-term and long-term (over the next ten
years) nationwide substitute sales are also required. This information
can be presented in several ways, for example: a percentage of existing
nationwide use of class I or II chemicals that would be replaced in a
particular end-use; number of units/products to be produced; or pounds
of substitute to be sold. This information is required to assess the
potential effects of a substitute related to total consumption and
environmental releases.
17. Applicable Regulations Under Other Environmental Statutes
The submitter is required to provide information on whether the
substitute is regulated under other statutory authorities, in
particular the Clean Water Act; the Safe Drinking Water Act; the
Resource Conservation and Recovery Act; the Federal Insecticide,
Fungicide, and Rodenticide Act; the Toxic Substances Control Act; the
Comprehensive Environmental Response, Compensation and Liability Act;
the Emergency Planning and Community Right-to-Know Act, and other
titles of the CAA. The Agency will evaluate substitutes under the SNAP
program subject to existing regulatory constraints.
18. Information Already Submitted to the Agency
Individuals may have already submitted information required in the
SNAP Information Notice to the Agency as part of past regulatory and
information-gathering activities. In this case, to minimize reporting
burden, the submitter need not resubmit the data but instead should
provide the following information to help EPA locate the data already
maintained at EPA: Type of information submitted; the date of
submission; the EPA office to which the data were sent; description of
the regulatory program under which the data were submitted; and a
document-control number, if assigned (e.g., a PMN number). If the
submitter cannot provide adequate references for data sent previously
to the Agency as described above, all required information should be
included in the SNAP notice. To facilitate review under SNAP, reports
already submitted to the Agency as part of other regulatory submissions
should be resubmitted if the original information was claimed as
Confidential Business Information when previously submitted.
19. Information Already Available in the Literature
If any of the data needed to complete the SNAP program notice are
available in the literature, the submitter should provide the Agency
with references for such information. Failure to provide the Agency
with an accurate and complete citation may delay review of the notice.
Additionally, submitters are encouraged to provide copies of any
literature to expedite review, particularly if the citation is from a
source not readily available. Any references from sources in foreign
languages should be translated into English prior to submission.
Submissions should be sent to the SNAP Coordinator at the address
referenced at the beginning of this final rule. All submissions must be
provided in three complete copies. If information is claimed as
confidential, all confidential information must be excised from one of
the three copies. This copy will be placed in the public docket. The
other two copies should include the confidential material. If no claims
of confidentiality are made for the submission, all three copies should
be identical. (See below, as well as appendix C, for further guidance
on handling of confidential information under SNAP.)
C. Submission of Confidential Business Information
1. Clean Air Act Provisions
Anyone submitting information for which Confidential Business
Information (CBI) status is requested must assert a claim of
confidentiality at the time of submission. Failure to assert a claim of
confidentiality at the time of submission may result in disclosure of
the information by the Agency without further notice to the submitter.
Further, it should be noted that information which is publicly
available (e.g., in journals, trade magazines, product literature,
etc.) cannot be claimed as CBI. Requesting CBI status for such
information could delay review under section 612. All claims of
confidentiality will be treated in a manner consistent with 40 CFR part
2, subpart B.
The submitter should be advised that under CAA section 114(c),
emissions data may not be claimed as confidential. Moreover, there are
further instances in which confidentiality assertions may later be
reconsidered by the Agency even when confidentiality claims are
originally received. These circumstances are provided in the provisions
of 40 CFR part 2, subpart B. The submitter will be contacted as part of
this evaluation process when such a circumstance occurs.
2. Substantiation of Confidentiality Claims
In the NPRM, EPA proposed to require substantiation of any
confidentiality claims at the time of submission. In making these
claims, the following provisions apply:
--The specific information to which the claim applies must be clearly
marked in the body of the study as subject to a claim of
confidentiality;
--A Supplemental Statement of Data Confidentiality Claims must be
submitted, identifying each section claimed confidential and describing
in detail the basis for the claim. (A list of points to address in such
a statement is included in appendix C);
--The Supplemental Statement of Data Confidentiality Claims must be
signed and dated and must include the typed name and title of the
official who signed it.
EPA also stated that if required substantiation is not provided
when submitting information claimed as confidential, the complete
submitted information may be made available to the public without
further notice to the submitter.
Several commenters indicated that EPA should contact the submitter
before releasing information marked as confidential to the public even
if it does not contain adequate substantiation. One commenter also
indicated that complete substantiation should not be required until the
end of the 90 day review period and that any issue regarding the
adequacy of CBI substantiation should not delay the review process.
EPA agrees with the comment that submitters should be notified
prior to disclosure to the public of information marked as confidential
where substantiation, although it may be inadequate, has been provided.
This will give the submitter opportunity to provide the necessary
additional substantiation or withdraw the submission. However, an
acceptability determination on a substitute will not be published until
all claims of CBI have been fully substantiated under the provisions
described above. Additionally, should no substantiation of CBI claims
be provided, EPA may make the complete submittal available to the
public without further notice to the submitter.
3. Confidentiality Provisions for Toxicity Data
In the event that toxicity or health and safety studies are listed
as confidential, the submitter should be advised that this information
cannot be maintained as confidential where such data are also submitted
under TSCA or FIFRA to the extent that confidential treatment is
prohibited under those statutes. However, any information other than
emissions data contained in the toxicity study that is not health and
safety data and is not relevant to the effects of a substance on human
health and the environment (e.g., discussion of process information,
proprietary blends) can be maintained as confidential subject to the
provisions of 40 CFR part 2, subpart B. The Agency is therefore
requesting that submitters not identify the following information as
confidential when submitting information under TSCA or FIFRA: All
information concerning the objectives, methodology, results, or
significance of any toxicity test or experiment performed on or with a
substitute or its degradation products; any information concerning the
effects of the substitute on any organism (e.g., fish, wildlife, humans
and other mammals) or the environment (e.g., studies related to
persistence, translocation, and fate); and pharmacokinetics/metabolism
studies.
4. Federal Register Requirements
As discussed below in Section VII.A.3.g., the Agency will publish
quarterly notices in the Federal Register updating the list of
acceptable and unacceptable alternatives. If the name of a specific
substitute contained in any studies supporting such notices must be
maintained as confidential, the submitter and the Agency will together
develop a generic name that will protect the proprietary nature of the
substitute, but will provide sufficient detail for the public to
evaluate the health and safety studies. If appropriate, the submitter
may reference any generic names identified for use in the PMN program.
D. Display of OMB Control Numbers
EPA is also amending the table of currently approved information
collection request (ICR) control numbers issued by OMB for various
regulations. This amendment updates the table to accurately display
those information requirements contained in this final rule. This
display of the OMB control number and its subsequent codification in
the Code of Federal Regulations satisfies the requirements of the
Paperwork Reduction Act (44 U.S.C. 3501 et seq.) and OMB's implementing
regulations at 5 CFR part 1320.
The ICR was subject to public notice and comment prior to OMB
approval. As a result, EPA finds that there is ``good cause'' under
section 553(b)(B) of the Administrative Procedures Act (5 U.S.C.
553(b)(B)) to amend this table without prior notice and comment. Due to
the technical nature of the table, further notice and comment would be
unnecessary. For the same reasons, EPA also finds that there is good
cause under 5 U.S.C. 553(d)(3).
VI. Effective Date of Coverage
A. General Provisions
This final rule includes a list of acceptable substitutes and a
list of unacceptable substitutes. Unacceptable substitutes cannot be
used in manufacturing or in final applications as substitutes for
ozone-depleting compounds. The list of unacceptable substitutes and
acceptable substitutes subject to use restrictions becomes binding 30
days after March 18, 1994. In contrast, the list of fully acceptable
substitutes is furnished for the purpose of assisting users in
understanding the full range of available, acceptable substitutes in
each application. Many of the substitutes listed as pending or proposed
in the NPRM have since been added to the final acceptable or
unacceptable lists.
As noted above, the Agency does not believe that determinations on
substitutes that are acceptable with no use restrictions need be made
through rulemaking. Consequently, EPA believes that it is within its
discretion to supplement the list of acceptable substitutes at any time
upon making determinations consistent with the criteria established in
this rulemaking. Until the Agency reaches a final decision restricting
the use of a substitute, vendors are not barred from selling such
substitutes once notification is given and the 90 day prior-to-sale
notification period expires.
B. Grandfathering of Unacceptable Substitutes
EPA is authorized to permit the continuation of activities
otherwise restricted where the balance of equities supports such
grandfathering. Consequently, where appropriate, EPA may grandfather
the production and use of particular substitutes by setting the
effective date of unacceptability listings in the future.
The United States District Court for the District of Columbia
Circuit has established a four-part test to judge the appropriateness
of Agency grandfathering (see Sierra Club v. EPA, 719 F.2d 436 (DC Cir.
1983)). This test involves balancing the results of four analyses,
including whether the new rule represents an abrupt departure from
previously established practice, the extent to which a party relied on
the previous rule, the degree of burden which application of the new
rule would impose on the party, and the statutory interest in applying
the new rule immediately. In each rulemaking listing a substitute as
unacceptable where grandfathering seems appropriate, EPA will conduct
these four analyses and weigh their results. Where the balance of
equities favors grandfathering, EPA will set a delayed effective date
for such listings.
Setting future effective dates to ban the sale and distribution of
specific substitutes will allow the Agency to avoid penalizing those
who in specific applications may have already invested in good faith in
alternatives the SNAP program determines to be unacceptable. For
example, the Agency in this final rule finds unacceptable the use of
HCFC-141b in solvent applications. New information on stratospheric
ozone depletion has increased concern over possible adverse human
health and environmental effects, and the Agency's unacceptable
determination in the case of HCFC-141b reflects these concerns.
However, the Agency recognizes that some solvent users may have
switched to HCFC-141b in good faith, expecting that this substitute
would sufficiently lower the risk of ozone depletion relative to
earlier materials. To provide for these users, the Agency has extended
the effective date for certain end users of HCFC-141b. See the listing
determination narrative discussion in section IX.F., as well as the
listing tables in appendix B, for a full discussion of HCFC-141b and
associated effective dates. Finally, to balance the desire not to
penalize those who switched early in good faith with the need to avoid
creating an incentive for continued investment in alternatives the
Agency wishes to discourage, the longer-term effective dates discussed
above will affect only existing uses.
VII. Notice, Review, and Decision-making Procedures
The purpose of this section is to summarize the procedures for
submitting the required information to the Agency, the steps EPA will
take in reviewing SNAP submissions, and the process of making
determinations based on these reviews. This section focuses on three
procedures, summarized in Exhibit 1, depending on the nature of the
submission received by the Agency. Some substitutes may already be
approved or may not need approval under other environmental statutes,
especially TSCA and FIFRA. These substitutes, in consequence, would
only require review under the SNAP program. Section VII.A. discusses in
greater detail the submission and review process for alternatives that
fall into this category. In other cases, a substitute will require
review under section 612 as well as relevant provisions of TSCA and
FIFRA. With respect to any substitute that is a new chemical (i.e., not
currently listed on the TSCA inventory), information must be submitted
to the Agency for review both under the SNAP program and the PMN
program. Section VII.B. describes steps for this review in more detail.
For alternatives to class I and II chemicals that will be used in
pesticide products, the substitute manufacturer will need to file
notification jointly with EPA's Office of Pesticide Programs (OPP) and
EPA's SNAP program. Section VII.C. discusses the latter procedure. The
SNAP program has coordinated closely with each of these regulatory
programs to establish a joint review process that will ensure
consistency in the final decisions, while minimizing the time for
review, the reporting burden, and the costs for both the submitter and
the Agency.
Billing Code 6560-50-P
TR18MR94.000
TR18MR94.001
BILLING CODE 6560-50-C
A. Substitutes Reviewed under SNAP Only
1. Applicability
Sections IV. and V. describe the conditions dictating review under
the SNAP program only and the general reporting requirements under
section 612. If any of these conditions are met and the substitutes are
not exempt as described in section IV.B.3., Exemptions from Reporting,
a SNAP notice must be submitted.
2. Pre-Notice Communication
Prior to submitting the SNAP notice, each submitter is encouraged
to contact EPA's SNAP Coordinator to discuss the notification process.
Among other things, the SNAP Coordinator will: (1) Assist the potential
submitter in determining whether a SNAP notice is needed; (2) answer
questions regarding how to complete a submission; (3) provide all
necessary forms and the guidance manual; (4) serve as the initial point
of contact when the notice is submitted; and (5) oversee the assignment
of a SNAP program tracking number to the notice once it is received by
the Agency. A copy of the SNAP Information Notice and Guidance Manual
may be obtained from the SNAP Coordinator at the address listed at the
beginning of this final rule. Specific data requested are described in
section V.
3. Processing of Completed SNAP Submission
a. 90-Day review process. As required under section 612(e), a
manufacturer of a substitute for a class I chemical must provide the
Agency with notification at least 90 days prior to introducing into
interstate commerce any new or existing chemicals for significant new
uses as class I alternatives. The same requirements apply to
manufacturers of substitutes for class II substances, although in this
case the Agency is drawing on general authorities contained in sections
114 and 301 of the CAA in order to fulfill the purpose of section
612(c). EPA intends to review these substitutes within a 90-day period
to ensure prompt response for manufacturers initiating production of
substitutes. EPA's 90-day review period for SNAP submissions begins
once EPA receives a submission, as described in section V.B. above. If
a submission does not include adequate data, EPA may return the
submission to request specific additional information. Section 114 and,
in the case of petitions, section 612(d) authorizes EPA to require
manufacturers to support their SNAP submissions with data adequate to
facilitate EPA's review.
b. Initial receipt of the SNAP submission. (1) Initial review of
submission. EPA will conclude a completeness review of each submission
within fifteen days of receipt of the submission. Within the 15-day
period, EPA will inform the submitter of any additional information
needed. If EPA makes no such request, then after the 15-day period is
concluded, the 90-day review period will automatically commence. If EPA
does request any additional data, the 90-day period shall not commence
until the additional data are received and themselves reviewed for
completeness.
During the 15-day completeness review, the SNAP Coordinator will
first review the SNAP Information Notice to ensure that basic
information necessary to process the submission is present (i.e., name
of company, identification of substitute, etc.). A more detailed review
of supporting technical data will then ensue, as well as an examination
of substantiation provided for any claim for confidentiality of
information. Should additional information be required, EPA will
contact the submitter within 15 days of receipt of the original
submission.
During the 90-day review period, EPA may ask for additional
information from submitters as necessary, although manufacturers of a
new substitute may introduce the substitute into interstate commerce 90
days after EPA receives a submission for the product if the Agency has
not already rendered an unacceptability determination. In the case of a
substitute which already exists in the marketplace prior to the
issuance of this final rule, manufacturers must submit a completed SNAP
Information Notice as soon as possible, and not later than 90 days
after the effective date of this rule. During EPA's review, use of an
existing substitute may continue, and need not cease unless and until
EPA adds the substitute to the list of unacceptable substitutes as a
result of notice-and-comment rulemaking.
(2) Letter of receipt. The SNAP Coordinator will send a letter of
confirmation to the submitter once the Agency has received the SNAP
Information Notice and reviewed it for completeness. This letter will
include the date of advance notification to the Agency, the starting
date of EPA's 90-day review period, and the SNAP program tracking
number assigned to the submission.
c. Determination of data adequacy. As part of the review for a SNAP
submission, the Agency will complete a preliminary determination of the
adequacy of data supporting the application. The Agency will issue this
determination within 15 days after receipt of the application. At any
time during the review period, if information is not adequate to allow
the Agency to reach a SNAP determination, EPA will contact the
submitter and request the missing data. EPA believes it appropriate and
authorized under section 114 to require the submitter to provide all
data needed to complete the review of the SNAP notice. Depending on the
type of information needed and the time necessary to compile and submit
the requested data to the Agency, EPA may suspend or extend the review
period. This will not affect the ability of a manufacturer to begin
marketing a new substitute 90 days after advance notification to the
Agency, or in the case of a pre-existing substitute, to continue
marketing.
In a few cases, the Agency and the submitter may disagree on a
schedule for furnishing additional data EPA deems necessary to
determine the acceptability of the substitute. If in these cases EPA
has reason to believe that such a substitute may be unacceptable, the
Agency may exercise the option of proposing to list the substitute as
unacceptable based on existing data until the necessary data are
provided, due to the uncertainty of the risks associated with use of
the substitute.
d. Availability of new information during review period. If
critical new information becomes available during the review period
that may influence the Agency's evaluation of a substitute, the
submitter must notify the Agency about the existence of such
information within ten days of receiving such data. The submitter must
also inform the Agency of new studies under way, even if the results
will not be available within the 90-day review period. The Agency may
extend or suspend the review period depending on the type of
information at issue and the stage of review. Again, this will not
affect a manufacturer's ability to market a substitute 90 days after
initial notification to the Agency.
e. Completion of detailed review. Once the submission is found to
be supported by adequate data, the Agency will commence a detailed
evaluation of the notice. As this review proceeds, EPA may contact the
submitter for additional scientific and technical information to assist
in the evaluation. This will ensure that the review is completed
quickly and that it reflects the best available information. Final
decisions will be based on detailed analysis completed during this
stage of review.
f. Vendor lists. As part of EPA's outreach and clearinghouse under
SNAP, the Agency will use the SNAP determinations to compile a list of
vendors for the convenience of potential users. Companies could then
ask EPA to review their specific substitute, to ensure that it is
covered by the listing decisions on acceptable substitutes, and to add
the company to the vendor list. The Agency believes that specific
information on vendors of acceptable substitutes would be useful to
companies switching out of class I and II compounds.
g. Communication of SNAP determination. (1) SNAP determinations on
90-Day notifications. EPA's determinations on SNAP submissions that
come as a result of the 90-day advance notification requirement will
take the form of either adding substances to the list of acceptable
substitutes or by proposing to add them to one of the following lists:
acceptable subject to use conditions, acceptable subject to narrowed
use limits, or unacceptable substitutes.
(2) Communication of SNAP determination to the submitter. Once
Agency review has been completed, the submitter will be notified in
writing of the determination under SNAP. At this time, the submitter
will also be informed if any restrictions are attached to the
acceptability of a substitute. Following the expiration of 90 days
after submitting advance notification to EPA, companies may begin sale
or manufacture of a new substitute. They may continue to sell or
manufacture an existing substitute through the review period, unless
and until the Agency places such substitute on the list of unacceptable
substitutes as a result of rulemaking. Sale or manufacture may begin
and continue even if the Agency fails to reach a decision or notify the
submitter of that decision within 90 days of advance notification of
EPA.
(3) Communication of SNAP determination to the public. (a) Federal
Register notice. To provide the public with updated information on SNAP
determinations, the Agency will publish in the Federal Register a
complete list of the acceptable and unacceptable alternatives reviewed
to date. This list will be published four times each year and will
include recent decisions made under the SNAP program. In addition to
the quarterly publications, the Agency will communicate decisions
through a clearinghouse and outreach program, as discussed in the next
section, as well as through the Stratospheric Ozone Protection hotline.
(b) Outreach and clearinghouse. Section 612(b)(4) requires the
Agency to maintain a public clearinghouse of alternative chemicals,
product substitutes, and alternative manufacturing processes that are
available as replacements for class I and II chemicals. The
clearinghouse will distribute information on substitutes that are
acceptable under the SNAP program. For the convenience of companies
wishing to identify substitutes, the Agency will maintain a list of
vendors selling substitutes as discussed in section VII.A.3.f.
In addition, the Agency will enter data on substitutes into the
Pollution Prevention Information Exchange System (PPIES) database,
which is maintained by EPA's Office of Research and Development. This
database contains information on numerous pollution prevention options
for a wide variety of industrial sectors and chemicals. PPIES can also
be accessed from a variety of other pollution prevention databases
maintained by other federal agencies and industry.
4. Decision-Making Framework
a. Decisions by substitute and use. As required by section 612(c),
the Agency must publish a list of substitutes unacceptable under the
SNAP program and a list of acceptable alternatives for specific uses.
Given that environmental exposure and risk profiles can change
significantly from one end-use to the next, it is essential to evaluate
and list substitutes in the context of their intended use. The Agency
identified a number of end-uses in each sector by which to list
substitutes, and section IX provides risk management decisions for many
existing substitutes in each of the principal sectors.
The Agency will be as specific as possible in listing substitutes
by providing exact chemical names of substitutes. For most substitutes,
a broad chemical classification (e.g., aromatic hydrocarbons, or HCFCs)
is not specific enough because of differences among chemicals belonging
to each of these groups. Thus, where appropriate, EPA will provide a
more specific description of the substitute by application.
The Agency anticipates two possible exceptions to this practice.
The first is where release of the chemical identity of a substitute
constitutes release of proprietary information. In that event, the
Agency will report generic chemical names based on chemical classes as
described in section V.C. The other exception would be in cases where
the Agency believes that a more general categorization is needed to
account for the diversity of possible chemicals used in a particular
set of substitutes. For example, in the solvents cleaning sector, many
substitutes are formulations composed of compounds drawn from several
categories of chemicals. In this case, the toxicity profile of each
chemical is similar to those of other chemicals in that class.
b. Decision categories. Under section 612, the Agency has
considerable discretion in the risk management decisions it can make in
SNAP. In this final rule, the Agency has identified five possible
decision categories, as described below. Commenters suggested that
there was confusion with the Agency's intent to designate some
substitutes as acceptable subject to narrowed use limits versus
unacceptable except for critical use exemptions. In response to these
comments, the Agency has determined that the goal of both categories
was to limit the use of a substitute that had generally unacceptable
characteristics yet provide relief for specialized applications within
an end-use where no other alternatives exist. Given the similarity in
goals, the decision categories have been streamlined by eliminating the
category listed in the NPRM as ``unacceptable except for critical use
exemptions.'' Those substitutes that were listed in the NPRM as
proposed unacceptable except for critical use exemptions are listed as
unacceptable in this final rule, and the concerns which the critical
use exemption petition process was created to address will now be
addressed as part of EPA's responsibilities under the section 612(d)
petition process.
(1) Acceptable. Where the Agency has reviewed a substitute and
found no reason to prohibit its use, it will list the alternative as
acceptable in the end-uses for which the submitter provided
information. Where appropriate, the Agency may provide some additional
comment (e.g., general recommendations encouraging recapture and
recycling). However, these comments are not conditions for use of the
substitute.
(2) Acceptable subject to use conditions. As proposed in the NPRM,
after reviewing a submission, the Agency may determine that a
substitute is acceptable if certain conditions on use are adopted. The
Agency cannot predict at this time all necessary restrictions, but has
imposed some conditions based on substitute reviews already completed
for this final rule. Several commenters supported the application of
use conditions as necessary in providing important guidance to
companies in reviewing alternative replacements for ODSs. While also
supporting use conditions generally, other commenters noted that they
should be used sparingly, so as to create the minimum uncertainty in
the regulated community and encourage swift transition.
The Agency agrees with these comments. In this final rule, any
conditions imposed will depend on the risks involved and the substitute
and application in question. For example, the Agency may impose
conditions on the use of a substitute and require recycling equipment
to limit workplace and ambient releases or require use of other control
practices within a certain application. Where a substitute is found
acceptable subject to conditions on uses, use without adherence to the
conditions in the relevant end-use is prohibited in this final rule.
Determinations of acceptability subject to use conditions will only be
made pursuant to notice-and-comment rulemaking.
In implementing conditions on use, the Agency has sought to avoid
overlap with existing regulatory authorities. EPA has taken a number of
steps to mitigate this potential for duplication. First, EPA intends to
restrict the use of conditions to cases in which clear regulatory gaps
exist. Second, these existing regulatory gaps must render the use of a
substitute an unreasonable risk in the absence of any additional
controls. Third, in the limited cases in which conditions may be
necessary, the Agency will impose them only as a result of formal
notice-and-comment rulemaking. Finally, use conditions will be
effective only until other appropriate regulatory controls are imposed
under other authorities and will be withdrawn by the Agency when they
are superseded by such controls.
(3) Acceptable subject to narrowed use limits. The Agency cannot
restrict use of a substitute under SNAP if there are no technically
feasible alternatives to the use of an ozone-depleting compound. Thus,
EPA may approve a compound not for general use within a sector, but for
use only within certain specialized applications within a sector end-
use. EPA refers to these restrictions as narrowed use limits. For
example, the Agency could list a substitute with a generally
unfavorable environmental or human health effect as acceptable in
certain specific metals cleaning applications in the solvents cleaning
sector. This would allow transition away from the damaging ozone-
depleting compounds to proceed, by allowing industry the flexibility to
use in narrow niche applications a substitute which provides the only
means of transition. At the same time, the narrowed use determination
prevents a widespread shift of an entire sector to substitutes which
overall do not offer the risk reduction available through the use of
other alternatives.
Clearly, any limits imposed will depend on the risks involved and
the substitute and application in question. To provide adequate
opportunity for comment by the regulated community, EPA will complete
notice-and-comment rulemaking before promulgating any finding that a
substitute is acceptable only subject to a narrowed use limit.
In implementing narrowed use limitations, the Agency has sought to
allow agents for specific uses that would otherwise be deemed
unacceptable. This policy serves the larger goal of facilitating the
fastest possible transition from ozone-depleting compounds by expanding
the list of alternatives available to all applications within a sector
end-use category. EPA recognizes that certain sector end-uses encompass
a broad range of applications, manufacturing processes and products.
Under the acceptable for narrow use category, EPA will accept a
substitute for use only in certain specialized uses within the broader
end-use. The intent of the narrowed use limitation is to restrict the
use of a substitute that the Agency deems unacceptable for the full
range of applications or products within a sector end-use category.
Where a substitute is found acceptable subject to narrowed use limits,
general use within the relevant end-use is prohibited.
Before users adopt a restricted agent within the narrowed use
limits category, they must make a reasonable effort to ascertain that
other substitutes or alternatives are not technically feasible. Users
are expected to undertake a thorough technical investigation of
alternatives before implementing the otherwise restricted substitute.
The Agency expects users to contact vendors of alternatives to explore
with experts whether or not other acceptable substitutes are
technically feasible for the process, product or system in question. To
further assist users in their evaluation, EPA has prepared a list of
vendors manufacturing other substitutes. Although users are not
required to report the results of their investigation to EPA, companies
must document these results, and retain them in company files for the
purpose of demonstrating compliance. Both the Vendor List and the
Guidance Manual are available from the SNAP program, or through EPA's
Stratospheric Ozone Protection Hotline.
In October 1993, the President directed EPA through the Climate
Change Action Plan (CCAP) to use its authority under section 612 of the
Clean Air Act to narrow the uses of CFC substitutes with high global
warming potential. Because EPA is simultaneously also interested in
promoting the broader shift away from ozone-depleting compounds, EPA
will make every effort to assure that these limits on use will be
imposed in ways that preserve as much flexibility as possible for those
trying to move to alternatives.
In this final rule, EPA has imposed narrowed use limitations on the
acceptability of perfluorocarbon (PFC) substitutes when used in solvent
cleaning, and fire suppression. EPA has imposed these limitations
because of the high global warming potential and long atmospheric
lifetimes of the PFC compounds as compared with other alternatives
available for the same end-uses. Comparable limitations on the use of
refrigerants and aerosols containing PFCs are also likely to be
proposed shortly. In the case of fire suppression and explosion
protection, EPA has taken the approach of narrowing uses to prevent or
delay emissions of global warming gases. This is preferable to the
outright prohibitions EPA would otherwise be authorized to impose where
other alternatives are available, because in these limited cases users
may have no other feasible alternatives to continued reliance on ozone-
depleters.
Through the notice and comment rulemaking process, other companies
or vendors will be able to scrutinize the proposed narrowed use limits.
This may bring to light new alternatives or processes of which the user
and EPA are unaware, and these new alternatives may pose lower overall
risks than the substances which have been the subject of the narrowed
use designation. If an acceptable listing is revoked based on the
availability of a new, lower-risk alternative, companies that have made
investments in technology which was earlier deemed as having no
alternatives available may be granted permission to extend their use
for a limited period of time, consistent with EPA's grandfathering
approach described above in section VI.B.
The Agency has prepared guidance describing additional
documentation users should include for narrowed use applications. This
information includes descriptions of:
Process or product in which the substitute is needed;
Substitutes examined and rejected;
Reason for rejection of other alternatives, e.g.,
performance, technical or safety standards; and/or
Anticipated date other substitutes will be available and
projected time for switching.
In addition to this basic information, the guidance includes
specific data for end-uses in each sector. The guidance is available
from the SNAP program.
(4) Unacceptable. The Agency has the authority under section 612(c)
to prohibit the use of a substitute believed to present adverse effects
to human health and the environment where alternatives that reduce
overall risk are available. The Agency will only use this provision
where it has identified other substitutes that are currently or
potentially available and that pose lower overall risks. Substitutes
will be listed as unacceptable through the rulemaking process.
(5) Pending. The Agency will describe submissions for which the 90-
day review period is underway and for which EPA has not yet reached a
final decision as pending. For all substitutes in the pending category,
the Agency will contact the submitter to determine a schedule for
providing the missing information if the Agency needs to extend the 90-
day review period. EPA will use the authority under section 114 to
gather this information, if necessary. Again, a delay of the review
period will not affect a manufacturer's ability to sell a product 90
days after notification of the Agency as described above.
c. Implications of other regulatory requirements. In evaluating
substitutes, the SNAP program takes into consideration the regulatory
requirements of other environmental and health protection statutes
(e.g., the Clean Water Act or the Occupational Safety and Health Act).
In considering the framework of existing regulatory constraints, the
Agency's evaluation of alternatives will assume compliance with their
provisions.
However, it will not be possible to factor in regulatory
requirements that are still under development (e.g., more stringent
requirements to control volatile organic compounds and hazardous air
pollutants under title I and title III of the CAA). In these instances,
a substitute may be deemed acceptable under SNAP, but is not thereby
excused from compliance with any future regulations. The Agency does
not believe that it was the intent of Congress to use the authority
under section 612 to compromise other regulatory requirements. Should
future regulations severely limit the availability of the only
acceptable substitute for a specific end-use, EPA would reconsider the
advisability of keeping any other alternatives which could be used in
that application on the list of unacceptable substitutes.
5. EPA-Generated Review of Substitutes
In addition to SNAP notifications received under section 612 for
substitute review, the Agency is authorized by section 612(c) to add or
delete alternatives to the list of reviewed substitutes on its own
initiative. EPA has many efforts under way to identify and communicate
the availability of promising new alternatives. These include support
for research efforts to study and focus attention on future
substitutes, involvement in the United Nations Environment Programme's
biannual assessment of technologies for key sectors currently using
ozone-depleting chemicals, and technology transfer projects with
industry, other federal agencies, and developing nations. Based on
information available through these activities, EPA may initiate review
of new substitutes under section 612. In each case, the next planned
quarterly Federal Register notice updating the status of SNAP
determinations will inform the public that EPA is initiating a review,
subject to the provisions discussed in this final rule. Similarly,
determinations ultimately reached as a result of these internally-
generated reviews will be included in these quarterly updates.
B. Joint Review of New Substitutes under SNAP and TSCA PMN
1. Applicability
Any potential SNAP submitter who intends to introduce a new
chemical (i.e., a chemical not currently included in the TSCA
inventory) as an alternative for a class I or class II chemical must
undergo review not only under section 612, but under section 5 of TSCA
(the Premanufacture Notice program) as well. Because of the overlap in
statutory authority, the Agency has established a joint review process
between the SNAP and TSCA Premanufacture Notice (PMN) programs. This
process has been structured to minimize reporting burden and to ensure
consistency in decisions between the two programs. The following
sections describe the joint review and decision-making process in more
detail.
2. Data Submission Requirements and Process
a. SNAP and PMN forms. The Agency has reviewed the data submission
needs for the SNAP and PMN programs and found significant overlap. In
general, the Agency has identified only a few additional data elements
beyond those already required by the PMN program that should be
included for review under the SNAP program. These elements are:
Ozone depletion potential.
Global warming potential.
Cost of using the substitute, including:
--Chemical replacement data.
--Chemical cost data.
--Incremental equipment expenditures (either new or retrofit) needed to
use substitute.
--Information on the cost implications of changes in energy consumption
(e.g., from the use of a less or more energy-efficient refrigerant).
Documentation of testing results regarding the
flammability of substitutes, especially when proposed for consumer
applications.
Given this overlap, a submitter requesting a review under both the
SNAP and PMN programs should provide the above information by following
these steps:
Complete the PMN form (EPA Form 7710-25) following the
Instructions Manual currently available through the TSCA Assistance
Information Service.
Indicate on page 11 of the PMN form, ``Optional Pollution
Prevention Information,'' that the chemical to be reviewed is also to
be considered under the SNAP program.
Complete a SNAP addendum that requests information only on
those items listed above. (The addendum can be obtained from the SNAP
program, or EPA's Stratospheric Ozone Protection Hotline.)
The completed PMN form (EPA Form 7710-25) will remain the basis for
all information needed to complete review of the new chemical under
section 5 of TSCA. The completed PMN form and the SNAP addendum
together will comprise the data submission for section 612 review and
listing decisions for new chemicals. This approach is intended to
minimize the reporting burden on submitters.
The Agency will modify the PMN Instructions Manual to provide more
explicit direction on how to complete the SNAP addendum. A SNAP
submitter may also consult the SNAP Guidance Manual, which is available
from the Stratospheric Ozone Protection Hotline. Any questions
regarding the completion of these forms can be directed to either the
PMN Pre-notice Coordinator or the SNAP program.
b. Submission of completed forms. Both the PMN and SNAP programs
have a review period of 90 days, subject to suspensions and extensions
described in section VII.A. for the SNAP program and in the PMN final
rule (40 CFR 720.75). To ensure that new chemical submissions are
reviewed and decided on jointly, the Agency encourages submitters to
provide both the PMN form and SNAP addendum to the PMN and SNAP
coordinators. Failure to provide both programs with the requested
information at the same time could result in delays in the review of a
submitter's notice seeking acceptance of a new chemical as a class I or
II substitute concurrent with review under the PMN program.
c. Procedures for handling confidential business information. The
Agency recognizes that, where appropriate, information submitted to the
PMN and SNAP programs may need to be held confidential. EPA has
determined that all CBI submitted as part of the joint PMN/SNAP review
should be maintained and treated in a manner consistent with TSCA
security procedures. Confidentiality claims will be processed and
reviewed in a manner consistent with 40 CFR part 2, subpart B. This
approach was selected because the majority of data provided to SNAP
under the joint review process will come from the PMN form. Submitters
should note that while TSCA and CAA may have different language
describing CBI handling procedures, there is no substantive difference
in how CBI is maintained under the two statutes.
3. Agency Review of New Substitutes under PMN and SNAP
a. Preparation of public docket and Federal Register notices. Once
the letter of receipt has been issued, the PMN program will prepare a
public docket and Federal Register notice, as described in the final
rule for the PMN program (40 CFR 720.75). The PMN program manager will
consult with the SNAP program in preparing the notice.
b. Joint review process. EPA will complete joint evaluations of new
chemicals serving as class I or II substitutes under section 5 of TSCA
and section 612 of the CAA. This joint review process will be
coordinated to ensure that there is consistency in the final decisions
made under the PMN and SNAP programs. To ensure agreement in the
decisions, EPA offices will work in concert to develop toxicity,
exposure, and risk profiles for those substitutes and applications that
come under joint TSCA and CAA review authority. The Agency will also
coordinate its review of the completeness of the information supplied
and any subsequent data requests to minimize the reporting burden on
the submitter. Submitters should note that Agency decisions to restrict
production of particular chemicals under TSCA will, in the case of
joint PMN/SNAP applications, also have the effect of restricting
production of substitutes undergoing review under the SNAP program.
However, companies that produce substitutes only being reviewed under
the SNAP program are not required to cease production during the SNAP
review period in the case of existing substitutes, and in the case of
new substitutes, manufacturers may introduce the substitute into
interstate commerce 90 days after submitting their complete
notification to EPA.
As part of the review, the PMN and SNAP programs will work to
arrive at a consistent decision regarding the new chemical under
review. Consequently, listing decisions under SNAP will reference any
conditions also incorporated into the PMN review (e.g., submission of
additional toxicity information, restrictions on use, etc.).
If a substitute meets the conditions for general PMN approval but
not for SNAP acceptability, the company may produce and market the
substance in question once the 90-day period has elapsed. However, EPA
will commence a rulemaking to prohibit the use of the substitute as a
class I or II substitute. If the chemical fails to meet the conditions
for PMN approval, the submitter is barred from producing the chemical
and consequently is effectively barred from marketing the product as a
substitute for a class I or II compound. Submitters should note,
however, that CAA section 612 places considerable emphasis on
identifying and promoting the use of substitutes which, relative to
others, reduce overall risks to human health and the environment. To
the extent a substitute offers such risk reduction, EPA will make every
effort to facilitate production and use of that alternative.
c. Communication of decision. The PMN program will use the existing
TSCA regulatory framework for communicating decisions on the new
substitute to the submitter. The SNAP program will provide public
notice of decisions regarding the acceptability or unacceptability of a
substitute following the process described in section VII.A.3.g. EPA
will contact the submitter to determine how best to list the substitute
under the SNAP program if necessary to protect the confidentiality of
the alternative.
C. Joint Review of Substitutes under SNAP and FIFRA
1. Background on Use of Ozone-Depleting Chemicals in Pesticides
Certain pesticides are formulated with class I and II chemicals.
Examples include the use of methyl chloroform (1,1,1-trichloroethane)
as an inert ingredient, or the use of methyl bromide as an active
agent. Pesticide products that contain class I and II compounds must be
reformulated as these chemicals are phased out of production pursuant
to Clean Air Act section 604. This section describes how the Agency
will handle reviews of these changes.
2. Applicability
Any new pesticide or amendment of an existing formulation is
already subject to Agency approval under current provisions of the
Federal Insecticide, Fungicide and Rodenticide Act (FIFRA), Public Law
100-460, 100-464 to 100-526, and 100-532. However, as of the effective
date of the SNAP program, new pesticides or formulation changes based
on class I or class II substitutes will also be subject to review under
section 612 of the CAA. These authorities apply in all cases where a
manufacturer amends a pesticide product to replace chemicals being
phased out under CAA section 602 or 604. Similarly, registrations of
new pesticide products will also be subject to SNAP review if the new
formula contains chemicals functionally replacing class I or class II
compounds which would otherwise have been used in the new pesticide
formulation.
3. Review Responsibilities Under FIFRA and CAA/SNAP
In general, review responsibilities for pesticide products under
the CAA SNAP program will focus on a substance's ozone depletion and
global warming potential. The FIFRA reviews will address factors
commonly examined during pesticide amendments and registrations. The
two program offices responsible for these reviews will coordinate their
efforts at critical junctures and share pertinent data to ensure
appropriate technical consideration of the substitute.
4. Data Submission Requirements and Process
a. Preparation of applications. The Agency has reviewed the data
submission needs for the SNAP and FIFRA pesticide amendment/
registration process and found no significant overlap. Because there is
so little overlap, the Agency requires that a submitter requesting
review under both SNAP and the Office of Pesticide Programs' (OPP)
pesticide amendment/registration process submit all information
ordinarily required for the OPP process as well as a fully completed
SNAP information form. A copy of the FIFRA form should be submitted to
OPP, and a copy of the SNAP form should be submitted to the SNAP
Coordinator. The SNAP form can be obtained from the SNAP program. For
further guidance, SNAP submitters may also consult the SNAP Guidance
Manual, which is available from the Stratospheric Ozone Protection
Hotline.
If a registrant is submitting an amendment to a product
registration under FIFRA that currently contains a class I or II
substance, he or she should note in section II (``Amendment
Information'') of the FIFRA form that the amendment was filed in
response to the CAA production phase-out. Similarly, if a registrant is
submitting an application for a new pesticide registration that would
otherwise have been based on a class I or II compound, he or she should
note in Section II of the FIFRA form that the registration includes a
class I or II substitute.
The submitter should also identify in Section II both the
substitute chemical and the class I or II compound it is replacing.
Further, if a registrant is aware that a particular chemical intended
for use as a class I or II substitute in a pesticide formulation has
already been accepted through earlier SNAP/FIFRA determinations, the
registrant should also reference the relevant part of the prior review.
b. Review of applications. When the Agency receives the FIFRA
application and SNAP submission, it will log each into the relevant
tracking systems: the OPP's tracking system for the FIFRA application
and the SNAP tracking system for SNAP submissions. If the FIFRA
application is identified in section II as a Clean Air Act
substitution, the FIFRA program coordinator will contact EPA's SNAP
program to ask if the substitute has been the subject of any prior SNAP
reviews. If the registrant's substitute is already on the list of
unacceptable substitutes, EPA will notify the registrant that the
amendment request cannot be granted. If the registrant's substitute is
already on the list of acceptable substitutes, EPA will proceed with
the standard FIFRA application review. If a chemical substitute is not
listed under existing SNAP determinations but is a substitute for an
ozone-depleting compound, EPA will inform the registrant that a SNAP
review must commence.
5. Communication of Decision
Once EPA review is complete, the Agency will notify the registrant
whether the new formulation or proposed formulation change is
acceptable. At the same time, the Agency will amend the SNAP
determinations to reflect these findings and will publish the revised
determinations in the next quarterly Federal Register notice.
Submitters should note that, because of the shared authority to review
substitutes under both SNAP and FIFRA, formulators may not sell amended
or new formulations subject to FIFRA until they have received FIFRA
approval.
D. Shared Statutory Authority with the Food and Drug Administration
The Federal Food, Drug and Cosmetic Act (FDCA), 21 U.S.C. 321,
provides for the safety and effectiveness of drugs and therapeutic
devices, the purity and wholesomeness of foods, and the harmlessness of
cosmetics. Under this statute, the Food and Drug Administration (FDA)
regulates the packaging of food products and incidental additives and
requires predistribution clearance of medical devices.
As defined in the FDCA, medical devices can include any devices,
diagnostic products, drugs, and drug delivery systems. Devices covered
under this jurisdiction are subject to review under the FDCA. Some
medical devices and food packaging currently contain class I or II
compounds. The Agency has determined that such products are exempt from
further review for human health effects under the SNAP program where
FDA approval of such effects is required before a product can be
introduced into commerce. EPA will rely in its SNAP determination on
FDA's conclusions regarding health effects. The Agency believes this
exemption is justified because of the higher burden of proof placed on
submitters under the FDCA. However, the Agency will continue to
evaluate all other environmental effects of the proposed substitute,
and will consult with the FDA to determine the appropriate course of
action.
VIII. Petitions
A. Background
1. Role of Petitions
Section 612(d) of the CAA explicitly states that ``any person may
petition the Administrator to add a substance * * * or to remove a
substance from either of such (prohibited or safe use) lists.'' The
petition provision serves two principal needs. The first is to permit
the appeal of existing Agency determinations under the SNAP program.
The second is to provide a mechanism for individuals and organizations
to bring to the Agency's attention new information on substitutes that
could affect existing listing determinations or result in new ones.
The opportunity for outside parties to comment on existing listing
decisions is an important aspect of the petition process. As discussed
in the section on notifications, companies that produce substitutes
must submit specific data on the substitutes to the Agency for review.
However, organizations and private citizens other than those required
to submit SNAP notices may have additional information about existing
substitutes or information on new substitutes not yet reviewed by the
Agency. To ensure that the SNAP determinations are based on the best
information on substitutes, it is essential that the Agency offer a
means for such information to be incorporated into the SNAP analyses on
a continuing basis.
Before individuals, organizations, or companies may initiate legal
action against EPA for the purpose of changing the lists of acceptable
or unacceptable substitutes, they must first exhaust all administrative
remedies for receiving such relief, including remedies like the
petition process described in this section.
2. Types of Petitions
Five types of petitions exist:
(1) Petitions to add a substitute not previously reviewed under the
SNAP program to the acceptable list;
(2) Petitions to add a substitute not previously reviewed under the
SNAP program to the unacceptable list;
(3) Petitions to delete a substitute from the acceptable list and
add it to the unacceptable list or to delete a substitute from the
unacceptable list and add it to the acceptable list;
(4) Petitions to add or delete use restrictions on an acceptability
listing, and
(5) Petitions to grandfather general use of an unacceptable or
acceptable subject to narrowed use limits in specified applications
substitute.
Petitioners should note that the first type of petition is
comparable to completing a SNAP submission, except that the latter is
submitted by substitute producers prior to the introduction into
interstate commerce of the substitute for a significant new use as a
class I or II substitute. The first type of petition, by contrast,
would generally be initiated by entities other than the company
responsible for producing the substitute. Companies that manufacture,
formulate, or use a substitute themselves and want to have their
substitutes added to the acceptable list should submit information on
the substitute under the 90-day advance notification review program.
3. Basis for Petition
A petitioner may submit a petition for several reasons, including:
Availability of new information on substitutes or
applications not covered in the existing SNAP determinations;
Requests to extend effective date for existing
prohibitions on uses of an unacceptable substitute;
New technologies or practices that reduce exposures to a
substitute previously unacceptable under SNAP due to toxicity concerns;
or
Requests for acceptability subject to narrowed use limits
listing for specialized applications within a sector end-use for an
unacceptable substitute where no other technologically viable
substitute can be found.
All of the above are examples of valid justifications for
submitting a petition. Other bases for petitioning the Agency may exist
as well, and all petitions with adequate supporting data will receive
consideration under the SNAP program.
4. Nature of Response
The Agency will only review and grant or deny petitions based on
the sector and end-use application identified in the petition. For
example, simply because the Agency ultimately deletes a substitute from
the list of acceptable substitutes for a particular end-use in the
solvents cleaning sector does not mean the substitute is unacceptable
for any specific end-use as a refrigerant. A similar caveat applies for
petitions on applications within a sector. If a substitute, for
instance, is found acceptable for a specific end-use within an
application, it will not automatically be deemed acceptable for any
other end-use in that sector.
B. Content of the Petition
The Agency requires the following information: A brief statement
describing the type of petition, substitute, sector and end-uses to
which it applies; and a brief summary of the basis for the petition and
the data that support the petition. As with SNAP submissions, the
Agency will issue a determination letter on the completeness of the
petition to the petitioner within 15 calendar days of its receipt.
Petition types (1) and (2) must contain the information described
in section V.B. of this notice, which lists the items to be submitted
in a 90-day notification. Information requirements for such petitions
and 90-day notifications are the same, since the Agency will be
applying the same level of analysis to petitions submitted by outside
parties as to notifications received from the producing companies
themselves. For petition types (3) and (4), which request a
reexamination of a substitute previously reviewed under the SNAP
program, the submitter may reference the prior submission rather than
submit duplicate information. In this case, the petitioner should
provide and submit as appropriate any new or additional data. Petitions
to grandfather use of an unacceptable substitute must describe the
applicability of the four-part test to judge the appropriateness of
Agency grandfathering as described in section VI.B. of this final rule.
C. Sufficiency of Data
Petitioners should be aware that insufficient data may prevent the
Agency from reaching a timely decision on whether to grant or deny a
petition. EPA will conclude a completeness review of each petition
received within fifteen days of receipt of the petition. Within the 15-
day period, EPA will inform the petitioner of any additional
information needed. If EPA makes no such request, then after the 15-day
period is completed, the 90-day review period will automatically
commence. If EPA does request any additional data, the 90-day period
shall not commence until the additional data are received and
themselves reviewed for completeness.
As provided in section 612(d), any petition must ``include a
showing by the petitioner that there are data on the substance adequate
to support the petition.'' Petitioners may provide citations to
scientific literature, where appropriate. However, submitters are
advised that furnishing copies of supporting articles, reports, or
letters will expedite the review process.
If the Agency receives a petition with insufficient data, EPA will
not commence review until the petitioner submits the missing
information to the best of the petitioner's ability. EPA will inform
the petitioner when the petition is complete for purposes of initiating
the 90-day review period. To the extent the petitioner does not have
the required information, EPA may also seek data from sources other
than the petitioner, including manufacturers or users of products that
contain the substitute. In such cases, section 612(d) explicitly
provides that ``the Administrator shall use any authority available to
the Administrator, under any law administered by the Administrator, to
acquire such information.'' These authorities include section 114 of
the CAA as well as information collection provisions of other
environmental statutes. Where EPA cannot obtain sufficient data within
the statutory 90-day review period, the Agency may deny the petition
for lack of adequate technical support.
D. Criteria for Evaluating Petitions
In evaluating petitions, the Agency will follow the same criteria
as for review of the SNAP Information Notice which notifies EPA of the
intent to introduce a substitute into interstate commerce. This will
ensure that both petitions and notifications are judged by the same
standards.
E. Petition Review Process
1. Petition Submittal
This final rule describes a generic petition process. Petitions
should be sent to the docket number listed in the beginning of this
final rule as well as to the SNAP Coordinator.
2. Petition Reviews
When the Agency receives a petition, it will log the petition into
the SNAP tracking system. If the petition concerns a substitute
previously either found acceptable or unacceptable under the SNAP
program, the Agency will as a courtesy contact the initial submitter of
that substitute.
The Agency will grant or deny the petition within 90 days of
receiving a complete application. If the Agency grants a petition to
add a substitute to the list of unacceptable substitutes or to remove a
substitute from either list, the decision will be made through notice
and comment rulemaking. In such cases, the statute requires EPA to
propose, take comment on, complete final action, and publish the
revised lists within six months of the grant of the petition.
Otherwise, responses to petitions, including explanations of petition
denials, will be included in the next 3-month Federal Register notice
updating the SNAP determinations. Regardless of the final
determination, the Agency will inform petitioners within 90 days
whether their request has been granted or denied.
IX. Listing of Substitutes
A. Overview
This section presents EPA's listing decisions for class I
substitutes in the following industrial sectors: Refrigeration and air
conditioning, foam blowing, solvents cleaning, fire suppression and
explosion protection, sterilants, aerosols, tobacco expansion and
adhesives, coatings and inks. Parts D through K below present a
detailed discussion of the substitute listing determinations for each
of the major use sectors. Tables that summarize listing decisions in
this section are included in appendix B. Listings of substitutes within
the pesticides sector will be added in future notices, as information
on these substitutes becomes available to the Agency. This final rule
focuses on substitutes for class I substances, given the accelerated
production phaseout schedule for class I substances. One of the goals
of SNAP is to encourage transition away from class I substances as
rapidly as possible. SNAP will begin analyzing alternatives to class II
substances in the near future. Results of these analyses will appear in
quarterly updates to the SNAP lists, which will be published in the
Federal Register as described in Sections III.C.4. and VII.A.3.g. of
this final rule.
To develop the lists of unacceptable and acceptable substitutes,
EPA conducted screens of health and environmental risks posed by
various substitutes for class I compounds in each use sector. These
screens are presented in individual background documents entitled
``Risk Screen on the Use of Substitutes for Class I Ozone-Depleting
Substances'' for each use sector. These background documents are
available for review in the public docket supporting this rulemaking.
Whenever the initial risk screen indicated a potential risk, the
substitute was evaluated further to ascertain whether the potential
risk was accurately estimated and if management controls could reduce
any risk to acceptable levels.
Based on these analyses, EPA classified as unacceptable only uses
of substitutes that pose significantly higher human health and
environmental risks than those risks that would accrue through either
continued use of the class I substances themselves or through use of
other available substitutes.
The assessments presented in the background documents are screens
of the comparative risks posed by use of substitutes, not assessments
or rankings of the absolute risks associated with use of each
substitute. Designating a substitute as acceptable does not imply the
absence of risks for that substitute, but rather that the substitute in
question is believed to present lower overall risks than both the class
I compound it is replacing and other substitutes available for the same
end-use. For instance, in some cases, ozone-depleting substances can be
replaced by chemicals with known toxicity or ability to contribute to
ground-level ozone formation. The Agency's risk screen analyzes these
effects, and the SNAP determinations generally describe as acceptable
those substitutes for which risks from replacements would be lower on
an overall basis compared to risks from other existing alternatives, or
for which such risks could be managed by developing and implementing
appropriate regulatory controls. Additionally, in cases where the
Agency has listed a substitute as unacceptable, it has assessed--as
required in section 612--the availability of other substitutes and
concluded that alternatives with reduced overall risk are currently or
potentially available.
As a rule, the Agency did not evaluate the technical performance of
a substitute, since the purpose of the SNAP program is to examine
environmental effects of substitutes identified as being of commercial
interest regardless of technical acceptability. However, in certain
sectors, performance of the substitute does pertain directly to
environmental or health effects. For example, in refrigeration, the
ability of a refrigerant replacement to serve as a coolant will
directly influence the substitute's energy efficiency, which in turn
will affect the substitute's environmental effects. Similarly, in fire
suppression, the ability of a substitute to put out fires and thereby
save human lives will directly affect a substitute's health effects.
Further, in the case of narrowed use listings, the Agency's decision to
grant or deny a narrowed use petition may hinge on the ability of
potential substitutes to meet technical performance criteria. For
example, in the case of certain specialized solvents, some substitutes
otherwise considered unacceptable may require special consideration
because they are the only available substitute offering performance
characteristics deemed essential in a certain application. In cases
such as these, the SNAP analyses do consider the performance of a
substitute as necessary.
EPA's evaluation of each substitute in an end use is based on the
following types of information and analyses:
Atmospheric effects are assessed by predicting ozone
depletion and analyzing total global warming potential, including
chemical properties relevant to global warming. Ozone depletion is
based on market penetration of a substitute and is measured in terms of
cumulative Clx loadings and its effect in terms of increased
incidence of skin cancer cases and skin cancer mortalities. Analysis of
total global warming potential includes changes consideration of
inherent properties such as atmospheric lifetime and absorption
spectra, as measured by the GWP index, and from changes in fossil fuel
use due to increases or decreases in energy efficiency resulting from
production or use of the substitutes. Atmospheric lifetime is
considered as an indicator of the likely persistence of an
environmental effect or of the time lag to reverse any known or unknown
effect associated with an emission. The model used by the Agency to
determine atmospheric effects--the Atmospheric Stabilization Framework
model--has been used by the Agency in calculating the benefits from the
phase-out of class I substances. The model was peer-reviewed in
connection with this earlier analysis.
Although scientific studies have pointed to the possibility of
ecological effects due to ozone depletion, such as crop damage, the
scope of existing studies is limited and therefore these effects were
not part of this analysis.
Exposure assessments are used to estimate concentration
levels of substitutes to which workers, consumers, the general
population, and environmental receptors may be exposed, and over what
period of time. These assessments are based on personal monitoring data
or area sampling data if available. Otherwise, exposures are assessed
using measured or estimated releases as inputs to mathematical models.
Exposure assessments may be conducted for many types of releases,
including releases in the workplace and in homes, releases to ambient
air and surface water, and releases from the management of solid
wastes.
Toxicity data are used to assess the possible health and
environmental effects from exposure to the substitutes. If Occupational
Safety and Health Administration (OSHA)-approved or EPA-wide health-
based criteria such as Permissible Exposure Limits (PELs, for
occupational exposure), inhalation reference concentrations (RfCs, for
noncarcinogenic effects), or cancer slope factors (for carcinogenic
risk) are available for a substitute, exposure information is combined
with this toxicity information to explore any basis for concern.
Otherwise, toxicity data are used with existing EPA guidelines to
develop health-based criteria for interim use in these risk
characterizations.
Flammability is examined as a possible safety concern for
workers and consumers. EPA assesses flammability risk using data on
flash point and flammability limits (e.g., OSHA flammability/
combustibility classifications), data on testing of blends with
flammable components, test data on flammability in consumer
applications conducted by independent laboratories, and information on
flammability risk minimization techniques.
Some of the substitutes are volatile organic compounds
(VOCs), chemicals that increase tropospheric air pollution by
contributing to ground-level ozone formation. Local and nationwide
increases in VOC loadings from the use of substitutes is also
evaluated.
In conducting these assessments, EPA made full use of previous analyses
performed by the Agency, including EPA's 1990 interim hazard
assessments and supporting documentation. These analyses were modified
in some cases to incorporate more recent data, such as data received in
public comment on the May 12, 1993 NPRM, or to accommodate different
analytical approaches as needed. Finally, these analyses assume that
the regulated community complies with applicable requirements of other
statutes and regulations administered by EPA (e.g., recycling
requirements promulgated under the CAA) and other Federal agencies
(e.g., any occupational exposure limits set by OSHA).
Acceptable substitutes within specific use sectors may be listed as
hazardous wastes or, because of flammability, corrosivity, reactivity
or toxicity characteristics, must be managed as hazardous wastes. The
regulatory status of three chlorinated hydrocarbons (trichloroethylene,
methylene chloride, perchloroethylene) which could serve as substitutes
for ODCs are highlighted in section IX. of this final rule. However,
other chemicals listed as acceptable substitutes are also RCRA-
regulated, and the RCRA regulations should be consulted when
application of a specific substitute for an ozone-depleting substance
is being considered.
Should additional data become available that would help
characterize the risks of substitutes, the Agency will incorporate this
data into its risk screens. For example, the risk screen does not at
present include assessment of the environmental transformation products
of substitutes. Research efforts of the Agency in cooperation with the
Alternative Fluorocarbons Environmental Acceptability Study (AFEAS) are
in progress and are intended to define the chemical, biological and
photochemical sinks for these substances in the biosphere. Ultimately,
these research activities will contribute to the development of more
complete ecological risk assessments for substitutes. However, the
Agency generally does not believe that a more detailed characterization
of risks would lead to a different listing decision for individual
substitutes unless effects are characterized as highly severe, since
the critical comparison for policy purposes remains the adverse effects
posed by continued use of a class I compound.
The listing of acceptable and unacceptable substitutes under SNAP
will continue. Thus, if a company is not yet able to provide the Agency
with the information needed to complete a review of a substitute, a
review can be completed in the future, when data become available. Once
the data are complete, Agency review will begin, as discussed in
sections IV. through IX. of this final rule.
B. Format for SNAP Determinations
Sections IX.D. through IX.K. below present the decisions on
acceptability of substitutes that EPA has made based on available
information and the evaluation criteria (see Section V of this final
rule). These sections describe the sector end-uses (e.g., industrial
process refrigeration), the substitutes evaluated, the decision (i.e.,
acceptable or unacceptable) and associated rationale, any conditions
for or limitations on the use of a substitute, and any general
comments.
In most cases, the end-use descriptions have been written broadly
to encompass numerous industrial applications or uses. Based on
discussions with industry, the Agency felt that this approach was
preferable to listing substitutes by narrowly-defined applications,
which would increase needlessly the number of SNAP notices that would
be received by the Agency. The objective of section 612 is to ensure
that replacement of class I and II substances with available
substitutes will reduce adverse effects on human health and the
environment. In general, the Agency can look at exposures from very
broad classifications of use (e.g., metals cleaning) and perform the
screening analysis to ensure that this statutory objective is being
met. It is not necessary or helpful, for example, to list acceptable
substitutes by each specific type of metal being cleaned in the
solvents cleaning sector. This is especially true when conservative
assumptions used in the screening analysis demonstrate the
acceptability of an alternative in a wide range of end-uses. Where
possible, the substitutes presented in sections D. through K. have been
identified by their chemical name. Generally speaking, EPA has not
listed substitutes by product or company name in order to avoid implied
endorsement of one substitute over another. However, there are two
circumstances in which specific chemical names have not been included.
First, where proprietary blends have been identified as substitutes,
the Agency has worked with the manufacturers to identify generic ways
in which the substitute could be listed. Before a user invests in a
substitute in these categories, they may wish to contact the SNAP
program to confirm that the specific substitute they intend to use has
been reviewed and found acceptable by EPA. EPA believes that if a
potential user identifies the substitute by a product name that EPA has
on record, but was not included on the list for the reasons stated
above, EPA can confirm the listing of the substitute without violating
safeguards important to protect any proprietary business information
provided in confidence to the Agency.
The second situation in which EPA does not anticipate listing
specific chemicals arises in the solvents cleaning sector, primarily
for aqueous and semi-aqueous cleaners. In this area, numerous cleaning
formulations exist and are comprised of a wide variety of chemicals. As
discussed in the section below on solvents cleaning alternatives (see
section IX.F.), the Agency performed its screening assessment by
identifying representative chemicals. These were then used to screen a
wide variety of chemicals grouped into categories of solvent-cleaning
constituents (e.g., saponifiers, surfactants, etc.). Information on
these chemicals presented in the risk screen was used as a basis for
determining that aqueous and semi-aqueous cleaners present lower risk
than the chemicals they are replacing.
EPA has selected this strategy for listing as acceptable aqueous
and semi-aqueous cleaners for several reasons. First, it should
minimize the need to submit SNAP notices for blends of compounds that
are combinations of the chemicals which have already been approved.
Second, it will allow EPA to avoid listing proprietary formulations.
Any conditions for use included in listing decisions are part of
the decision to identify a substitute as acceptable. Thus, users would
be considered out of compliance if using a substitute listed as
acceptable without adhering to the conditions EPA has stipulated for
acceptable use of the alternative. Alternatively, where restrictions
are set which narrow the acceptable applications within an end-use, a
user would be considered out of compliance if using the compound in an
end-use application where such use is unacceptable. Conditions, if any,
are listed when it is clear that a substitute can only be used safely
if certain precautions are maintained. As noted previously, any
conditions will be imposed in the listing of substitutes as acceptable
through rulemaking.
The comments contained in the table of listing decisions found in
summary form in Appendix B provide additional information on a
substitute. Since comments are not part of the regulatory decision,
they are not mandatory for use of a substitute. Nor should the comments
be considered comprehensive with respect to other legal obligations
pertaining to the use of the substitute. However, EPA encourages users
of acceptable substitutes to apply any comments in their use of these
substitutes. In many instances, the comments simply allude to sound
operating practices that have already been identified in existing
industry and/or building-code standards. Thus, many of the comments, if
adopted, would not require significant changes in existing operating
practices for the affected industry.
C. Decisions Universally Applicable
Recently, the Agency has become aware of substitute mixtures that
are being marketed as replacements for both class I and II chemicals.
In situations where these mixtures are a combination of class I and II
chemicals, they may serve as transitional chemicals because they offer
environmental advantages in that they have a lower combined ODP than
use of a class I compound by itself. However, where EPA has identified
a non-ozone depleting alternative that reduces overall risk to human
health and the environment, mixtures of class I and II substances shall
be unacceptable or subject to use limits.
There have been a few instances in which mixtures of class I and II
chemicals have been marketed as replacements for class II chemicals.
Because the ODP of such alternatives is clearly higher than the class
II substances, the Agency is prohibiting the use of any class I and
class II mixture as a replacement for a class II chemical. Where the
Agency is aware of specific mixtures falling into this category, they
are listed by individual use sector below. The remainder of this
section presents the initial listing decisions for each of the
following end use sectors:
D. Refrigeration and Air Conditioning
E. Foam Blowing
F. Solvents Cleaning
G. Fire Suppression and Explosion Protection
H. Sterilants
I. Aerosols
J. Tobacco Expansion
K. Adhesives, Coatings and Inks
D. Refrigeration and Air Conditioning
1. Overview
The refrigeration and air conditioning sector includes all uses of
Class I and Class II substances to transfer heat. Most end-uses in this
sector involve mechanically moving heat from a cool region to a warmer
one. For example, a car's air conditioner moves heat from the cooled
interior to the hot ambient air.
This sector also includes heat transfer end-uses, i.e. those uses
of Class I and Class II substances to move heat from a warm region to a
cool one. For example, CFC-114 is currently used to remove excess heat
from a very hot uranium enrichment process to cooler ambient air.
Hence, the process requires no additional energy, and does not create
refrigeration by mechanical means.
Mechanical systems generally use a vapor compression cycle.
However, several alternative cycles have been used for decades; these
and other alternatives are being re-examined in light of the phaseout
of commonly used CFC-based refrigerants in 1996. Substitutes reviewed
under SNAP may use alternative cycles; review is not restricted solely
to applications based on replacing the working fluid in vapor
compression equipment. Similarly, simple heat transfer end-uses will
also be included.
The refrigeration and air conditioning sector is divided into the
following end-uses:
Commercial comfort air conditioning;
Industrial process refrigeration systems;
Industrial process air conditioning;
Ice skating rinks;
Uranium isotope separation processing;
Cold storage warehouses;
Refrigerated transport;
Retail food refrigeration;
Vending machines;
Water coolers;
Commercial ice machines;
Household refrigerators;
Household freezers;
Residential dehumidifiers;
Motor vehicle air conditioning;
Residential air conditioning and heat pumps; and
Heat transfer.
EPA has not necessarily reviewed substitutes in every end-use.
The following discussion provides some distinctions among the
various end-uses in the refrigeration and air conditioning sector.
a. Chillers. CFCs are used in several different types of mechanical
commercial comfort air conditioning systems, known as chillers. These
chillers cool water, which is then circulated through a building. They
can be classified by compressor type, including centrifugal,
reciprocating, scroll, screw, and rotary. The selection of a particular
compressor type generally depends on the cooling capacity required.
Reciprocating and scroll compressors are used in small capacity
applications (less than 200 tons), screw compressors are used in medium
capacity applications (50 to 400 tons), and centrifugal compressors are
used in large capacity applications (greater than 300 tons). The
majority of the chillers used in the United States are centrifugal
chillers. Chillers have a lifetime of 23 to 40 years. EPA anticipates
that over time, existing cooling capacity will be either retrofitted or
replaced by systems using non-CFC refrigerants in a vapor compression
cycle or by alternative technologies.
b. Industrial process refrigeration systems. Many industrial
applications require cooling of process streams. These applications
include systems designed to operate in a wide temperature range.
Included within this category are industrial ice machines and ice
rinks. The choice of substitute for specific applications depends on
ambient and required operating temperatures and pressures.
c. Ice skating rinks. Skating rinks frequently use secondary
refrigeration loops. They are used by the general public for
recreational purposes.
d. Industrial process air conditioning. Ambient temperatures near
200 degrees Fahrenheit and corrosive conditions make this application
distinct from commercial and residential air conditioning. Units in
this end-use provide comfort cooling for operators and protect process
equipment.
e. Uranium isotope separation processing. This end-use includes
operation of a heat transfer cycle to cool uranium isotope separation
processing. Substitutes must meet an extremely rigorous set of criteria
to be applicable in this end-use.
f. Cold storage warehouses. Cold storage warehouses are used to
store meat, produce, dairy products and other perishable goods. The
majority of cold storage warehouses in the United States use ammonia as
the refrigerant in a vapor compression cycle.
g. Refrigerated transport. Refrigerated transport moves products
from one place and climatic condition to another, and include
refrigerated ship holds, truck trailers, railway freight cars, and
other shipping containers. Refrigerated transport systems are affected
by a number of inherent complications not found with other
refrigeration and air conditioning end-uses. In route, the refrigerated
units may be subject to a broad range of ambient temperatures. Engine-
driven transport units suffer power interruptions when either the unit
or the vehicle is out of use for brief periods of time (e.g., loading
and unloading and fuel stops). Refrigerated units are designed to
provide the maximum amount of space available for containment of the
product to be transported. Refrigerated transport equipment must be
versatile to allow for the different temperature requirements for the
different products (e.g., ice cream versus fresh produce) which may be
transported.
h. Retail Food Refrigeration. This end-use includes all cold
storage cases designed to chill food for commercial sale. Equipment in
this end-use is generally designed for two temperature regimes: Low
temperature cases operating below freezing and medium temperature units
merely chilling food. In addition to grocery cases, the end-use
includes convenience store reach-in cases and restaurant walk-in
refrigerators. Icemakers in these locations are discussed under
commercial ice machines.
i. Vending machines. Vending machines are self-contained units
which dispense goods that must be kept cold or frozen. Like equipment
in other end-uses, the choice of substitute will strongly depend on
ambient conditions and the required operating temperature.
j. Water coolers. Water coolers are also self-contained and provide
chilled water for drinking. They may or may not feature detachable
containers of water.
k. Commercial ice machines. These units are used in commercial
establishments to produce ice for consumer use, e.g., in hotels,
restaurants, and convenience stores. Thus, the cleanliness of the ice
is important. In addition, the machines are typically smaller in size
than industrial equipment. Commercial ice machines are typically
connected to a building's water supply.
l. Household refrigerators. Household refrigerators are intended
primarily for residential use, although they may be used outside the
home. Approximately 159 million units exist in the U.S., where the
average residential refrigerator is an 18.4 ft3 automatic defrost
unit with a top mounted freezer. Cooling is provided by a conventional
single evaporator unit in a vapor compression cycle. The evaporator is
located in the freezer compartment, and cooling to both compartments is
typically achieved by mechanically driven air exchange between the
compartments.
m. Household freezers. Household freezers only offer storage space
at freezing temperatures, unlike household refrigerators. Two model
types, upright and chest, provide a wide range of sizes.
n. Residential dehumidifiers. Residential dehumidifiers are
primarily used to remove water vapor from ambient air for comfort
purposes. While air conditioning systems often combine cooling and
dehumidification, this application serves only the latter purpose.
Since air is cooled as it flows over the evaporator, it loses moisture
through condensation. It is then warmed as it passes over the condenser
coil. Dehumidifiers actually slightly warm the surrounding air, since
the compressor adds heat to the cycle.
o. Motor vehicle air conditioning. Motor vehicle air conditioning
systems (MVACS) provide comfort cooling for passengers in cars, buses,
planes, trains, and other forms of transportation. MVACS pose risks
related to widely varying ambient conditions, accidents, do-it-yourself
maintenance, and the location of the evaporator inside the passenger
compartment. Given the large number of cars in the nation's fleet, and
the variety of designs, new substitutes must be used in accordance with
established retrofit procedures.
Flammability is a concern in all applications, but the conditions
of use and the potential for accidents in this end-use increase the
likelihood of a fire. In addition, the number of car owners who perform
their own routine maintenance means that more people will be exposed to
potential hazards. Current systems are not designed to use flammable
refrigerants.
p. Residential air conditioning and heat pumps. HCFC-22, a class II
substance, is the dominant working fluid in residential air
conditioning and heat pumps. This end-use includes both central units
and window air conditioners. SNAP will begin analyzing class II
substance substitutes in the near future. Results of these analyses
will appear in quarterly updates in the Federal Register.
q. Heat transfer. This end-use includes all cooling systems that
rely on convection to remove heat from an area, rather than relying on
mechanical refrigeration. There are, generally speaking, two types of
systems: Systems with fluid pumps, referred to as recirculating
coolers, and those that rely on natural convection currents, referred
to as thermosiphons.
2. Substitutes for Refrigerants
Substitutes fall into eight broad categories. Seven of these
categories are chemical substitutes generally used in the same cycle as
the ozone-depleting substances they replace. They include
hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs),
hydrocarbons, blends of refrigerants, ammonia, perfluorocarbons (PFCs),
and chlorine systems. The eighth category includes alternative
technologies that generally do not rely on vapor compression cycles.
a. Hydrochlorofluorocarbons (HCFCs). EPA believes that
hydrochlorofluorocarbons have an important role to play as transitional
refrigerants. HCFCs are chemically similar to CFCs except that they
contain hydrogen in addition to chlorine and fluorine. Because their
thermophysical properties are, in many cases, similar to CFCs,
equipment designed to use CFCs can often be retrofitted to operate with
HCFCs. In addition, new equipment can be designed specifically for
these compounds.
HCFCs contribute to the destruction of stratospheric ozone, but to
a much lesser extent than CFCs. Use of HCFCs as transitional
refrigerants will allow industry to move away from CFCs more rapidly
and, therefore, will offer significant environmental and health
benefits over the continued use of CFCs. Because they contain hydrogen,
the HCFCs break down more easily in the atmosphere than do CFCs, and
therefore have lower ODPs. Their global warming potentials are also
lower than those for the CFCs. Production of HCFCs is controlled under
the international agreement set forth in the Montreal Protocol, which
is being implemented in the U.S. through the Clean Air Act. HCFCs were
initially scheduled to be phased out by 2030. As a result of growing
evidence indicating greater risks of ozone depletion, however, the
international community agreed in Copenhagen in November 1992 to
accelerate the phaseout of the ozone-depleting compounds, including
HCFCs. As a result, EPA published an accelerated phaseout of HCFCs on
December 10, 1993 (58 FR 65018). The proposed accelerated schedule
places production and consumption limits on the most potent ozone-
depleting HCFCs first, with the production of HCFCs with lower ozone
depletion potentials (ODPs) permitted over a longer period of time.
There are clear environmental and health benefits to be gained by
allowing near-term use of HCFCs until substitutes with zero ODP are
developed.
b. Hydrofluorocarbons (HFCs). Hydrofluorocarbons do not contain
chlorine and do not contribute to destruction of stratospheric ozone.
However, some HFCs do have significant global warming potentials
(GWPs). Although a few HFCs have been in use for some time, the
potential for HFCs as a replacement for CFCs has grown rapidly over the
last several years. EPA is concerned that rapid expansion of the use of
some HFCs could contribute to global warming. Nonetheless, HFCs as a
class offer lower overall risk than continued use of CFCs, as well as a
near-term option for moving away from CFCs.
c. Hydrocarbons. Hydrocarbons do not contain chlorine or bromine;
they therefore also have zero ODP. Hydrocarbons degrade in the lower
atmosphere, contributing to ground-level pollution such as smog, but
they do not contribute directly to global warming. Propane, ethane,
propylene, and to some extent butane are used as refrigerants in
specialized industrial applications, primarily in oil refineries and
chemical plants, where they are frequently available as part of the
process stream and where their use contributes only a slight increment
to the overall risk of fire or explosion. Because of the overall risks,
these systems are designed to meet rigid requirements for reliability,
durability, and safety.
Hydrocarbon refrigerants are also used in some home appliances. In
general, they are effective refrigerants and may provide some gains in
efficiency over CFCs. EPA believes refrigeration end-uses may exist for
this class of compounds, but such determinations will require analysis
of appropriate controls to address the risk of fire.
d. Blends. Blends of refrigerants offer significant opportunities
for alternatives to class I substances. The number of single-substance
substitutes is limited; combinations greatly expand the number of
possible refrigerants. By varying the concentrations of the
constituents, manufacturers may design blends for specific end-uses.
Blends generally fall into two categories: azeotropes and
zeotropes. Azeotropes behave like single refrigerants under normal
conditions. They boil and condense at constant temperature and do not
change composition across a phase change. Zeotropes, however, exhibit
temperature glide, meaning that as the refrigerant flows across a heat
exchanger, the temperature changes in response to differential boiling
or condensing of different constituents in the blend. Known as
fractionation, this process may pose additional risks if any of the
blend's components are flammable, even if the blend as formulated is
not. On the other hand, equipment designed to take advantage of
zeotropic blends may reap energy efficiency gains. EPA expects blends
to play an important role in the transition away from ODSs.
In some cases, the specific components of blends, as well as their
proportions, are confidential business information; in others, only the
proportions are confidential. With respect to both types of blends,
however, listings in this final rule and in future updates will refer
to only those blends which have been submitted for review. Although
several companies may submit blends with the same components, only
those compositions specifically reviewed under SNAP will be listed as
acceptable. ASHRAE has issued numerical designations for many blends.
All blends will be assigned a generic name for use in public notices.
Substitutes that were included in the proposed rule will retain the
same generic names, but the listing will include any available ASHRAE
designations. Blends submitted since the proposed rule will be listed
using the ASHRAE designation when available. If ASHRAE has not issued
its designation, they will be assigned new names. In most cases, the
discussion in the listings will include the blends' components. Blends
that contain HCFCs will be labeled ``HCFC Blend Alpha'', ``HCFC Blend
Beta'', etc. This designation is intended to ease identification of
blends which must be handled in accordance with other regulations
described below. Blends that have zero ODP will be given similar names
that describe their major components. An information sheet listing the
trade names and manufacturers of the blends, along with a vendor list,
may be obtained by contacting the SNAP refrigerants sector expert.
e. Ammonia. Ammonia has been used as a medium to low temperature
refrigerant in vapor compression cycles for more than 100 years.
Ammonia has excellent refrigerant properties, a characteristic pungent
odor, no long-term atmospheric risks, and low cost. It is, however,
moderately flammable and toxic, although it is not a cumulative poison.
OSHA standards specify a 15 minute short-term exposure limit of 35 ppm
for ammonia.
Ammonia is used as the refrigerant in meat packing, chicken
processing, dairy, frozen juice, brewery, cold storage, and other food
processing and industrial applications. It is also widely used to
refrigerate holds in fishing vessels. Some absorption refrigeration and
air conditioning systems use ammonia as well.
f. Perfluorocarbons. Unlike CFCs, HCFCs or HFCs, perfluorocarbons
(PFCs) are fully fluorinated compounds. The principal environmental
characteristic of concern for these compounds is that they have
extremely long atmospheric lifetimes, often orders of magnitude longer
than those of the CFCs. These long lifetimes cause the PFCs to have
very high global warming potentials. Technology for containment and
recycling of PFCs is commercially available and is recommended by
manufacturers to offset any possible adverse environmental effects.
One advantage of the PFCs is that, like HFCs, they do not
contribute to ozone depletion. In addition, these chemicals are
nonflammable and exhibit low toxicity, and they are not subject to
federal regulations concerning volatile organic compounds (VOCs), since
they do not contribute to ground-level ozone formation.
The Agency anticipates that in widespread use, these compounds pose
higher overall risk compared to other available alternatives because of
their relatively long lifetimes and associated high GWPs. Because of
these concerns, the Agency has found acceptable only certain narrowly
defined uses of perfluorinated compounds, prohibiting their use where
other alternatives with lower overall risk are available. EPA has
described these limited acceptable uses as specifically as possible.
Further, users should be aware that, because of the environmental
concerns detailed above, any proposed uses of PFCs outside those
described in this final rule should be submitted for future review
under SNAP.
g. Chlorine. Chlorine was listed in the proposed regulation as an
alternative refrigerant in chlorine liquefaction, a processing step in
the manufacture of the chemical. When chilled below its boiling point,
chlorine can be stored as a liquid at atmospheric pressure, a method
that for safety reasons is preferable to storing the chemical as a
pressured gas at ambient temperatures. Although the refrigeration
system will generally be physically separate from the actual chlorine
process stream, compatibility of the refrigerant with liquid chlorine
is critical because of chlorine's high reactivity. CFC-12 has been
widely used because it does not react with chlorine.
Systems using chlorine as a refrigerant require specialized
compressors designed to resist chemical attack by liquid and gaseous
chlorine. EPA has determined that chlorine can be safely used in
refrigeration systems associated with chlorine-containing industrial
process streams. Such systems must be designed and operated with the
same safety considerations that apply to the process stream. In
particular, OSHA regulates this use under its standard for Process
Safety Management of Highly Hazardous Chemicals (29 CFR 1910.119).
h. Alternative technologies. Several technologies already exist as
alternatives to equipment using class I substances. As a result of the
CFC phaseout, they are gaining prominence in the transition away from
CFCs. Examples of these technologies include evaporative cooling,
desiccant cooling, and absorption refrigeration and air conditioning.
In addition, several technologies are currently under development.
Significant progress has expanded the applicability of these
alternatives, and their environmental benefits generally include zero
ODP and low direct GWP. In addition, evaporative cooling offers
significant energy savings, which results in reduced indirect GWP.
3. Comment Response
a. Comments on acceptable substitutes. A commenter opposed listing
the use of HCFC-123 as acceptable because of toxicity concerns. EPA has
conducted worker exposure studies which indicate that exposure can be
limited to 1 ppm, substantially below the industry-established
acceptable exposure limit (AEL) of 30 ppm. Based on these studies, EPA
remains confident that HCFC-123 can be used safely when standard
industrial hygiene practices are followed. It is important to note,
too, that the AEL is a long-term exposure limit. Safety measures to
limit short-term exposures are important for all refrigerants.
Another commenter informed EPA that chlorine-based refrigeration
systems are generally physically separated from chlorine-containing
process streams. This separation invalidates the analogy to
hydrocarbon-based systems for industrial process refrigeration. Hence,
EPA's final determination that chlorine is acceptable for this end-use
includes the acknowledgement of OSHA standards dictating safety
considerations in the design and operation of such systems.
b. Other comments. Several commenters requested additional end-use
categories, while others requested greater aggregation. Some
aggregation is necessary to minimize confusion and the analysis of
small differences among similar applications. Yet EPA also recognizes
that certain end-uses are fundamentally different from others. In the
NPRM, EPA identified major end-uses within the refrigeration and air
conditioning sector. For purposes of the final rule, EPA is reluctant
to change the end-use categories from those listed in the proposed
rule. Retaining the original end-uses serves the goal of creating the
certainty needed to encourage transition away from ozone-depleting
substances.
However, this final rule does combine substitute listings for
various refrigerants within each end-use. For example, industrial
process refrigeration now includes substitutes for CFC-11, CFC-12, and
R-502. The risk screens conducted by EPA analyzed the use of
substitutes within an end-use; the chemical being replaced was usually
not relevant to the analysis. Because it may be important to
distinguish among substitutes for certain substances if they exhibit
significantly different operational characteristics, such as condensing
pressure or typical ambient conditions, the listings do not combine
centrifugal chillers into one end-use. Rather, retrofitted CFC-11, CFC-
12, CFC-113, and CFC-114 chillers remain separate.
A commenter proposed that all blends consisting of individually
acceptable components be deemed acceptable. EPA believes that blends
pose analytical difficulties not encountered with single refrigerants.
Blends, unlike single compounds, have the potential to separate into
components during normal use and during leaks. This process is called
fractionation, and it is caused by differences in vapor pressure among
the constituents.
For example, as a zeotropic blend enters the evaporator, it is a
liquid until it absorbs enough heat to reach the boiling point of the
component with the highest vapor pressure. As this portion boils away,
the remaining components will have a higher overall boiling point, and
the temperature will rise until the second component begins to
vaporize. This process may continue until all the refrigerant is in
vapor phase, or some may remain a liquid even at the exit from the
evaporator. Azeotropes and near-azeotropes, however, exhibit small
changes in temperature in these two-phase parts of the system, and do
not undergo significant composition changes during normal use.
During normal operation, pressure across the condenser and
evaporator remains relatively constant. During a leak, however, system
pressure decreases. In addition, the refrigerant is exposed to ambient
temperatures. As a result, fractionation is possible during a leak when
both vapor and liquid are present, even for azeotropes.
As with all substitutes, flammability and materials compatibility
testing are necessary for blends. For azeotropes, these data are
necessary for the single composition during normal operation. For
zeotropes, such testing is necessary at all compositions occurring
during normal operation. In addition, such tests should be conducted
during multi-phase leaks for all blends to determine the extent and
effects of fractionation. Even if the blend is nonflammable as
formulated, enrichment of a flammable component through fractionation
could result in a flammable mixture. In addition, materials compatible
with the blend as formulated may not retain that compatibility if
fractionation results in a substantially different composition.
Therefore, EPA believes it is not appropriate to automatically find all
blends of acceptable components also acceptable. Only specific
compositions will be designated acceptable, as described earlier.
Several commenters believed EPA was unclear in its distinctions
between new and retrofit substitutes. In response, EPA has clarified
this difference in this final rule. A tension exists between deeming
substitutes acceptable for as wide a range of end-uses as possible and
providing some guidance to users on effective substitutes.
Several commenters suggested duplicating listings for retrofits and
new equipment, but that duplication does not always serve the goal of
disseminating information about viable substitutes. Certain substances
may not be attractive for long-term use because they contain HCFCs, and
thus may only be listed for retrofits. Alternatively, substitutes may
not be easily implemented as a retrofit. It should be noted, however,
that an acceptability determination for use in new equipment or as a
retrofit option does not imply that the alternative is unacceptable for
use in the other category.
The retrofit category within each end-use refers to the use of
substitutes with some modification to existing equipment but without
changing every component. Generally speaking, retrofit refrigerants
will not require completely new systems or redesign. Drop-in
replacements require minimal retrofitting, as in cases where only the
refrigerant needs to be replaced.
The new equipment category within each end-use refers to the use of
substitutes in entirely new systems. No existing components will be
used. This designation may be used for refrigerants which may require
significant design changes. For example, use of a flammable substitute
may require some design changes to mitigate potential risk. Submitters
must demonstrate how those risks can be addressed in new designs. In
addition, alternative technologies often require entirely different
systems. For example, evaporative cooling does not use a vapor
compression cycle, and therefore cannot be used as a retrofit option.
For purposes of submissions, the retrofit and new use categories
should be considered separate end-uses and listed separately on the
submission form.
4. Listing Decisions
a. Acceptable substitutes. These determinations are based on data
submitted to EPA and on the risk screen described in the draft
background document entitled ``Risk Screen on the Use of Substitutes
for Class I Ozone-Depleting Substances: Refrigerants''. In accordance
with the guiding principles for SNAP, substitutes were compared both to
the substance they replace and to each other.
EPA believes the use of all acceptable substitutes presents lower
overall risk than the continued use of an ozone-depleting substance.
Not all substitutes will necessarily be appropriate choices for all
systems within an end-use. Engineering decisions must take into account
factors such as operating temperatures and pressures, ambient
conditions, and age of equipment, especially during retrofits. For
example, under industrial process refrigeration, both HFC-134a and
HCFC-22 are listed as acceptable for retrofits. However, these
substances exhibit significantly different thermodynamic
characteristics, and both may not be appropriate for use within a given
system. EPA believes such decisions are most appropriately made by the
equipment owner, manager, or contractor.
Users of HCFCs should be aware that an acceptability determination
shall not be construed to release any user from compliance with all
other regulations pertaining to class II substances. These include: (a)
The prohibition against venting during servicing under section 608,
which was effective July 1, 1992; (b) recycling requirements under
section 608, which were effective July 13, 1993; (c) section 609
regulations regarding MVACS which were effective August 13, 1992; and
(d) the revised production phaseout of class II substances under
section 606, which was published on December 10, 1993. In addition,
users of non-chlorine refrigerants should be aware that an
acceptability determination shall not be construed to release any user
from conformance with the venting prohibition under section 608(c)(2),
which takes effect November 15, 1995, at the latest.
Substitutes are listed as acceptable by end-use. These substitutes
have only been found acceptable for use in the specific end-uses for
which they have been reviewed, as described in this section. Users of
blends should be aware that EPA has evaluated and found acceptable in
each case only the specific percentage composition submitted for
review; no others have been evaluated. EPA strongly recommends that
users of alternative refrigerants adhere to the provisions of ASHRAE
Standard 15--Safety Code for Mechanical Refrigeration. ASHRAE Standard
34--Number Designation and Safety Classification of Refrigerants is a
useful reference on refrigerant numerical designations. Users are also
strongly encouraged to contain, recycle, or reclaim all refrigerants.
(1) CFC-11 Centrifugal Chillers, Retrofit. (a) HCFC-123. HCFC-123
is acceptable as a substitute for CFC-11 in retrofitted centrifugal
chillers. Because HCFC-123 contributes to ozone depletion, it is
considered a transitional alternative. Since it poses much lower ozone-
depleting risk than continued use of CFCs, EPA has determined that its
use is acceptable for these end-uses. In addition, HCFC-123's GWP and
atmospheric lifetime are significantly lower than almost any other
alternatives. HCFC-123 is not flammable. Since HCFC-123 is classified
as a B1 refrigerant pursuant to ASHRAE standard 34, ASHRAE requires
that a refrigerant vapor detector be placed in the machinery room. EPA
strongly recommends that users of HCFC-123 adhere to this requirement
and any other requirements provided in ASHRAE Standards 15 and 34.
Worker-monitoring studies conducted by EPA demonstrate that HCFC-123's
8-hour time-weighted average concentration can be maintained at or
under 1 ppm (less than the industry-established AEL of 30 ppm),
provided that such standards are followed.
(2) CFC-12 Centrifugal Chillers, Retrofit. (a) HFC-134a. HFC-134a
is acceptable as a substitute for CFC-12 in retrofitted centrifugal
chillers. HFC-134a does not contribute to ozone depletion. HFC-134a's
GWP and atmospheric lifetime are close to those of other alternatives
which are acceptable in this end-use. While HFC-134a is compatible with
most existing refrigeration and air conditioning equipment parts, it is
not compatible with the mineral oils currently used in such systems. An
ester-based lubricant should be used rather than mineral oils.
(3) CFC-113 Centrifugal Chillers, Retrofit. No substitutes have
been identified for CFC-113 in retrofitted centrifugal chillers.
(4) CFC-114 Centrifugal Chillers, Retrofit. (a) HCFC-124. HCFC-124
is acceptable as a substitute for CFC-114 in retrofitted centrifugal
chillers. Because HCFC-124 contributes to ozone depletion, it is
considered a transitional alternative. However, it represents a much
lower ozone-depleting risk than the continued use of CFCs. In addition,
HCFC-124's GWP and atmospheric lifetime are significantly lower than
other alternatives. HCFC-124 is not flammable.
(5) R-500 Centrifugal Chillers, Retrofit. (a) HFC-134a. HFC-134a is
acceptable as a substitute for R-500 in retrofitted centrifugal
chillers. See the discussion on HFC-134a under retrofitted CFC-12
centrifugal chillers.
(6) CFC-11, CFC-12, CFC-113, CFC-114, and R-500 Centrifugal
Chillers, New. (a) HCFC-123. HCFC-123 is acceptable as a substitute for
CFC-11, CFC-12, CFC-113, CFC-114, and R-500 in new centrifugal
chillers. See the discussion on HCFC-123 under retrofitted CFC-11
centrifugal chillers.
(b) HCFC-124. HCFC-124 is acceptable as a substitute for CFC-114 in
new centrifugal chillers. See the discussion on HCFC-124 under
retrofitted CFC-114 centrifugal chillers.
(c) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-11, CFC-
12, CFC-113, CFC-114, and R-500 in new centrifugal chillers. HCFC-22
has been used in a variety of air conditioning and refrigeration
applications for many years. Like HCFC-123, HCFC-22 contributes to
ozone depletion and is considered a transitional alternative. HCFC-22
exhibits a higher ODP than HCFC-123, and production of it will be
phased out according to the accelerated phase out schedule. HCFC-22's
GWP and atmospheric lifetime are higher than other HCFCs. HCFC-22 is
not flammable and is it compatible with existing oils used in most
refrigeration and air conditioning equipment.
(d) HFC-134a. HFC-134a is acceptable as a substitute for CFC-11,
CFC-12, CFC-113, CFC-114, and R-500 in new centrifugal chillers. See
the discussion on HFC-134a under retrofitted CFC-12 centrifugal
chillers.
(e) HFC-227ea. HFC-227ea is acceptable as a substitute for CFC-11,
CFC-12, CFC-113, CFC-114, and R-500 in new centrifugal chillers. HFC-
227ea is a new chemical that has not seen widespread use. It contains
no chlorine, so it does not contribute to ozone depletion. HFC-227ea's
GWP and atmospheric lifetime are higher than those of other
alternatives which are acceptable in this end-use. HFC-227ea is also
being investigated as a component of several blends.
(f) Ammonia. Ammonia is acceptable as a substitute for CFC-11, CFC-
12, CFC-113, CFC-114, and R-500 in new centrifugal chillers. Ammonia
does not deplete the ozone or contribute to global warming. Ammonia is
flammable and toxic, but it may be used safely if existing OSHA and
ASHRAE standards are followed. Users should check local building codes
related to the use of ammonia.
(g) Evaporative cooling. Evaporative Cooling is acceptable as an
alternative technology to centrifugal chillers using CFC-11, CFC-12,
CFC-113, CFC-114, or R-500. Evaporative cooling does not contribute to
ozone depletion or global warming and has the potential to be more
energy efficient than current refrigeration and air conditioning
systems. Evaporative cooling uses no chemicals, but relies instead on
water evaporation as a means of cooling. It is in widespread use in
office buildings in the western U.S. Recent design improvements have
greatly expanded its applicability to other regions.
(h) Desiccant cooling. Desiccant cooling is acceptable as an
alternative technology to centrifugal chillers using CFC-11, CFC-12,
CFC-113, CFC-114, or R-500. Desiccant cooling systems do not contribute
to ozone depletion or global warming. They offer potential energy
savings over the use of CFC-11. Desiccant cooling is an alternate
technology to the vapor compression cycle.
(i) Ammonia/water absorption. Ammonia/water absorption is
acceptable as an alternative technology to centrifugal chillers using
CFC-11, CFC-12, CFC-113, CFC-114, or R-500. Ammonia/water absorption is
an alternative technology to vapor compression cycles. Ammonia is the
refrigerant, and water is the absorber. This alternative has zero ODP
and GWP. For information on toxicity, see the discussion of ammonia
above. Users should check local building codes related to the use of
ammonia.
(j) Water/lithium bromide absorption. Water/lithium bromide
absorption is acceptable as an alternative technology to centrifugal
chillers using CFC-11, CFC-12, CFC-113, CFC-114, or R-500. Some
absorption systems use water as the refrigerant and lithium bromide as
the absorber. Lithium bromide has zero ODP and GWP. It is low in
toxicity and is nonflammable.
(k) Stirling cycle. Stirling Cycle systems are acceptable as an
alternative technology to centrifugal chillers using CFC-11, CFC-12,
CFC-113, CFC-114, or R-500. These systems use a different thermodynamic
cycle from vapor compression equipment. Helium is frequently used as
the refrigerant. The Stirling cycle does not include a phase change.
Heat transfer is accomplished through compression and expansion. These
systems have been used for several decades, primarily in refrigerated
transport and cryogenics.
(7) CFC-12 Reciprocating Chillers, Retrofit. (a) HFC-134a. HFC-134a
is acceptable as a substitute for CFC-12 in retrofitted reciprocating
chillers. See the discussion on HFC-134a under retrofitted CFC-12
centrifugal chillers.
(8) CFC-12 Reciprocating Chillers, New. (a) HCFC-22. HCFC-22 is
acceptable as a substitute for CFC-12 in new reciprocating chillers.
See the discussion on HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-
114, and R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 in
new reciprocating chillers. See the discussion on HFC-134a under
retrofitted CFC-12 centrifugal chillers.
(c) HFC-227ea. HFC-227ea is acceptable as a substitute for CFC-12
in new reciprocating chillers. See the discussion on HFC-227ea under
new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(d) Evaporative cooling. Evaporative Cooling is acceptable as an
alternative technology to reciprocating chillers using CFC-12. See the
discussion on evaporative cooling under new CFC-11, CFC-12, CFC-113,
CFC-114, and R-500 centrifugal chillers.
(e) Desiccant cooling. Desiccant cooling is acceptable as an
alternative technology to reciprocating chillers using CFC-12. See the
discussion on desiccant cooling under new CFC-11, CFC-12, CFC-113, CFC-
114, and R-500 centrifugal chillers.
(f) Stirling cycle. Stirling Cycle systems are acceptable as an
alternative technology to reciprocating chillers using CFC-12. See the
discussion on the Stirling cycle under new CFC-11, CFC-12, CFC-113,
CFC-114, and R-500 centrifugal chillers.
(9) CFC-11, CFC-12, and R-502 Industrial Process Refrigeration,
Retrofit. Please note that different temperature regimes may affect the
applicability of substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in retrofitted industrial process refrigeration. See the
discussion on HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-114, and
R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-11,
CFC-12, and R-502 in retrofitted industrial process refrigeration. See
the discussion on HFC-134a under retrofitted CFC-12 centrifugal
chillers.
(c) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-11, CFC-
12, and R-502 in retrofitted industrial process refrigeration. Two of
the constituents in these blends are HCFCs and contribute to ozone
depletion, and production of these compounds will be phased out
according to the accelerated schedule. While the GWP of HCFC-22 is
somewhat high, refrigerant leak regulations should reduce its
contribution to global warming. The GWPs of the other components are
low. Although these blends do contain one flammable constituent, HFC-
152a, the blends themselves are not flammable. In addition, each blend
is a near azeotrope, and it does not fractionate in normal operation.
Finally, leak testing of each blend demonstrated that while the vapor
and liquid compositions changed, neither phase became flammable.
Testing of these blends with centrifugal compressors is inadequate, and
therefore such use is not recommended by the manufacturer. Further
testing may resolve this uncertainty.
(d) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-11, CFC-12,
and R-502 in retrofitted industrial process refrigeration. HCFC-22
contributes to ozone depletion, and will be phased out according to the
accelerated schedule. Although these blends contain one flammable
constituent, propane, the blends themselves are not flammable. In
addition, the blends are near azeotropes, meaning they do not change
composition between the vapor and the liquid phase. Therefore, it is
unlikely that the blends would fractionate during normal operation,
resulting in an enrichment of the flammable component. Finally, while
testing demonstrated that the vapor and liquid compositions changed
during leaks, neither phase became flammable. Testing of these blends
with centrifugal compressors is inadequate, and therefore such use is
not recommended by the manufacturer. Further testing may resolve this
uncertainty.
(e) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-11, CFC-12, and R-502 in retrofitted
industrial process refrigeration. None of this blend's constituents
contains chlorine, and thus this blend poses no threat to stratospheric
ozone. However, HFC-125 and HFC-143a have very high GWPs. EPA strongly
encourages recycling and reclamation of this blend in order to reduce
its direct global warming impact. Although HFC-143a is flammable, the
blend is not. It is an azeotrope, so it will not fractionate during
operation. Leak testing has demonstrated that its composition never
becomes flammable.
(f) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-11, CFC-12, and R-502 in
retrofitted industrial process refrigeration. None of this blend's
constituents contains chlorine, and thus this blend poses no threat to
stratospheric ozone. However, HFC-125 and HFC-143a have very high GWPs,
and the GWP of HFC-134a is somewhat high. EPA strongly encourages
recycling and reclamation of this blend in order to reduce its direct
global warming impact. Although HFC-143a is flammable, the blend is
not. It is a near azeotrope, so it will not fractionate during
operation. Leak testing has demonstrated that its composition never
becomes flammable.
(g) Ammonia. Ammonia is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in retrofitted industrial process refrigeration. See the
discussion on ammonia under new CFC-11, CFC-12, CFC-113, CFC-114, and
R-500 centrifugal chillers.
(h) Propane. Propane is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in retrofitted industrial process refrigeration
equipment. Propane does not contribute to ozone depletion and it
exhibits a negligible GWP. Propane is flammable, and as such EPA
recommends but does not require that it only be used at industrial
facilities which manufacture or use hydrocarbons in the process stream.
Such facilities are designed to comply with the safety standards
required for managing flammable chemicals.
(i) Propylene. Propylene is acceptable as a substitute for CFC-11,
CFC-12, and R-502 in retrofitted industrial process refrigeration.
Propylene does not contribute to ozone depletion, nor does it
contribute significantly to global warming. Propylene is a flammable
refrigerant and as such, EPA recommends but does not require that it
only be used at industrial facilities which already manufacture or use
hydrocarbons in the process stream. Such facilities are designed to
comply with the safety standards required for managing flammable
chemicals.
(j) Butane. Butane is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in retrofitted industrial process refrigeration. Butane
does not contribute to ozone depletion, nor does it contribute
significantly to global warming. Butane is a flammable refrigerant and
as such, EPA recommends but does not require that it only be used at
industrial facilities which already manufacture or use hydrocarbons in
the process stream. Such facilities are designed to comply with the
safety standards required for managing flammable chemicals.
(k) Hydrocarbon Blend A. Hydrocarbon Blend A is acceptable as a
substitute for CFC-11, CFC-12, and R-502 in retrofitted industrial
process refrigeration equipment. This blend does not contribute to
ozone depletion, nor does it contribute significantly to global
warming. This blend contains flammable refrigerants and as such, EPA
recommends but does not require that it only be used at industrial
facilities which already manufacture or use hydrocarbons in the process
stream. Such facilities are designed to comply with the safety
standards required for managing flammable chemicals.
(l) Chlorine. Chlorine is acceptable as a substitute for CFC-11,
CFC-12, and R-502 in retrofitted industrial process refrigeration
equipment. Chlorine is a highly reactive chemical and as such, EPA
recommends but does not require that chlorine only be used at
industrial facilities which manufacture or use chlorine in the process
stream. Note, however, that OSHA's Process Safety Management Standards
apply to the use of chlorine.
(10) CFC-11, CFC-12, and R-502 Industrial Process Refrigeration,
New. Please note that different temperature regimes may affect the
applicability of substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in new industrial process refrigeration. See the
discussion on HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-114, and
R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-11,
CFC-12, and R-502 in new industrial process refrigeration. See the
discussion on HFC-134a under retrofitted CFC-12 centrifugal chillers.
(c) HFC-227ea. HFC-227ea is acceptable as a substitute for CFC-12
in new industrial process refrigeration. See the discussion on HFC-
227ea under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(d) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-11, CFC-12,
and R-502 in new industrial process refrigeration. See the discussion
on these blends under retrofitted CFC-11, CFC-12, and R-502 industrial
process refrigeration.
(e) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-11, CFC-12, and R-502 in new
industrial process refrigeration. See the discussion on this blend
under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(f) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-11, CFC-12, and R-502 in
new industrial process refrigeration. See the discussion on this blend
under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(g) Ammonia. Ammonia is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in new industrial process refrigeration. See the
discussion on ammonia under new CFC-11, CFC-12, CFC-113, CFC-114, and
R-500 centrifugal chillers.
(h) Propane. Propane is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in new industrial process refrigeration equipment. See
the discussion on propane under retrofitted CFC-11, CFC-12, and R-502
industrial process refrigeration.
(i) Propylene. Propylene is acceptable as a substitute for CFC-11,
CFC-12, and R-502 in new industrial process refrigeration. See the
discussion on propylene under retrofitted CFC-11, CFC-12, and R-502
industrial process refrigeration.
(j) Butane. Butane is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in new industrial process refrigeration. See the
discussion on butane under retrofitted CFC-11, CFC-12, and R-502
industrial process refrigeration.
(k) Hydrocarbon Blend A. Hydrocarbon Blend A is acceptable as a
substitute for CFC-11, CFC-12, and R-502 in new industrial process
refrigeration equipment. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(l) Chlorine. Chlorine is acceptable as a substitute for CFC-11,
CFC-12, and R-502 in new industrial process refrigeration equipment.
See the discussion on chlorine under retrofitted CFC-11, CFC-12, and R-
502 industrial process refrigeration.
(m) Evaporative cooling. Evaporative cooling is acceptable as an
alternative technology to industrial process refrigeration using CFC-
11, CFC-12, or R-502. See the discussion on evaporative cooling under
new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(n) Desiccant cooling. Desiccant cooling is acceptable as an
alternative technology to industrial process refrigeration using CFC-
11, CFC-12, or R-502. See the discussion on desiccant cooling under new
CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(o) Nitrogen direct gas expansion. Nitrogen direct gas expansion is
acceptable as an alternative technology to industrial process
refrigeration using CFC-12, R-500, or R-502. Nitrogen is expanded
within an enclosed area to absorb heat. The cycle is open; the nitrogen
is released to the atmosphere after absorbing heat from the container.
Nitrogen is a common gas that is nontoxic and nonflammable.
(p) Stirling cycle. Stirling cycle systems are acceptable as an
alternative technology to industrial process refrigeration using CFC-
11, CFC-12, or R-502. See the discussion on the Stirling cycle under
new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(11) R-400(60/40) and CFC-114 Industrial Process Air Conditioning,
Retrofit. (a) HCFC-124. HCFC-124 is acceptable as a substitute for R-
400 (60/40) and CFC-114 in industrial process air conditioning. HCFC-
124 has a very low ODP and GWP. HCFC-124 is the only refrigerant that
has been submitted for this end-use, and EPA invites more submissions
and information related to substitutes.
(12) R-400(60/40) and CFC-114 Industrial Process Air Conditioning,
New. (a) HCFC-124. HCFC-124 is acceptable as a substitute for R-400
(60/40) and CFC-114 in industrial process air conditioning. HCFC-124
has a very low ODP and GWP. It is nonflammable. HCFC-124 is the only
refrigerant that has been submitted for this end-use, and EPA invites
more submissions and information related to substitutes.
(13) CFC-12 and R-502 Ice Skating Rinks, Retrofit. Please note that
different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12 and
R-502 in retrofitted ice skating rinks. See the discussion on HCFC-22
under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 and
R-502 in retrofitted ice skating rinks. See the discussion on HFC-134a
under retrofitted CFC-12 centrifugal chillers.
(c) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted ice skating rinks. See the discussion on these
blends under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(d) Ammonia. Ammonia is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in retrofitted ice skating rinks. See the discussion on
ammonia under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500
centrifugal chillers.
(14) CFC-12 and R-502 Ice Skating Rinks, New. Please note that
different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12 and
R-502 in new ice skating rinks. See the discussion on HCFC-22 under new
CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 and
R-502 in new ice skating rinks. See the discussion on HFC-134a under
retrofitted CFC-12 centrifugal chillers.
(c) Ammonia. Ammonia is acceptable as a substitute for CFC-11, CFC-
12, and R-502 in new ice skating rinks. See the discussion on ammonia
under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(15) CFC-114 Uranium Isotope Separation Processing, Retrofit. (a)
Cycloperfluorobutane (C4F8). Cycloperfluorobutane
(C4F8) is acceptable as a substitute for CFC-114 in uranium
isotope separation processing. C4F8 is a PFC. It has a very
long lifetime and a very high GWP. The Department of Energy (DOE) has
examined several other substitutes and none meets the requirements for
this application. DOE is pursuing a leak reduction program which should
further restrict emissions of this refrigerant.
(b) Perfluoro-n-butane (C4F10). Perfluoro-n-butane
(C4F10) is acceptable as a substitute for CFC-114 in uranium
isotope separation processing. C4F10 is a PFC. It has a very
long lifetime and a very high GWP. The Department of Energy (DOE) has
examined several other substitutes and none meets the requirements for
this application. DOE is pursuing a leak reduction program which should
further restrict emissions of this refrigerant.
(c) Perfluoropentane (C5F12). Perfluoropentane
(C5F12) is acceptable as a substitute for CFC-114 in uranium
isotope separation processing. C5F12 is a PFC. It has a very
long lifetime and a very high GWP. EPA strongly encourages users to
pursue leak reduction strategies and to recover the fluid when the unit
is retired.
(d) Perfluorohexane (C6F14). Perfluorohexane
(C6F14) is acceptable as a substitute for CFC-114 in uranium
isotope separation processing. C6F14 is a PFC. It has a very
long lifetime and a very high GWP. EPA strongly encourages users to
pursue leak reduction strategies and to recover the fluid when the unit
is retired.
(e) Perfluoro-n-methyl morpholine (C5F11NO). Perfluoro-n-
methly morpholine (C5F11NO) is acceptable as a substitute for
CFC-114 in uranium isotope separation processing. C5F11NO is
a PFC. It has a very long lifetime and a very high GWP. EPA strongly
encourages users to pursue leak reduction strategies and to recover the
fluid when the unit is retired.
(16) CFC-12 and R-502 Cold Storage Warehouses, Retrofit. Please
note that different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12 and
R-502 in retrofitted cold storage warehouses. See the discussion on
HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500
centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 and
R-502 in retrofitted cold storage warehouses. See the discussion on
HFC-134a under retrofitted CFC-12 centrifugal chillers.
(c) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted cold storage warehouses. Testing of these blends
with centrifugal compressors is inadequate, and therefore such use is
not recommended by the manufacturer. Further testing may resolve this
uncertainty. For further information, see the discussion on these
blends under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(d) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted cold storage warehouses. Testing of these blends
with centrifugal compressors is inadequate, and therefore such use is
not recommended by the manufacturer. Further testing may resolve this
uncertainty. For further information, see the discussion on these
blends under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(e) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-12 and R-502 in retrofitted cold
storage warehouses. See the discussion on this blend under retrofitted
CFC-11, CFC-12, and R-502 industrial process refrigeration.
(f) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-12 and R-502 in retrofitted
cold storage warehouses. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(17) CFC-12 and R-502 Cold Storage Warehouses, New. Please note
that different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12 and
R-502 in new cold storage warehouses. See the discussion on HCFC-22
under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 and
R-502 in new cold storage warehouses. See the discussion on HFC-134a
under retrofitted CFC-12 centrifugal chillers.
(c) HFC-227ea. HFC-227ea is acceptable as a substitute for CFC-12
in new cold storage warehouses. See the discussion on HFC-227ea under
new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(d) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-12 and R-
502 in new cold storage warehouses. Testing of these blends with
centrifugal compressors is inadequate, and therefore such use is not
recommended by the manufacturer. Further testing may resolve this
uncertainty. For further information, see the discussion on these
blends under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(e) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-12 and R-502 in new cold storage
warehouses. See the discussion on this blend under retrofitted CFC-11,
CFC-12, and R-502 industrial process refrigeration.
(f) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-12 and R-502 in new cold
storage warehouses. See the discussion on this blend under retrofitted
CFC-11, CFC-12, and R-502 industrial process refrigeration.
(g) Ammonia. Ammonia is acceptable as a substitute for CFC-12 and
R-502 in new cold storage warehouses. See the discussion on ammonia
under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(h) Evaporative cooling. Evaporative cooling is acceptable as an
alternative technology to cold storage warehouses using CFC-12 or R-
502. See the discussion on evaporative cooling under new CFC-11, CFC-
12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(i) Desiccant cooling. Desiccant cooling is acceptable as an
alternative technology to cold storage warehouses using CFC-12 or R-
502. See the discussion on desiccant cooling under new CFC-11, CFC-12,
CFC-113, CFC-114, and R-500 centrifugal chillers.
(j) High to low pressure stepdown. High to low pressure stepdown
process is acceptable as an alternative technology to cold storage
warehouses using CFC-12 or R-502. This process takes advantage of the
work potential of pressurized natural gas. As its pressure is reduced
from transmission pipes to the distribution system, the gas cools. This
refrigeration is then used to cool a transfer medium such as water,
which then cools the refrigerated space. It uses very little energy and
produces no global warming emissions, since the gas is not burned.
(k) Stirling cycle. Stirling cycle systems are acceptable as an
alternative technology to cold storage warehouses using CFC-12 or R-
502. See the discussion on the Stirling cycle under new CFC-11, CFC-12,
CFC-113, CFC-114, and R-500 centrifugal chillers.
(18) CFC-12, R-500, and R-502 Refrigerated Transport, Retrofit.
Please note that different temperature regimes may affect the
applicability of substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12, R-
500, and R-502 in retrofitted refrigerated transport. See the
discussion on HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-114, and
R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12, R-
500, and R-502 in retrofitted refrigerated transport. See the
discussion on HFC-134a under retrofitted CFC-12 centrifugal chillers.
(c) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12, R-
500, and R-502 in retrofitted refrigerated transport. See the
discussion on these blends under retrofitted CFC-11, CFC-12, and R-502
industrial process refrigeration.
(d) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-12, R-500,
and R-502 in retrofitted refrigerated transport. See the discussion on
these blends under retrofitted CFC-11, CFC-12, and R-502 industrial
process refrigeration.
(e) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-12, R-500, and R-502 in retrofitted
refrigerated transport. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(f) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-12, R-500, and R-502 in
retrofitted refrigerated transport. See the discussion on this blend
under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(19) CFC-12 and R-502 Refrigerated Transport, New. Please note that
different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12, R-
500, and R-502 in new refrigerated transport. See the discussion on
HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500
centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12, R-
500, and R-502 in new refrigerated transport. See the discussion on
HFC-134a under retrofitted CFC-12 centrifugal chillers.
(c) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-12, R-500,
and R-502 in new refrigerated transport. See the discussion on these
blends under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(d) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-12, R-500, and R-502 in retrofitted
new refrigerated transport. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(e) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-12, R-500, and R-502 in new
refrigerated transport. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(f) Stirling cycle. Stirling cycle systems are acceptable as an
alternative technology to refrigerated transport using CFC-12, R-500,
or R-502. Stirling cycle systems have been in use for many years in
this end-use. For further information, see the discussion on the
Stirling cycle under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500
centrifugal chillers.
(g) Nitrogen direct gas expansion. Nitrogen direct gas expansion is
acceptable as an alternative technology to refrigerated transport using
CFC-12, R-500, or R-502. Nitrogen is expanded within a refrigerated
transport unit to absorb heat. The cycle is open; the nitrogen is
released to the atmosphere after absorbing heat from the container.
Nitrogen is a common gas that is nontoxic and nonflammable. It has been
used successfully for many years in this end-use.
(20) CFC-12 and R-502 Retail Food Refrigeration, Retrofit. Please
note that different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12 and
R-502 in retrofitted retail food refrigeration. See the discussion on
HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500
centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 and
R-502 in retrofitted retail food refrigeration. See the discussion on
HFC-134a under retrofitted CFC-12 centrifugal chillers.
(c) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12, R-
500, and R-502 in retrofitted retail food refrigeration. See the
discussion on these blends under retrofitted CFC-11, CFC-12, and R-502
industrial process refrigeration.
(d) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-12, R-500,
and R-502 in retrofitted retail food refrigeration. See the discussion
on these blends under retrofitted CFC-11, CFC-12, and R-502 industrial
process refrigeration.
(e) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-12, R-500, and R-502 in retrofitted
retail food refrigeration. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(f) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-12, R-500, and R-502 in
retrofitted retail food refrigeration. See the discussion on this blend
under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(21) CFC-12 and R-502 Retail Food Refrigeration, New. Please note
that different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12 and
R-502 in new retail food refrigeration. See the discussion on HCFC-22
under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 and
R-502 in new retail food refrigeration. See the discussion on HFC-134a
under retrofitted CFC-12 centrifugal chillers.
(c) HFC-227ea. HFC-227ea is acceptable as a substitute for CFC-12
in new retail food refrigeration. See the discussion on HFC-227ea under
new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(d) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-12, R-500,
and R-502 in new retail food refrigeration. See the discussion on these
blends under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(e) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-12, R-500, and R-502 in new retail
food refrigeration. See the discussion on this blend under retrofitted
CFC-11, CFC-12, and R-502 industrial process refrigeration.
(f) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-12, R-500, and R-502 in new
retail food refrigeration. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(g) Ammonia. Ammonia is acceptable as a substitute for CFC-12 and
R-502 in new retail food refrigeration. See the discussion on ammonia
under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(h) Stirling Cycle. Stirling cycle systems are acceptable as an
alternative technology to retail food refrigeration using CFC-12 or R-
502. See the discussion on the Stirling cycle under new CFC-11, CFC-12,
CFC-113, CFC-114, and R-500 centrifugal chillers.
(22) CFC-12 and R-502 Commercial Ice Machines, Retrofit. Please
note that different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted commercial ice machines. See the discussion on these
blends under retrofitted CFC-11, CFC-12 and R-502 industrial process
refrigeration.
(b) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted commercial ice machines. See the discussion on these
blends under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(c) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-12, R-500, and R-502 in retrofitted
commercial ice machines. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(d) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-12, R-500, and R-502 in
retrofitted commercial ice machines. See the discussion on this blend
under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(23) CFC-12 and R-502 Commercial Ice Machines, New. Please note
that different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12 and
R-502 in new commercial ice machines. See the discussion on HCFC-22
under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 and
R-502 in new commercial ice machines. See the discussion on HFC-134a
under retrofitted CFC-12 centrifugal chillers.
(c) R-402A and R-402B. R-402A and R-402B, which consist of HCFC-22,
propane, and HFC-125, are acceptable as substitutes for CFC-12 and R-
502 in new commercial ice machines. See the discussion on these blends
under retrofitted CFC-11, CFC-12, and R-502 industrial process
refrigeration.
(d) R-404A. R-404A, which consists of HFC-125 and HFC-143a, is
acceptable as a substitute for CFC-12, R-500, and R-502 in new
commercial ice machines. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(e) R-507. R-507, which consists of HFC-125, HFC-143a, and HFC-
134a, is acceptable as a substitute for CFC-12, R-500, and R-502 in new
commercial ice machines. See the discussion on this blend under
retrofitted CFC-11, CFC-12, and R-502 industrial process refrigeration.
(f) Ammonia. Ammonia is acceptable as a substitute for CFC-12 and
R-502 in new commercial ice machines. See the discussion on ammonia
under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(g) Stirling cycle. Stirling cycle systems are acceptable as an
alternative technology to commercial ice machines using CFC-12 or R-
502. See the discussion on the Stirling cycle under new CFC-11, CFC-12,
CFC-113, CFC-114, and R-500 centrifugal chillers.
(24) CFC-12 Vending Machines, Retrofit. (a) HCFC-22. HCFC-22 is
acceptable as a substitute for CFC-12 in retrofitted vending machines.
See the discussion on HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-
114, and R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 in
retrofitted vending machines. See the discussion on HFC-134a under
retrofitted CFC-12 centrifugal chillers.
(c) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted vending machines. See the discussion on these blends
under retrofitted CFC-11, CFC-12 and R-502 industrial process
refrigeration.
(25) CFC-12 Vending Machines, New. (a) HCFC-22. HCFC-22 is
acceptable as a substitute for CFC-12 in new vending machines. See the
discussion on HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-114, and
R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 in
new vending machines. See the discussion on HFC-134a under retrofitted
CFC-12 centrifugal chillers.
(c) Stirling cycle. Stirling cycle systems are acceptable as an
alternative technology to vending machines using CFC-12. See the
discussion on the Stirling cycle under new CFC-11, CFC-12, CFC-113,
CFC-114, and R-500 centrifugal chillers.
(26) CFC-12 Water Coolers, Retrofit. (a) HFC-134a. HFC-134a is
acceptable as a substitute for CFC-12 in retrofitted water coolers. See
the discussion on HFC-134a under retrofitted CFC-12 centrifugal
chillers.
(b) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted water coolers. See the discussion on these blends
under retrofitted CFC-11, CFC-12 and R-502 industrial process
refrigeration.
(27) CFC-12 Water Coolers, New. (a) HCFC-22. HCFC-22 is acceptable
as a substitute for CFC-12 in new water coolers. See the discussion on
HCFC-22 under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500
centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 in
new water coolers. See the discussion on HFC-134a under retrofitted
CFC-12 centrifugal chillers.
(c) Stirling cycle. Stirling cycle systems are acceptable as an
alternative technology to water coolers using CFC-12. See the
discussion on the Stirling cycle under new CFC-11, CFC-12, CFC-113,
CFC-114, and R-500 centrifugal chillers.
(28) CFC-12 Household Refrigerators, Retrofit. (a) HCFC-22. HCFC-22
is acceptable as a substitute for CFC-12 and R-502 in retrofitted
household refrigerators. See the discussion on HCFC-22 under new CFC-
11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 in
retrofitted household refrigerators. See the discussion on HFC-134a
under retrofitted CFC-12 centrifugal chillers.
(c) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted household refrigerators. See the discussion on these
blends under retrofitted CFC-11, CFC-12 and R-502 industrial process
refrigeration.
(d) HCFC Blend Alpha. HCFC Blend Alpha, which consists of HCFC-22
and HCFC-142b, is acceptable as a substitute for CFC-12 in retrofitted
household refrigerators. This blend's components contribute
significantly less to ozone depletion than CFC-12. However, the two
components have the highest ODPs of all refrigerant alternatives, and
will be phased out under the accelerated phaseout schedule. In
addition, the GWPs of the components are high compared to most of the
other alternatives in this end-use. Although this blend does contain a
flammable constituent, testing has shown that the blend itself is not
flammable and that it must experience significant fractionation before
flammability becomes a risk. Given the small refrigerant charge size
and the hermetic nature of refrigerators, it is unlikely for a leak
resulting in such fractionation to occur.
(29) CFC-12 Household Refrigerators, New. (a) HCFC-22. HCFC-22 is
acceptable as a substitute for CFC-12 and R-502 in new household
refrigerators. See the discussion on HCFC-22 under new CFC-11, CFC-12,
CFC-113, CFC-114, and R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 in
new household refrigerators. See the discussion on HFC-134a under
retrofitted CFC-12 centrifugal chillers.
(c) HFC-152a. HFC-152a is acceptable as a substitute for CFC-12 in
new household refrigerators. HFC-152a does not contribute to ozone
depletion. In addition, HFC-152a's GWP and atmospheric lifetime are
significantly lower than those of most alternatives. Although HFC-152a
is flammable, a risk assessment demonstrated it could be used safely in
this end-use.
(d) HCFC Blend Alpha. HCFC Blend Alpha, which consists of HCFC-22
and HCFC-142b, is acceptable as a substitute for CFC-12 in new
household refrigerators. See the discussion on this blend under
retrofitted CFC-12 household refrigerators.
(e) R200b blend. R200b blend is acceptable as a substitute for CFC-
12 in new household refrigerators. R200b does not contribute to ozone
depletion. In addition, the GWPs and atmospheric lifetimes of the
blend's constituents are less than those of CFC-12. However, the GWP of
one component is high compared to those of other alternatives for this
end-use. One component of R200b is flammable, but a risk assessment has
shown that use of R200b in household refrigerators poses negligible
additional risk of fire, given the hermetic nature of the equipment,
the small charge, and the low probability of ignition.
(f) Stirling cycle. Stirling cycle systems are acceptable as an
alternative technology to household refrigerators using CFC-12.
Research and development efforts are underway to produce household
refrigerators using this cycle. Further information is discussed under
new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(30) CFC-12 and R-502 Household Freezers, Retrofit. (a) HCFC-22.
HCFC-22 is acceptable as a substitute for CFC-12 and R-502 in
retrofitted household freezers. See the discussion on HCFC-22 under new
CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 and
R-502 in retrofitted household freezers. See the discussion on HFC-134a
under retrofitted CFC-12 centrifugal chillers.
(c) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted household freezers. See the discussion on these
blends under retrofitted CFC-11, CFC-12 and R-502 industrial process
refrigeration.
(31) CFC-12 and R-502 Household Freezers, New. (a) HCFC-22. HCFC-22
is acceptable as a substitute for CFC-12 and R-502 in new household
freezers. See the discussion on HCFC-22 under new CFC-11, CFC-12, CFC-
113, CFC-114, and R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 and
R-502 in new household freezers. See the discussion on HFC-134a under
retrofitted CFC-12 centrifugal chillers.
(c) HFC-152a. HFC-152a is acceptable as a substitute for CFC-12 and
R-502 in new household refrigerators. HFC-152a does not contribute to
ozone depletion. In addition, HFC-152a's GWP and atmospheric lifetime
are significantly lower than those of most alternatives. Although HFC-
152a is flammable, a risk assessment demonstrated it could be used
safely in this end-use.
(d) Stirling cycle. Stirling cycle systems are acceptable as an
alternative technology to household freezers using CFC-12 or R-502. See
the discussion on the Stirling cycle under new CFC-11, CFC-12, CFC-113,
CFC-114, and R-500 centrifugal chillers.
(32) CFC-12 and R-500 Residential Dehumidifiers, Retrofit. Please
note that different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12 in
retrofitted residential dehumidifiers. See the discussion on HCFC-22
under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal
chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 in
retrofitted residential dehumidifiers. See the discussion on HFC-134a
under retrofitted CFC-12 centrifugal chillers.
(c) R-401A and R-401B. R-401A and R-401B, which consist of HCFC-22,
HFC-152a, and HCFC-124, are acceptable as substitutes for CFC-12 and R-
502 in retrofitted residential dehumidifiers. See the discussion on
these blends under retrofitted CFC-11, CFC-12 and R-502 industrial
process refrigeration.
(33) CFC-12 and R-500 Residential Dehumidifiers, New. Please note
that different temperature regimes may affect the applicability of
substitutes within this end-use.
(a) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-12 in
new residential dehumidifiers. See the discussion on HCFC-22 under new
CFC-11, CFC-12, CFC-113, CFC-114, and R-500 centrifugal chillers.
(b) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 in
new residential dehumidifiers. See the discussion on HFC-134a under
retrofitted CFC-12 centrifugal chillers.
(34) CFC-12 Motor Vehicle Air Conditioners, Retrofit. (a) HFC-134a.
HFC-134a is acceptable as a substitute for CFC-12 in retrofitted motor
vehicle air conditioners. HFC-134a does not contribute to ozone
depletion. HFC-134a's GWP and atmospheric lifetime are close to those
of other alternatives which have been determined to be acceptable for
this end-use. However, HFC-134a's contribution to global warming could
be significant in leaky end-uses such as MVACS. EPA has determined that
the use of HFC-134a in these applications is acceptable because
industry continues to develop technology to limit emissions. In
addition, the number of available substitutes for use in MVACS is
currently limited. HFC-134a is not flammable and its toxicity is low.
While HFC-134a is compatible with most existing refrigeration and air
conditioning equipment parts, it is not compatible with the mineral
oils currently used in such systems. An ester-based lubricant should be
used rather than mineral oils.
(b) R-401C. R-401C, which consists of HCFC-22, HFC-152a, and HCFC-
124, is acceptable as a substitute for CFC-12 in retrofitted motor
vehicle air conditioners. HCFC-22 and HCFC-124 contribute to ozone
depletion. The production of HCFC-22 will be phased out according to
the accelerated phaseout schedule. The GWP of HCFC-22 is somewhat
higher than other alternatives for this end-use. Experimental data
indicate that HCFC-22 may leak through flexible hosing in mobile air
conditioners at a high rate. In order to preserve the blend's
composition and to reduce its contribution to global warming, EPA
strongly recommends using barrier hoses when hose assemblies need to be
replaced during a retrofit procedure. The GWPs of the other components
are low. Although this blend does contain one flammable constituent,
the blend itself is not flammable. In addition, this blend is a near
azeotrope, meaning it does not change composition during evaporation
and compression. Finally, although testing demonstrated that the vapor
and liquid compositions changed during leaks, neither phase became
flammable.
(35) CFC-12 Motor Vehicle Air Conditioners, New. (a) HFC-134a. HFC-
134a is acceptable as a substitute for CFC-12 in new motor vehicle air
conditioners. HFC-134a does not contribute to ozone depletion. HFC-
134a's GWP and atmospheric lifetime are close to those of other
alternatives which have been determined to be acceptable for this end-
use. However, HFC-134a's contribution to global warming could be
significant in leaky end-uses such as MVACS. EPA has determined that
the use of HFC-134a in these applications is acceptable because
industry continues to develop technology to limit emissions. In
addition, the number of available substitutes for use in MVACS is
currently limited. HFC-134a is not flammable and its toxicity is low.
While HFC-134a is compatible with most existing refrigeration and air
conditioning equipment parts, it is not compatible with the mineral
oils currently used in such systems. An ester-based lubricant should be
used rather than mineral oils.
(b) R-401C. R-401C, which consists of HCFC-22, HFC-152a, and HCFC-
124, is acceptable as a substitute for CFC-12 in new motor vehicle air
conditioners. HCFC-22 and HCFC-124 contribute to ozone depletion. The
production of HCFC-22 will be phased out according to the accelerated
phaseout schedule. The GWP of HCFC-22 is somewhat higher than other
alternatives for this end-use. Experimental data indicate that HCFC-22
may leak through flexible hosing in mobile air conditioners at a high
rate. In order to preserve the blend's composition and to reduce its
contribution to global warming, EPA strongly recommends using barrier
hoses when hose assemblies need to be replaced during a retrofit
procedure. The GWPs of the other components are low. Although this
blend does contain one flammable constituent, the blend itself is not
flammable. In addition, this blend is a near azeotrope, meaning it does
not change composition during evaporation and compression. Finally,
although testing demonstrated that the vapor and liquid compositions
changed during leaks, neither phase became flammable.
(c) Evaporative cooling. Evaporative cooling is acceptable as an
alternative technology to motor vehicle air conditioners using CFC-12.
Evaporative cooling does not contribute to ozone depletion or global
warming and has the potential to be more energy efficient than current
refrigeration and air conditioning systems. Evaporative cooling uses no
chemicals, but relies instead on water evaporation as a means of
cooling. It is in widespread use in transit buses in the western U.S.
Recent design improvements have greatly expanded its applicability to
other regions.
(d) CO2 cooling. CO2 cooling systems are acceptable as an
alternative technology to motor vehicle air conditioners using CFC-12.
CO2 systems for motor vehicle air conditioning are currently under
development. EPA believes that with continued development, such systems
could be available within 5 years, and thus they are potentially
available substitutes. CO2 was historically used in refrigeration
systems. It is a well-known, nontoxic, nonflammable gas. Its GWP is
defined as 1, and all other GWPs are indexed to it. Since it is readily
available as a waste gas, no additional chemical will need to be
produced. Thus, the use of CO2 as a refrigerant will not
contribute to global warming.
(e) Stirling cycle. Stirling cycle systems are acceptable as an
alternative technology to motor vehicle air conditioners using CFC-12.
A full scale Stirling cycle motor vehicle air conditioning system has
been built. Further development is necessary to facilitate practical
implementation. For further information see the discussion on the
Stirling cycle under new CFC-11, CFC-12, CFC-113, CFC-114, and R-500
centrifugal chillers.
(36) Heat transfer. Although EPA did not originally intend to
review this end-use, the Agency reconsidered after reexamining the
potential size of annual sales of substitutes. Thus, EPA is currently
reviewing submissions for the use of PFCs in heat transfer systems. EPA
anticipates including its final determination in the first SNAP update.
b. Unacceptable substitutes. (1) HCFC-22/HCFC-142b/CFC-12 blend. A
HCFC-22/HCFC-142b/CFC-12 blend is unacceptable as a substitute for CFC-
12 in:
Commercial comfort air conditioning;
Industrial process refrigeration systems;
Ice skating rinks;
Cold storage warehouses;
Refrigerated transport;
Retail food refrigeration;
Vending machines;
Water coolers;
Commercial ice machines;
Household refrigerators;
Household freezers;
Residential dehumidifiers; and
Motor vehicle air conditioning.
It is also unacceptable as a substitute for HCFC-22 in residential and
packaged HCFC-22 air conditioning. Other substitutes for CFC-12 exist
which contain no class I substances. In addition, because this blend
contains CFC-12 (which has an ODP 20 times that of HCFC-22), it poses a
greater risk to stratospheric ozone than the use of HCFC-22 alone.
(2) HCFC-141b. HCFC-141b is unacceptable as a substitute for CFC-11
in new centrifugal chillers. This substance has a high ozone depletion
potential. At least one other substitute exists that presents lower
overall risk.
(3) Hydrocarbon Blend A. Hydrocarbon Blend A is unacceptable as a
substitute for CFC-12 in:
Commercial comfort air conditioning;
Ice skating rinks;
Cold storage warehouses;
Refrigerated transport;
Retail food refrigeration;
Vending machines;
Water coolers;
Commercial ice machines;
Household refrigerators;
Household freezers;
Residential dehumidifiers; and
Motor vehicle air conditioning.
Flammability is the primary concern. EPA believes the use of this
substitute in very leaky uses like motor vehicle air conditioning may
pose a high risk of fire. EPA requires a risk assessment be conducted
to demonstrate this blend may be safely used in any CFC-12 end-uses.
E. Foams
1. Overview
Foam plastics accounted for approximately 18 percent of all U.S.
consumption of ozone-depleting chemicals on an ODP-weighted basis in
1990. Five class I chemicals--CFC-11, CFC-12, CFC-113, CFC-114, and
methyl chloroform--are used as blowing agents in foam production. These
five compounds are used in a wide variety of applications.
Foam plastics manufactured with CFCs fall into four major
categories: polyurethane, phenolic, extruded polystyrene, and
polyolefin. Historically, CFC-11 and CFC-113, which remain in a liquid
state at room temperature, have been used as blowing agents in
polyurethane and phenolic foams. CFC-12 and CFC-114, which have lower
boiling points than CFC-11 and CFC-113 and are gases at room
temperature, are used in polyolefin and polystyrene foams. In addition
to CFCs, methyl chloroform is used as a blowing agent in some flexible
polyurethane foams.
Due to the wide variety of applications that foams represent, the
Agency has divided its analysis of foam plastics into the following ten
distinct end-use sectors:
Rigid polyurethane and polyisocyanurate laminated
boardstock;
Rigid polyurethane appliance;
Rigid polyurethane spray and commercial refrigeration, and
sandwich panels;
Rigid polyurethane slabstock and other foams;
Polystyrene extruded insulation boardstock and billet;
Phenolic insulation board;
Flexible polyurethane;
Polyurethane integral skin;
Polystyrene extruded sheet; and
Polyolefin.
The SNAP determinations in this final rule distinguish between these
ten end-use sectors because the mix of potential alternatives to Class
I blowing agents, and potential emission and exposure profiles, differ
for each. Appendix B at the end of this preamble lists in tabular form
the Agency's determinations on substitutes in the foam sector. These
determinations are based on the risk screens described in the
background document entitled, ``Risk Screen on the Use of Substitutes
for Class I Ozone-Depleting Substances: Foam-Blowing Agents'' and
discussed in supporting memoranda. The table also includes as
``pending'' substitutes for which the Agency has not yet issued
determinations. Vendors or users of substitutes not described in
Appendix B should submit information on these uses, so that the Agency
can review them and issue a SNAP determination.
2. Alternative Blowing Agents
Under the SNAP program, the evaluation of alternatives for CFCs
depends on a number of factors. These include toxicity, flammability,
environmental concerns, and, in the case of insulating foams, the
insulating efficiency of alternatives.
Toxicity concerns associated with the use of alternative chemicals
relate to the exposure of workers and consumers to the chemicals or to
the decomposition products these chemicals may form slowly over time in
foam products. The likely degree of human health risk associated with
an alternative depends not only on the nature of a substitute chemical
but also on the chemical composition, manufacturing process, and
product applications that characterize the foam end-use sector into
which that substitute will be introduced.
Flammability concerns, like toxicity concerns, have to do with
possible danger to workers and consumers. Such danger includes possible
ignition of materials during manufacturing, storage, or transportation,
and the fire hazard posed by the final product. Alternatives to CFCs
have varying degrees of flammability. As in the case of toxicity,
however, the composition, production processes, and end-use
applications that characterize each foam type dictate the potential
risks associated with flammability.
In addition to posing toxicity and flammability risks, alternatives
may have deleterious effects on the environment. Such effects may
include stratospheric ozone depletion, global warming, and contribution
to smog or tropospheric ozone formation. HCFCs have, in varying
degrees, the potential to deplete ozone; both HCFCs and HFCs have
global warming potential; and various potential alternatives,
especially hydrocarbons, are volatile organic compounds (VOCs) that
contribute to the formation of ozone, or smog, in the lower atmosphere.
The use of alternative blowing agents can have an adverse affect on
the insulating capacity of foam products due to higher thermal
conductivity of the substitute. The overall risk screen for substitutes
under SNAP takes into account indirect contributions to global warming.
a. Hydrochlorofluorocarbons. Because of their relatively low
thermal conductivity, hydrochlorofluorocarbons (HCFCs) are considered
necessary transitional alternatives to CFC blowing agents in thermal
insulating foams. Two HCFCs, HCFC-123 and HCFC-141b, can serve as
replacements for CFC-11 in many end-use applications. Because of
limited availability of HCFC-123, HCFC141b represents the more likely
short-term possibility for replacing CFC-11 in several of the
insulating foam sectors. As a result, the Agency has determined that
HCFC-141b, despite its relatively high ODP of 0.11, is an acceptable
transitional alternative to CFC-11 for several foam end-uses. Other
HCFC alternatives are HCFC-22 and HCFC-142b. Although these compounds
are commercially available and have lower ODPs than HCFC-141b, each has
a boiling point significantly lower than CFC-11. As a result,
conversion to HCFC-22 or HCFC-142b from CFC-11 generally entails
significant investment in technical and process modification. HCFC-22
and HCFC-142b do, however, present viable, near-term alternatives to
CFC-12 in extruded polystyrene boardstock and billet foams.
Production of HCFCs is controlled by the Clean Air Act and under
section 605 is scheduled for phase-out by 2030. However, due to new
data concerning greater risks of ozone depletion, EPA promulgated an
accelerated phase-out schedule (58 FR 65018, 12/10/93). Given the
technical and safety concerns associated with many non-HCFC
alternatives, however, disallowing the interim use of HCFCs in
insulating foam end-uses, including the use of HCFC-141b and HCFC-22,
would have adverse effects on human health and the environment.
Effective January 1, 1994, plastic foam products which contain or
are manufactured with HCFCs are banned from sale or distribution into
interstate commerce under section 610 of the CAA. Under section 610,
thermal insulation foam products are, however, exempted from this ban.
Foam insulation product means a product containing or consisting of the
following types of foam: (1) Closed cell rigid polyurethane and
polyisocyanurate foam; (2) closed cell rigid polystyrene boardstock
foam; (3) closed cell rigid phenolic foam; and (4) closed cell rigid
polyethylene foam when such foam is suitable in shape, thickness and
design to be used as a product that provides thermal insulation around
pipes used in heating, plumbing, refrigeration, or industrial process
systems. Any use of acceptable HCFC substitutes listed under SNAP must
comply with restrictions under the section 610 Non-Essential Ban.
b. Hydrofluorocarbons. Hydrofluorocarbons (HFCs) represent a zero-
ODP alternative to CFC blowing agents in many sectors. From the
standpoint of stratospheric ozone depletion alone, HFCs are preferable
to HCFCs as alternative blowing agents. The relatively higher thermal
conductivity of HFCs, however, is likely to hamper the insulating
capabilities of HFC-blown foams unless significant changes in the foam
formulation or process modifications are adopted.
The HFCs hold more promise as near- or intermediate-term
alternatives for CFC-12 in extruded polystyrene foams, particularly in
extruded polystyrene sheet foams. However, issues such as flammability,
global warming potential, cost, and the solubility of HFCs in
polystyrene polymer remain of concern for the industry.
Conversion to HFC-152a may entail significant capital investment in
order to ensure worker safety against fire hazards. Moreover, in the
case of insulating foams, manufacturers will need to guarantee that
foams blown with HFC-152a meet the building code requirements that
apply to the flammability of building materials.
c. Saturated light hydrocarbons C3-C6. Saturated light hydrocarbons
C3-C6, most of which are readily available as bulk chemicals, have the
advantage of being low cost. These chemicals are also halogen free,
thus they are both zero-ODP and zero-GWP. Saturated light hydrocarbons
C3-C6 are currently being used in extruded polystyrene, polyurethane,
and polyolefin non-insulating foam end-uses.
Hydrocarbons have significantly higher thermal conductivities than
do any of the CFCs. Conversion to hydrocarbons could thus lead to the
production of foams with lower insulating efficiency and, possibly, to
a reduction in the energy efficiency of insulated items. Formulation
changes and process modifications have been introduced to increase the
thermal insulating efficiency of hydrocarbon-blown foams. Cyclopentane
is a leading alternative blowing-agent candidate for insulating foams
because of its high boiling point and other physical properties similar
to CFC-11.
Conversion to hydrocarbons may entail significant capital
investment in order to ensure worker safety against fire hazards.
Moreover, in the case of insulating foams, manufacturers will need to
guarantee that foams blown with hydrocarbons meet the building code
requirements that apply to the flammability of building materials.
Hydrocarbons are VOCs and may contribute to the formation of
ground-level ozone, or smog, in the lower atmosphere. Any use of
hydrocarbon blowing agents is subject to the federal, state and local
restrictions that apply to VOCs, and conversion to hydrocarbons could
therefore involve further capital investment to comply with these
restrictions.
d. Other blowing agents. Two other blowing agents, methylene
chloride and acetone, have been identified as substitutes for CFC-11 in
flexible polyurethane foams. Methylene chloride, which already serves
as an auxiliary blowing agent for most grades of flexible polyurethane
foam, is commercially available, and is relatively low cost. Because of
its toxicity, it poses a potential risk to workers and residents in
nearby communities. However, the Agency's analysis of use of this
chemical as a blowing agent indicates risks can be controlled by
adhering to existing regulatory standards. Methylene chloride use is
further restricted in several states and localities, and is listed as a
hazardous waste under RCRA and, thus, users must comply with applicable
RCRA waste disposal requirements. The Agency is also in the process of
addressing residual risks to the general population through emissions
to air under title III section 112 of the CAA. The Agency expects to
issue maximum achievable control technology (MACT) rules governing
methylene chloride use in the foams sector by 1997. Methylene chloride
is not a VOC, and thus, does not contribute to the formation of
tropospheric ozone.
When used as a blowing agent, acetone is capable of yielding all
grades of flexible polyurethane foam. It can serve as an alternative
blowing agent where methylene chloride use is infeasible. Acetone is a
VOC, and must be controlled as such. In addition, plant modifications
may be necessary to accommodate acetone's flammability.
Carbon dioxide (CO2) is an acceptable substitute for all foam
end-uses. Any CO2 blend is acceptable as long as the other
constituents of the blend are acceptable under SNAP. CO2 does
contribute to global warming. In addition, CO2 has the highest
thermal conductivity of the SNAP-listed chemical alternatives, and will
lower the thermal capacity of insulating foams unless significant foam
formulation or process modifications are adopted.
e. Alternative manufacturing processes. The AB Technology is a
commercially available and technically feasible process for replacing
CFCs or other auxiliary blowing agents for most conventional flexible
foam grades. AB Technology employs formic acid in conjunction with
water as the blowing agent for producing flexible polyurethane foam.
The process is based on using the reaction of formic acid with an
isocyanate to produce carbon monoxide in addition to the water/
isocyanate reaction normally used to generate carbon dioxide gas for
the expansion of foam. OSHA has set a permissible exposure level (PEL)
for carbon monoxide of 35 ppm of a time weighted average with a ceiling
not to exceed 200 ppm.
3. Comment Response
The majority of public comments received on the foams sector in the
proposed rule focused on three issues: The viability or availability of
substitutes; the need for listing of alternative technologies or
manufacturing processes, and the need for notification under SNAP for
use of blends or mixture of blowing agents.
a. Viability or availability of listed substitutes. Several
commenters suggested that the NPRM did not sufficiently address the
performance and practicality of use of acceptable substitutes.
Commenters were especially concerned about alternative blowing agents
used in thermal insulation applications, and whether acceptable
substitutes represented existing or experimental use. For example,
several commenters stated that if the alternative blowing agent will
affect the insulating capacity of a foam it should be part of the SNAP
analysis, and the outcome should be discussed as part of the listing
decision. Another commenter contended that for many of the end-uses,
not all of the listed HCFC substitutes are technically viable, but each
should be listed anyway to maximize the breadth of options. This
commenter also reported that uses of some of the HFCs and hydrocarbons
are still in development and, therefore do not represent actual
alternatives.
EPA recognizes that the use of alternative blowing agents in
insulation products can affect the energy efficiency of the final
product. In this final rule, the overall risk characterization for
substitutes under SNAP specifically takes into account indirect
contributions to global warming. However, EPA also recognizes that the
changes in foam formulation or product thickness can result in products
with insulation efficiency equivalent to CFC-blown foam. Therefore, EPA
believes it is appropriate to consider and comment on the difference in
thermal conductivity of alternative blowing agents as compared to the
CFC being replaced, and compared to other acceptable substitutes.
However, it would be inappropriate to comment on the expected
performance of a foam product using one blowing agent versus another,
given that formulations are highly proprietary and can vary
significantly from manufacturer-to-manufacturer. Further, EPA believes
it is preferable to identify a broad range of alternatives, and let the
market determine which alternative produce the best performing
insulation products.
Several commenters requested clarification on the definition of
hydrocarbons. One commenter suggested a more specific definition for
hydrocarbons of ``saturated light hydrocarbons, C3-C6.''
The Agency agrees with these commenters. Since the broad use of
hydrocarbon in the NPRM may be viewed as potentially precluding other
viable substitutes, and because the alternate definition suggested by
the commenter encompasses those specifically listed hydrocarbons as
well as more recently identified materials being tested in foams such
as cyclopentane, this definition has been adopted by EPA in the final
rule.
b. Alternative technologies or manufacturing processes. Several
commenters argued that EPA should not issue its seal of approval for
substitutes that are alternative products, unless and until the Agency
evaluates them with the same degree of detail that HCFCs were
evaluated, particularly with regard to toxicity, technical feasibility,
flammability, and energy impacts.
The Agency believes that alternative products and alternative
manufacturing processes will play an important role in the transition
from ODSs in many sectors. In light of public comment, the Agency
recognized that the SNAP data requirements and the SNAP evaluation
process proposed in the NPRM were biased toward chemical substitutes.
The Agency also agrees with public comment that review of non-chemical
alternatives must be supported by appropriate analysis. In this final
rule, the Agency has made revisions to the SNAP Information Notice to
better account for the different information requirements associated
with non-chemical alternatives and increased the discussion of the
Agency's analysis of non-chemical alternatives in the background
documents.
c. Use of blends. Several commenters argued that EPA's proposed
requirement for notification and review of chemical alternative blends
was unnecessary and burdensome for the foams sector. The comments
proposed that any combination or blend of individually acceptable
blowing agents should be permitted without additional notification to
SNAP. One commenter suggested EPA clarify that the term ``blend'' when
used in the SNAP rule does not refer to individual, separately-
``acceptable'' substitutes, two or more of which may be used in the
same manufacturing process.
In light of these public comments, the Agency re-examined the
analytical basis for reviewing blends, to determine whether the
potential human health and environmental risks would be different for
blends or mixtures of chemicals than those of individual chemicals that
were determined to be acceptable for use in the foams manufacturing
process under SNAP. In particular, the Agency was concerned with
potential synergistic effects of the chemical blends, and that the
decomposition product profile would differ from that of a single
chemical.
The Agency has determined that because of the potential for
formation and emission of decomposition products in rigid closed cell
foams, notification and review under SNAP is required for blends of
chemical alternatives in foam end-uses that encompass residential
products where chronic consumer exposure could occur. These end-uses
are: Polyurethane rigid laminated boardstock, polystyrene extruded
boardstock and billet foams, phenolic foams, and polyolefin foams. This
analysis is detailed in the SNAP technical background document, ``Risk
Screen on the Use of Substitutes for Class I Ozone-Depleting
Substances: Foam Blowing Agents.'' In contrast, for open-celled foams
where the blowing agent is fully emitted from the foams within hours or
days of manufacture, the formation of decomposition products is not a
factor in decisionmaking. For this final rule, use of blends or
mixtures of substitutes listed as acceptable under the SNAP program in
open-celled or closed-cell or semi-rigid end-uses not designated above
does not require notification.
4. Listing Decisions
a. Acceptable substitutes. (1) Rigid polyurethane and
polyisocyanurate laminated boardstock. (a) HCFC-123. HCFC-123 is
acceptable as an alternative blowing agent to CFC-11 in rigid
polyurethane and polyisocyanurate laminated boardstock foam. From the
standpoint of technical feasibility, HCFC-123 represents a viable
alternative to CFC-11 as a potential blowing agent. More specifically,
the physical properties, thermal conductivity, and aging of foams blown
with HCFC-123 are similar to those blown with CFC-11. As a result,
HCFC-123, which has an ozone depleting potential significantly lower
than that of CFC-11, has the potential to replace CFC-11 in many
applications. Nonetheless, availability of HCFC-123 is limited at
present. The acceptable exposure limit (AEL) for HCFC-123 is 30 ppm.
(b) HCFC-141b. HCFC-141b is acceptable as an alternative to CFC-11
in rigid polyurethane and polyisocyanurate laminated boardstock foam.
Although its ODP of 0.11 is relatively high, HCFC-141b offers almost
immediate transition out of CFC uses in this sector. Not only does
HCFC-141b offer a technically feasible alternative to CFC-11, but it is
currently available in quantities sufficient to meet industrial demand.
HCFC-141b is scheduled for phase-out from production on January 1, 2003
under the accelerated phase out rule (58 FR 65018) under section 606 of
the CAA.
(c) HCFC-22. HCFC-22 is acceptable as a substitute for CFC-11 in
rigid polyurethane and polyisocyanurate laminated boardstock foam.
HCFC-22 offers an alternative with significantly less potential to
deplete ozone than CFC-11. Plant or process modifications may be
required to allow use of blowing agents like HCFC-142b that have
significantly lower boiling points than CFC-11. HCFC-22 is subject to
the accelerated phase out rule (58 FR 65018) under section 606 of the
CAA.
(d) HCFC-142b. HCFC-142b is acceptable as a substitute for CFC-11
in rigid polyurethane and polyisocyanurate laminated boardstock foam.
HCFC-142b offers an alternative with significantly lower potential to
deplete ozone than CFC-11. Plant or process modifications may be
required to allow use of blowing agents like HCFC-142b that have
significantly lower boiling points than CFC-11. HCFC-142b is subject to
the accelerated phase out rule (58 FR 65018).
(e) HCFC-22/HCFC-141b. The HCFC-22/HCFC-142b blend is acceptable as
a substitute for CFC-11 in rigid polyurethane and polyisocyanurate
laminated boardstock foam. HCFC-22 has an occupational exposure limit
(OEL) of 250 ppm, whereas HCFC-141b has an OEL of 1000 ppm.
(f) HCFC-22/HCFC-142b. HCFC-22/HCFC-142b blends are acceptable as a
substitute for CFC-11 in rigid polyurethane and polyisocyanurate
laminated boardstock foam. This blend offers an alternative with
significantly less potential to deplete ozone than CFC-11. Plant or
process modifications may be required to allow use of blowing agents
like HCFC-22 and HCFC-142b that have low boiling points than CFC-11.
(g) HCFC-141b/HCFC-123. The HCFC-141b/HCFC-123 blend is acceptable
as an alternative to CFC-11 in rigid polyurethane and polyisocyanurate
laminated boardstock foam. As noted above, HCFC-141b, because of its
commercial availability offers an immediate opportunity to replace CFC-
11. HCFC-123 has limited availability. However, because the ODP of
HCFC-123 is lower than that of HCFC-141b, the blend has a lower ODP
than HCFC-141b alone.
(h) HCFC-22/HCFC-141b. The HCFC-22/HCFC-142b blend is acceptable as
a substitute for CFC-11 in rigid polyurethane and polyisocyanurate
laminated boardstock foam. Because both components of the blend are
commercially available in large enough quantities to meet industry
demand, it offers a near-term vehicle for replacing CFC-11 in laminated
boardstock foams. HCFC-22 has an occupational exposure limit (OEL) of
250 ppm, whereas HCFC-141b has an OEL of 1000 ppm.
(i) HFC-134a. HFC-134a is acceptable as a substitute for CFC-11 in
rigid polyurethane and polyisocyanurate laminated boardstock foam. HFC-
134a offers the potential for a non-ozonedepleting alternative to CFC-
11 blowing agents in rigid polyurethane and polyisocyanurate laminated
boardstock foams. Plant modifications may be necessary to accommodate
the use of HFC-134a because its boiling point is lower than that of
CFC-11. In addition, the cost of HFC-134a is relatively high, and the
use of HFC-134a may cause significant increases in thermal
conductivity, with a concomitant loss in the insulating capacity of
foams blown with HFC-134a. HFC-134a also has a relatively high global
warming potential compared with other available alternatives.
(j) HFC-152a. HFC-152a is acceptable as a substitute for CFC-11 in
rigid polyurethane and polyisocyanurate laminated boardstock foam. HFC-
152a offers the potential for a non-ozonedepleting alternative to CFC-
11 blowing agents in rigid polyurethane and polyisocyanurate laminated
boardstock. Use of HFC-152a as a blowing agent in rigid polyurethane
and polyisocyanurate laminated boardstock foam has raised concern over
the potential for significant increases in thermal conductivity.
Process changes may be necessary to accommodate the use of HFC-152a,
and plant modifications may be necessary to manage its flammability.
Also, foams blown with HFC-152a will need to conform with building code
requirements that relate to flammable materials.
(k) Saturated light hydrocarbons C3-C6. Saturated Light
Hydrocarbons C3-C6 are acceptable as substitutes for CFC-11 in rigid
polyurethane and polyisocyanurate laminated boardstock foam. These
hydrocarbons have zero-ODP and zero-GWP. Plant or process modifications
may be necessary to accommodate the use of saturated light hydrocarbons
C3-C6. These materials also pose flammability concerns which may
require capital investment to manage. Foams blown with hydrocarbons
will need to conform with building code requirements that relate to
flammable materials. Finally, the thermal conductivity is greater than
CFC-11 blowing agents which may effect the thermal capacity of final
products. Saturated light hydrocarbons are VOCs and must be controlled
as such under Title I of the CAA.
(l) 2-Chloropropane. 2-Chloropropane is acceptable as a substitute
for CFC-11 in rigid polyurethane and polyisocyanurate laminated
boardstock foam. At present, because 2-chloropropane is a proprietary
process, its commercial availability may be limited. Moreover, 2-
chloropropane is flammable and its use may require extensive
modification of existing equipment.
(m) Carbon dioxide. Carbon dioxide is acceptable as a substitute
for CFC-11 in rigid polyurethane and polyisocyanurate laminated
boardstock foam.
(2) Polyurethane, rigid appliance foam. (a) HCFC-123. HCFC-123 (or
blends thereof), for the reasons described in the section on rigid
polyurethane and polyisocyanurate laminated boardstock, is acceptable
as an alternative to CFC-11 in rigid polyurethane appliance foam.
(b) HCFC-141b. HCFC-141b (or blends thereof), for the reasons
described in the section on rigid polyurethane and polyisocyanurate
laminated boardstock, is acceptable as an alternative to CFC-11 in
rigid polyurethane appliance foam. The Appliance Research Consortium
(ARC), a subsidiary of the Association of Home Appliance Manufacturers
(AHAM), convened an independent panel of toxicologists to evaluate the
risk of potential exposure from foods stored in refrigerators
manufactured with HCFC-141b as the blowing agent in the insulating
foam. The panel evaluated the same toxicological data available to EPA,
and concluded that the use of HCFC-141b in this intended application is
generally recognized as safe (GRAS) per section 201(s) of the Food,
Drug, and Cosmetic Act, 21 USC section 321(s).\1\
---------------------------------------------------------------------------
\1\Peter de la Cruz, Evaluation of HCFC-141b Potential Dietary
Exposure, Keller and Heckman, January, 1994.
---------------------------------------------------------------------------
(c) HCFC-22. HCFC-22 (or blends thereof), for reasons described in
the section on rigid polyurethane and polyisocyanurate laminated
boardstock, is acceptable as a substitute for CFC-11 in rigid
polyurethane appliance foam.
(d) HCFC-142b. HCFC-142b (or blends thereof) is acceptable as a
substitute for CFC-11 in rigid polyurethane appliance foam. HCFC-142b
offers an alternative with significantly less potential to deplete
stratospheric ozone than CFC-11. Nevertheless, certain technical
problems persist. Namely, plant modifications may be required to allow
the use of blowing agents like HCFC-142b that have low boiling points.
(e) HFC-134a. HFC-134a (or blends thereof), for the reasons
described in the section on rigid polyurethane and polyisocyanurate
laminated boardstock, is acceptable as an alternative to CFC-11 in
rigid polyurethane appliance foam.
(f) HFC-152a. HFC-152a (or blends thereof), for the reasons
described in the section on rigid polyurethane and polyisocyanurate
laminated boardstock, is acceptable as an alternative to CFC-11 in
rigid polyurethane appliance foam.
(g) Saturated light hydrocarbons C3-C6. Saturated light
hydrocarbons C3-C6 (or blends thereof) are acceptable as substitutes
for CFC-11 in rigid polyurethane appliance foam. Saturated light
hydrocarbons C3-C6 offer the potential of a non-ozone-depleting
alternative to the use of CFC-11 blowing agents in rigid polyurethane
appliance foam. Plant modifications may be necessary to accommodate the
flammability of Saturated Light Hydrocarbons C3-C6. In addition, the
potential for significant increases in thermal conductivity may reduce
insulating capacity. Foams blown with saturated light hydrocarbons C3-
C6 must conform with building code requirements that relate to
flammable materials. Saturated light hydrocarbons C3-C6 are VOCs and
will be subject to control as such under Title I of the CAA.
(h) Carbon dioxide. Carbon dioxide (or blends thereof) is
acceptable as a substitute for CFC-11 in rigid polyurethane appliance
foam.
(3) Rigid polyurethane commercial refrigeration foam, spray foam,
and sandwich panels. (a) HCFC-123. HCFC-123, for the reasons described
in the section on rigid polyurethane and polyisocyanurate laminated
boardstock, is acceptable as an alternative to CFC-11 and CFC-12 in
rigid polyurethane commercial refrigeration foam, spray foam, and
sandwich panels.
(b) HCFC-141b. HCFC-141b (or blends thereof), for the reasons
described in the section on rigid polyurethane and polyisocyanurate
laminated boardstock, is acceptable as an alternative to CFC-11 and
CFC-12 in rigid polyurethane commercial refrigeration foam, spray foam,
and sandwich panels.
(c) HCFC-22. HCFC-22 (or blends thereof) is acceptable as a
substitute for CFC-11 and CFC-12 in rigid polyurethane commercial
refrigeration foam, spray foam, and sandwich panels. HCFC-22 offers an
alternative with significantly less potential to deplete ozone than
either CFC-11 or CFC-12. However, significant process changes could be
necessary to accommodate the low boiling point of HCFC-22.
(d) HCFC-142b. HCFC-142b (or blends thereof), for the reasons
described in the section on rigid polyurethane and polyisocyanurate
laminated boardstock, is acceptable as an alternative to CFC-11 and
CFC-12 in rigid polyurethane commercial refrigeration foam, spray foam,
and sandwich panels.
(e) HFC-134a. HFC-134a (or blends thereof), for the reasons
described in the section on rigid polyurethane and polyisocyanurate
laminated boardstock, is acceptable as an alternative to CFC-11 and
CFC-12 in rigid polyurethane commercial refrigeration foam, spray foam,
and sandwich panels.
(f) HFC-152a. HFC-152a (or blends thereof), for the reasons
described in the section on rigid polyurethane and polyisocyanurate
laminated boardstock, is acceptable as an alternative to CFC-11 and
CFC-12 in rigid polyurethane commercial refrigeration foam, spray foam,
and sandwich panels.
(g) Saturated light hydrocarbons C3-C6. Saturated light
hydrocarbons C3-C6 (or blends thereof), for the reasons described in
the section on rigid polyurethane and polyisocyanurate laminated
boardstock, are acceptable alternative blowing agents for CFC-11 and
CFC-12 in rigid polyurethane commercial refrigeration foam, spray foam,
and sandwich panels.
(h) Carbon dioxide. Carbon dioxide (or blends thereof) is an
acceptable alternative blowing agent for CFC-11 in rigid polyurethane
commercial refrigeration foam, spray foam, and sandwich panels.
(4) Polyurethane slabstock and other foams. (a) HCFC-123. HCFC-123
(or blends thereof) is acceptable as an alternative to CFC-11 in rigid
polyurethane slabstock and other foams. From the standpoint of
technical feasibility, HCFC-123 represents a viable alternative to CFC-
11 as a potential blowing agent. More specifically, the physical
properties, thermal conductivity, and aging of foams blown with HCFC-
123 are similar to those blown with CFC-11. As a result, HCFC-123,
which has an ozone depleting potential significantly lower than that of
CFC-11, has the potential to replace CFC-11 in many applications.
Nonetheless, commercial availability of HCFC-123 is limited at present.
(b) HCFC-141b. HCFC-141b (or blends thereof) is acceptable as an
alternative to CFC-11 in rigid polyurethane slabstock and other foams.
Although its ODP of 0.11 is relatively high, HCFC-141b offers almost
immediate transition out of CFCs in this sector. Not only does HCFC-
141b offer a technically feasible alternative to CFC-11, it is
currently available in sufficient quantities to meet industry demand.
The use of HCFCs in polyurethane slabstock and other foams is subject
to further restriction under section 610 of the CAA, which banned the
use of class II substances in noninsulating foams after January 1,
1994.
(c) HCFC-22. HCFC-22 (or blends thereof) is acceptable as a
substitute for CFC-11 in rigid polyurethane slabstock and other foams.
HCFC-22 offers an alternative with significantly less potential to
deplete ozone than either CFC-11 or CFC-12. However, significant
process changes may be necessary to accommodate the low boiling point
of HCFC-22.
(d) HFC-134a. HFC-134a (or blends thereof), for the reasons
described in the section on rigid polyurethane and polyisocyanurate
laminated boardstock, is acceptable as an alternative to CFC-11 and
CFC-12 in rigid polyurethane slabstock and other foams.
(e) HFC-152a. HFC-152a (or blends thereof), for the reasons
described in the section on rigid polyurethane and polyisocyanurate
laminated boardstock, is acceptable as an alternative to CFC-11 and
CFC-12 in rigid polyurethane slabstock and other foams.
(f) Saturated light hydrocarbons C3-C6. Saturated light
hydrocarbons C3-C6 (or blends thereof), for the reasons described in
the section on rigid polyurethane and polyisocyanurate laminated
boardstock, are acceptable alternative blowing agents for CFC-11 and
CFC-12 in rigid polyurethane slabstock and other foams.
(g) Carbon Dioxide. Carbon dioxide (or blends thereof) is an
acceptable alternative blowing agent for CFC-11 and CFC-12 in rigid
polyurethane slabstock and other foams.
(5) Extruded Polystyrene Boardstock and Billet. (a) HCFC-22. HCFC-
22 is an acceptable alternative blowing agent for CFC-12 in extruded
polystyrene boardstock and billet foam. HCFC-22 offers an alternative
with significantly less potential to deplete ozone than CFC-12. HCFC-
22, however, has a relatively high permeation rate out of polystyrene,
thus affecting insulation performance. Users must be in compliance with
the section 610 Nonessential Products Containing Class II Substances
Ban.
(b) HCFC-142b. HCFC-142b is an acceptable alternative blowing agent
for CFC-12 in extruded polystyrene boardstock foam. HCFC-142b offers an
alternative with significantly less potential to deplete ozone than
either CFC-11 or CFC-12. Users must be in compliance with the section
610 Non-essential Products Containing Class II Substances Ban.
(c) HCFC-22/HCFC-142b. The HCFC-22/HCFC-142b blend is acceptable as
a substitute for CFC-12 in extruded polystyrene boardstock and billet
foam. The blend offers an alternative with significantly less potential
to deplete ozone than CFC-12. Users must be in compliance with section
610 Nonessential Products Containing Class II Substances.
(d) HFC-134a. HFC-134a is acceptable as a substitute for CFC-12 in
extruded polystyrene boardstock and billet foam. HFC-134a offers the
potential for a non-ozone-depleting alternative to CFC-12 blowing
agents in extruded polystyrene boardstock and billet foam. HFC-134a,
because of its low flammability and encouraging performance in
toxicological testing, exhibits definite advantages from the
standpoints of environmental risk and worker and consumer safety.
However, HFC-134a has relatively high thermal conductivity, is costly,
and has the potential to contribute to global warming. In addition, the
compound has poor solubility in polystyrene polymer, which could limit
its usefulness as an alternative blowing agent from a technical
standpoint. HFC-134a also has a relatively high global warming
potential compared to other available alternatives.
(e) HFC-152a. HFC-152a is acceptable as a substitute for CFC-12 in
extruded polystyrene boardstock and billet foam. HFC-152a offers the
potential for a non-ozone-depleting alternative to CFC-12 blowing
agents in extruded polystyrene boardstock. However, the high
flammability of HFC-152a when combined with its properties of high
thermal conductivity, low solubility in polystyrene polymer, and high
permeability through polystyrene limit the extent to which HFC-152a is
likely to replace CFC-12. Plant modifications may be needed to
accommodate the flammability of HFC-152a, and foams blown with HFC-152a
will need to conform with building code requirements that relate to
flammable materials.
(f) Saturated light hydrocarbons C3-C6. Saturated light
hydrocarbons C3-C6 are acceptable as substitutes for CFC-12 in
polystyrene boardstock and billet foam. Of the Saturated Light
Hydrocarbons C3-C6, pentane, isopentane, butane, and isobutane have
been demonstrated as feasible blowing agents in polystyrene. In fact,
saturated light hydrocarbons C3-C6 have been used for years in the
manufacture of extruded polystyrene sheet products. However, saturated
light hydrocarbons C3-C6 have several disadvantages as blowing agents
in extruded polystyrene boardstock and billet foam. Replacement of CFC-
12 blowing agents with Saturated Light Hydrocarbons C3-C6 may reduce
the insulating efficiency in this end-use. Controlling the flammability
of saturated light hydrocarbons C3-C6 may entail significant investment
in plant conversion to accommodate them as alternatives to CFC-12.
Foams blown with saturated light hydrocarbons C3-C6 will need to
conform with building code requirements that relate to flammable
materials. Finally, saturated light hydrocarbons C3-C6 are VOCs and
must be controlled as such under Title I of the CAA.
(g) HCFC-22/Saturated Light Hydrocarbons C3-C6. Blends of HCFC-22/
saturated light hydrocarbons C3-C6, for the reasons described and with
the caveats outlined above for HCFC-22 and Saturated Light Hydrocarbons
C3-C6, are acceptable substitutes for CFC-12 in extruded polystyrene
boardstock and billet foam.
(h) Carbon dioxide. Carbon dioxide is an acceptable alternative
blowing agent for CFC-12 in extruded polystyrene boardstock and billet
foam.
(6) Phenolic insulation board. (a) HCFC-141b. HCFC-141b, for the
reasons described in the section on rigid polyurethane and
polyisocyanurate laminated boardstock, is acceptable as an alternative
to CFC-11 and CFC-113 in phenolic insulation board.
(b) HCFC-142b. HCFC-142b, for the reasons described in the section
on rigid polyurethane and polyisocyanurate laminated boardstock, is
acceptable as an alternative to CFC-11 and CFC-113 in phenolic
insulation board.
(c) HCFC-22. HCFC-22, for the reasons described in the section on
rigid polyurethane commercial refrigeration foams, spray foams, and
sandwich panels, is acceptable as an alternative to CFC-11 and CFC-113
in phenolic insulation board.
(d) HCFC-22/HCFC-142b. Blends of HCFC-22/HCFC-142b, for reasons
described above and with the caveats outlined above for HCFC-22 and
HCFC-142b, are acceptable as an alternative to CFC-11 and CFC-113 in
phenolic insulation board.
(e) Saturated Light Hydrocarbons C3-C6. Saturated light
hydrocarbons C3-C6, for the reasons described in the section on rigid
polyurethane and polyisocyanurate laminated boardstock, are acceptable
alternatives to CFC-11 and CFC-113 in phenolic insulation board.
(f) HCFC-22/Saturated light hydrocarbons C3-C6. HCFC-22/Saturated
light hydrocarbon C3-C6 blends are acceptable as substitutes for CFC-11
and CFC-113 in phenolic insulation board. HCFC-22/saturated light
hydrocarbon C3-C6 blends offer an alternative with significantly less
potential to deplete ozone than either CFC-11 or CFC-113. However,
extensive plant modifications may be necessary to accommodate use of
these blends. In addition, there are concerns about the potential for
significant increases in thermal conductivity resulting from the
replacement of CFC-11 and CFC-113 with a blend. Also, foams blown with
saturated light hydrocarbons C3-C6 will need to conform with building
code requirements that relate to flammable materials. Saturated light
hydrocarbons C3-C6 are VOCs and must be controlled as such under Title
I of the CAA, and HCFC-22 is subject to the phase-out of Class II
compounds under sections 605 and 606 of the CAA.
(g) HFC-143a. HFC-143a is acceptable as a substitute for CFC-11 and
CFC-12 in phenolic insulation board. HFC-143a has a higher global
warming potential than other substitutes available.
(h) 2-Chloropropane 2-Chloropropane is acceptable as a substitute
for CFC-11 and CFC-12 in phenolic insulation board. At present, because
2-chloropropane is a proprietary technology. Moreover, 2-chloropropane
is flammable and its use may require extensive modification of existing
equipment.
(i) Carbon dioxide. Carbon dioxide is an acceptable alternative
blowing agent for CFC-11 and CFC-12 in phenolic insulation board.
(7) Flexible polyurethane foam. (a) Methylene chloride. Methylene
chloride (or blends thereof) is acceptable as a blowing agent in
flexible polyurethane foams. Methylene chloride is already used as an
auxiliary blowing agent in the manufacture of most flexible
polyurethane slabstock foams and has proven adequate in yielding foams
of many densities and degrees of softness. Replacement of CFC-11 or
methyl chloroform blowing agents with methylene chloride can reduce the
potential for stratospheric ozone depletion resulting from the
production of flexible polyurethane foams.
Nevertheless, there is concern over the potential health and safety
issues posed by methylene chloride. In fact, due to these concerns,
some local and regional restrictions apply to the use of methylene
chloride. To assess these risks in the application under discussion,
EPA used data collected by the Occupational Safety and Health
Administration (OSHA) for the proposed revision of the permissible
exposure level (PEL) for methylene chloride. The Agency's estimate for
total population risk for methylene chloride was based on average plant
emissions derived from OSHA's analysis, and while not negligible, was
within the range of existing Agency decisions on acceptable risk. For
further detail, refer to the background document entitled ``Risk Screen
on the Use of Substitutes for Class I Ozone-Depleting Substances:
Foams''.
In light of the results of Agency analysis, EPA decided to find
acceptable the use of methylene chloride subject to existing or future
restrictions because it will allow immediate transition from class I
substances in this end-use. Potential users should note that methylene
chloride use will be subject to future controls for hazardous air
pollutants under Title III section 112 of the CAA. In addition, use of
the compound must conform to all relevant workplace safety standards;
OSHA has proposed permissible exposure levels (PELs) for methylene
chloride of 25 ppm on a time-weighted average (TWA). Once such
additional controls have been adopted, use of this substitute must
comply with any other applicable requirements, such as state
restrictions. Use is also subject to waste disposal requirements under
RCRA.
(b) Acetone. Acetone (or blends thereof) is acceptable as a blowing
agent for flexible polyurethane foams. In those areas where methylene
chloride use is deemed unacceptable, acetone may provide another non-
ODP alternative to CFC-11 and methyl chloroform. All grades of flexible
polyurethane foam produced with CFCs can be produced using acetone as
an auxiliary blowing agent. Acetone does not have an ozone depletion
potential, and its global warming potential is negligible.
Nevertheless, acetone is highly flammable and its use requires
precautions to ensure safety to workers as prescribed by OSHA. In
addition, use of this compound is subject to various federal, state, or
local controls as a VOC under Title I of the CAA.
(c) HFC-134a. HFC-134a (or blends thereof) is acceptable as a
substitute for CFC-11 in flexible polyurethane foam. HFC-134a is a non-
ozone-depleting alternative to CFC-11 blowing agents in flexible
polyurethane foam. Plant modifications may be necessary to accommodate
the use of HFC-134a because its boiling point is lower than that of
CFC-11.
(d) HFC-152a. HFC-152a (or use thereof) is acceptable as a
substitute for CFC-11 in flexible polyurethane foam. HFC-152a is a non-
ozone-depleting alternative to CFC-11 blowing agents in flexible
polyurethane foam. Process changes may be necessary to accommodate the
use of HFC-152a, and plant modifications may be necessary to manage its
flammability.
(e) AB Technology. AB Technology is acceptable as an alternative
process in flexible polyurethane foams. The AB Technology generates
carbon monoxide as the chemical blowing agent. Precautions should be
taken to insure the safety of workers from exposure to elevated levels
of carbon monoxide, particularly at the latter phases of production
where ventilation is generally not as efficient as on the foam line.
OSHA has set a permissible exposure level (PEL) for carbon monoxide of
35 ppm on a time-weighted average (TWA) with a ceiling of 200 ppm.
(f) Carbon dioxide. Carbon dioxide (or blends thereof) is an
acceptable alternative process in flexible polyurethane foams.
(8) Polyurethane integral skin foams. (a) HCFC-123. HCFC-123 (or
blends thereof) is acceptable as an alternative to CFC-11 in integral
skin foams. The physical and chemical properties of HCFC-123 are
similar to CFC-11. As a result, HCFC-123, which has an ozone depleting
potential significantly lower than that of CFC-11, has the potential to
replace CFC-11 in many integral skin applications. Nonetheless,
commercial availability of HCFC-123 is limited at present. The use of
HCFC-123 in integral skin foams is subject to significant restriction
under section 610 of the CAA, which bans the use of class II substances
in noninsulating foams after January 1, 1994. The ban exempts only
certain integral skin foams used to provide for motor vehicle safety.
(b) HCFC-141b. HCFC-141b (or blends thereof) is acceptable as an
alternative to CFC-11 in integral skin foams. Although its ODP of 0.11
is relatively high, HCFC-141b offers an acceptable transition
substitute out of CFC-11 in integral skin foams. The use of HCFC-141b
in integral skin foams, however, is subject to significant restriction
under section 610 of the CAA, which banned the use of class II
substances in noninsulating foams after January 1, 1994. The ban
exempts only certain integral skin foams used to provide for motor
vehicle safety.
(c) HCFC-22. HCFC-22 (or blends thereof) is acceptable as a
substitute for CFC-11 in integral skin foam. HCFC-22 offers an
alternative with significantly less potential to deplete ozone than
CFC-11. However, process changes may be necessary to accommodate the
low boiling point of HCFC-22. The use of HCFC-22 in integral skin foams
is subject to significant restrictions under section 610 of the CAA,
which banned the use of class II substances in noninsulating foams
after January 1, 1994. The ban exempts only certain integral skin foams
used to provide for motor vehicle safety.
(d) HFC-134a. HFC-134a (or blends thereof) is acceptable as a
substitute for CFC-11 in polyurethane integral skin foam. HFC-134a is a
non-ozone-depleting alternative to CFC-11 blowing agents in
polyurethane integral skin foam. Plant or process modifications may be
necessary to accommodate the use of HFC-134a because its boiling point
is lower than that of CFC-11.
(e) HFC-152a. HFC-152a (or blends thereof) is acceptable as a
substitute for CFC-11 in polyurethane integral skin foam. HFC-152a is a
non-ozone-depleting alternative to CFC-11 blowing agents in
polyurethane integral skin. Plant or process changes may be necessary
to accommodate the use of HFC-152a, and plant modifications may be
necessary to manage its flammability. Also, foams blown with HFC-152a
will need to conform with any product safety requirements that relate
to flammable materials.
(f) Saturated light hydrocarbons C3-C6. Saturated light
hydrocarbons C3-C6 (or blends thereof) are acceptable as substitutes
for CFC-11 in integral skin foams. Saturated light hydrocarbons C3-C6
offer the possibility of a non-ODP replacement for CFC-11 in integral
skin foams. Plant or process modifications may be necessary to
accommodate the flammability of saturated light hydrocarbons C3-C6 and
to make the necessary technical and process modifications.
(g) Methylene chloride. Methylene chloride (or blends thereof) is
acceptable as a blowing agent in integral skin foam. See methylene
chloride discussion under Polyurethane Flexible Foams for additional
details on toxicity issues. Use is subject to waste disposal
requirements under RCRA.
(h) Carbon dioxide. Carbon dioxide (or blends thereof) is
acceptable as a blowing agent in integral skin foams.
(9) Extruded polystyrene sheet foam. (a) HFC-134a. HFC-134a (or
blends thereof) is acceptable as a substitute for CFC-12 in extruded
polystyrene sheet foam. HFC-134a is a non-ozone-depleting alternative
to CFC-12 blowing agents in polystyrene sheet foam.
(b) HFC-152a. HFC-152a (or blends thereof) is acceptable as a
substitute for CFC-12 in extruded polystyrene sheet foam. HFC-152a is a
non-ozone-depleting alternative to CFC-12 blowing agents in extruded
polystyrene sheet foams. The compound is commercially available and its
low molecular weight suggests that its blowing efficiency will be
double that of CFC-12. Plant or process modifications may be needed to
accommodate the flammability of HFC-152a.
(c) Saturated light hydrocarbons C3-C6. Saturated light
hydrocarbons C3-C6 (or blends thereof) are acceptable as substitutes
for CFC-12 in extruded polystyrene sheet foam. Saturated light
hydrocarbons C3-C6 offer the potential of a non-ozone-depleting
alternative to the use of CFC-12 blowing agents in extruded polystyrene
sheet. At present, pentane and butane are used extensively as blowing
agents in extruded polystyrene sheet. These compounds are widely
available at low cost and offer excellent solubility with the
polystyrene polymer.
(d) Carbon dioxide. Carbon dioxide (or blends thereof) is
acceptable as a substitute for CFC-12 in extruded polystyrene sheet
foam.
(10) Polyolefin foams. (a) HCFC-22. HCFC-22 is acceptable as a
substitute for CFC-11, CFC-12, and CFC-114 in polyolefin foams. HCFC-22
offers an alternative with significantly less potential to deplete
ozone than CFC-11, CFC-12, or CFC-114. Under the section 610 Non-
Essential Use Ban, HCFC use in polyolefin foams is restricted to
thermal insulating applications of polyethylene foams where such foam
is suitable in shape, thickness and design to be used as a product that
provides thermal insulation around pipes used for heating, plumbing,
refrigeration, or industrial process systems.
(b) HCFC-142b. HCFC-142b is acceptable as a substitute for CFC-11,
CFC-12, and CFC-114 in polyolefin foams. HCFC-142b offers an
alternative with significantly less potential to deplete ozone than
CFC-11, CFC-12, or CFC-114. Under the section 610 Non-Essential Use
Ban, HCFC use in polyolefin foams is restricted to thermal insulating
applications of polyethylene foams where such foam is suitable in
shape, thickness and design to be used as a product that provides
thermal insulation around pipes used for heating, plumbing,
refrigeration, or industrial process systems.
(c) HCFC-22/HCFC-142b. HCFC-22/HCFC-142b blends are acceptable, for
reasons described and the caveats outlined above, as a substitute for
CFC-11, CFC-12 and CFC-114 in polyolefin foam. Under the section 610
Non-Essential Use Ban, HCFC use in polyolefin foams is restricted to
thermal insulating applications of polyethylene foams where such foam
is suitable in shape, thickness and design to be used as a product that
provides thermal insulation around pipes used for heating, plumbing,
refrigeration, or industrial process systems.
(d) HFC-134a. HFC-134a is acceptable as a substitute for CFC-11,
CFC-12, and CFC-114 in polyolefin foams. HFC-134a offers the potential
for a non-ozone-depleting alternative to CFC-11, CFC-12, and CFC-114 in
polyolefin foams. HFC-134a, because of its low flammability and
encouraging performance in toxicological testing, exhibits definite
advantages from the standpoints of worker and consumer safety. HFC-134a
does, however, contribute to global warming.
(e) HFC-143a. HFC-143a is acceptable as a substitute for CFC-11,
CFC-12, and CFC-114 in polyolefin foams. HFC-143a has a higher global
warming potential than other acceptable substitutes in this end-use.
(f) HFC-152a. HFC-152a, for the reasons described in the section on
extruded polystyrene sheet foam, is acceptable as an alternative to
CFC-11, CFC-12, and CFC-114 in polyolefin foams. Plant or process
modifications may be needed to accommodate the flammability of HFC-
152a.
(g) Saturated light hydrocarbons C3-C6. Saturated light
hydrocarbons C3-C6 are acceptable as substitutes for CFC-11, CFC-12,
and CFC-114 in polyolefin foams.
(h) HCFC-22/Saturated light hydrocarbons C3-C6. HCFC-22/Saturated
light hydrocarbons C3-C6 blends, for the reasons described and with the
caveats outlined above, are acceptable substitutes for CFC-11, CFC-12
and CFC-114 in polyolefin foams. Under the section 610 Non-Essential
Use Ban, HCFC use in polyolefin foams is restricted to thermal
insulating applications of polyethylene foams where such foam is
suitable in shape, thickness and design to be used as a product that
provides thermal insulation around pipes used for heating, plumbing,
refrigeration, or industrial process systems.
(i) Carbon dioxide. Carbon dioxide is acceptable as a substitute
for CFC-11, CFC-12, and CFC-114 in polyolefin foams.
b. Unacceptable substitutes. The final rule listing a foam blowing
agent as unacceptable in a specific foam use sector constitutes a ban
on the use of that alternative to Class I compounds. This decision will
be effective 30 days after publication of this final rule.
(1) Polyolefin foams. The use of HCFC-141b (or blends thereof) is
unacceptable as an alternative blowing agent in polyolefin foams. HCFC-
141b has an ODP of 0.11, almost equivalent to that of methyl
chloroform, a Class I substance. The Agency believes that non-ozone
depleting alternatives are sufficiently available to render the use of
HCFC-141b unnecessary in this application.
F. Solvent Cleaning
1. Overview
On an ozone-depletion weighted basis, solvents constitute
approximately 15 percent of the chemicals targeted for phase-out under
the Montreal Protocol. In the U.S., the two class I chemicals used as
industrial solvents are CFC-113 (C2F3C13--trifluorotrichloroethane) and
methyl chloroform (C2H3C13--1,1,1-trichloroethane). The SNAP
determinations issued in the solvent cleaning sector focus on
substitutes for CFC-113 and methyl chloroform (MCF) when used in
industrial cleaning equipment, since this application comprises the
largest use of ozone-depleting solvents.
Other cleaning applications for ozone-depleting solvents exist as
well, such as in dry cleaning of textiles or in hand cleaning or
maintenance cleaning as a spray. In addition, these solvents are used
as bearer media (such as lubricant carriers), mold release agents,
component testing agents, or in other non-cleaning applications. CFC-11
is also occasionally used as a cleaning solvent in specialized
applications. For the reasons described earlier in this Preamble, the
Agency intends to exclude cleaning substitutes for CFC-113, MCF and
CFC-11 in these applications--with the exception of aerosol
substitutes--from the SNAP determinations at this time. As a result,
the Agency is not at this time issuing any determinations on
acceptability of such substitutes, and will neither approve nor
restrict their uses. Aerosol substitutes are covered in a separate
section of this Preamble.
Appendix B at the end of this Preamble lists in tabular form the
Agency's determinations on substitutes in the cleaning sector. These
listings are based on the risk screens described in the background
document entitled ``Risk Screen on the Use of Substitutes for Class I
Ozone-Depleting Substances: Solvent Cleaning'' and discussed in
associated supporting memoranda. The table includes as ``pending'' a
few substitutes for which the Agency has not yet issued determinations.
Vendors or users of cleaning substitutes not described in appendix B
should submit information on these uses, so that the Agency can review
them and issue a SNAP determination.
The three major end uses that in the past employed CFC-113 and MCF
are metals cleaning, electronics cleaning, and precision cleaning.
Metals cleaning applications usually involve removing cutting oils and
residual metal filings. This sector relies principally on MCF as a
cleaning solvent. In contrast, the electronics industry uses
principally CFC-113, for instance, to remove flux residues left after
mounting parts on printed circuit boards. Precision cleaning also uses
mostly CFC-113. This last application comprises a broad category of
industrial cleaning operations and can cover uses ranging from
preparation of pacemakers to manufacture of direct access storage
devices (DASDs) for computers. The following sections present
substitutes for CFC-113 and MCF in these three end uses and discuss the
acceptability listings presented in appendix B.
2. Substitutes in Solvents Cleaning
a. Hydrochlorofluorocarbons (HCFCs). HCFC-141b or HCFC-141b blends
with alcohols are the principal HCFC alternative solvents to CFC-113/
MCF cleaning. These alternatives can be used in vapor degreasing
equipment, principally for electronics or precision cleaning, and in
some cases existing CFC-113 or MCF equipment can be retrofitted for use
with HCFC-141b alternatives. From an environmental standpoint, the
critical characteristic of HCFC-141b is that it has a relatively high
ODP--0.11--the highest of all the HCFCs.
Another HCFC, HCFC-123, is generally not considered to have
widespread application as a cleaner. Although this HCFC has the
capacity to remove many soils, it is such an aggressive cleaner that it
frequently degrades the surface of the part being cleaned. The company-
set AEL for HCFC-123 was recently raised from 10ppm to 30ppm based on
new toxicity findings. These new data mean that the exposure limit
could be met with existing equipment, and the Agency intends to list
HCFC-123 under separate rule-making as acceptable subject to adherence
to the exposure limit.
HCFC-225, a third HCFC, is widely viewed as having potential as a
cleaning agent, especially for manufacture and maintenance of precision
parts and equipment. However, this chemical is not yet in widespread
production or use and is only now starting to be commercially
available. Preliminary toxicity findings suggest that of the two HCFC-
225 isomers, HCFC-225ca and HCFC-225cb, toxicity concerns associated
with the ca-isomer may warrant a comparatively low company-set
occupational exposure limit. As a result, EPA intends under separate
rule-making to propose HCFC-225 as acceptable subject to adherence to
this limit. The Agency anticipates that companies will readily be able
to meet this requirement since the ca-isomer is sold commercially in a
blend with the less toxic cb-isomer. In addition, equipment using HCFC-
225 is usually designed for precision operations and has inherently low
emissions.
b. Semi-aqueous cleaners. Semi-aqueous cleaners are alternatives
for cleaning in all three sectors. These cleaners employ hydrocarbons/
surfactants either emulsified in water solutions or applied in
concentrated form and then rinsed with water. Since both approaches
involve water as part of the formulation, the system is commonly
referred to as ``semi-aqueous.'' The principal categories of chemicals
used in these formulations are terpenes, C6-C20 petroleum hydrocarbons
(both naturally or synthetically derived), or oxygenated organic
solvents (such as alcohols). An extensive discussion of various semi-
aqueous cleaning alternatives may be found in the Industry Cooperative
for Ozone Layer Protection (ICOLP) documents on the subject. Users can
obtain these documents from the EPA.
c. Aqueous cleaners. Aqueous cleaners, unlike semi-aqueous, uses
water as the primary solvent. These formulations are used mostly for
metals cleaning, but companies are beginning to explore options using
these substitutes in other cleaning applications. In aqueous
formulations, detergents and surfactants are combined in water with a
variety of additives such as organic solvents (e.g., high-boiling point
alcohols), builders, saponifiers, inhibitors, emulsifiers, pH buffers
and antifoaming agents. The cleaning process is comparable to that used
in semiaqueous applications and consists of combinations of a wash
phase, a rinse phase, and a drying phase. An important difference is
that the wash tank is frequently heated to improve soil removal. The
final step, drying, is separate from the cleaning step and can be
accomplished by use of heat or a drying agent. These alternatives are
discussed extensively in the ICOLP documents.
d. Straight organic solvent cleaning. Organic solvents can be used
to replace CFC-113 and MCF in certain cleaning operations. This
classification is defined to include terpenes, C6-C20 petroleum
hydrocarbons (both naturally and synthetically derived), and oxygenated
organic solvents such as alcohols, ethers (including propylene glycol
ethers), esters and ketones. These compounds are commonly used in
solvent tanks at room temperature, although the solvents can also be
used in-line cleaning systems or be heated to increase solvency power.
If heated, the solvents must be used in equipment designed to control
vapor losses.
These solvents, unlike class I and II compounds, do not contribute
to stratospheric ozone depletion, and generally have short atmospheric
lifetimes. Yet many of the organic solvents are regulated as VOCs
because they can contribute to ground-level ozone formation. In
addition, certain of the organic solvents are toxic to human health and
are subject to waste handling standards under the Resource Conservation
and Recovery Act (RCRA) and to workplace standards set by Occupational
Safety and Health Administration (OSHA). For example, xylene and
toluene may be used as substitutes but are, once they become wastes,
regulated under RCRA as listed or characteristic wastes.
e. Other chlorinated solvents. In addition to MCF and CFC-113, the
three other commonly used chlorinated solvents are trichloroethylene
(``TCE''), methylene chloride (``meth''), and perchloroethylene
(``perc''). Unlike MCF and CFC-113, these chlorinated solvents have
very short atmospheric lifetimes and are not considered to contribute
to ozone depletion. However, all three have known toxicity problems and
are regulated as Hazardous Air Pollutants under section 112 of title
III of the Clean Air Act. They are also subject to waste handling
standards under RCRA and to workplace standards set by OSHA.
Additionally, TCE and perc exhibit photochemical reactivity, and are
regulated as smog precursors.
The phaseout of CFC-113 and MCF has prompted a renewed interest in
meth, TCE, and perc, despite these toxicity concerns. The three
solvents are mostly viewed as potential metal cleaning substitutes,
especially since they can be used in conventional vapor degreasing
equipment. In fact, these three solvents were the preferred industrial
solvents until concerns about their toxicity and anticipated lowering
of the OSHA Permissible Exposure Limits (PELs) resulted in a switch by
some users to MCF.
In response to such concerns, equipment vendors have now developed
equipment for using these solvents that significantly limit their
emissions. The availability of such equipment has prompted
environmental agencies in other western countries, such as Germany, to
relax restrictions on the use of these chemicals. Such equipment,
although expensive, can now be purchased in the United States.
f. No-clean alternatives. No-clean alternatives involve the use of
fluxes or cutting oils that need not be removed after the manufactured
part is fully formed. It offers an efficient solution to the cleaning
problem, since it sidesteps the need for cleaning altogether. This type
of substitute represents one of the few process changes possible in the
solvents cleaning sector. Water-removable products are products where
the soils or fluxes can be removed using water as opposed to other
types of chemical solvents. In electronics cleaning, where these two
approaches are in more widespread use, no-clean or water-removable
alternatives rely either on special fluxes or on a soldering process
that eliminates or reduces the residues otherwise removed through the
cleaning step.
In metal preparations, an increasing common process change is to
use vanishing oils. These oils are refined mineral spirits, usually
odorless, that flash off after the metal forming step is completed thus
eliminating the need for cleaning. Technically, this process can be
referred to as a ``no-clean'' process, although that term is usually
reserved for electronics manufacture.
g. Perfluorocarbons. Perfluorocarbons (PFCs) are fully fluorinated
compounds, unlike either CFCs, HCFCs or HFCs. Perfluorocarbons
presently employed or being investigated for commercial applications
for cleaning are C5F12, C6F12, C6F14, C7F16, C8F18, C5F11NO, C6F13NO,
C7F15NO, and C8F16.
These compounds are being discussed as part of innovative cleaning
and drying systems to replace ozone-depleting solvents used in
cleaning. These systems would use an aqueous or solvent cleaner bath
with PFCs for rinsing and/or drying. Although the PFCs technically are
being used as drying agents in this system, it is due to the
replacement of CFC-113 as a cleaner that the PFCs are being used, which
is why PFCs are addressed in the solvent cleaning sector. PFCs also
have solvent displacement properties (including for displacement of
water), that may make their use necessary. Although these systems have
the technical potential to meet a number of cleaning needs, the expense
of the PFCs may limit widespread commercial interest in systems that
use these compounds.
The environmental characteristics of concern for these compounds
are high global warming potential (5,000-10,000 times greater than
CO2) and long atmospheric lifetimes (3,000-5,000 years). Although
the actual contributions to global warming depend upon the quantities
of PFCs emitted, the warming effects of PFCs are essentially
irreversible. In other respects, PFCs are benign and are generally
nontoxic, nonflammable, and do not contribute to ground-level ozone
formation. Environmental concerns associated with use of PFCs are
discussed in the comment response section of this preamble, section
III.D. Technology for containment and recycling of PFCs is commercially
available and is recommended by manufacturers to offset any possible
adverse environmental effects.
h. Monochlorotoluene/benzotrifluorides. Monochlorotoluene and
benzotrifluorides are of commercial interest as solvent substitutes in
a variety of cleaning applications. These compounds can be used either
in isolation or in various mixtures, depending on desired chemical
properties. The Agency is still receiving toxicity and exposure
information on these formulations and will issue a SNAP determination
for these substitutes when SNAP review is complete.
i. Volatile methyl siloxanes. Cyclic and linear volatile methyl
siloxanes (VMSs) are currently undergoing investigation for use as
substitutes for class I compounds in metals, electronics and precision
cleaning. Because of their chemical properties, these compounds show
promise as substitutes for cleaning precision guidance equipment in the
defense and aerospace industries. In addition, the volatile methyl
siloxanes have high purity and are therefore relatively easy to recover
and recycle. In the cleaning system using VMSs, the fluids are used to
clean parts in a closed header system using a totally enclosed process.
The parts are drained and then dried using vacuum baking.
j. Supercritical fluid cleaning, plasma cleaning, UV-ozone
cleaning. Supercritical fluid cleaning, plasma cleaning and UV-ozone
cleaning are all three high-technology methods of cleaning parts. These
substitutes are mostly of interest for cleaning electronic parts or for
precision cleaning, although supercritical carbon dioxide is being
investigated for metal cleaning applications as well.
k. Dibromomethane. The Agency has received notification that
dibromomethane (also referred to as methylene bromide) can be used as a
substitute cleaning agent. This chemical has an ozone depletion
potential of .17, although it is not yet listed under the Clean Air
Act. In addition, dibromomethane is believed to be more toxic than
methylene chloride, although toxicity studies are scarce since
industrial applications in the past have been limited. As a result, the
Agency intends to propose this substitute as unacceptable in a separate
rule-making.
l. HFC-4310mee. HFC-4310mee will soon be commercially available as
a solvent cleaning agent. The Agency has received preliminary data on
this chemical, and anticipates that its use will be limited due to
global warming concerns to applications where it can replace longer-
lived PFCs or where its special chemical properties make it the only
viable substitute for a class I or II compound. This chemical will be
undergoing review under the Premanufacture Notice program of the Toxic
Substances Control Act.
Other HFCs are also being developed for solvent usage, although
their composition is still proprietary.
3. Comment Response
The majority of public comments received on the proposed solvents
cleaning SNAP decisions focused on the determinations for
perfluorocarbons (PFCs) and for chlorinated solvents. Most commenters
on PFCs requested that the Agency expand the acceptability
determination for PFCs to parts other than computer components, as
stated in the SNAP Notice of Proposed Rule-Making (NPRM). Although many
commenters agreed that a measure of control due to global warming
effects was necessary, several companies described in detail situations
where PFCs are believed to be the only viable alternative to CFC-113
and methyl chloroform. The Agency agrees with these commenters, and the
final SNAP determination lists the PFCs as acceptable in all cases
where no other alternative meets performance or safety standards. This
approach does not diverge significantly from that described in the
NPRM, in which EPA noted its intention to examine the possibility that
PFCs may be necessary for cleaning other parts in addition to computer
components.
Opinions on the chlorinated solvents diverged widely. A number of
commenters disagreed with the Agency's decision to list these chemicals
as acceptable substitutes for solvents cleaning. This viewpoint was
countered by other commenters who strongly agreed with the continuing
need to use chlorinated solvents. The Agency has not altered its
decision on these chemicals, and remains convinced that with
responsible control measures and housekeeping practices, potential
risks from these solvents can be significantly reduced and that overall
risks to human health and the environment will not increase
significantly as a result of substitution.
4. Listing Decisions
a. Acceptable substitutes. (1) Metals cleaning. (a) Semi-aqueous/
aqueous cleaners. Semi-aqueous and aqueous cleaners are acceptable
substitutes for CFC-113 and MCF in metals cleaning. The determinations
in this action cover semi-aqueous cleaners using terpenes, petroleum
hydrocarbons, and alcohols. To complete its modeling of the ability of
aqueous and semi-aqueous substitutes to replace CFC-113 and MCF in
existing applications, the Agency examined their ability to meet
cleaning requirements in the metals cleaning sector. Each of these
alternatives has the potential to service as much as 70 percent of the
metals cleaning market. To date, companies have shown the greatest
interest in aqueous formulations for metals cleaning, which is why the
Agency has reviewed this option in its first round of SNAP
determinations.
Concern over the water-based cleaners has historically focussed on
the potential for adverse effects on aquatic life following discharge
of wastewaters to surface water bodies. Examples of these effects
include death to aquatic microorganisms, fish teratogenicity, or
ecosystem effects such as inhibition of algal growth or
bioconcentration. In this case, the Agency wanted to ensure that, in
restricting the use of CFC-113 and methyl chloroform, it would not
simply be replacing risks from air emissions with equal risks from
contaminated water effluent.
To complete its risk analysis for the aqueous and semi-aqueous
formulations, the Agency developed a screening methodology designed to
characterize risks presented by typical manufacturing setups using
these formulations. The diversity of chemicals used in aqueous and
semi-aqueous cleaning complicated this undertaking. To complete its
screen, the Agency projected concentrations in water for the most toxic
chemical that could be used in the water-based formulations. These
concentrations were based on the maximum possible concentration in the
formulation and case studies documenting actual release profiles for
several sample processes. The predicted concentrations obtained using
this approach were then compared with toxicity values for this
``worst'' chemical.
This analysis suggests that most risks presented by use of water-
based cleaners can be controlled by standard process management
practices (e.g., planned discard schedules for wash and rinse solutions
in cleaner tanks) and by adhering to existing requirements for
wastewater treatment imposed by municipal or state authorities. This
screening approach, although it does not examine the toxicity of each
chemical and mixture or project exposures for each possible
formulation, does provide adequate perspective on the risks of these
compounds compared with risks from continued use of CFCs.
Although the Agency is listing water-based substitutes as
acceptable, it urges companies to install systems that permit re-use
and recycling of the formulation wherever possible to limit discharge
of these chemicals. This step can offer both important benefits to
aquatic systems as well as reduce operating costs of cleaning systems.
Users should also note that EPA is preparing new effluent
limitations and standards that will affect metals cleaning under the
Clean Water Act for the Metal Products and Machinery sector. These
standards, the first portion of which is expected to be issued in
November 1994, will address any remaining uncontrolled risks deriving
from the use of water-based cleaners in this industry. Phase I covers
sectors such as stationary industrial equipment, hardware, and
aircraft. Phase II, to be issued later, covers among other sectors
manufacture, rebuild, or maintenance of buses, trucks, railroads, and
shipbuilding.
(b) Straight organic solvent cleaning. Straight organic solvent
cleaning is an acceptable substitute for CFC-113 and MCF in the metals
cleaning sector. This acceptability determination extends to organic
solvents used as individual chemicals as well as in combinations.
Although these compounds can be toxic to human health and are
considered VOCs, the Agency's risk screen shows that these risks can be
addressed through existing regulatory controls. In occupational
settings where toxicity is a concern, such as for acetone or for
certain ketones, OSHA has set PELs designed to control risks. One class
of organic solvents about which there has recently been increased
concern for possible health effects is glycol ethers. However, the
glycol ethers identified in this case are ethylene glycol ethers,
whereas for solvent cleaning purposes companies customarily use
propylene glycol ethers. Propylene glycol ethers are generally not
believed to exhibit the same degree of toxicity as the ethylene glycol
ethers. Controls also exist for sources of VOC emissions and for
handling of the organic solvents as hazardous wastes under RCRA.
Regulatory standards are not the only method of mitigating the
environmental effects of these chemicals. Many manufacturers and
distributors of these solvents have instituted programs or can refer
companies to programs that will reclaim and process spent solvent--
either on or off-site--for further use. The Agency encourages companies
using organic solvents to seek out such programs. In addition,
companies should consider the principles of pollution prevention when
instituting cleaning with organic solvents and adopt emissions control
measures such as appropriate freeboard and automated hoists that will
reduce pollution at its source.
(c) Other chlorinated solvents. Trichloroethylene (TCE),
perchloroethylene (perc) and methylene chloride (meth) are all
acceptable substitutes for CFC-113 and MCF in the metals cleaning
sector. These alternatives have the chemical properties to meet the
cleaning needs of up to 80 percent of the metals cleaning sector,
although the Agency anticipates that the actual market share for the
non-ozone-depleting chlorinated solvents will not expand to the maximum
extent feasible. Because of the high toxicity of these compounds, they
have the potential to pose risks to workers and residents in nearby
communities. However, the Agency's analysis of use of these compounds
as cleaning agents indicates that these risks can be controlled by
adhering to existing regulatory standards. OSHA has determined, for
instance, that it is possible to use these solvents in a manner that
minimizes risks to workers. To reach this conclusion, OSHA conducted
extensive analyses of the toxicity and technical feasibility of using
perchloroethylene, trichloroethylene, or methylene chloride (54 FR
2329-2984, January 19, 1989, and 56 FR 57036-57141, November 7, 1991).
OSHA found that the new PEL of 50 ppm for trichloroethylene was
feasible in metal cleaning operations (54 FR 2433) and after conducting
an extensive study of metal degreasing control technologies, the
National Institute of Occupational Safety and Health concluded that an
exposure limit of 25 ppm for TCE could also be achieved. More recently,
in its proposed standard for methylene chloride, OSHA found that a PEL
of 25 ppm is technically feasible during metal cleaning operations with
the use of appropriate local exhaust ventilation and work practices.
In addition, these solvents are all listed as hazardous wastes
under RCRA (F001, U080, U210, U228) and thus must comply with
applicable RCRA waste disposal requirements. The SNAP risk screen did
note the potential for adverse effects without additional controls.
However, the Agency is in the process of addressing residual risks to
the general population through releases to air under section 112 of the
Clean Air Act. Section 112 requires EPA to establish Maximum Achievable
Control Technology (MACT) standards for use of Hazardous Air Pollutants
(HAPs). All three non-OD chlorinated solvents are listed as HAPs, and
the Agency issued a proposal describing MACT rules governing their use
in industrial cleaning in November 1993. The final regulation is
expected to be issued by the end of 1994.
Finally, through the voluntary ``33/50'' pollution prevention
program, the EPA is encouraging companies to decrease emissions of TCE,
perc, and meth, in addition to 14 other specific chemicals. Companies
participating in this program voluntarily commit to decreasing
emissions 33 percent by the end of 1992 and 50 percent by the end of
1995, using pollution prevention strategies. The Agency is committed in
the long term to urge companies to participate in pollution prevention
programs such as 33/50, and to continue to find new ways to use and
emit less polluting and lower toxicity compounds. EPA urges even
companies not participating in the 33/50 program to explore and adopt
housekeeping practices, chemical handling procedures, and equipment
configurations that lead to lower chemical consumption.
(d) Supercritical carbon dioxide. Supercritical carbon dioxide is
acceptable as a substitute for CFC-113 and MCF in the metals cleaning
sector. The Agency's risk screen did not identify any environmental
effects with significant concerns for this substitute.
(e) Vanishing oils. Vanishing oils are acceptable substitutes for
CFC-113 and MCF in the metals cleaning sector. Although these materials
are VOCs, extensive regulations exist at the Federal, state, and local
level to control any new VOC uses. In addition, newer vanishing oils
often have higher flashpoints, enabling them to be flashed and captured
in ovens.
(f) Volatile methyl siloxanes (dodecamethylcyclohexasiloxane,
hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane).
The volatile methyl siloxanes dodecamethylcyclohexasiloxane,
hexamethyldisiloxane, octamethyltrisiloxane, and
decamethyltetrasiloxane are acceptable substitutes for CFC-113 and MCF
in the metals cleaning sector. The Agency's risk screen for these
chemicals indicated that exposure to these substitutes are generally
below levels that would raise concern for health risks. Two of the
volatile methyl siloxanes, octamethylcyclotetrasiloxane and
decamethylcyclopentasiloxane, have low company-set exposure limits, and
these chemicals will be handled under a separate rulemaking.
(2) Electronics cleaning. a. (Semi-aqueous/aqueous cleaners).Semi-
aqueous and aqueous cleaners are acceptable substitutes for CFC-113 and
MCF in electronics cleaning. The justification for this determination
is described in the section on metals cleaning. In this case, the
Agency estimated that up to 80 percent of the cleaning market could be
captured by semi-aqueous cleaners and that up to 60 percent of the
market could be served by aqueous cleaners. As in metals cleaning, the
Agency urges companies to adopt pollution prevention practices and to
select formulations with low overall toxicity.
Effluent limitations and standards that affect use of water-based
formulations in the electronics cleaning sector will be proposed under
the Clean Water Act for the Phase I Metal Products and Machinery sector
by November 1994. Phase I includes electronic equipment along with
other manufacturing areas such as aerospace, hardware and mobile
industrial equipment. Phase II, to be issued later, covers household
and office equipment in addition to sectors such as motor vehicles and
shipbuilding.
(b) No-clean substitutes. No-clean processes are acceptable
substitutes for CFC-113 and MCF in electronics cleaning. The Agency's
analysis estimates that, over time, as much as seventy percent of the
electronics cleaning market could switch to no-clean processes--a
projection that is borne out by the high degree of interest shown by
electronics companies in these substitutes.
Concerns for risks deriving from use of no-clean processes focus
primarily on worker safety. To examine these risks, the Agency looked
at critical factors that distinguish no-clean processes from
conventional electronics assembly. These differences center on changes
in the proportions of chemicals used in formulations, rather than on
differences in the identity of chemicals selected. The analysis
determined that occupational risks deriving from these differences are
already well-documented and controlled, for example, through
requirements specified on key Materials Safety Data Sheets and existing
workplace regulations implemented by OSHA.
Additionally, the shifts in proportions of chemicals used in the
formulation result in less waste than is normally generated through the
traditional manufacturing process, resulting in a lower probability of
overall adverse effects to the general population. The Agency also
investigated the production of waste before and after the actual
cleaning process and found that waste generation at these points in the
production process would not be greater than what is seen with CFC-113
or MCF use.
This acceptability listing also applies to water-removable fluxes
and inert gas soldering.
(c) Straight organic solvent cleaning. Straight organic solvent
cleaning is an acceptable substitute for CFC-113 and MCF in the
electronics cleaning sector. This acceptability determination extends
to organic solvents used as individual chemicals as well as in
combinations. The Agency's justification for this decision is described
in the section on acceptable substitutes for metals cleaning.
(d) Other chlorinated solvents. Trichloroethylene (TCE),
perchloroethylene (perc) and methylene chloride (meth) are all
acceptable substitutes for CFC-113 and MCF in the electronics cleaning
sector. The reasons for this decision are described in the metals
cleaning discussion. Although these solvents have not received as much
commercial interest for electronics cleaning as for metals cleaning
applications, the Agency did receive a request to review these
chemicals for electronics cleaning.
Although the Agency's risk screen focused on use of these chemicals
in metals cleaning operations, the screen suggests that release
profiles for these chemicals in electronics cleaning will be either the
same or lower. As a result, the Agency has reached the same conclusion
with respect to electronics cleaning as in the metals cleaning
analysis, namely that any risks due to the inherent toxicity of these
chemicals could be controlled by existing and future regulatory
standards.
(e) Supercritical fluid cleaning, plasma cleaning, UV-ozone
cleaning. Supercritical fluid cleaning, plasma cleaning, UV-ozone
cleaning are all acceptable as substitutes for CFC-113 and MCF in
electronics cleaning. The Agency did not identify any environmental
issues associated with use of these substitutes. While ozone is
hazardous to human health, OSHA has already set standards for use of
this compound in the workplace.
(f) Volatile methyl siloxanes (dodecamethylcyclohexasiloxane,
hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane).
The volatile methyl siloxanes dodecamethylcyclohexasiloxane,
hexamethyldisiloxane, octamethyltrisiloxane, and
decamethyltetrasiloxane are acceptable substitutes for CFC-113 and MCF
in the electronics cleaning sector. The Agency's risk screen for these
chemicals indicated that exposure to these substitutes are generally
below levels that would raise concern for health risks. Two of the
volatile methyl siloxanes, octamethylcyclotetrasiloxane and
decamethylcyclopentasiloxane, have low company-set exposure limits, and
these chemicals will be handled under a separate rule-making.
(3) Precision cleaning. (a) Semi-aqueous/aqueous cleaners. Semi-
aqueous and aqueous cleaners are acceptable substitutes for CFC-113 and
MCF in precision cleaning. The reasons for this decision are the same
as those described in the metals cleaning section. Each of these
alternatives has the potential to service approximately 65 percent of
the precision cleaning market. This figure may overestimate the
technical potential for water-based cleaners in this sector, since this
end use sector faces the greatest technical constraints in implementing
new cleaning alternatives.
The Agency did not specifically examine risks from water-based
formulations used in precision cleaning since the processes are
typically either similar to those used in metals cleaning or have lower
throughputs and therefore fewer discharges. Therefore, the analysis
assumed that these risks from precision cleaning would be either
comparable to or less than risks associated with use of water-based
formulations for metals cleaning.
(b) Other chlorinated solvents. Other chlorinated solvents are
acceptable substitutes for CFC-113 and MCF in precision cleaning. The
reasons for this decision are described in the section on metals
cleaning. For the analysis of risks from these substitutes in the
precision cleaning end use sector, the Agency made the same assumptions
as in its analysis for electronics cleaning applications of water-based
formulations, namely that exposures would be equal to or less than
exposures in the metals cleaning sector since the processes for
precision cleaning are similar or even of lower emissions than those
for metals cleaning. Consequently, the Agency believes that risks would
also be either equivalent or lower.
(c) Straight organic solvent cleaning. Straight organic solvent
cleaning is an acceptable substitute for CFC-113 and MCF in precision
cleaning. This acceptability determination extends to organic solvents
used as individual chemicals as well as in combinations. The Agency's
justification for this decision is described in the section on
acceptable substitutes for metals cleaning.
(d) Supercritical fluid cleaning, plasma cleaning, UV-ozone
cleaning. Supercritical fluid cleaning, plasma cleaning, UV-ozone
cleaning are all acceptable as substitutes for CFC-113 and MCF in
precision cleaning. The Agency did not identify any environmental
issues associated with use of these substitutes. While ozone is
hazardous to human health, OSHA has already set standards for use of
this compound in the workplace.
(e) Volatile Methyl Siloxanes (dodecamethylcyclohexasiloxane,
hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane).
The volatile methyl siloxanes dodecamethylcyclohexasiloxane,
hexamethyldisiloxane, octamethyltrisiloxane, and
decamethyltetrasiloxane are acceptable substitutes for CFC-113 and MCF
in the precision cleaning sector. The Agency's risk screen for these
chemicals indicated that exposure to these substitutes are generally
below levels that would raise concern for health risks. Two of the
volatile methyl siloxanes, octamethylcyclotetrasiloxane and
decamethylcyclopentasiloxane, have low company-set exposure limits, and
these chemicals will be handled under a separate rule-making.
b. Substitutes acceptable subject to use conditions. (None).
c. Substitutes acceptable subject to narrowed use limits. (1)
Metals Cleaning. (None). (2) Electronics Cleaning. (a)
Perfluorocarbons. Perfluorocarbons (PFCs) are acceptable substitutes
for CFC-113 and MCF in the electronics cleaning sector for high-
performance, precision-engineering cleaning applications only where
reasonable efforts have been made to ascertain that other alternatives
are not technically feasible due to performance or safety requirements.
PFCs covered by this determination are C5F12, C6F12, C6F14, C7F16,
C8F18, C5F11NO, C6F13NO, C7F15NO, and C8F16O. The uses of PFCs in
solvent cleaning are restricted due to global warming concerns. PFCs
display intrinsic properties that point to their potential to be
contributors to global warming. All PFCs, for instance, have very long
atmospheric lifetimes. As an example, C5F12 (perfluoropentane) has a
lifetime of approximately 4,100 years. This means that for practical
purposes, any global warming effects from PFCs are irreversible. In
contrast, the lifetime of CFC-113 is, at 110 years, 40 times smaller.
Since greenhouse gases come from many diverse sources, even small
emissions of PFCs warrant controls if global warming is to be
successfully mitigated. The risk screen for the solvent cleaning sector
discusses the atmospheric properties of PFCs and provides a more
detailed discussion of why PFCs merit being listed as acceptable only
for narrowed uses.
Despite concerns about the global warming potential of PFCs, the
Agency has listed this niche application as an acceptable use of
perfluorocarbons because, for certain high-performance, precision-
engineered components and equipment, a PFC-based cleaning system may be
the only viable alternative available to replace use of class I or II
compounds.
The characteristics of components or equipment that may require
PFC-based cleaning are if the part:
Requires extremely low levels of remaining particulate and
residue for adequate performance (as opposed to cosmetic appearance).
Possesses complex geometric configurations and or
capillary spaces (as small as 1 micron) which greatly hinder cleaning
and drying.
Contains or is made of materials sensitive to corrosion,
oxidation or other damage from water (such as ceramics, gallium
arsenide, silicon nitride, or magnesium), where that damage would
degrade subsequent performance of the product.
Contains temperature-sensitive materials that cannot
maintain their integrity at the high drying temperatures of alternative
systems.
Contains materials that are hydrophilic or otherwise
impaired by contact with water.
Is extremely fragile, requiring the use of a low
viscosity, very low surface tension fluid.
Is contaminated with specialized halogenated lubricants or
damping fluids such as perfluoropolyethers.
Is a low-volume prototype under development for research,
testing and evaluation purposes.
Users should note that the presence of one of these parameters
alone does not necessarily indicate the need to use a PFC. For
instance, a water-sensitive part could potentially also be cleaned
using a solvent wash, solvent rinse without PFCs.
Examples of components where PFCs may be necessary are:
Precision optical and electro-optical systems such as
components for highpowered lasers or weapon targeting systems.
Specialized electrical, semiconductor and electronic
components, connectors and assemblies such as precision electronic
components used for military and avionics applications.
Sensitive medical devices and medical equipment components
such as electronic circuitry for pacemakers (does not include
prosthetic devices).
Precision telecommunications and communications components
such as microwave hybrid components for electronic warfare.
High-performance computer components and computer electro-
mechanical assemblies such as direct access storage devices.
Other examples are listed in the section on precision cleaning.
Examples of parts where alternatives other than PFCs exist are
electronic parts for low-value, mass-produced consumer or standard
machined metal parts.
A specific example under electronics cleaning where PFCs may be
necessary exists in manufacture of certain direct access storage
devices (DASDs) for computers. To make the technical improvements
demanded of the storage devices, such as faster access times and higher
recording densities, companies have been required to use magnetically
superior materials. These materials are extremely prone to corrosion
from water and are vulnerable to any contamination introduced in the
manufacturing process, such as organic or particulate matter.
Consequently, the storage device itself must be a miniature ``clean
room'' if it is to perform correctly. Manufacturers of some DASDs can
use water-based cleaners in much of the production process, but may
need to rely on the PFCs as water-displacement agents to achieve the
required high degree of cleanliness while protecting the water-
sensitive materials in the device.
As the acceptability determination states, before users adopt PFCs
as part of a substitute cleaning system, they must ascertain that
``other alternatives are not technically feasible due to performance or
safety requirements.'' This statement implies users will undertake a
thorough technical investigation of alternatives before implementing
the PFCs. A determination, for instance, that PFCs are necessary simply
``because my parts cannot tolerate water,'' is insufficient. Similarly,
companies should avoid rejecting an alternative simply because it is
flammable or toxic, since equipment now exists which may be feasible
for some uses that makes it possible for a broad spectrum of
alternatives to meet performance and safety standards.
Users may contact vendors of alternatives to explore with experts
on these alternatives whether or not they would work. This effort may
involve a detailed discussion of the type of parts, e.g., function,
substrate, geometry, and cleanliness standards. A possible approach is
to actually arrange for the parts to be tested with other cleaning
alternatives. For example, a concern regarding the flammability of
isopropyl alcohol is not sufficient reason to reject this alternative,
unless the user has contacted vendors and examined the newer styles of
equipment and found them insufficiently safe. To assist users in their
evaluation, EPA has prepared a list of vendors selling substitutes for
cleaning solvents. Although EPA does not require users to report their
test results in a certification to the Agency, companies must keep
these results on file for future reference.
In cases where users must rely on PFCs due to lack of other
options, they should make every effort to:
Adopt closed systems and recover, recycle and destroy
where possible.
Pre-clean where possible with other alternatives so as to
avoid unnecessary use of PFCs.
Reduce emissions to a minimum through equipment features
and conservation practices that address idling losses, liquid dragout,
and operator variables (adequate freeboard, chillers, welded piping,
programmable hoists, operator training, etc.).
Continue to search for long-term alternatives.
The Agency believes that it is reasonable to expect users to
achieve favorable CFC/PFC replacement ratios since PFCs have relatively
higher boiling points. In addition, the high price of PFCs makes
additional containment cost-effective. Companies forced to use PFCs due
to lack of other alternatives may use the PFC-based equipment to clean
and dry other precision parts, but only if the amount of PFCs needed to
stock the equipment does not increase.
Prospective users should also note that companies now investigating
PFC use contend that within 2-3 years, it will be possible to replace
the PFCs in cleaning equipment with HFCs or other options that have
zero ozone depletion potential and significantly lower global warming
potential. As a result, they view use of the PFCs as an important but
transitional solution to their cleaning needs. If PFCs are chosen, it
is important for users to begin working with chemical manufacturers to
start testing and qualifying these new materials to help speed
conversion when alternative chemicals become commercially available.
Users of PFCs should note that if other alternatives such as HFCs
or other cleaning substitutes are later found to meet performance or
safety standards, the Agency could be subject to a petition requesting
it to list PFCs as unacceptable substitutes due to availability of
other alternatives. If such claims are determined to be accurate and
EPA limits the acceptability listing even further, EPA may grandfather
existing uses but only to the extent warranted by cost and timing
considerations associated with testing and retrofitting.
(3) Precision cleaning. (a) Perfluorocarbons. Perfluorocarbons
(PFCs) are acceptable substitutes for CFC-113 and MCF in the precision
cleaning sector only for high-performance, precision-engineering
cleaning applications where reasonable efforts have been made to
ascertain that other alternatives are not technically feasible due to
performance or safety requirements. PFCs covered by this determination
are C5F12, C6F12, C6F14, C7F16, C8F18, C5F11NO, C6F13NO, C7F15NO, and
C8F16O. The electronics cleaning section discusses the justification
for this narrowed use acceptability listing.
Despite concerns about the global warming potential of PFCs, the
Agency has listed this narrowed application as an acceptable use of
perfluorocarbons in precision cleaning because, for certain high-
performance, precision-engineered components and equipment, a PFC-based
system may be the only viable alternative available to replace use of
class I or II compounds.
Types of precision components that may require PFC-based cleaning
include:
High-performance guidance, navigation and tracking systems
such as gyroscopes and accelerometers.
High-performance aerospace and avionics components and
equipment such as liquid oxygen systems or rotational hand controllers.
Critical analytical devices and their components used for
gas chromatography where low residue levels are essential.
Optical components made from plastics damaged irreparably
by water or other solvents or coated or mounted with specialized
materials.
Interested users should review the section on PFCs under
electronics cleaning for a full discussion of the considerations,
limitations, and requirements associated with selecting this
alternative.
d. Unacceptable substitutes. (1) Metals cleaning. (a) HCFC-141b and
its blends. HCFC-141b and its blends are unacceptable as substitutes
for CFC-113 and MCF in metals cleaning, with acceptability subject to
narrowed use limitations to be granted by EPA, if necessary, as CFC-113
replacements after the effective date of this listing. The effective
date for this listing is 30 days after the date of the final rule for
uses of HCFC-141b and its blends in new equipment (including retrofits
made after the effective date) and as of January 1, 1996, for uses of
HCFC-141b and its blends in existing equipment. For purposes of this
SNAP determination, ``existing equipment'' is defined to include
equipment that companies have shown a clear intention to use and have
purchased before the effective date of the SNAP determination, even if
that equipment has not yet been installed.
As discussed earlier in this action in Section VI.B., the Agency is
authorized to grandfather existing uses from a prohibition where
appropriate under the four-part test established in Sierra Club v. EPA,
supra. The Agency has conducted the four analyses required under this
test, and has concluded that the balance of equities favors a
grandfathering period of two years for uses of HCFC-141b in existing
equipment in this application. The prohibition set forth in this action
clearly represents a departure from previously established practice, as
use of the substitute was allowed previously. Existing users of HCFC-
141b who switched from class I substances into this solvent invested in
this substitute on the assumption that it would be a sufficient
improvement over the class I use. Prohibiting their use of the
substitute immediately would impose a severe economic burden on these
users. These factors taken together outweigh any statutory interest in
applying the new rule immediately to existing users. This is especially
true since the restriction applies immediately to new equipment using
HCFC-141b, which creates no incentive for continued investment in
equipment using HCFC-141b in this application.
The Agency's basis for proposing to restrict use of HCFC-141b is
that this compound has a comparatively high ODP--0.11. This is the
highest ODP of all the HCFCs; in fact, the ODP for HCFC-141b is nearly
equal to the ODP for MCF (0.12). For this reason, the Agency concludes
that replacing MCF with HCFC-141b is unacceptable, since using HCFC-
141b in place of MCF would not provide the environmental benefits that
the phase-out was designed to achieve.
To analyze the impacts from use of HCFC-141b as a CFC-113
replacement, the Agency estimated HCFC-141b use over time in each of
the cleaning end uses, and projected health effects due to ozone
depletion with the help of the Atmospheric Stabilization Framework
model. The modeling period starts in 1990 and measures health effects
expected for people born before 2030.
The findings of this modeling show adverse health effects of the
magnitude commonly associated with the use of ozone-depleting
compounds. For example, in the case of metals cleaning, the Agency
projected that use of HCFC-141b to replace MCF where technically
feasible could yield approximately 40,000 additional skin cancer cases
and approximately 1,000 additional skin cancer fatalities compared to
use of non-ozone-depleting substitutes.
The Agency believes that these figures and the availability of
superior substitutes as described in the section on acceptable
substitutes justify the proposal to list HCFC-141b as an unacceptable
substitute. The Agency believes that, in almost all applications, other
solvent cleaning substitutes are available that meet industry
performance and safety criteria. To reach its decision on HCFC-141b
use, the Agency also took into account the cost of other alternatives.
The analysis suggested that, although HCFC-141b can be used with
modification to existing equipment, the capital costs for the retrofit
and the materials costs in combination would be so high as to render
other alternatives comparatively affordable, even though they require
new equipment.
HCFC-141b will be restricted as a substitute only where other
alternatives exist to CFC-113 for the application in question. Several
companies have already contacted the Agency, indicating that they have
tested available alternatives to CFC-113, and that in some cases only
HCFC-141b meets performance or safety criteria. The most commonly cited
reasons for needing to use HCFC-141b are either applications where a
non-flammable solvent is required or where sensitive parts could be
destroyed by use of other cleaning systems.
For these applications of HCFC-141b, the Agency may find that the
uses are acceptable subject to limitations if it determines that these
critical uses persist beyond the grandfathering period provided in the
listing. For EPA to issue a narrowed use acceptability listing,
companies who believe they may need to use HCFC-141b past the effective
date must first contact EPA, since the Agency has not yet received any
indication from users of a technical need to use HCFC-141b past the
grandfathering period granted under the unacceptability listing.
Narrowed use acceptability listings are described in more detail in
section VII. of the Preamble. Companies interested in submitting a SNAP
application for a narrowed use are encouraged to contact the Agency at
least 90 days in advance of the expiration of the grandfathering
period. Companies that intend to use HCFC-141b within the parameters of
the final unacceptability listing and who will cease using HCFC-141b
after the expiration of the grandfathering period need not contact the
Agency.
The Agency believes that the decision to restrict HCFC-141b use as
a CFC-113/MCF substitute for metals cleaning will have little effect on
industry since few vendors of HCFC-141b have been selling HCFC-141b as
a metals cleaning substitute. Companies in this end use sector that
want to replace CFC-113 with HCFC-141b and use it beyond the date
described in this SNAP determination should review the section
referenced above. The Agency expects to receive few such requests,
however, since most metals cleaning is currently performed with MCF.
(2) Electronics cleaning. (a) HCFC-141b and its blends. HCFC-141b
and its blends are unacceptable as substitutes for CFC-113 and MCF in
electronics cleaning, with acceptability subject to narrowed use
limitations to be granted by EPA, if necessary, as CFC-113 replacements
after the effective date of this listing. The effective date for this
prohibition is 30 days after the date of the final rule for new
equipment (including retrofits made after the effective date) and
January 1, 1996 for existing equipment. The structure and reasons for
this unacceptability listing are the same as those for the decision on
HCFC-141b as a metals cleaning substitute. As in the metals cleaning
sector, the Agency will grant narrowed use acceptability listings in
limited cases for use beyond the grandfathering period of the listing,
as necessary. As discussed earlier in this action in section VI.B., the
Agency is authorized to grandfather existing uses from a prohibition
where appropriate under the four-part test established in Sierra Club
v. EPA, supra.
The Agency has conducted the four analyses required under this
test, and it has concluded that the balance of equities favors a
grandfathering period of two years for existing equipment in this
application. The prohibition set forth in this action clearly
represents a departure from previously established practice, as use of
the substitute was allowed previously. Existing users of HCFC-141b who
switched from class I substances into this solvent invested in this
substitute on the assumption that it would be considered an acceptable
substitute. It would impose a severe economic burden on these users to
prohibit their use of the substitute immediately, with no provision of
time to allow them to recover their investment in existing equipment or
acquire new equipment in a timely fashion. These factors taken together
appear to outweigh any statutory interest in applying the new rule
immediately to existing users, especially since the restriction would
apply immediately to new equipment using HCFC-141b, which would serve
to prevent further ozone depletion from use of HCFC-141b in this
application.
As with metals cleaning applications for HCFC-141b, the Agency
modeled potential HCFC-141b use in electronics cleaning applications
over time, and projected health effects due to ozone depletion with the
help of the Atmospheric Stabilization Framework model. For electronics
cleaning, the maximum market penetration for HCFC-141b as a replacement
for CFC-113 is 90 percent. With this penetration, the model predicted
approximately 400 additional skin cancer fatalities and 30,000
additional skin cancer cases compared to uses of non-ozone-depleting
substitutes.
(3) Precision cleaning. (a) HCFC-141b. HCFC-141b and its blends are
unacceptable as substitutes for CFC-113 and MCF in precision cleaning,
with acceptability subject to narrowed use limitations to be granted by
EPA, if necessary, as CFC-113 replacements after the effective date of
this listing. The effective date for this listing is 30 days after the
date of the final rule for new equipment and as of January 1, 1996, for
existing equipment. The structure and reasons for this decision are
described in the section on metals cleaning. As discussed earlier in
this action in section VI.B., the Agency is authorized to grandfather
existing uses from a prohibition where appropriate under the four-part
test established in Sierra Club v. EPA, supra.
The Agency has conducted the four analyses required under this
test, and it has concluded that the balance of equities favors a
grandfathering period of two years for existing equipment in this
application. The prohibition set forth in this action clearly
represents a departure from previously established practice, as use of
the substitute was allowed previously. Existing users of HCFC-141b who
switched from class I substances into this solvent invested in this
substitute on the assumption that it would be considered an acceptable
substitute. It would impose a severe economic burden on these users to
prohibit their use of the substitute immediately, with no provision of
time to allow them to recover their investment in existing equipment or
acquire new equipment in a timely fashion. These factors taken together
outweigh any statutory interest in applying the new rule immediately to
existing users, especially since the restriction would apply
immediately to new equipment using HCFC-141b, which would serve to
prevent further ozone depletion from use of HCFC-141b in this
application.
In the case of precision cleaning uses of HCFC-141b, the Agency's
modeling of HCFC-141b use as a CFC-113 replacement projected
approximately 5,000 additional skin cancer cases when compared to use
of non-ozone-depleting substitutes.
As in the case of other cleaning applications, the Agency finds
unacceptable substitutions of HCFC-141b to replace MCF, since these
compounds have nearly identical ODPs. Here again, the Agency will
grant, if necessary, a limited narrowed use acceptability listings for
CFC-113 past the exemption granted in the grandfathering period.
However, the Agency expects only few requests for permission to use
HCFC-141b to come from this sector, since most companies who requested
exemptions to date to have stated that they view their use of HCFC-141b
only as an interim solution. EPA believes that, absent future
indications from such companies, all uses of HCFC-141b can be
terminated by the effective date of the unacceptability listing.
G. Fire Suppression and Explosion Protection
1. Overview
Halons are gaseous or easily vaporizable halocarbons used primarily
for putting out fires, but also for explosion protection. The two
halons used most widely in the United States are Halon 1211
(chlorodifluorobromomethane) and Halon 1301 (trifluorobromomethane).
Halon 1211 is used primarily in streaming applications and Halon 1301
is typically used in total flooding applications. Some limited use of
Halon 2402 also exists in the United States, but only as an
extinguishant in engine nacelles (the streamlined enclosure surrounding
the engine) on older aircraft and in the guidance system of Minuteman
missiles.
Halons are used in a wide range of fire protection applications
because they combine five characteristics. First, they are highly
effective against solid, liquid/gaseous, and electrical fires (referred
to as Class A, B, and C fires, respectively). Second, they are clean
agents; that is, they dissipate rapidly, leaving no residue and thereby
avoiding secondary damage to the property they are protecting. Third,
halons do not conduct electricity and can be used in areas containing
live electrical equipment. Fourth, halons are gaseous substances that
can penetrate in and around physical objects to extinguish fires in
otherwise inaccessible areas. Finally, halons are generally safe for
limited human exposure when used with proper exposure controls.
Despite these advantages, halons are among the most ozone-depleting
chemicals in use today. Halon 1301 has an estimated ODP of 10; Halon
1211 has an estimated ODP of 3. Thus, while total halon production
(measured in metric tons) comprised just 2 percent of the total
production of class I substances in 1986, halons represented 23 percent
of the total estimated ozone depletion potential of CFCs and halons
combined.
The greatest releases of halon into the atmosphere occur not in
extinguishing fires, but during testing and training, service and
repair, and accidental discharges. Data generated as part of the
Montreal Protocol's technology assessment indicate that only 15 percent
of annual Halon 1211 emissions and 18 percent of Halon 1301 emissions
occur as a result of use to extinguish actual fires. These figures
indicate that significant gains can be made in protecting the ozone
layer by revising testing and training procedures and by limiting
unnecessary discharges through better detection and dispensing systems
for halon and halon alternatives.
Additional information on specific halon uses can be found in the
Montreal Protocol 1991 Assessment or in other background material in
the public docket. The determinations found in this section are based
on the risk screen described in the background document entitled ``Risk
Screen on the Use of Substitutes for Class I Ozone-Depleting
Substances: Fire Extinguishing and Explosion Protection (Halon
Substitutes)'', and in supplementary assessments included in the public
docket.
2. Substitutes for Halons
The fire protection community has made considerable progress in
identifying and developing substitutes for halons in fire protection
applications. Several manufacturers have submitted information
regarding substitute streaming and total flooding agents, and the
National Fire Protection Association (NFPA) has initiated efforts to
develop standards for their use in total flooding scenarios (NFPA
2001). In addition, manufacturers are seeking Underwriters Laboratories
(UL) and Factory Mutual Research Corporation (FMRC) certification for
systems employing the new agents. The Agency's review of halon
substitutes is intended not to replace, but to complement the guidance
of the fire protection community in directing the transition away from
halons to substitutes posing lower overall risk.
Many recent efforts to develop substitutes for halon have focused
on halocarbon chemicals. These are considered potential
``replacements'' for halon because they possess halon-like properties
(gaseous, non-conducting) and because they can be used on Class A, B,
and C fires. Some of the replacement chemicals are chemical action
agents which, like halons, suppress fires by interfering with the free
radical chain reactions that sustain a fire. Others are physical action
agents which cool, dilute, or smother the fire (separating the air and
fuel). In general, chemical action agents are much more effective fire
suppressants than physical action agents.
Halocarbons represent only a portion of agents available for fire
protection, and in fact appear to be a decreasing portion as users more
and more are choosing to install ``alternative'' systems. Water, carbon
dioxide, foam, and dry chemical are already in widespread use as fire
extinguishants and may capture some of the former halon market. Water
mist, powdered aerosols and inert gases are new technologies that are
also likely to claim part of the former halon market. EPA encourages
users to assess their risk management schemes and, where possible, to
minimize reliance on chemical agents. Nonchemical alternatives should
be seriously evaluated to determine whether they afford the necessary
level of protection in any given application.
In assessing toxicity of a halocarbon, EPA pays special attention
to consumer and worker exposure to discharges during fire emergencies
and accidental discharges. In these acute, episodic exposures to the
halon substitutes, cardiac sensitization is of particular interest. The
term cardiac sensitization refers to an increased susceptibility of the
heart to adrenaline (or other catecholamines) which may result in
potentially fatal heart arrhythmias.
Several studies involving human exposure in a laboratory setting
establish the potential significance for human health of animal data on
cardiac sensitization. Evaluating the safety of potential halon
substitutes requires the measurement of the No Observed Adverse Effect
Level (NOAEL) and the Lowest Observed Adverse Effect Level (LOAEL) of
cardiac sensitization in an appropriate species, usually the dog. EPA
uses the NOAEL value as the basis to ensure protection of the worker
population. The protocols used to determine the cardiotoxic NOAEL and
LOAEL concentrations for each agent are conservative. The
cardiotoxicity effect levels are measured in animals that have been
made more sensitive to these effects by the administration of
epinephrine concentrations which are just below the concentrations at
which epinephrine alone causes cardiotoxicity. The concentration of
epinephrine required to cause this heightened sensitivity is
approximately ten times greater than the concentration a human being
would be likely to secrete under stress.
The determination of the safety of either a flooding or streaming
agent substitute is also dependent on a number of other related
factors. For total flood systems, the magnitude of exposure will depend
on the design concentration of the flooding agent (as determined by the
substitute's extinguishing concentration plus 20 percent, as specified
by NFPA guidelines) and the length of time it takes a person to
evacuate the area in which the agent is released. In assessing exposure
and consequent use conditions, the design concentration of a total
flood substitute is compared to its cardiotoxic NOAEL and LOAEL levels.
Generally, if the design concentration is higher than the agent's LOAEL
level, then the agent is not suitable for use in normally occupied
areas. EPA is adopting the OSHA standard (29 CFR 1910, subpart L)
section 1910.162, which limits the exposure to an agent based upon the
length of time it takes to evacuate an area. In addition, EPA makes
note that OSHA standard 1910.160 also applies to gaseous total flood
systems.
In addition, EPA recognizes that agents should not be used at a
concentration that significantly displaces oxygen in the lungs. Most of
the CFC and halon substitutes are gaseous, heavier-than-air compounds,
which following a leak or catastrophic emission may tend to pool near
the ground, i.e. in the breathing zone. Since these agents are, in the
main, colorless with minimal odor and little toxicity or irritant
effect, they can lead to asphyxiation by oxygen displacement if the
unwary inadvertently walk into an area of oxygen depletion. The
designer of a total flood system should be particularly alert to this
possibility during discharge and subsequent dispersion of the agent in
the space. For compounds which do not elicit a cardiotoxic effect until
very high concentrations have been reached, care should be taken that
sufficient oxygen remains in the room so that asphyxiation will not
occur.
In contrast to total flooding agents, exposure to substitute
streaming agents can be expected to vary greatly depending on the
amount of agent released, the time needed to extinguish a fire, the
size of the room or enclosure in which a fire occurs, the size of the
fire, the proximity of the person to the point of discharge of the
agent, the rate at which fresh air infiltrates the space, and the air
exchange rate near the fire. Assessment of exposure in streaming
applications is much more complicated. EPA employs the `box model' to
assess consumer exposure, which has been widely used for many years to
estimate probable exposures of workers to hazardous airborne materials,
and has been described in detail by the National Institute for
Occupational Safety and Health (NIOSH) and is discussed in detail in
the background documents. The box model takes into consideration
assumptions on volume of the space in which the extinguishant is used,
rate at which fresh air infiltrates the space, amount and rate of agent
release, area of the fire, location of the worker, and the air exchange
rate in the vicinity of the fire. Values obtained through the box
model, compared to cardiotoxic NOAEL/LOAEL values, provide a screen for
assessing risk. However, EPA has found that the model often overstates
the actual exposure to an agent, and therefore, EPA requires personal
monitoring tests be conducted in actual use scenarios in order to
complete the assessment.
Evaluating halon substitutes also requires assessing the efficacy
of substitute agents. The efficacy of a fire protection agent can be
compared using a cup burner or full scale test to obtain the
extinguishing concentration in a particular fuel. NFPA standards
require an additional 20 percent be added to obtain the design
concentration. Most values identified in this rule are obtained by cup
burner, while some are obtained by full scale testing, and most are in
heptane. This measure is included in the discussion of halon
substitutes for information and comparative purposes, and EPA does not
assert that the efficacy values listed here are appropriate for all
fire or explosion hazards. The user community is cautioned to consult
the appropriate NFPA standard, relevant OSHA regulations, and
professional fire consultants to determine actual requirements.
After concluding the analysis of halon alternatives, EPA in some
cases finds acceptable the use of an agent only under certain
conditions. In implementing its use of conditions, the Agency has
sought to avoid overlap with other existing regulatory authorities. EPA
believes that section 612 clearly authorizes imposition of use
conditions to ensure safe use of replacement agents. EPA's mandate is
to list agents that ``reduce the overall risk to human health and the
environment'' for ``specific uses.'' In light of this authorization,
EPA is only intending to set conditions for the safe use of halon
substitutes in the workplace until OSHA incorporates specific language
addressing gaseous agents into OSHA regulation. Under OSHA Public Law
91-596, section 4(b)(1), OSHA is precluded from regulating an area
currently being regulated by another federal agency. EPA is
specifically deferring to OSHA, and has no intention to assume
responsibility for regulating workplace safety especially with respect
to fire protection. EPA's workplace use conditions will not bar OSHA
from regulating under its Public Law 91-596 authority. The substitutes
for halons in fire protection applications are discussed in the next
section by class of chemical.
a. Brominated hydrofluorocarbons. Brominated hydrofluorocarbons
(HBFCs) are effective halon substitutes. Because these substances
contain bromine, they act as chemical action agents in the same manner
as the halons. In fact, some HBFCs are more effective than Halons 1211
and 1301 in specific applications. For this reason, HBFCs can replace
Halons 1211 and 1301 on nearly a one-to-one basis and appear to have
significant applicability in existing systems. However, the presence of
bromine also means that these agents have higher ozone-depleting
potentials than other halon substitutes.
At this time, only one HBFC, HBFC-22B1, is expected to be
commercially available in the near term. HBFC-22B1 can, however, serve
only as an interim substitute for halons. The substance has an ODP of
0.74 and has been listed as a class I substances. Under the Montreal
Protocol and the Clean Air Act, production of HBFC-22B1 is required to
end January 1, 1996.
b. Hydrochlorofluorocarbons. A number of hydrochlorofluorocarbons
(HCFCs) have also been suggested as halon replacements. These include
HCFC-22, HCFC-123, and HCFC-124. These HCFCs will extinguish fires but
because they are physical action agents, they are considerably less
effective than halons or HBFCs. Thus, high concentrations must be
achieved to extinguish fires. Further, although the ozone depletion
potential of HCFCs is considerably lower than that of either halons or
HBFCs, they are listed as class II chemicals under the Clean Air Act.
The production of HCFC-141b will be phased out beginning January 1,
2003; HCFC-22 and HCFC-142b beginning January 1, 2020; and all other
HCFCs beginning January 1, 2030 (58 FR 65018, December 10, 1993).
In addition, under section 610(d) of the CAA as amended, HCFCs in
pressurized dispensers are banned from sale or distribution after
January 1, 1994. Under the final rulemaking for section 610 (58 FR
69637, December 30, 1993) EPA interpreted section 610(d) to exclude
HCFCs which are part of an installed `system.' The final rule exempts
total flooding systems and those streaming applications which
incorporate fixed, automatic systems. However, section 610(d) only
allows the sale of an HCFC in a portable fire extinguisher where other
unregulated agents are not suitable for the intended applications.
Because alternatives are available for residential uses, EPA intends to
publish a proposed rulemaking under section 612 to update the SNAP list
of acceptable substitutes and to ban the sale and use of HCFCs in
portable fire extinguishers for residential applications. However, in
commercial (including industrial and military) settings, the variety of
hazards are too broad to create standards through rulemaking, and
therefore under section 610(d) EPA has established industry-based
mechanisms for controlling the sale of HCFCs.
Generally, while HCFCs can serve only as interim halon substitutes
due to their scheduled phaseout as class II substances, EPA believes
that they serve an important transitional role in the phaseout of class
I substances. HCFC-22 has been suggested as a total flooding agent, but
this compound is unlikely to be used as a single agent in normally
occupied areas due to its cardiotoxic profile.
HCFC-123 is being proposed as a streaming agent to replace Halon
1211, both in pure form and in blends. HCFC-123 could replace Halon
1211 at a ratio of 1.8 by weight--a ratio considerably better than that
of most other streaming substitutes. HCFC-123 has the lowest ODP of all
the HCFCs proposed as halon substitutes, and its global warming
potential (GWP) is half that of other HCFC substitutes.
HCFC-124 is being proposed as both a total flooding agent and a
streaming agent, both alone and in blends. HCFC-124 has relatively low
ODP and GWP values. Animal testing indicates that the substance may be
lethal to rats at a level greater than 23 percent over a four hour
period. Due to its cardiotoxic profile, this agent is not suitable for
use in total flooding applications in normally occupied areas. However,
pending personal monitoring tests to assess actual exposure, it is
possible that this agent could be used as a streaming agent.
c. Hydrofluorocarbons. Hydrofluorocarbons (HFCs) have also been
suggested as halon substitutes. HFCs are physical action agents and are
less effective than halons or HBFCs. Due to their reduced efficacy,
larger storage volumes are required for use in fire protection systems.
Their great advantage over halons, HBFCs, and HCFCs is that HFCs have
an ozone depletion potential of zero. However, when exposed to fires,
HFCs potentially decompose into greater amounts of hydrogen fluoride
(HF) than do HCFCs, depending on the number of fluorines in the
molecule. Discharge of these chemicals onto a fire must be rapid or
early to prevent the buildup of large amounts of these decomposition
products.
In addition, HFCs can potentially contribute to global climate
change. Because of this potential, HFCs are included in President
Clinton's Climate Change Action Plan (CCAP). Under this plan, EPA is
directed to limit uses of greenhouse gases as substitutes for ozone-
depleting compounds. Because EPA is simultaneously also interested in
promoting the broader shift away from ozone-depleting compounds, any
limits on use will be imposed wherever possible in ways that preserve
as much flexibility for those trying to move to alternatives as
possible. To minimize unnecessary emissions of greenhouse gases, EPA is
recommending that users limit testing only to that which is essential
to meet safety or performance requirements; recover HFCs from the fire
protection system in conjunction with testing or servicing; and recycle
recovered agent for later use or destruction. Manufacturers of these
agents must recognize their responsibility to prevent unnecessary
emissions of these gases. Product stewardship programs may be a useful
mechanism to help users meet these requirements. EPA will reexamine how
to control unnecessary emissions of greenhouse gases in the future.
HFC-23, HFC-32, HFC-125, HFC-134a, and HFC-227ea have all been
proposed as total flooding agents. HFC-134a and HFC-227ea have also
been proposed as streaming agents. HFCs tend to possess less risk of
acute cardiotoxicity than do the HCFCs or HBFC-22B1.
HFC-32 has been determined to be flammable, with a large
flammability range, and is therefore inappropriate as a halon
substitute. In the next SNAP update, EPA intends to propose listing
this agent as unacceptable in total flood applications.
d. Perfluorocarbons. Perfluorocarbons (PFCs) are fully fluorinated
compounds which do not contribute to ozone depletion. In addition, PFCs
are nonflammable, essentially non-toxic, and are not VOCs. PFCs are
effective fire protection agents, having the lowest required
extinguishing concentration of any of the suggested substitutes other
than HBFCs. However, these compounds have high molecular weights, which
create weight and storage replacement ratios that are somewhat higher
than the HCFCs and many of the HFC candidates. Two PFCs have been
submitted as halon replacements: Perfluorobutane (C4F10) as a
total flood replacement for Halon 1301, and perfluorohexane
(C6F14) as a substitute for Halon 1211. In the NPRM, these
agents were referred to as FC 3-1-10 and FC 5-1-14, respectively.
The principal environmental characteristic of concern for PFCs is
that they have long atmospheric lifetimes and have the potential to
contribute to global climate change. PFCs are also included in the CCAP
which broadly instructs EPA to use section 612, as well as voluntary
programs, to control emissions.
While PFCs are extremely persistent, their favorable toxicity
profile makes these agents attractive for use in occupied areas. Thus,
EPA believes that there are instances in which PFCs represent the only
viable alternative to transition away from the CFCs or halons.
The Agency is finding use of PFCs acceptable only for applications
where reasonable efforts have been made to determine that no other
alternatives are technically feasible due to performance or safety
requirements. However, as with all of the substitutes which are
greenhouse gases and ozone-depleting substances, EPA recommends that
users limit testing only to that which is essential to meet safety or
performance requirements; recover agent from the fire protection system
in conjunction with testing or servicing; and recycle or destroy agent
that is recovered from a system. In addition, EPA encourages
manufacturers to develop aggressive product stewardship programs to
help users avoid such unnecessary emissions. EPA will reexamine how to
control unnecessary emissions of greenhouse gases in the future.
e. Chlorofluorocarbons. Chlorofluorocarbons (CFCs) have also been
proposed as halon alternatives, either individually or in blends. These
compounds are also class I substances, however, and as a matter of
policy EPA will not encourage shifting from one class I substance to
another, despite the fact that the ODPs of the CFCs are significantly
lower than those of Halons 1211 and 1301. EPA does not believe it is
appropriate to encourage shifting to substitutes that are required to
be phased out in the near term. In addition, the sale and distribution
of CFCs in pressurized dispensers (in this sector, portable fire
extinguishers) are controlled under section 610(b) of the CAA.
f. Blends. A number of manufacturers have proposed proprietary
blends of chemicals for fire protection applications. These blends
combine a variety of CFCs, HCFCs, HFCs, PFCs, inert gases, and other
additives to achieve desired levels of effectiveness, toxicity, and
decomposition products. Most of these blends contain constituents that
have non-zero ODPs and GWPs. In assessing the ODP and GWP of such
blends, the Agency has examined both the weighted average of the
constituents and the individual characteristics of the constituents.
Because toxicity varies with the exact composition of the blend, EPA
requires cardiotoxicity tests to be conducted on the blend itself,
rather than being inferred from the constituents.
g. Non-halocarbon alternative agents. Non-halocarbon alternative
agents such as CO2, dry chemical, foams, and water that are
currently in widespread use and that are covered in NFPA standards and
OSHA regulations may also be used as substitutes for halon. These
agents are not as widely applicable as the halocarbon substitutes, and
must be used where recommended by the manufacturers and approved by
standard-setting entities such as the NFPA.
In addition, several manufacturers have developed new technologies
to adapt traditional agents to the halon market. Two manufacturers have
developed inert gas blends as Halon 1301 substitutes in total flood
systems. One of them, containing CO2 mixed with inert gases has
already been included in the new NFPA 2001 standard.
Water sprinkler systems are capturing part of the halon substitute
market, often in conjunction with improved detection systems and risk
management programs which isolate the degree of liability in a given
fire event. A promising new water technology incorporates fine water
droplets to create a water mist or fog. It has been suggested that
water mist systems are safe for use on Class A and B fires, and even
can be used on Class C electrical fires without causing secondary
damage. Because the environmental, health and safety issues of the
various types of water mist systems have not yet been fully addressed,
EPA is listing water mist as pending in this rule, and will work with
NFPA, manufacturers, and others in order to include it in the next SNAP
update.
Again, while dry chemicals are in widespread use, another new
technology for both the total flooding and streaming markets involves
the use of powdered aerosols, which combine fine powder particulates
with gas to achieve a total flood effect.
While foams are also in widespread use, one manufacturer has
prepared a blend of etoxylated linear alcohol and sulfonated soap for
use in streaming applications. This blend is not a clean agent, but
offers another alternative technology where secondary damage can be
tolerated. It presents benefits of rapid cool-down, prevention of
reignition, and decrease in the quantity of water required to
extinguish fires.
3. Response to Comments
Key issues included in the public comment are addressed in this
section. For a complete discussion of public comments received, refer
to the ``Response to Comments'' document in the public docket. The
issues addressed in this section include: Alternative technologies,
efficacy and design, use conditions, narrowed use restrictions, and
halon categories and subdivisions.
a. Alternative technologies. As halon is being phased out, there is
a growing interest in not only clean chemical substitutes but also in
reassessing the use of conventional substitutes, adopting new risk
management strategies and using alternative technologies. Several
commenters expressed the view that alternatives such as water and
CO2 are not clean agent chemical substitutes, but rather
conventional suppression system substitutes, and have been in
widespread use for many years. Thus, these commenters stated that such
alternatives are outside the scope of SNAP and that EPA should only
list clean agent chemical substitutes. They indicated that it would be
counterproductive to list all acceptable substitutes and alternatives
under SNAP, which are better addressed by the entire fire protection
community, and that doing so would restrict trade and development of
new technology. One commenter said it was unclear what purpose would be
served by attempting to list all substitutes and alternatives,
including a variety of system technologies.
Section 612 of the Clean Air Act specifies that class I and class
II substances shall be replaced by ``chemicals, product substitutes, or
alternative manufacturing processes that reduce overall risks to human
health and the environment'' and directs EPA to assist in identifying
such substitutes and alternatives, promote their development, maintain
a public clearinghouse, and publish lists of acceptable and
unacceptable substitutes for specific uses. EPA interprets this
language as a broad mandate to include alternative technologies. For
the fire suppression and explosion protection sector, EPA is defining
alternative technology to be any non-halocarbon substance discharged
for the purpose of fire suppression or explosion protection. Thus,
water mist, inert gas mixtures, powdered aerosols and any other `not in
kind' alternative to CFCs and halons are alternative technologies. EPA
believes that its assessment of potential human health and
environmental impacts of these new technologies does, in fact, speed
their acceptance and adoption by removing uncertainty about their safe
use. In addition, while water sprinklers, carbon dioxide, foam, and dry
chemical are currently in use, these substances fall within the
definition of alternative technology. EPA will simply list these as
acceptable and note their applicable NFPA standards.
EPA will assess each class of alternative technology and determine
whether a separate review is prudent due to variations in formulation
and design of similar technologies, or whether it is possible to
construct a broad listing of acceptability that covers several
manufacturers. In this final rule, EPA is listing each water mist
technology as well as inert gas blends and powdered aerosols separately
due to the unique formulation, design and intended use of each. An
acceptable or unacceptable listing of a particular alternative
technology is not generalizable to similar technologies from other
manufacturers.
b. Efficacy and design issues. Many commenters state that in the
NPRM, EPA has assumed that a single design concentration (obtained from
a cup burner test for heptane) is applicable for all fire hazards and
requested that EPA remove all reference to design concentration.
However, several commenters noted that listing of the design
concentration was useful in comparing the relative efficacy of
substitute agents, as long as EPA is clear about the source of the
data.
In addition, many commenters feel that while EPA states that the
SNAP rule ``is intended not to replace, but to complement the guidance
of the fire protection community,'' EPA has ``dangerously
oversimplified'' the many factors that must be taken into consideration
in designing a system, and a listing of ``acceptability'' implies that
any alternative will work in a safe and effective manner. One commenter
specifically requested that EPA remove all references to design and
installation requirements.
Many commenters believe that EPA should not comment on the efficacy
of substitutes, as this is outside the scope of the SNAP rule, and that
EPA should only comment on environmental and toxicological concerns.
The commenters believe EPA should only list the agent name, EPA's
decision, NOAEL, and any specific environmental or regulatory concerns
(such as ODP, GWP, or future phaseout date.) One commenter is concerned
that EPA's involvement in efficacy issues will cause users to select
agents that will result in less effective and more expensive protection
than is needed, and will make American industry less competitive in
world markets.
One commenter summed up the requests of many others, suggesting
that, at a minimum, EPA should include cautionary wording that a
listing of `acceptable' does not imply the agent will work in any given
application. Further, EPA should point out that the efficacy of an
agent is dependent on the application system and should encourage users
to consult current consensus fire codes and standards such as those
developed by NFPA.
By contrast, EPA believes that efficacy of a substitute agent must
be a consideration in decision making, because EPA's charge is to
ensure that substitutes are not on balance more risky than the ozone-
depleting compounds being replaced. A substitute which is not effective
cannot be considered safer than the halon being replaced. In addition,
design concentration is germane to a discussion of potential exposure
and its consequent effects on human health.
In addition, while most agents submitted under SNAP are relatively
effective, the analysis of efficacy assists in the assessment of the
availability of substitutes in various niche markets. EPA intends to
accept as many viable substitutes as possible. If, due to technical
concerns such as weight or storage volume equivalency, there are few or
no substitutes available in a given application, EPA must ensure that
it does not restrict the few available choices based on other issues,
such as environmental concerns. EPA's primary task in SNAP is to
facilitate the move away from ozone-depleting compounds, and this goal
cannot be served in the fire extinguishing sector without a full
understanding of the characteristics of the available substitutes.
However, the Agency agrees with the commenters that data sources
should be clearly identified. EPA does not intend to imply that cup
burner data for heptane dictates the proper design concentration for
all applications and for all fire hazards, nor does EPA intend to imply
that a listing of `acceptable' means that an agent may be used in any
application without professional consultation. In this final rule, EPA
reaffirms the need for all potential users to consult NFPA technical
standards, OSHA regulations, and fire protection professionals for
actual design considerations.
c. Use conditions. In response to EPA's request for comment on
whether section 612 authorizes the agency to set use conditions,
several commenters argued that setting use conditions is not within the
purview of section 612. Some commenters stated that EPA has exceeded
its scope of authority under the Clean Air Act, and that EPA should
defer regulation of workplace safety to OSHA, which is the appropriate
entity. Other commenters stated that EPA failed to consult with OSHA
and thus overstepped its authority by setting workplace conditions.
Other commenters feel it is proper for EPA to establish exposure
limits on new agents as it will ensure public safety until OSHA
regulations are complete, especially where there is little historical
exposure information to rely on.
EPA believes that section 612 clearly authorizes imposition of use
conditions to ensure safe use of replacement agents. EPA's mandate is
to list agents that ``reduce the overall risk to human health and the
environment'' for ``specific uses.'' Where use of a substitute without
conditions would increase overall risk, EPA is authorized to find the
use of such substitutes totally unacceptable. Included in this is the
authority to find acceptable the use of the substitute only if used in
a manner that reduces overall risk, and to find unacceptable its use in
all other cases.
Further, EPA's use conditions on workplace safety for halon
substitutes will exist only in the interim, until OSHA incorporates
specific language addressing gaseous agents in the OSHA law. Under OSHA
Public Law 91-596, section 4(b)(1), OSHA is precluded from regulating
an area currently being regulated by other federal agencies. EPA is
specifically deferring to OSHA, and has no intention to assume
responsibility for regulating workplace safety in regard to fire
protection. Consequently, EPA's use conditions are effective only until
OSHA acts and will terminate by their own terms once OSHA establishes
standards.
OSHA Sec. 1910.162 governs the use of all gaseous agents in fixed
extinguishing systems, however EPA finds that the guidance is not
sufficiently explicit on the allowable concentrations of the different
agents. While paragraph 1910.162(b)(3) stipulates that ``[t]he employer
shall assure that employees are not exposed to toxic levels of gaseous
agent or its decomposition products,'' it does not define what a `toxic
level' is. In examining paragraph 1910.162 (b)(6)(i) through
(b)(6)(iii), EPA concludes that it is OSHA's intent to limit exposure
to gaseous agents based upon cardiotoxicity levels. EPA's conclusion
was confirmed in discussions with OSHA. EPA therefore concludes that it
is appropriate under the SNAP program to stipulate what the cardiotoxic
levels for each agent are, and, until OSHA incorporates clarifying
language, to impose use conditions that apply OSHA standard 1910.162 in
its entirety to these agents.
References in Sec. 1910.162 to a Halon 1301 concentration of 7%
imply a cardiotoxic NOAEL, and references to a Halon 1301 concentration
of 10% imply a cardiotoxic LOAEL. In this regulation, EPA is clarifying
the intent of Sec. 1910.162(b)(3) to allow the use of the substitute
gaseous agents only according to paragraph (b)(6)(i) through
(b)(6)(iii), using the cardiotoxic NOAEL and LOAEL of each agent as the
concentration referenced in each subparagraph. Thus, until OSHA
establishes applicable work-place requirements, the use conditions in
this final rule on halocarbon substitutes, using the OSHA regulation as
a standard, will be as follows:
Where egress from an area cannot be accomplished within
one minute, the employer shall not use this agent in concentrations
exceeding its NOAEL.
Where egress takes longer than 30 seconds but less than
one minute, the employer shall not use the agent in a concentration
greater than its LOAEL.
Agent concentrations greater than the LOAEL are only
permitted in areas not normally occupied by employees provided that any
employee in the area can escape within 30 seconds. The employer shall
assure that no unprotected employees enter the area during agent
discharge.
These conditions will no longer apply once OSHA establishes
applicable workplace requirements.
EPA will adopt the commenters' suggestion that the use conditions
be stated once in the beginning of each section and will not repeat
them for each agent.
d. Narrowed use restrictions. Many commenters requested that EPA
remove the narrowed use restrictions placed upon HFC-23,
C4F10, and C6F14. These commenters argue that
narrowed use restrictions are unnecessary, because the fire protection
community (including entities such as NFPA, UL, FMRC and others) has
successfully regulated fire protection historically and remains better
able to determine which agents should be selected based on design and
use criteria, including environmental and toxicological acceptability,
efficacy, cost, engineering practice and specific risk.
It is not the intent of EPA to interfere with the ability of the
fire protection community to use its expertise in selecting agents and
designing appropriate and cost-effective systems based upon technical
criteria. EPA congratulates the industry on its excellent record of
self-regulation, and seeks to work cooperatively with the regulated
community in our efforts to address the phaseout of halon. However, use
of fire protection agents is, in fact, already regulated under federal
law, i.e. OSHA, to ensure their safe use.
Under the Clean Air Act, EPA is mandated to evaluate substitutes to
reduce ``overall risk to human health and the environment'' and to
publish lists of acceptable and unacceptable substitutes ``for specific
uses.'' EPA interprets section 612 as giving the Agency authority to
limit use where there are concerns due to health or environmental
factors. Because a primary goal of the SNAP program as a whole is to
speed the market's transition away from ozone-depleting substances,
conditional acceptances were accorded to many substitutes which might
be unacceptable in the absence of any use conditions. EPA believes
that, through the setting of narrowed use restrictions in the limited
cases where they are warranted, it has actually expanded the list of
available options for fire protection experts to choose from.
Many commenters stated that the narrowed use restrictions as
written in the NPRM by EPA are vague and confusing, and overly complex,
leading to uncertainty. Commenters asked that EPA clarify such vague
terms as ``high value,'' ``public safety,'' ``national security,''
``life support,'' and ``critical.'' They state that ambiguity will
cause many users to be reluctant to use the new substitute agents.
Concern was expressed that the fire protection community will have to
spend an inordinate amount of time interpreting and deciphering whether
a particular system meets EPA's requirements. Some commenters advised
that, if EPA retains narrowed use restrictions, these restrictions
should be better defined through work with the fire protection
industry. One commenter suggested that a more easily enforced method
would be to allow use only in applications where toxicity of other
substitutes would not be acceptable. Furthermore, some commenters noted
that EPA's publicly expressed concern about the environmental
acceptability, particularly the global warming impacts, of certain
agents has already slowed interest in the development of systems. They
state that as a result, there is continued dependence on halon for
certain critical applications where no other alternative agent is
suitable, such as in explosion inerting applications.
EPA agrees with the commenters that narrowed use restrictions must
not contribute to uncertainty and a consequent reluctance to move away
from ozone-depleting fire fighting agents. To address this concern, EPA
has worked with agent manufacturers, system designers, and members of
the regulated community to better clarify the intent and the wording of
narrowed use restrictions. In this final rule, EPA is amending the
means of controlling unwanted emissions of long-lived agents. In the
NPRM, EPA attempted to narrow the scope of uses for the PFCs
(C4F10 and C6F14) and for HFC-23 by listing the use
categories that were acceptable. Because the regulated community found
this listing ambiguous, and because EPA could not list all possible
uses that would require this agent, EPA explored the technical criteria
that would define where this agent was best applied, as one commenter
suggested. This approach was appealing, but, again, tended to place the
task of system design upon the Agency. Therefore, for the PFCs, the
Agency has decided to adopt an approach that places the burden of proof
upon the end-user for determining that no other alternative was
technically feasible for that application.
Users shall self-certify the need to use restricted agents. Before
users adopt C4F10 or C6F14, both restricted agents,
they must make reasonable efforts to ascertain that ``other substitutes
or alternatives are not technically feasible due to performance or
safety requirements.'' Users are expected to evaluate the technical
feasibility of other substitutes or alternatives to determine their
adequacy to control the particular fire or explosion risk. An example
of where no other alternative is available due to the physical or
chemical properties of the agent would be where, due to the
environmental characteristics of the end-use, other agents would fail
to vaporize or would not achieve the dispersion required for effective
fire protection. Similarly, use of PFCs due to toxicological concerns
would be appropriate where use of other alternative agents would
violate the workplace safety use conditions set forth in this final
rule. For example, use of a certain agent for explosion suppression in
an occupied area might require high concentrations of an agent that
exceed its LOAEL, or, in cases where egress is precluded such as in
military vehicles during wartime, the required concentration of the
alternatives might exceed their NOAEL. EPA intends that PFCs be used
only as the agent of last resort.
To assist users in their evaluation, EPA has prepared a list of
vendors manufacturing halon substitutes and alternatives. Although
users are not required to report the results of their investigation to
EPA, companies must retain these results in company files for future
reference.
Several commenters requested that narrowed use restrictions on HFC-
23 be lifted because its cardiotoxicity profile is favorable compared
to its design or inerting concentration and in some cases it may be the
only acceptable alternative. As mentioned above, one commenter
suggested that it would be more appropriate to qualify acceptability of
a particular agent with respect to its technical applicability in
defined situations. For example, this commenter identified several
areas where HFC-23 is particularly applicable: (a) Where temperatures
are likely to go below 0 deg. (b) where pre-inerting is required for
occupied areas, and (c) where occupied areas can suffer considerable
variation in fire volume.
Most HFC-23 is a by-product of the manufacture of HCFC-22. While
HCFC-22 is scheduled for a production phaseout under the Clean Air Act
by the year 2020, HCFC-22 is also used as a feedstock for the
manufacture of other products, such as Teflon. Thus, it can be expected
that HFC-23 will likely be inadvertently produced in the future. As
discussed above, Action 40 of the CCAP instructs EPA to limit emissions
of greenhouse gases under the SNAP program. However, because this agent
is typically a byproduct of HCFC-22 production, it is EPA's position
that capture of HFC-23 and use as a fire suppression agent may delay
the effects of this agent in the atmosphere while serving a valuable
purpose. Thus, EPA is lifting the narrowed use restrictions imposed in
the NPRM, and in this FRM EPA is finding acceptable the use of this
agent wherever deemed applicable given technical or market
considerations. However, to control unnecessary emissions of this
agent, EPA recommends that users limit testing only to that which is
essential to meet safety or performance requirements; recover HFC-23
from the fire protection system in conjunction with testing or
servicing; and recycle or destroy agent that is recovered from a
system. EPA is encouraging development of product stewardship programs
by the manufacturer and by Original Equipment Manufacturers (OEMs)
marketing systems containing this agent.
e. Halon categories and subdivisions. Many commenters requested
that EPA remove the subdivisions within the use categories. In other
words, agents should be classified as either ``total flooding'' or
``streaming'' with no further distinction as to their use. This
structure, states one commenter, is consistent with the separation
addressed by UNEP and NFPA. They state that the proposed subdivisions
over-complicate the rule.
For example, in total flood applications, some commenters suggest
simply referring to an agent's NOAEL which, along with OSHA regulations
and NFPA standards, will determine its suitability for a given
application. Thus, there would be no need to distinguish between
normally occupied and normally unoccupied spaces.
EPA is adopting the recommendation of the commenters. Two end-use
categories are used in this final rule: Streaming Agents and Total
Flooding Agents. Explosion inertion is included in the Total Flooding
Agent category.
4. Listing Decisions
In order to evaluate the acceptability of proposed halon
substitutes, the Agency divided the fire protection sector into two
end-uses: (1) Streaming Agents, and (2) Total Flooding Agents. The
`Total Flooding' category includes all total flooding applications,
including normally occupied, normally unoccupied, and explosion
inertion and suppression applications.
For some substitutes, data required by the Agency to complete a
risk assessment is not yet available or has not been submitted to the
Agency as requested. As a result, not all candidate substitutes have
been fully evaluated by the Agency. Those substitutes which the Agency
is currently reviewing, but for which a final determination cannot yet
be made, are listed as pending review in the table in Appendix B. The
evaluation of these pending submissions will continue, and the results
of these continuing evaluations will be published in the Federal
Register as part of EPA's quarterly updates to the SNAP lists.
The listing decisions are compiled by type. Thus, for each end-use,
an agent may be listed in one or more type of decision, including
`acceptable,' `acceptable subject to use conditions,' `acceptable
subject to narrowed use limits,' `unacceptable,' or `pending completion
of review.'
The table in appendix B summarizes EPA's decisions by each type of
decision for each end-use.
EPA's finding of acceptability of a halon substitute should be
viewed only as a listing based on the criteria briefly set out in this
Preamble as governing the SNAP program and described in detail in the
background document entitled ``Characterization of Risk From the Use of
Substitutes for Class I Ozone-Depleting Substances: Fire Extinguishing
and Explosion Protection (Halon Substitutes)''. EPA's finding of
acceptability should not be considered an endorsement of the substitute
for the suppression or prevention of any given fire or explosion
scenario, for which the user is referred to a fire protection
specialist.
a. Acceptable. (1) Streaming agents. (a) HCFC-123. HCFC-123 is
acceptable as a Halon 1211 substitute. Because of its relatively low
weight equivalency, HCFC-123 could replace Halon 1211 at ratio of 1.8
by weight. However, testing has indicated that application of this
agent may require special handling or nozzles to successfully
extinguish a fire. Its extinguishment concentration based on cup burner
tests is 6.3 percent.
With an ODP of 0.02, HCFC-123 has the lowest ODP of all the HCFCs
proposed as halon substitutes, and its 100-year GWP of 90 is lower than
that of other proposed HCFC substitutes. In addition, it has a short
atmospheric lifetime of 2 years. Since HCFC-123 has a cardiotoxic level
(LOAEL) of 2.0 percent in the dog, with no effect (NOAEL) apparent at
1.0 percent, potential users have expressed concern about using HCFC-
123 or blends containing HCFC-123 as the primary constituent. However,
actual exposures were assessed using personal monitoring devices, and
the Agency concludes that likely exposure levels from its use as a
streaming agent do not exceed safe levels when used with good
ventilation. Similar exposure concerns exist with the use of carbon
dioxide or Halon 1211 streaming agents. All must be used only in areas
with adequate ventilation. The manufacturer of portable extinguishers
using these agents should include cautionary language on the label
indicating the need for ventilation.
The manufacturer has raised its allowable exposure limit (AEL) for
HCFC-123 to 30 parts per million (ppm). The AEL is set at a level
believed to protect workers who are regularly exposed from adverse
chronic effects. As a practical matter, exposures should not exceed
this limit for any working day; this practice is consistent with OSHA's
enforcement of its own PELs. If it is likely that exposures may exceed
30 ppm as an 8-hour time-weighted average (TWA), proper protective gear
should be worn. For the purposes of determining the proper respiratory
protection, the user should consult the manufacturer of the product for
their specific recommendations for respirator use of the particular end
use.
As discussed in the section on HCFCs generally, this agent is
subject to regulations under section 610(d) of the CAA. EPA intends to
publish a proposed rulemaking that will ban the use of this agent in
residential applications.
(b) (HCFC blend) B. (HCFC blend) B is acceptable as a Halon 1211
substitute. This blend consists largely of HCFC-123, therefore, as with
HCFC-123, it has been shown in tests to have a weight equivalency ratio
to Halon 1211 of 1.8. While HCFC-123 has a cardiotoxic level of 2.0
percent in the dog, with no effect apparent at 1.0 percent, actual
exposures from use of this blend as a streaming agent were assessed
using personal monitoring devices. The Agency concludes that likely
exposure levels do not exceed safe levels.
The manufacturer of HCFC-123 has raised its allowable exposure
limit (AEL) to 30 parts per million (ppm). The AEL is set at a level
believed to protect workers who are exposed on a regular basis from
chronic adverse effects. As a practical matter, exposures should not
exceed this limit for any working day; this practice is consistent with
OSHA's enforcement of its own PELs.
If it is likely that exposures may exceed 30 ppm as an 8-hour time-
weighted average (TWA), proper protective gear should be worn. To
determine proper respiratory protection, the user should consult the
manufacturer of the product for any specific recommendations governing
respirator use in the particular end-use.
HCFC-123, which is the major component of this blend has an ODP of
0.02, which is the lowest ODP of all the HCFCs proposed as halon
substitutes, and its 100-year GWP of 90 is lower than that of other
proposed HCFC substitutes. Although this agent contains a very small
percentage of PFC, which has a long atmospheric lifetime and which
could potentially contribute to global climate change, EPA believes
that the quantities of PFC likely to be emitted are small, and that
availability of this blend is an important aid in the transition away
from ozone-depleting substances. As with any chemical replacement to
halon, EPA recommends that unnecessary emissions be controlled by
minimizing training and by the use of recycling during maintenance.
As discussed in the section on HCFCs generally, this agent is
regulated under section 610(d). Consistent with the intent of section
610(d), EPA intends to publish a proposed rulemaking that will ban the
use of this agent in residential applications.
(c) (Surfactant blend) A. (Surfactant blend) A is acceptable as a
Halon 1211 substitute. This product is a mixture of organic surfactants
and water. In use, this concentrated mixture is diluted to strengths of
1-10 percent with available water. The surfactants appear to enhance
the heat absorbing capacity of the water.
(Surfactant Blend) A acts on oil, gasoline, and petroleum based
liquid fires (Class B fires) by encapsulating the fuel, thus removing
the fuel source from the fire. This encapsulating feature prevents
flame propagation and reduces the possibility of reignition.
This blend was designed for use on Class B oil and gasoline fires,
but can be used on all Class A and Class B fires, as well as Class D
fires. The agent has passed Underwriters' Laboratories (UL)
certification for Class A, B, and D fires, and UL testing for Class C
fires is underway.
This extinguishant is a blend of complex alcohols, lipids, and
proteins, which are diluted in large volumes of water to the final
commercial preparation. Each of the substances is biodegradable and in
its shipping state the product has been assigned a hazardous materials
identification system (HMIS) rating of 0-0-0 for health hazard,
reactivity, and flammability, respectively. The HMIS rating was
developed by the National Paint and Coatings Association (NPCA) to
indicate the hazard potential of chemical substances, with zero
representing the lowest hazard potential.
Initial data provided by the manufacturer indicate some ocular
irritation in rabbits, and thus EPA is recommending that the
manufacturer label the product with a caution about possible eye
irritation.
(d) Carbon dioxide. Carbon dioxide is acceptable as a Halon 1211
substitute. Carbon dioxide can be used as a direct substitute for Halon
1211 in specified applications. Carbon dioxide systems are not rated
for Class A fires and so must be used in conjunction with another type
of extinguisher to ensure that all possible fires can be extinguished.
In addition, discharge of carbon dioxide into confined spaces may
result in CO2 concentrations above the Immediately Dangerous to
Life and Health (IDLH) level. Areas into which carbon dioxide is
discharged should be immediately evacuated and ventilated. Carbon
dioxide extinguishers should be used only in accordance with
manufacturer's guidelines and applicable NFPA standards.
(e) Dry chemical. Dry chemical extinguishers are acceptable as
Halon 1211 substitutes. Dry chemical extinguishers can be used as a
substitute for Halon 1211 in most residential applications. While dry
chemical extinguishers can be used on Class A, B, or C fires depending
upon the type of powder used, they do not always penetrate well around
obstacles, they do not inhibit re-ignition of fires, they do not cool
surfaces, they can cause secondary damage, and discharge in confined
spaces can result in temporary loss of visibility. Dry chemical
extinguishers should be used only in accordance with manufacturer's
guidelines and with relevant NFPA standards.
(f) Water. Water is acceptable as a Halon 1211 substitute. Users
should be aware, however, that water extinguishers cannot act as a
substitute for Halon 1211 in all applications. Water is primarily a
Class A fire extinguishant. It can be used on de-energized Class C
fires, but should not be used with Class B fires. Water may damage
objects onto which it is discharged. Water extinguishers should be used
only in accordance with manufacturer's guidelines and with applicable
NFPA standards.
(g) Foam. Foam is acceptable as a Halon 1211 substitute. Foam
extinguishers cannot be used as a substitute for halon in all
applications. Portable foam extinguishers are intended primarily for
use on flammable liquid fires and are somewhat effective on Class A
fires. Foam can also cause secondary damage on objects onto which it is
discharged. Foam extinguishers should be used in accordance with
manufacturer's guidelines and with NFPA standards.
(2) Total flooding agents. (a) Carbon dioxide. Carbon dioxide is
acceptable as a Halon 1301 substitute. Exposure to carbon dioxide poses
an imminent threat to life. However, because it displaces oxygen, it is
an effective fire protection agent. As a result, both OSHA and the NFPA
address CO2 systems for occupied areas. OSHA 1910.162(b)5 requires
a pre-discharge alarm for systems with a design concentration of 4
percent or greater. NFPA has written a standard (NFPA 12) that
explicitly controls how such CO2 systems may be safely used in
occupied areas. To protect life, the standard requires a system design
such that no personnel may be present upon system discharge. The EPA
recognizes both the OSHA regulation and the NFPA standard as industry
practice and therefore defer to them in this rule. CO2 systems
require a storage volume of three times that of Halon 1301.
In the review of proposed substitutes, the Agency looks at a
variety of health and environmental factors, including whether the
agent contributes to global climate change. While carbon dioxide is a
greenhouse gas, it is also a byproduct of many industrial processes and
is recaptured and reformulated as a fire fighting agent and thus does
not require new production. Therefore, the Agency has determined that
its contribution to overall greenhouse gas emissions is low.
(b) Water. Water sprinkler systems are acceptable as a Halon 1301
substitute. Such systems are in widespread use and are governed by NFPA
technical standards. EPA encourages adoption of water systems wherever
feasible. Care should be taken when using water on Class C electrical
fires, and it may not be suitable in instances in which secondary
damage is considered unacceptable.
(c) (Inert Gas Blend) B is acceptable for use in unoccupied areas.
The decision for use of this agent in occupied areas is pending until
the agency completes its review of low oxygen atmospheres, and will be
included in a future rulemaking. Use conditions to limit the risk of
inadvertent exposure to personnel in normally unoccupied areas may be
included in future rulemakings.
(d) (Powdered Aerosol) A is acceptable for use in unoccupied areas.
The decision for use of this agent in occupied areas is pending until
the agency completes its review of the potential health effects of this
agent. In addition, use conditions to limit the risk of inadvertent
exposure to personnel in normally unoccupied areas may be included in
future rulemakings.
(e) (Powdered Aerosol) B is acceptable for use in unoccupied areas.
This SNAP submission included many different formulations. While the
formulations pose little risk in a normally unoccupied area, the
decision for use of the various formulations in occupied areas is
pending further review of their potential health effects. In addition,
use conditions to limit the risk of inadvertent exposure to personnel
in normally unoccupied areas may be included in future rulemakings.
b. Acceptable subject to use conditions. (1) Total flooding agents.
In analyzing the acceptability of substitutes for total flooding
applications in occupied spaces, the Agency considered cardiotoxicity
one of the primary decision variables. Current OSHA limitations on use
of Halon 1301 in total flooding applications assure that these uses do
not pose a cardiotoxic risk to personnel at the design concentration.
OSHA promulgated a safety and health standard (29 CFR 1910 subpart
L) governing fire protection systems used at all workplaces which is
designed to limit employee exposures to toxic levels of gaseous agents
used in fixed total flood systems. OSHA section 1910.162 governs the
use of all gaseous agents in fixed extinguishing systems, however the
guidance is not explicit on the allowable concentrations of the
different agents. While paragraph 1910.162(b)3 stipulates that ``[t]he
employer shall assure that employees are not exposed to toxic levels of
gaseous agent or its decomposition products,'' it does not define what
a ``toxic level'' is. In examining paragraph 1910.162(b)(6)(i) through
(b)(6)(iii), EPA concludes that it is OSHA's intent to limit exposure
to gaseous agents based upon cardiotoxicity levels. EPA's conclusion
was confirmed in discussions with OSHA. EPA's assessment is that the
use of NOAEL/LOAEL values based on exposure scenarios is the proper
method to ensure safe use of gaseous agents, and agrees with OSHA's
approach. It is therefore EPA's intention to stipulate the cardiotoxic
levels for each agent and, until OSHA incorporates clarifying language
for the new agents, to impose use conditions that apply 1910.162 in its
entirety to these agents.
References in Sec. 1910.162 to a Halon 1301 concentration of 7
percent imply a cardiotoxic NOAEL, and references to a Halon 1301
concentration of 10 percent imply a cardiotoxic LOAEL. In this
regulation, EPA is clarifying the intent of Sec. 1910.162(b)(3) to
allow the use of the substitute gaseous agents only according to
paragraph (b)(6)(i) through (b)(6)(iii), using the cardiotoxic NOAEL
and LOAEL of each agent as the concentration referenced in each
subparagraph.
In addition, existing OSHA standard 1910.160 applies certain
general controls to the use of fixed extinguishing systems in occupied
workplaces, whether gaseous, dry chemical, water sprinklers, etc., and
EPA has not reproduced those. These include, for example, the
requirements for discharge and pre-discharge alarms, and availability
of Self Contained Breathing Apparatus (SCBA) for emergency entry into
an area where agent has been discharged.\2\
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\2\29 CFR 459, Sec. 1910.160, paragraph (b) includes general
provisions to ensure the safety of all fixed extinguishing systems.
Paragraph (c) stipulates requirements for systems with ``potential
health and safety hazards to employees'' such as might be posed by
gaseous agents.
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In many occupied areas, total flooding halons can be replaced by
improved detection equipment and manually operated extinguishing
systems. Improved detection systems, if they detect fires in their
early stages, can alert occupants to the existence of a fire so they
may respond appropriately without discharge of the total flood system.
In those cases in which a total flooding system is deemed necessary,
improved detection systems can also reduce false alarms that result in
the unnecessary discharge of total flooding systems.
In unoccupied areas, human exposure to potentially toxic
substitutes or decomposition products are of less concern. The key
criterion in the SNAP decision process therefore becomes environmental
considerations. At the same time, the Agency must ensure that personnel
are not exposed to toxic concentrations of fire protection agents or
their decomposition products when the substances are vented or leak out
from the extinguishment area. Precautions must also be taken to prevent
exposures to personnel entering a normally unoccupied area after a
discharge. In addition, if there is a possibility that someone must
enter a room while an agent is likely to exceed the NOAEL level, SCBA
must be worn.
Design concentrations for explosion inertion must be higher than
for fire suppression. In addition, design concentrations vary depending
on the combustible material being considered. Thus, the system designer
must be careful to ensure that system design precludes unacceptable
cardiotoxic or oxygen depletion levels.
Explosion inertion agents are currently regulated by OSHA through
the general duty clause\3\, but use conditions are not explicitly
stated as they are for fire suppression systems. However, since design
concentrations for systems protecting against explosion of various
gases or flammable liquids may expose personnel to cardiotoxic levels
of inertion agents, it is industry practice to adopt standards provided
under OSHA 1910.162. EPA is not intending to impose new regulations in
this area, but defers to current OSHA practice in this regard, with the
stipulation that the NOAEL and LOAEL values identified in this Final
Rulemaking are the reference values for exposure limits.
---------------------------------------------------------------------------
\3\Public Law 91-596, (29 U.S.C. 654), section 3, is known as
the ``general duty clause:''
(1) shall furnish to each of is employees employment and a place
of employment which are free from recognized hazards that are
causing or are likely to cause, death or serious physical harm to
his employees;
(2) shall comply with occupational safety and health standards
promulgated under this Act.
---------------------------------------------------------------------------
Until OSHA establishes applicable workplace requirements, total
flooding agents are acceptable by the Agency for use in occupied areas
only under the following conditions:
1. Where egress from an area cannot be accomplished within one
minute, the employer shall not use the agent in concentrations
exceeding its NOAEL.
2. Where egress takes greater than 30 seconds but less than one
minute, the employer shall not use the agent in a concentration greater
than its LOAEL.
3. Agent concentrations greater than the LOAEL are only permitted
in areas not normally occupied by employees provided that any employee
in the area can escape within 30 seconds. The employer shall assure
that no unprotected employees enter the area during agent discharge.
These conditions will no longer apply once OSHA establishes applicable
workplace requirements.
(a) HBFC-22B1. HBFC-22B1 is acceptable as a Halon 1301 substitute.
This agent is subject to the use conditions delineated in the
discussion of total flooding agents in this section. HBFC-22B1 can
replace Halon 1301 at a ratio of 1.4 by weight and 1.3 by storage
volume, making it technically suitable for use in existing total flood
systems. Its required extinguishing concentration, based on the cup
burner test in heptane, is estimated at 4.4 percent, and its design
concentration is 5.3 percent. Its explosion inertion concentration is
8.0 percent. The LOAEL for cardiotoxicity is 1 percent while its NOAEL
is 0.3 percent. Its atmospheric lifetime is 7 to 15 years, but its GWP
is uncalculated. This compound is unlikely to be feasible as a total
flooding agent in occupied areas because its design concentration
exceeds its cardiotoxic effect level.
While HBFC-22B1 has an ODP of 0.74 and will be phased out on
January 1, 1996, the Agency believes that the substance can serve a
useful role in helping users transition away from Halon 1301, which has
a much higher ODP, estimated at 10.
This agent was submitted to the Agency as a Premanufacture Notice
(PMN) and is presently subject to requirements contained in a Toxic
Substance Control Act (TSCA) section 5(e) Consent Order and associated
Significant New Use Rule (40 CFR 721.1296).
(b) HCFC-22. HCFC-22 is acceptable as a Halon 1301 substitute. This
agent is subject to the use conditions delineated in the discussion of
total flooding agents in this section. HCFC-22 has an extinguishment
concentration, as determined by cup burner in heptane, of 11.6 percent
and a design concentration of 13.9 percent, the highest of the
candidate HCFCs. Its estimated explosion inertion concentration is 18.8
percent. Its weight and volume equivalence are 2.4 percent and 3.0
percent, respectively. The cardiotoxic NOAEL is 2.5 percent and its
LOAEL is 5.0 percent. This compound is unlikely to be feasible as a
pure agent in occupied areas because its design concentration exceeds
its cardiotoxic effect level.
The ODP for HCFC-22 is 0.05, the 100 year-GWP is 1600, and the
atmospheric lifetime is 16 years. Its ODP and GWP are both higher than
those for other candidate HCFCs. This agent is schedule for production
phaseout under the CAA for new equipment in the year 2010 and for
existing equipment in the year 2020 (58 FR 65018).
(c) HCFC-124. HCFC-124 is acceptable as a Halon 1301 substitute.
This agent is subject to the use conditions delineated in the
discussion of total flooding agents in this section. HCFC-124 has
relatively low ODP of .022, and, compared to other candidate 1301
substitutes for which GWP has been estimated, has a relatively low 100-
year GWP value of 440 with an atmospheric lifetime of 7 years. Animal
testing indicates that the substance may be lethal to rats at a level
greater than 23 percent over a four hour period. The substance has a
cardiotoxic LOAEL of 2.5 percent and a NOAEL apparent at 1.0 percent.
Its weight and volume equivalence is 2.6 and 2.9 respectively. The
extinguishing concentration based on cup burner tests in heptane of
HCFC-124 is 7.0 percent and its design concentration is 8.4 percent,
while its explosion inertion concentration is 12.0 percent. This
compound is unlikely to be feasible as a total flooding agent in
normally occupied areas because its design concentration exceeds its
cardiotoxic level.
(d) (HCFC BLEND) A. (HCFC BLEND) A is acceptable as a Halon 1301
substitute. This agent is subject to the use conditions delineated in
the discussion of total flooding agents in this section. Based on full-
scale testing, the extinguishing concentration of this blend has been
determined to be approximately 7.2 percent and therefore the design
concentration is approximately 8.6 percent. The cardiotoxic NOAEL of
this blend is 10.0 percent, and the LOAEL is at least 10.0 percent.
Until further data is supplied, the Agency considers its LOAEL to be 10
percent. The major component of this blend has an ODP of 0.05, higher
than other proposed HCFC substitutes, but the blend appears somewhat
more effective from a weight and storage volume equivalency basis,
which is 1.6 and 2.3 respectively. This compound is a feasible
candidate for use in a normally occupied area.
This agent is a blend of different HCFCs. The predominant component
of this blend is HCFC-22, which has an ODP of 0.05, an atmospheric
lifetime of 16 years, and a GWP of 1600. HCFC-22 is scheduled for
production phaseout under the CAA by the year 2020 and all other HCFCs
by the year 2030 (58 FR 65018).
(e) HFC-23. HFC-23 is acceptable as a Halon 1301 substitute. This
agent is subject to the use conditions delineated in the discussion of
total flooding agents in this section.
HFC-23 is attractive for use as a total flooding agent in occupied
areas because the cardiotoxic NOAEL is at least 30 percent without
added oxygen and over 50 percent with added oxygen, compared to a
design concentration of 14.4 percent, based on cup burner tests in
heptane. EPA recognizes that no cardiotoxic effect was measured in the
tests of HFC-23, and acknowledges that tests were terminated when
oxygen levels decreased to a point posing risk of asphyxiation.
However, EPA must examine this agent in the light of potential
cardiotoxicity because this is a halocarbon which does possess
cardiotoxic characteristics. It is an artifact of the test protocol
that determines that the NOAEL and LOAEL must be interpreted from the
data, and not interpolated. To observe a cardiotoxic effect would
require quantities in such high concentration as to pose a risk of
asphyxiation before risk of cardiotoxicity. Because testing was stopped
at 30 percent without added oxygen and 50 per cent with added oxygen,
EPA must use these values as the maximum allowable concentrations. In
the NPRM, EPA did not refer to a specific LOAEL for this agent.
However, the standard OSHA-derived language was included for all
agents. In this rulemaking, EPA is using the values of 30 percent for
the NOAEL and 50% for the LOAEL.
Compared to an inerting concentration in methane of 20.5 percent
and an inerting design concentration of 22.6 percent in methane, this
agent is an excellent candidate for use in explosion inertion.
As mentioned earlier, the risk of using agents in high
concentrations poses a risk of asphyxiation by displacing oxygen. With
an ambient oxygen level of 21 percent, a design concentration of 22.6
percent will reduce oxygen levels to approximately 16 percent, the
minimum oxygen level considered to be required to prevent impaired
judgement or other physiological effects. The weight equivalent of HFC-
23 is 1.6 while its storage volume equivalent is 2.6. This agent
requires a high pressure system for proper discharge and dispersion.
Because this agent has an atmospheric lifetime of about 280 years
and a 100-year GWP of 9,000, it is considered a potent greenhouse gas
and should be handled accordingly. Since HFC-23 is typically a by-
product of manufacturing and is not expressly produced for use as a
fire fighting agent, EPA is allowing the use of this agent wherever
applicable given technical or market considerations. However, in order
to minimize unnecessary emissions of greenhouse gases, EPA recommends
that users limit testing only to that which is essential to meet safety
or performance requirements; recover HFC 23 from the fire protection
system in conjunction with testing or servicing; and destroy or recycle
HFC-23 for later use. In addition, EPA encourages manufacturers to
develop aggressive product stewardship programs to help users avoid
such unnecessary emissions.
(f) HFC-125. HFC-125 is acceptable as a Halon 1301 substitute. This
agent is subject to the use conditions delineated in the discussion of
total flooding agents in this section. The cardiotoxic NOAEL for HFC-
125 is 7.5 percent, and its LOAEL is 10.0 percent compared to a cup
burner extinguishment concentration in heptane of 9.4 percent. While
this agent would not be appropriate for use in normally occupied areas,
it is not expected that human health would be threatened by use of HFC-
125 in normally unoccupied areas. This agent has a weight and volume
equivalence of 2.6 and 3.2, respectively.
HFC-125 does not deplete stratospheric ozone. Despite its zero ODP,
HFC-125 has an atmospheric lifetime of 41 years, and the highest
calculated GWP (100-year GWP of 3,400) than any other HFC (except HFC-
23) or HCFC currently planned for production as a halon or CFC
substitute.
(g) HFC-134a. HFC-134a is acceptable as a Halon 1301 substitute.
This agent is subject to the use conditions delineated in the
discussion of total flooding agents in this section. HFC-134a has a
cardiotoxic NOAEL of 4.0 percent, a LOAEL of 8 percent, and a design
concentration of 12.6 percent. This compound is unlikely to be feasible
as a total flooding agent in occupied areas because its design
concentration exceeds its cardiotoxic level. Like the other HFCs, HFC-
134a has an ODP of zero. It also has among the lowest GWP of the
candidate 1301 replacements for which GWP has been estimated, with a
100-year GWP of 1,200 and an atmospheric lifetime of 16.
Cup burner tests in heptane indicate that this substance is less
effective than 1301. Systems that use HFC-134a will require
approximately 2.5 times more extinguishant by weight and 3.1 times more
storage volume than 1301 systems.
(h) HFC-227ea. HFC-227ea is acceptable as a Halon 1301 substitute.
This agent is subject to the use conditions delineated in the
discussion of total flooding agents in this section. The final report
on cardiotoxicity of HFC-227ea indicates that its NOAEL is 9.0 percent
and that its LOAEL is at least 10.5 percent. EPA is accepting 10.5
percent as its LOAEL. Cup burner tests with heptane indicate that the
extinguishment concentration for this agent is 5.8 percent, thus making
its calculated design concentration 7.0 percent. These concentrations
provide a sufficient margin of safety for use in a normally occupied
area. HFC-227ea does not deplete stratospheric ozone. In addition, HFC-
227ea is the most effective of the proposed HFC substitutes for Halon
1301. HFC-227ea can replace Halon 1301 at a ratio of 1.7 by weight and
1.4 by volume.
HFC-227ea has a 100-year GWP of about 2,050, with an atmospheric
lifetime of 31 years.
(i) C4F10. C4F10 is acceptable as a Halon 1301
substitute where other alternatives are not technically feasible due to
performance or safety requirements: (a) due to their physical or
chemical properties or (b) where human exposure to the agents may
approach cardiosensitization levels or result in other unacceptable
health effects under normal operating conditions. This agent is subject
to the use conditions delineated in the preceding discussion. In
addition, because this agent can be used in high concentrations due to
its cardiotoxicity profile, the design concentration must result in
oxygen levels of at least 16%.
Cup burner tests in heptane indicate that C4F10 can
extinguish fires in a total flood application at concentrations of 5.5
percent and therefore has a design concentration of 6.6 percent. The
cardiotoxicity NOAEL of 40 percent for this agent is well above its
extinguishment concentration and therefore is safe for use in occupied
areas. This agent has a weight and volume equivalence of approximately
3.1 and 3.0 respectively.
Using agents in high concentrations poses a risk of asphyxiation by
displacing oxygen. With an ambient oxygen level of 21 percent, a design
concentration of 22.6 percent may reduce oxygen levels to approximately
16 percent, the minimum level considered to be required to prevent
impaired judgment or other physiological effects. Thus, the oxygen
level resulting from discharge of this agent must be at least 16
percent.
This agent has an atmospheric lifetime of 2,600 years and a 100-
year GWP of 5,500. Due to the long atmospheric lifetime of
C4F10, the Agency is finding this chemical acceptable only in
those limited instances where no other alternative is technically
feasible due to performance or safety requirements. In most total
flooding applications, the Agency believes that alternatives to
C4F10 exist. EPA intends that users select C4F10
out of need and that this agent be used as the agent of last resort.
Thus, a user must determine that the requirements of the specific end
use preclude use of other available alternatives.
Users must observe the limitations on C4F10 acceptability
by undertaking the following measures: (i) Conduct an evaluation of
foreseeable conditions of end use; (ii) determine that human exposure
to the other alternative extinguishing agents may approach or result in
cardiosensitization or other unacceptable toxicity effects under normal
operating conditions; and (iii) determine that the physical or chemical
properties or other technical constraints of the other available agents
preclude their use.
Some examples of potential end-uses where toxicity may possibly be
of concern are: i. Applications involving confined spaces where egress
is difficult, such as in civilian and military transportation
applications including aircraft engines, armored vehicles (engine and
crew compartments), and ship engines; ii. Applications where public
safety or national security necessity may preclude personnel from
evacuating, in event of emergency, such as nuclear power plants or
guard/security facilities; iii. Explosion and fire protection
applications where high suppression or inerting concentrations are
required such as processing and pump stations, flammable liquid
processing areas, and flammable metal processing areas; iv. Health care
facility applications involving impaired populations, such as hospitals
and nursing homes where there may be a preference for use of this agent
due to the unique concerns within the facility; v. Military mission
critical applications which are vital to national security; vi. Other
applications where, due to physical or chemical properties, there are
no other technically feasible alternatives.
EPA recommends that users minimize unnecessary emissions of this
agent by limiting testing of C4F10 to that which is essential
to meet safety or performance requirements; recovering C4F10
from the fire protection system in conjunction with testing or
servicing; and destroying or recycling C4F10 for later use.
EPA encourages manufacturers to develop aggressive product stewardship
programs to help users avoid such unnecessary emissions.
(j) IG-541. IG-541 is acceptable as a Halon 1301 substitute. This
agent is subject to the use conditions delineated in the discussion of
total flooding agents in this section. In the NPRM, this agent was
referred to as (Inert Gas Blend) but is now referred to as IG-541,
consistent with NFPA 2001. This agent is a non-reactive, non-halocarbon
substance, and thus not carcinogenic, mutagenic, or teratogenic; the
toxicity and cardiotoxicity tests normally applied to halon substitutes
do not apply here. Rather, this agent is a potential asphyxiant, since
it is designed to decrease the oxygen to a level at which combustion
cannot be supported. This blend is designed to increase breathing
rates, thus making the oxygen deficient atmosphere breathable for short
periods of time. Data submitted by the manufacturer was peer-reviewed
by pulmonary, cardiac, and stroke specialists. All have agreed that the
blend does not pose significant risk to the working population and may
even pose less risk than does exposure to halocarbon agents. However,
to ensure safety, this blend is acceptable under the conditions that
the design concentration results in at least 10 percent oxygen and 5
percent carbon dioxide. In addition, if the oxygen concentration of the
atmosphere falls below 10 percent, personnel must be evacuated and
egress must occur within 30 seconds. Since a fire can be expected to
consume oxygen and form decomposition products, personnel should treat
any fire situation as an emergency and promptly exit the space.
A fire suppression design concentration of 52 percent and 43
percent would result in oxygen levels of 10 percent and 12 percent,
respectively. The inerting concentration for this blend is 44 percent
for methane/air mixtures and 50 percent for propane/air mixtures. A 50
percent concentration would result in an atmosphere of only 10.5
percent oxygen content, which is at the lower limit of acceptability of
this agent.
Concerns have been raised about the decibel level of this system
upon discharge. The manufacturer has submitted a report indicating the
decibel level to be 117 decibels for 3 seconds followed by a decay in
noise level over 5 minutes, compared to 130 decibels for a typical
halon system. The Time Weighted Average (TWA) of this system is 57
decibels. These levels are in compliance with the OSHA workplace
maximum allowed peak of 140 decibels and a maximum Time Weighted
Average (TWA) of 90 decibels. This acceptability listing for use of IG-
541 does not apply to any other inert gas system. A manufacturer with a
different formulation must prepare a separate SNAP submission to EPA.
c. Acceptable subject to narrowed use limits. (1) Streaming agents.
(a) HBFC-22B1. HBFC-22B1 is acceptable as a Halon 1211 substitute in
non- residential applications. HBFC-22B1 is unacceptable for use in
residential applications.
Extinguishment testing indicates that HBFC-22B1 can replace Halon
1211 at a ratio of 1.1 by weight, making it a viable substitute for use
in hand-held extinguishers. Despite its high ODP of 0.74, this chemical
can facilitate the shift away from Halon 1211, which has an even higher
ODP of 3.0. However, given the potential market penetration and the
high ODP of HBFC-22B1, widespread use of HBFC-22B1 in consumer
applications was estimated to cause unacceptable damage to the ozone
layer and an excessively high number of skin cancer cases and deaths.
The total estimated skin cancer cases and fatalities from the use of
HBFC-22B1 as a Halon 1211 replacement in all uses including consumer
uses is approximately 30,000 and 600, respectively.
In addition to concern about its ODP, use of HBFC-22B1 in
residential applications may present risks of cardiosensitization. To
assess this risk, the Agency modeled the peak concentration of HBFC-
22B1 that would be expected if such an extinguishant were used to
suppress a kitchen fire and estimated the decline from the peak. Such
analysis indicated that peak concentrations of HBFC-22B1 would exceed
3300 ppm. This is in excess of NFPA ceilings for exposure. In light of
the availability of other fire protection agents with lower associated
risks, the Agency determined that the risks posed by HBFC-22B1 were too
large to justify widespread use in the consumer sector. Thus, EPA finds
HBFC-22B1 unacceptable for use in residential applications since other
viable alternatives exist.
Worker exposure may be a concern in small enclosed areas, but in
larger areas and outdoors, modeling efforts indicate that HBFC-22B1 can
be used safely. In most realistic fire scenarios, proper procedures
should be in place regarding the operation of the extinguisher and
workers will be properly trained in fire fighting procedures and
ventilation of extinguishment areas can be expected after dispensing
the extinguishant.
Because it represents one of the few available substitutes in
specific end-uses, EPA is finding use of HBFC-22B1 acceptable as a
streaming agent except for residential uses. However, it can only be
considered a transitional agent, because it will be phased out as a
class I substance beginning January 1, 1996, in accordance with the
Clean Air Act and with the requirements of the Montreal Protocol.
This agent was submitted to the Agency in a Premanufacture Notice
(PMN) and is presently subject to requirements contained in a Toxic
Substance Control Act (TSCA) section 5(e) Consent Order and associated
Significant New Use Rule (40 CFR 721.1296). Under the terms of the
Consent Order, it may be used only for outdoor automotive and marine
applications. In addition, to ensure safe use, the sale of this product
is restricted to a size discouraging residential use, with a minimum UL
rating of 5BC. The unit must be properly labeled. The label must ban
residential use, indicate space volume restrictions that would limit
exposure to 1 percent, and describe proper evacuation and reentry
requirements. In addition, the agent may only be sold in rechargeable
units to encourage reuse and recycling and to minimize the potential
for the agent to escape to the atmosphere through improper disposal.
(b) (CFC Blend). (CFC Blend) is acceptable as a Halon 1211
substitute in non-residential applications. While this agent was listed
in the SNAP NPRM as proposed acceptable, the sale and distribution of
CFCs in pressurized dispensers (in this sector, portable fire
extinguishers) are controlled under section 610 of the CAA. The section
610 final rulemaking (58 FR 4768, January 15, 1993) bans the use of
CFCs in portable fire extinguishers. Therefore, in the upcoming
proposed SNAP rulemaking, EPA will list this agent as proposed
unacceptable due to section 610 prohibitions.
This agent is unacceptable for use in residential applications
since other viable alternatives exist. (CFC-Blend) contains CFCs with
ODPs of 1.0. The predominant constituent has a 100-year GWP of 3400,
with an atmospheric lifetime of 55 years. The CFC constituent in this
blend will be phased out of production on December 31, 1995.
This agent is the most effective of all other halon substitutes
except for HBFC-22B1 and HCFC-123, and does not pose the exposure risk
of HBFC-22B1 in certain scenarios. (CFC Blend) is generally considered
non-toxic and could serve as a transitional substitute in many
streaming applications. However, in light of its high ODP relative to
other substitute agents and the large potential market for consumer/
residential extinguishers, alternative agents such as water and dry
chemical are considered sufficient for residential uses.
(c) C6F14. C6F14 is acceptable as a streaming
agent in non-residential applications: Where other alternatives are not
technically feasible due to performance or safety requirements: (a) Due
to the physical or chemical properties of the agent, or (b) where human
exposure to the extinguishing agent may approach cardiosensitization
levels or result in other unacceptable health effects under normal
operating conditions. This agent is unacceptable for use in residential
applications and for uses beyond the limits and conditions stipulated
in this action.
The extinguishment concentration of C6F14 is 4.4 percent,
and a cardiotoxicity NOAEL of 40 percent. Its weight equivalence is 2.8
and its storage volume equivalence is 3.1. While C6F14 has no
ODP, its atmospheric lifetime is 3,000 years, and may potentially
contribute to global climate change.
EPA intends that users select C6F14 out of need and that
this agent be used as the agent of last resort. Thus, a user must
determine that the characteristics of the end-use preclude use of other
available alternatives. In most streaming applications, the Agency
believes that alternatives to C6F14 exist. These include the
halocarbon replacements identified above as well as alternative agents
such as water, CO2, foam, and dry chemicals. Users should attempt
to use these other agents before deciding on an C6F14 system.
At the time of publication of this rulemaking, EPA is unaware of any
data which necessitates the use of any PFC as a streaming agent based
on toxicological concerns.
Users must observe the limitations on C6F14 acceptability
by undertaking the following measures: (i) Conduct an evaluation of
foreseeable conditions of end use; (ii) determine that human exposure
to the other alternative extinguishing agents may pose a risk of
cardiosensitization or other unacceptable toxicity effects under normal
operating conditions; and (iii) determine that the physical or chemical
properties or technical constraints of the other available agents
preclude their use. Users must maintain documentation on measures taken
to justify use of this agent.
Some examples of potential end-uses where toxicity or physical
characteristics may possibly be of concern are: i. Confined spaces
which are difficult to egress, such as civilian and military
transportation applications, including armored vehicles, marine
engines, power boats, aircraft cabins, and race cars; ii. Applications
where public safety or national security necessity may preclude
personnel from evacuating, in event of emergency, such as nuclear power
plants or guard/security facilities; iii. Emergency response
applications such as crash rescue vehicles and aircraft flightlines;
iv. Military applications involving mission critical applications which
are vital to national security; v. Other applications where, due to
physical or chemical properties, there are no technically feasible
alternatives.
EPA recommends that users minimize unnecessary emissions by
limiting testing only to that which is essential to meet safety or
performance requirements; recovering C6F14 from the fire
protection system in conjunction with testing or servicing; and
destroying C6F14 or recycling it for later use. EPA
encourages manufacturers to develop aggressive product stewardship
programs to help users avoid such unnecessary emissions.
(2) Total Flooding Agents. (a) C4F10. C4F10 is
acceptable as a Halon 1301 substitute (i) where other alternatives are
not technically feasible due to performance or safety requirements: (a)
Due to their physical or chemical properties or (b) where human
exposure to the agents may approach cardiosensitization levels or
result in other unacceptable health effects under normal operating
conditions. This agent is subject to the use conditions delineated in
the preceding discussion concerning use to total flooding agents in the
workplace. In addition, because this agent can be used in high
concentrations due to its cardiotoxicity profile, the design
concentration must result in oxygen levels of at least 16%.
Cup burner tests in heptane indicate that C4F10 can
extinguish fires in a total flood application at concentrations of 5.5
percent with a design concentration of 6.6 percent. The cardiotoxicity
NOAEL of 40 percent for this agent is well above its extinguishment
concentration and therefore is safe for use in occupied areas.
Using agents in high concentrations poses a risk of asphyxiation by
displacing oxygen. With an ambient oxygen level of 21 percent, a design
concentration of 22.6 percent may reduce oxygen levels to approximately
16 percent, the minimum level considered to be required to prevent
impaired judgement or other physiological effects. Thus, the oxygen
level resulting from discharge of this agent must be at least 16
percent.
While C4F10 has a no ODP, it has an atmospheric lifetime
of 2,600 years. Due to its long atmospheric lifetime, the Agency is
finding this chemical acceptable only in those limited instances where
no other alternative is technically feasible due to performance or
safety requirements. In most total flooding applications, the Agency
believes that alternatives to C4F10 exist. It is EPA's
intention that users not select C4F10 out of simple
preference, but out of need and that this agent be used as the agent of
last resort. Thus, a user must determine that the requirements of the
specific end-use preclude utilization of other available alternatives.
Users must observe the limitations on PFC use by undertaking the
following measures: (i) Conduct an evaluation of foreseeable conditions
of end use; (ii) determine that human exposure to the other alternative
extinguishing agents may approach or result in cardiosensitization or
other unacceptable toxicity effects under normal operating conditions;
and (iii) determine that the physical or chemical properties or other
technical constraints of the other available agents preclude their use.
Some examples of potential end-uses where toxicity may possibly be
of concern are: i. Applications involving confined spaces where egress
is difficult, such as in civilian and military transportation
applications including aircraft engines, armored vehicles (engine and
crew compartments), and ship engines; ii. Applications where public
safety or national security necessity may preclude personnel from
evacuating, in event of emergency, such as nuclear power plants or
guard/security facilities; iii. Explosion and fire protection
applications where high suppression or inerting concentrations are
required such as processing and pump stations, flammable liquid
processing areas, and flammable metal processing areas; iv. Health care
facility applications involving impaired populations, such as hospitals
and nursing homes where there may be a preference for use of this agent
due to the unique concerns within the facility; v. Military mission
critical applications which are vital to national security; vi. Other
applications where, due to physical or chemical properties, there are
no other technically feasible alternatives.
EPA recommends that users minimize unnecessary emissions by
limiting testing of C4F10 to that which is essential to meet
safety or performance requirements; recovering C4F10 from the
fire protection system in conjunction with testing or servicing; and
destroying or recycling C4F10 for later use. In addition, EPA
encourages manufacturers to develop aggressive product stewardship
programs to help users avoid such unnecessary emissions.
b. Unacceptable substitutes. (1) Streaming agents. (a) (CFC-11).
CFC-11 is unacceptable in its proposed application as a Halon 2402
substitute or for use in controlling large outdoor fires. This agent
has been proposed as a substitute for Halon 2402, as well as for use in
controlling large outdoor fires, as when dropped from helicopters.
Halon 2402 is not used in the U.S. and thus does not require a
substitute agent. Other nonozone-depleting methods are already in use
in fighting these large outdoor fires and, thus, EPA does not believe
that introduction of this substitute is warranted.
(2) Total flooding agents. There are no total flooding agents
listed as unacceptable.
H. Sterilants
1. Overview
CFC-12 is widely used in combination with ethylene oxide (EtO) to
sterilize medical equipment and devices. The most prevalent combination
consists of 12 percent EtO mixed with 88 percent CFC-12; the mixture is
therefore referred to as ``12/88''. EtO serves as the actual sterilant
in this mixture and can be used alone as a sterilant, but by itself,
EtO is highly flammable. CFC-12 acts as a diluent to form a non-
flammable blend.
Sterilants, including 12/88, are used in a variety of applications.
These include hospital sterilization, medical equipment sterilization,
pharmaceutical production, spice fumigation, commercial research and
development, and contract sterilization. Hospitals are by far the most
numerous users of sterilants. Within hospitals, 12/88 is the most
popular sterilant. Estimates indicate that in 1989, EtO/CFC-12 was used
for over 95 percent of all sterilization in hospitals. Other individual
users of sterilant such as contract sterilizers and pharmaceutical
producers, while less numerous than hospitals, typically consume more
sterilant than the average hospital but are more likely to use other
alternatives such as pure EtO sterilization.
Despite the varied end uses of sterilants, the Agency did not
divide its analysis and regulation of the sterilants sector into
distinct end uses. This is because alternatives to 12/88 are consistent
across end uses, and the sterilant sector as a whole represents one of
the smallest use sectors for Class I substances being considered in the
SNAP program. On an ODP-weighted basis, US consumption of CFC-12 for
sterilization represented less than 4 percent of the total US
consumption of ozone depleting substances in 1990.
Several alternatives to 12/88 are currently in widespread use, but
each is limited in applicability by material properties of the devices
to be sterilized. These currently available alternatives are unlikely
to serve as widespread substitutes for 12/88. Steam sterilizers, for
example, are used in many applications and are less expensive to
purchase and operate than 12/88 systems. However, steam can only be
used to sterilize equipment that can resist high temperatures and high
humidity. Pharmaceutical manufacturers already use steam to the maximum
extent possible, but hospitals may be able to shift some of their
current 12/88 use to steam by separating heat and moisture-resistant
devices from sensitive ones. Other alternatives such as radiation,
peracetic acid, and glutaraldehyde are also in use, but, like steam,
are incompatible with many of the materials now sterilized with 12/88.
For example, 30 to 50 percent of new products are initially sterilized
with gamma radiation, but it is not possible to re-sterilize hospital
surgical equipment with gamma radiation. Rather, 12/88 must be used.
Several other alternatives, such as chlorine dioxide, gaseous
ozone, vapor phase hydrogen peroxide, and ionized gas plasma, are
currently under development. Many of these alternatives are also
incompatible with materials currently sterilized with 12/88. Those that
may be applicable as partial substitutes for 12/88, such as hydrogen
peroxide, are not expected to be commercially available in the near
term.
Alternatives such as radiation and other currently available
technologies should be used wherever applicable, but are not
specifically addressed in this rule due to their limited potential to
be widespread substitutes for 12/88. Additional information on such
alternatives and on specific uses of 12/88 can be found in the
supporting documentation retained in the public docket. The
determinations in this section are based on the risk screen described
in the background document titled ``Risk Screen on the Use of
Substitutes for Class I Ozone-Depleting Substances: Sterilization.''
Responses to comments received on the sterilants sector can be found in
the ``Response to Comment'' document, also found in the public docket.
2. Substitutes for Sterilization
a. Halocarbons. A number of halocarbon substitutes have been
suggested as alternatives to CFC-12 in EtO blends for sterilization.
These include HCFC-123, HCFC-124, HFC-125, HCFC-141b, and HFC-134a and
HFC-227ea. At present, however, only HCFC-124, a blend of HCFCs, and
HFC-227ea have been proposed as near-term candidates. While HCFC-124
has been fully evaluated by the Agency in this rule, final
determinations on the HCFC Blend and HFC-227ea will be made as soon as
complete data is available and the products are approved under FIFRA.
Additional research will be required to determine the suitability of
the other agents in EtO blends.
Many of the proposed halocarbons offer good potential as EtO
diluents. They demonstrate good flame retardation, low ODPs, low GWPs,
low toxicity, materials compatibility, acceptable vapor pressures, and
good blending properties. Mixtures of halocarbons with EtO would most
likely be at ratios similar to 12/88, or with a slightly lower EtO
content. HCFC-124 has been tested with 8.6 percent EtO, for example.
Such properties would make halocarbon blends virtual drop-in
replacements for 12/88 in existing systems. The blends would also be
far less damaging to stratospheric ozone than is 12/88.
b. Carbon dioxide. Carbon dioxide is already in widespread use as a
sterilant in blends with EtO. Previously, the most common blend
contained 10 percent EtO and 90 percent CO2 and was referred to as
``10/90''. However, on October 1, 1993 the Department of Transportation
(DOT) issued regulations on the transport of hazardous materials which
listed EtO/CO2 mixtures as flammable if they contain more than 9
percent EtO. To avoid changing safety and handling procedures,
manufacturers of this blend are changing the formulation of the EtO/
CO2 blend to 8.5/91.5.
While the 8.5/91.5 blend is compatible with most of the materials
now sterilized with 12/88, it must be used at higher operating
pressures than 12/88 systems and hence is not a direct drop-in
replacement for 12/88. Use of CO2 blends requires that the
sterilizing unit be retrofitted to handle higher operating pressures in
order to prevent excessive leakages of EtO from the system.
CO2 and EtO tend to separate while stored in pressurized
containers. Thus, initial discharges from the canisters during use may
contain excessively high amounts of flammable EtO; final discharges
from nearly empty canisters may contain pure CO2 and may not
effectively sterilize equipment. To overcome this problem, single
``unit dose'' canisters have been developed for use in conjunction with
CO2 sterilizers. For safe operation, these canisters must be
connected and disconnected from the sterilizing unit before and after
every use, thereby increasing the risk of accidental exposure. Improved
training procedures will be required with such systems.
c. Pure EtO. Pure EtO systems can also be used in place of current
12/88 sterilizers. By itself, EtO is toxic, carcinogenic, and
flammable. It is also explosive at concentrations above 3 percent in
air. Thus, additional precautions must be taken to limit occupational
exposures and conflagration. Present OSHA standards and proper
engineering controls have demonstrated their ability to provide for
safe operation of such systems. Pure EtO systems are currently used by
many contract sterilizers, large hospitals, and other large users.
3. Listing Decisions
a. Acceptable substitutes. (1) HCFC-124. HCFC-124 is acceptable as
a substitute for CFC-12 in EtO blends. Initial testing in hospital,
industrial, and laboratory settings indicates that an EtO/HCFC-124
blend can serve as a virtual drop-in replacement for 12/88, enabling
users to transition away from CFC-12 while still using their existing
equipment.
Use of HCFC-124 in sterilizers will allow significant reductions in
skin cancer cases and deaths resulting from ozone depletion. HCFC-124
has an ODP of only 0.02. Modeling results indicate that even if HCFC-
124 replaces all current use of CFC-12 in sterilization, resulting skin
cancer deaths in the total US population born before 2030 will total
only 600 more than if a zero ODP substitute were available. In
addition, the low GWP of HCFC-124 ensures that use of the chemical in
sterilizers will have a negligible effect on global warming.
Under Title III of the Clean Air Act Amendments of 1990, the Agency
is required to regulate any of the 189 hazardous air pollutants (HAPs).
Ethylene oxide is a HAP, and the user is alerted to follow all upcoming
regulations concerning the use of ethylene oxide, whether used alone or
in a blend. For example, it is likely in the future that Title III will
require a system that prevents venting of EtO into the atmosphere,
therefore users installing new HCFC-124/EtO systems may choose to take
this into consideration.
(2) Carbon dioxide. Carbon dioxide is acceptable as a substitute
for CFC-12 in EtO blends used for sterilization. Carbon dioxide can
effectively reduce the flammability of EtO and does not deplete
stratospheric ozone. Most CO2 currently used in sterilant mixtures
is the recaptured by-product of other chemical processes, so its
manufacture for use in sterilizers should not increase emissions to the
atmosphere. Carbon dioxide is an asphyxiant in high concentrations, but
engineering controls designed to limit occupational exposures from the
more toxic EtO will also serve to prevent potentially lethal exposures
to CO