98-1783. Federal Motor Vehicle Safety Standards Rear Impact Guards; Rear Impact Protection  

  • [Federal Register Volume 63, Number 16 (Monday, January 26, 1998)]
    [Rules and Regulations]
    [Pages 3654-3662]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 98-1783]
    
    
    
    [[Page 3654]]
    
    -----------------------------------------------------------------------
    
    DEPARTMENT OF TRANSPORTATION
    
    National Highway Traffic Safety Administration
    
    49 CFR Part 571
    
    [Docket NHTSA-98-3342, Notice 1]
    RIN 2127-AA43
    
    
    Federal Motor Vehicle Safety Standards Rear Impact Guards; Rear 
    Impact Protection
    
    AGENCY: National Highway Traffic Safety Administration (NHTSA), 
    Department of Transportation (DOT).
    
    ACTION: Final rule; response to petitions for reconsideration; 
    technical amendment; denial of petition to extend the effective date.
    
    -----------------------------------------------------------------------
    
    SUMMARY: On January 24, 1996, NHTSA published a final rule establishing 
    an equipment standard for underride guards and a vehicle standard which 
    requires the installation of guards meeting the equipment standard on 
    the rear end of heavy trailers and semitrailers. In response to 
    petitions for reconsideration, NHTSA is amending that final rule to: 
    clarify the 100 mm (4 inch) height requirement for the horizontal 
    member of an underride guard, explicitly exclude from having to meet 
    the energy absorption requirements all cargo tank motor vehicles 
    manufactured with rear end protection complying with the high strength 
    requirements of 49 CFR part 178 (to protect hazardous material) that 
    occupies the area specified for NHTSA's underride guard, and increase 
    the acceptable range of force application rates during testing. The 
    agency is also excluding pulpwood trailers from the application of the 
    vehicle standard and denying a petition from the Truck Trailer 
    Manufacturer's Association (TTMA) for an extension of the effective 
    date of the final rule.
    
    DATES: The amendments made by this rule will become effective on 
    January 26, 1998. Petitions for reconsideration of this rule must be 
    received no later than March 12, 1998.
    
    ADDRESSES: Any petitions for reconsideration should refer to the docket 
    number and number of this notice and be submitted in writing to: 
    Administrator, National Highway Traffic Safety Administration, Room 
    5220, 400 Seventh Street, SW, Washington DC, 20590.
    
    FOR FURTHER INFORMATION CONTACT: The following persons at the National 
    Highway Traffic Safety Administration, 400 Seventh Street, SW, 
    Washington, DC, 20590:
    For non-legal issues:
        Dr. George Mouchahoir (Telephone: 202-366-4919) or Mr. Michael 
    Huntley (202-366-0029), Office of Crashworthiness Standards
    For legal issues:
        Mr. Paul Atelsek, Office of the Chief Counsel (202-366-2992), e-
    mail: patelsek@nhtsa.dot.gov
    
    SUPPLEMENTARY INFORMATION:
    
    I. Background
    
        On January 24, 1996, the National Highway Traffic Safety 
    Administration (NHTSA) published a final rule promulgating two new 
    Federal Motor Vehicle Safety Standards (FMVSS) to require upgraded rear 
    impact guards (underride guards) on trailers and semitrailers (61 FR 
    2004).\1\ The first standard (No. 223, Rear impact guards) specifies 
    performance requirements for strength and energy absorption for the 
    underride guards themselves. This standard also contains a 
    configuration requirement that the horizontal cross member of the guard 
    be at least 100 mm (4 inches) high at any point across the guard width.
    ---------------------------------------------------------------------------
    
        \1\ Although both trailers and semitrailers are equally affected 
    by the rule, they will sometimes be referred to simply as 
    ``trailers'' in the remainder of this document.
    ---------------------------------------------------------------------------
    
        As issued in January 1996, the standard requires testing the guards 
    for strength by pushing with a 203 mm by 203 mm (8 inch by 8 inch) 
    force plate at specified points along the horizontal member of the 
    guard. The test continues displacing the force plate at a constant rate 
    of between 1.0 and 1.5 mm/sec (0.04 and 0.06 inches/sec) in a forward 
    direction, as the guard is oriented on the trailer, until the guard 
    resists a specified force, or until 125 mm (5 inches) of displacement 
    occurs. To pass, the guard has to resist the specified force within the 
    first 125 mm (5 inches) of displacement.
        The standard's test for energy absorption is conducted by applying 
    a force in the same way as in the test for strength, but only at one 
    specified test point. The force is recorded at least ten times per 25 
    mm (1 inch) of displacement until the 125 mm (5 inch) displacement is 
    reached and the force plate is completely withdrawn from the guard. The 
    guard energy absorption is calculated from a force vs. deflection 
    diagram plotted using the recorded measurements. Only plastic 
    deformation (permanent deformation) is counted toward meeting the 
    required amount of energy absorption--elastic rebound of the guard does 
    not count.
        The second standard (No. 224, Rear impact protection) requires most 
    new trailers and semitrailers with a Gross Vehicle Weight Rating of at 
    least 4,536 kg (10,000 pounds) to be equipped with a rear impact guard 
    meeting the requirements of the equipment standard. This standard also 
    specifies requirements for the location of the horizontal member of the 
    guard relative to the rear end of the trailer or semitrailer, including 
    a requirement that the rearmost surface of the member be located no 
    more than 305 mm (12 inches) forward of the trailer's rear extremity. 
    Certain types of trailers, including pole trailers and ``wheels-back'' 
    vehicles, are excluded from the application of this rule.
        The January 1996 final rule on truck underride protection specified 
    an effective date of January 26, 1998 and a March 11, 1996 deadline for 
    receiving petitions for reconsideration on this rule.
    
    II. Petitions for Reconsideration
    
        NHTSA received five petitions for reconsideration of the final rule 
    from companies in the trailer and semitrailer equipment and 
    manufacturing industries. In addition, one letter was received from an 
    insurance group.
        The Insurance Institute for Highway Safety (IIHS) did not request 
    any change to the rule. IIHS's letter sought to clarify what IIHS 
    considered a misunderstanding (i.e., undercounting) on NHTSA's part 
    regarding the potential number of lives saved as a result of the final 
    rule. IIHS stated that this clarification was needed if the agency is 
    to decide on future rulemaking actions on rear underride for single-
    unit trucks or side underride for large trucks. NHTSA has met with IIHS 
    staff to discuss their views on how best to estimate potential lives 
    saved, and made adjustments in its data collection efforts to improve 
    the quality of its data on underride crashes. The letter was not 
    labeled as a petition and will not be addressed further.
        One of the petitioners was Rite-Hite Corporation which manufactures 
    ``dock locks,'' safety restraint equipment that is mounted on loading 
    docks to secure trailers to the docks during loading and unloading. 
    Rite-Hite requested that the agency modify the configuration and 
    strength specifications of the guard to be compatible with its dock 
    locks. It stated that the requirements of the final rule directly 
    affect the ability of its dock locks to safely engage and hold trailers 
    to the loading docks. The Rite-Hite loading dock device uses a hook 
    that wraps around and over the rear protection guard to help prevent 
    guards from riding up and over the restraining barriers, and to help 
    prevent incidents
    
    [[Page 3655]]
    
    that can result from trailer tip-over and landing gear collapse. Rite-
    Hite estimates that 100,000 of these dock locks currently exist.
        Rite-Hite asked NHTSA to comment on the role of its final rule with 
    regard to limiting civil tort liability. Rite-Hite states that some 
    vehicle manufacturers and others in the industry consider the final 
    rule to be the sole factor to be considered in designing underride 
    guards. It requested that the agency clarify that compliance with the 
    final rule does not by itself insulate any manufacturer of rear impact 
    guards from all civil tort liability. It also urged NHTSA to state that 
    guard and trailer manufacturers must also take into account other 
    safety issues, such as loading dock uses of rear impact guards, in 
    making appropriate and reasonable design choices that are consistent 
    with the final rule.
        Rite-Hite also petitioned for several changes to specific 
    provisions of the final rule. It requested NHTSA to change the minimum 
    cross sectional vertical height requirement in S5.1 of Standard No. 
    223, which currently specifies that ``[t]he horizontal member of each 
    guard shall have a cross sectional vertical height of at least 100 mm 
    [4 inches] at any point across the guard width'' (emphasis added). Some 
    manufacturers are manufacturing guards with horizontal members that are 
    100 mm (4 inches) high on both the front and back sides of the 
    horizontal member. Rite-Hite is concerned because the vehicle restraint 
    may not engage properly in certain circumstances (e.g., abnormally high 
    horizontal member, guard located forward of the rear extremity, poor 
    alignment of the vehicle with the dock, and bumpers affixed to the 
    horizontal member). It is also concerned that the restraint's warning 
    light may not indicate the failure to engage without being modified.
        To address this potential problem, Rite-Hite petitioned NHTSA to 
    either: (1) Specify 4 inches as the maximum height, (2) change the 
    regulatory language to restrict the height specification to the rear-
    facing side of the horizontal member, or (3) insert an interpretation 
    that the existing language applies only to the rear-facing side of the 
    horizontal member and an advisory that some vehicle restraint 
    manufacturers recommend forward-facing surfaces be about 1.25 inches 
    high.
        Rite-Hite also requested NHTSA to modify S5.2.1 of Standard No. 223 
    to increase the minimum guard strength at location P2 (in the center of 
    the guard, where Rite-Hite's dock locks attach). It stated that, 
    because many vehicle restraints will provide 2-3 times more holding 
    power than the guard strength requirement of the rule (50,000 N, or 
    11,240 lb), guard strength is not sufficient to withstand the forces 
    encountered during premature trailer pull-out from loading docks. 
    Therefore, Rite-Hite petitioned the agency to increase the minimum 
    force at test point P2 (where dock locks typically attach) to 
    approximately 150,000 N (33,370 lb).
        Rite-Hite requested that the test procedures of S6.6 of Standard 
    No. 223 be amended so the guard would have to meet similar strength 
    requirements when pushed in a rearward direction (i.e., in the opposite 
    direction from the striking vehicle) as it has to meet when it is 
    pushed forward.
        Rite-Hite requested that NHTSA delete the exclusion from Standard 
    No. 224 for ``wheels-back vehicles.'' These are vehicles on which the 
    rear tires are fixed at a position within 305 mm (12 inches) of the 
    rear extremity of the trailer. Rite-Hite suggested that there will be 
    an increase of loading dock incidents without an underride guard to 
    secure the rear of the trailer to the dock. It also argued that wheels-
    back vehicles with wide-spaced single tires and no underride guard 
    would increase the chance of passenger compartment intrusion, 
    presumably by allowing the striking vehicle to penetrate between the 
    tires.
        Rite-Hite also requested that the horizontal member of the guard, 
    and of hydraulic guards in particular, not be permitted, as it 
    currently is, to extend rearward of the rear extremity of the vehicle. 
    The company is concerned about damage to the dock locks, the dock 
    walls, the underride guard itself, and with the dock lock not properly 
    engaging. It is also concerned that rear-extending guards will prevent 
    the trailer from backing up flush with the dock, creating a gap between 
    the trailer bed and the loading dock, even with a dock lock engaged. 
    Rite-Hite states that this gap could cause loss of ``lip purchase'' of 
    loading dock levelers on the bed of the trailer, and personal injury to 
    loading dock employees. Rite-Hite also asked that NHTSA clarify that 
    hydraulic guards must meet the dimensional and guard strength 
    requirements for non-hydraulic guards.
        To ensure adequate engagement with dock locks, Rite-Hite also 
    requested that the horizontal member be restricted to a position no 
    more than 2 inches forward of the trailer rear extremity, rather than 
    the currently permitted 305 mm (12 inches).
        Rite Hite wants the agency to specify a minimum horizontal guard 
    member height of 457 (18 inches) above the ground. It is concerned that 
    lower heights might not adequately engage the dock locks and might 
    increase the chances of the guards being damaged by road surfaces and 
    falling off.
        Finally, Rite Hite requested NHTSA to prohibit a sloped surface on 
    the forward side of the rear impact guard and require a vertical 
    surface there instead. Rite Hite states that the sloping surface will 
    depress all kinds of vehicle restraints designed to hold on to the 
    underride guard, thus causing disengagement.
        TTMA petitioned the agency to define ``cargo tank motor vehicle'' 
    and make it clear that any vehicle so constructed would not have to 
    meet the energy absorption requirements of the rule. It stated that the 
    ``present definition of a special purpose vehicle defines a cargo tank 
    motor vehicle excluded by Standard No. 224 by its operational 
    characteristics, namely, hazardous material held in transit, instead of 
    by its construction characteristics.'' It noted that cargo tank motor 
    vehicles are required by 49 CFR 178.345-8(d) 2 to have very 
    strong rear end protection to protect the cargo tank and its piping in 
    the event that another vehicle impacts it from the rear. TTMA argued 
    that a manufacturer cannot design a guard to meet both the extreme 
    rigidity requirements of 49 CFR 178.345-8(d) and the energy absorption 
    (yielding) requirements of S5.2.2 of Standard No. 223.
    ---------------------------------------------------------------------------
    
        \2\ These rules are administered by the Department of 
    Transportation's Research and Special Programs Administration 
    (RSPA).
    ---------------------------------------------------------------------------
    
        Great Dane Trailers, Inc. (Great Dane) petitioned the agency to 
    increase the permissible range of force application during the strength 
    and energy absorption tests. It stated that the current requirement to 
    maintain a constant rate of between 1 mm and 1.5 mm per second (60 mm 
    and 90 mm per minute) ``may require expensive and sophisticated 
    equipment'' and that the rate of displacement is not a significant 
    indicator of the performance of the guard. Great Dane suggested 
    changing the requirement to specify a rate that ``averages not less 
    than 1 mm and not more than 25 mm per second over each 25 mm of 
    displacement.''
        Great Dane also requested that the minimum energy absorption test 
    be amended to double the displacement of the horizontal member of the 
    guard. Great Dane stated that its current guards do not respond by 
    plastic deformation until 75 mm (3 inches) of displacement has been 
    achieved, and that stopping the test at 125 mm (5 inches) of 
    displacement, as currently specified,
    
    [[Page 3656]]
    
    will require it to weaken the guards to meet the requirements. Great 
    Dane petitioned to displace the guard to 250 mm (10 inches), thus 
    ensuring more plastic deformation of the guards and increasing the 
    energy absorption to 2-3 times the desired minimum. Great Dane 
    subsequently forwarded test data that it believed supported its 
    request.
        STRICK Corporation (STRICK), a trailer manufacturer, also expressed 
    concern over the need to purchase expensive precision testing equipment 
    to replace their current devices. In its testing, STRICK found it 
    ``impossible to determine the exact displacement for each and every 
    second over the time of the test.'' STRICK petitioned to change the 
    requirement from maintaining a constant rate of displacement between 1 
    mm and 1.5 mm per second band to a requirement of ``displacement rate 
    of the force is approximately constant over a time of 1 to 5 minutes''. 
    STRICK is basically requesting a slower force application (i.e., more 
    time, which would be required with a slower pump) to reach the 125 mm 
    (5 inch) required displacement. STRICK also argued that the 
    ``displacement requirement'' in the final rule was inserted without 
    adequate notice and represents a major change from the proposal.
        Finally, James King & Co. (King) petitioned the agency to amend the 
    rule to require that rear truck underride guards protect from damage 
    the reflective conspicuity markings required by Standard No. 108, 
    Lamps, reflective devices, and associated equipment. King has observed 
    that few manufacturers have provided the protective measures that NHTSA 
    had suggested that manufacturers could take (e.g., mounting the 
    reflective material in a steel channel or placing small metal beads 
    above and below the reflective stripe). As a result, King believes 
    that, contrary to the agency's assumptions, the majority of markings 
    are damaged after a short time in use. King did not suggest a 
    particular solution.
    
    III. Response to Petitions
    
        NHTSA agrees with Rite Hite that mere compliance with NHTSA's 
    vehicle safety standards does not insulate any guard or trailer 
    manufacturer from civil liability. 49 U.S.C. 30103(e) explicitly states 
    ``[c]ompliance with a motor vehicle safety standard * * * does not 
    exempt a person from liability at common law.'' NHTSA's standards are 
    minimum standards that specify a floor, not a ceiling, for performance. 
    They are intended to allow manufacturers flexibility in the selection 
    of means of compliance. Designers of underride guards and trailer 
    manufacturers that install them are free to consider the non-highway 
    safety implications of their designs, including the functioning of the 
    guards with existing dock locks.
        The agency also agrees with Rite Hite that the standard currently 
    does not specify where, within its longitudinal cross section, the 
    horizontal member of the guard must have a vertical height of 100 mm (4 
    inches). Some guard manufacturers are apparently misinterpreting that 
    provision as requiring a 100 mm (4 inch) height across the entire 
    longitudinal cross section, from front to back.
        However, this reading is more design restrictive than the agency 
    intended, and is not necessary for safety purposes. The 100 mm (4 inch) 
    minimum height is intended to assure adequate engagement with and 
    crushing of the frontal vehicle structure by preventing ``knife-
    edging'' by a guard that is too thin. In the final rule, the agency 
    concluded that this objective would be achieved by any guard with a 100 
    mm (4 inch) cross sectional height that is forward of the rear 
    extremity by not more than 305 mm (12 inches). The requirement in S5.1 
    of Standard No. 223 for a cross sectional vertical height of 100 mm (4 
    inches) does not need to be met in any specific transverse vertical 
    plane. The important relationship is the distance between the trailer 
    rear extremity and the forwardmost point at which at least 100 mm (4 
    inches) of guard height would be engaged by a colliding vehicle.
        Given the preceding statement, Rite Hite's proposed changes to the 
    regulation would unnecessarily restrict guard configuration. For 
    example, it would be too design restrictive to require that the 100 mm 
    (4 inch) cross section be measured at the rearmost point on the 
    horizontal member, as Rite Hite suggests. This would be equivalent to 
    saying that the guard must have a 100 mm (4 inch) vertical face at the 
    rear. Although this design is common and probably the best at assuring 
    immediate engagement, some manufacturers might prefer to use tubular 
    designs for the horizontal member. Tubular designs would not comply 
    with Rite Hite's suggested amendment, because the rearmost surface 
    would be a line rather than a 100 mm (4 inch) high plane. Nevertheless, 
    a tubular horizontal member would assure adequate engagement. It would 
    also be too design restrictive to require that the cross section be 
    vertical. Some shapes without vertical transverse cross sections of the 
    required height might provide superior engagement or crash dynamics. 
    For example, some guards might be shaped with sloped rear surfaces to 
    account for the guard pivoting during a crash. As long as the 
    horizontal projection of the horizontal member on a vertical plane 
    presents a 4-inch high profile, then the desired objective will 
    generally be achieved.
        The agency is concerned about the development of certain untested 
    guard shapes, however. As previously stated, most current guard designs 
    have a vertical face with a 100 mm (4 inch) minimum height at the first 
    point of contact for an underriding vehicle. This configuration 
    provided good protection for passenger vehicle occupants in the NHTSA's 
    tests. The non-design-restrictive requirements should not imply 
    encouragement of the development of horizontal members with convex 
    cross sections at the rear. For example, some manufacturers might want 
    to design guards with angular, or lens-shaped, cross sections to 
    achieve better aerodynamic properties. The quality of engagement of 
    such guard shapes with the underriding vehicle has not been evaluated.
        The agency is also concerned that portions of the horizontal member 
    necessary for adequate engagement might be located more than 305 mm (12 
    inches) forward of the vehicle's rear extremity. For example, on a 
    guard with a 100 mm (4 inch) high tubular horizontal cross member whose 
    rearmost surface is located the full 305 mm (12 inches) forward of the 
    trailer rear extremity, a full engagement of the guard's horizontal 
    member will not occur until it has advanced 305 mm (12 inches), plus 
    the 25 mm (2-inch) radius of the tube. In some cases, engagement might 
    come too late to prevent passenger compartment intrusion. The purpose 
    of the requirement in S5.1.3 of Standard No. 224 regarding the location 
    of the guard's rearmost surface is to assure that full engagement is 
    achieved as early in the crash event as possible, but in any case 
    before the passenger vehicle has penetrated more than 305 mm (12 
    inches) under the trailer. Therefore, NHTSA is amending S5.1 to require 
    that the vertical height requirement be met by the horizontally 
    projected height of the horizontal member of the guard on a transverse 
    vertical plane, and that the guard manufacturer's installation 
    instructions or procedures specify that the forwardmost part of the 
    horizontal member necessary to meet this requirement must be located no 
    more than 305 mm (12 inches) forward of the rear extremity of the 
    vehicle.
        The agency denies Rite-Hite's request to eliminate the wheels back 
    vehicle exclusion in S3 of Standard No. 224, as it applies to the 
    single-tire wheels back
    
    [[Page 3657]]
    
    trailers, because the agency does not have enough information on these 
    vehicles at this time. However, NHTSA is concerned with the possibility 
    that some smaller passenger vehicles could fit between the tires of 
    these trailers. In this case, the passenger vehicle might advance past 
    the rear extremity of the trailer by 305 mm (12 inches) before reaching 
    the rearmost point on the rear tires, and then advance an additional 
    distance approximately equivalent to the radius of these large tires, 
    before contacting the axle. This distance, combined with the subsequent 
    crush of the front end of the passenger vehicle, might allow passenger 
    compartment intrusion. The agency appreciates Rite-Hite's concern about 
    the lack of guards leading to an inability to engage dock locks. NHTSA 
    notes that the rule does not prohibit ``partial'' guards in between the 
    wheels of wheels back trailers. Manufacturers of excluded vehicles may 
    install partial or full underride guards if they consider it essential 
    to engage loading dock restraint devices.
        NHTSA requested data from TTMA on trailers and semitrailers with 
    single rear tires. TTMA was able to confirm that these vehicles exist 
    and provided a picture of one, but had no further information on hand. 
    The agency also has little information on these vehicles, their tire-
    to-tire spacing, or their uses. Therefore, NHTSA currently has 
    insufficient information to determine whether the wheels back exclusion 
    should continue to apply to these vehicles or whether partial guards 
    might be appropriate. The agency is planning to begin collecting data 
    within the National Automotive Sampling System starting in the summer 
    of 1998 to define the scope of this potential problem. When NHTSA has 
    gathered the appropriate information, it will consider whether a 
    rulemaking is warranted to address the issue of single-tire wheels back 
    vehicles.
        NHTSA denies the remainder of Rite-Hite's requests. These requests 
    appear to be intended to ensure that guards are required to be 
    compatible withRite-Hite's particular dock lock design. Although NHTSA 
    is also interested in ensuring the safety of loading dock workers, the 
    requested changes all tend to restrict underride guard design and 
    reduce manufacturer flexibility that NHTSA considers essential to the 
    practicability of the rule. Not all trailers and semitrailers use 
    loading docks. Further, NHTSA understands that there are dock lock 
    designs that do not require underride guard design restrictions. If 
    trucking companies want maximum compatibility with all types of dock 
    locks, including Rite-Hite's, there is nothing in NHTSA's rule to 
    prevent them from ordering, or to prevent manufacturers from designing, 
    underride guards exactly as Rite-Hite suggests.
        For the same reason that NHTSA is granting Rite-Hite's request to 
    clarify that the cross-sectional vertical height requirement need not 
    be met at the forward-facing surface of the horizontal member of the 
    guard, the agency denies Rite-Hite's request to prohibit sloping 
    surfaces or to require a maximum height of 1.25 inches on that surface. 
    Because there are no vehicle safety benefits related to the shape and 
    size of the forward-facing surface, it would be unnecessarily design 
    restrictive to impose certain geometries or height requirements on that 
    surface. Regardless of the geometry, Rite-Hite's petition indicates 
    that manufacturers can adapt the forward-facing surface to be 
    compatible with dock locks by attaching a \3/4\ inch metal bar to the 
    bottom of the forward-facing surface. Standard No. 223 does not 
    prohibit this approach.
        The agency also denies Rite-Hite's request to modify S5.2.1 of 
    Standard No. 223 to require the guard's strength at location P2 be 
    increased to approximately 150,000 N (33,370 lb). A guard strong enough 
    to withstand the forces encountered when drivers attempt to pull out 
    while still locked to the dock is not necessary for crashworthiness. 
    This request pertains to the strength of the guard in the opposite 
    direction (i.e., rearward) from the one specified in the final rule. 
    The rule specifies a minimum strength to withstand forces in the 
    forward direction, such as would result from an underriding vehicle. 
    The rule does not regulate the requested aspect of performance, and 
    regulating it would not serve the purpose of the rule. For the same 
    reasons, the agency denies Rite-Hite's request that S6.6 of Standard 
    No. 223 be amended so there is a rearward direction force application 
    test in addition to the specified forward direction test. NHTSA again 
    notes that there is nothing in the rule to prevent guard manufacturers 
    from designing guards as Rite-Hite suggests, with 150,000 N (33,370 lb) 
    strength in the rearward direction.
        The agency denies Rite-Hite's request to amend the language of 
    S5.1.3 of Standard No. 224 to prohibit the horizontal member of the 
    guard from extending rearward of the transverse vertical plane tangent 
    to the rear extremity of the vehicle. NHTSA expects that manufacturers 
    will not design, and trucking companies will not order, underride 
    guards for uses that will damage loading docks, dock locks, loading 
    dock levelers, and the guards themselves. NHTSA is aware of some 
    trailer and semitrailer applications for which a guard extending 
    rearward of the trailer rear extremity is useful. These applications do 
    not use loading docks. In addition, rearward mounting is useful in 
    preventing underride and passenger compartment intrusion by the rear of 
    the passenger vehicle. The agency does not want to prohibit these 
    benefits for the sake of regulating the unlikely occurrence of 
    excessively rearward guard location. For the same reasons, Rite-Hite's 
    request that ``hydraulic guards not hinge rearward of the transverse 
    vertical plane tangent to the rear extremity of the vehicle'' is 
    denied. NHTSA notes that hydraulic guards are already required to meet 
    the same dimensional and strength requirements as non-hydraulic guards.
        NHTSA denies Rite-Hite's request to prohibit positioning the guard 
    more than 2 inches forward of the trailer rear extremity. This would 
    eliminate nearly all of the fore-aft flexibility that the agency 
    believes that manufacturers need in positioning their guards, merely 
    because a distance more than 50 mm (2 inches) will not be compatible 
    with Rite-Hite's restraint. NHTSA emphasizes that the final rule 
    specified mounting the guard within a range of 305 mm (12 inches) or 
    less, and as close to the rear extremity as practical. This requirement 
    is probably sufficient to ensure that the vast majority of trailers and 
    semitrailers are compatible with Rite-Hite's needs. Nearly all guards 
    are currently being mounted flush with the trailer rear extremity. 
    NHTSA does not believe that the final rule will change that practice. 
    If a certain kind of guard is needed for safely docking with dock 
    locks, trucking companies will presumably specify such guards in their 
    orders for new vehicles. This would be an additional factor making 
    change unlikely.
        NHTSA denies Rite-Hite's request that S5.1.2 of Standard No. 224 be 
    amended to prohibit mounting guards with the horizontal member lower 
    than 457 mm (18 inches) from the ground. The possibility of guard 
    damage, along with the extensive comments received from the public on 
    ground clearance, were discussed at length in the preamble of the 
    January 1996 final rule. The comments indicated that it would be 
    impractical to mount the guards much lower than the maximum clearance 
    of 560 mm (22 inches) anyway. The agency does not expect vehicle 
    manufacturers to mount guards at heights at which the guards or the 
    vehicles would be damaged due to operational restrictions (e.g., 
    railroad crossings). In addition,
    
    [[Page 3658]]
    
    higher costs of lower guards and the difficulty of meeting the strength 
    requirements at lower heights are additional factors that will keep 
    most manufacturers from producing guards that are lower than the 
    maximum height. Therefore, setting a minimum clearance requirement is 
    unnecessary. Assuming manufacturers did want to produce them for uses 
    with fewer operational restrictions, lower guards would be safer in a 
    crash. NHTSA has no evidence that loose guards are falling off and 
    creating a highway hazard. Regulation is not necessary in this area.
        The agency agrees with TTMA that the current language of Standard 
    No. 224's definition of ``special purpose vehicle'' might be 
    interpreted to exclude cargo tank motor vehicles due to their 
    operational use, rather than their construction characteristics. The 
    rule defines special purpose vehicles as having ``work-performing 
    equipment (including any pipe equipment that would hold hazardous 
    materials in transit * * *) that, while the vehicle is in transit, 
    resides in or moves through the area that could be occupied by the 
    horizontal member of the rear impact guard * * *'' The phrase ``that 
    would hold hazardous materials'' might, in the case of a cargo tank 
    motor vehicle, imply that the exclusion depends on the intentions or 
    subsequent actions of the purchaser of the cargo tank motor vehicle. 
    Although manufacturers generally know that trailer owners willing to 
    pay for a trailer certified to RSPA's standards are planning to 
    transport hazardous materials, the manufacturer of a cargo tank motor 
    vehicle should not be charged with the responsibility for determining 
    what its use will be after it is out of the manufacturer's control.
        Therefore, as the TTMA requested, the agency is deleting the phrase 
    in the definition of special purpose vehicle that explicitly recognized 
    pipe equipment that would carry hazardous material as work performing 
    equipment. Piping that carries hazardous materials would still be 
    considered work-performing equipment, as would any other piping that 
    needs to occupy the area of the guard while the vehicle is in transit. 
    However, piping carrying hazardous materials would probably not be 
    located in such an exposed location, because RSPA's regulations (e.g., 
    178.345-8, 178.338-10) generally require that such piping be protected 
    by RSPA's vehicle rear end protection device or rear 
    bumper.3
    ---------------------------------------------------------------------------
    
        \3\ Both terms are used to refer to underride guard-type devices 
    in RSPA's regulation. ``Rear-end protection device'' is used in 49 
    CFR 178.345, while ``rear bumper'' is used in 49 CFR 178.337 and 
    178.338. These terms are used below when discussing cargo tank motor 
    vehicles, both to avoid confusion and to emphasize the different 
    primary purpose they serve--protecting hazardous material in the 
    tank, rather than protecting colliding vehicle occupants with crash 
    protection.
    ---------------------------------------------------------------------------
    
        The standard still needs to be revised to prevent conflict with 
    RSPA's rule. The high strength requirements for cargo tank motor 
    vehicle rear end protection devices or rear bumpers in RSPA's 
    regulations are incompatible with NHTSA's energy absorption 
    requirement. NHTSA intended to apply only the configuration and 
    strength requirements, but not the energy absorption requirements, to 
    vehicles meeting RSPA's requirements with rear-end protection device or 
    rear bumpers in the area specified by NHTSA for the underride guard. 
    NHTSA's strength requirements are far lower than RSPA's, so meeting 
    NHTSA's strength requirements will not be a problem for hazardous 
    materials cargo tank motor vehicles. The agency stated in the final 
    rule (at 61 FR 2023) that:
    
        RSPA's rule for underride guards on hazardous materials tankers 
    (49 CFR Part 178.345-8) is generally compatible with this rule, and 
    this rule applies to hazardous materials tankers. However, to 
    prevent any confusion as to the relationship between RSPA's rule and 
    NHTSA's rule, this rule explicitly recognizes that piping that 
    carries hazardous materials while in transit needs the special 
    protection that is provided by RSPA's rule.
    
        Explicitly recognizing vehicles with the pipe equipment in the area 
    of the guard as special purpose vehicles did not capture within the 
    exclusion all the vehicles that must be excluded. Any tanker built to 
    conform to RSPA's regulations with a rear-end protection device or rear 
    bumper in the area specified for NHTSA's underride guard cannot 
    practically comply with NHTSA's energy absorption requirement, 
    regardless of whether it has pipe equipment in the area of the guard or 
    whether the pipe equipment passes through the area where the guard 
    could be located.
        Therefore, NHTSA is adding a paragraph to the Application section 
    of Standard No. 224 explicitly excluding all cargo tank motor vehicles 
    built to RSPA's standards, including insulated cargo tanks and tanks 
    that carry compressed gases, from the requirement to meet the energy 
    absorption requirements of S5.2.2 of Standard No. 223, if the rear-end 
    protection device or rear bumper is in the area specified for NHTSA's 
    underride guard.
        The agency is stating the exclusion more broadly than the TTMA 
    suggested. The TTMA petitioned to add a definition for a cargo tank 
    motor vehicle, which referenced some (but not all) of RSPA's tanker 
    specifications. In NHTSA's view, the benefits of energy absorption for 
    the striking vehicle are outweighed by the additional danger to that 
    and other vehicles from spillage of hazardous cargo, so that all 
    tankers that might be carrying hazardous materials should be excluded 
    from the energy absorption requirement. RSPA occasionally adds cargo 
    tank motor vehicle specifications and may also add vehicle rear end 
    protection device or rear bumper specifications to its regulations. If 
    the rule referenced RSPA's regulations for every specific tanker and 
    guard type, every change to the RSPA regulations would necessitate a 
    corresponding change to Standard No. 224's application section. Due to 
    the difficulty of coordinating interagency rulemakings and effective 
    dates, the rule simply references the part of RSPA's regulations that 
    specifies cargo tank motor vehicles and rear end protection devices or 
    rear bumper requirements, and excludes from the energy absorption 
    requirements of this rule all cargo tank motor vehicles that comply 
    with that part and have a rear end protection device or rear bumper in 
    the area specified for the underride guard. Any future changes by RSPA 
    to its tanker guard requirements will likely be made to this part, and 
    would be automatically incorporated by reference in Standard No 224.
        The agency notes that this exclusion from the energy absorption 
    requirements for RSPA guards on cargo tank motor vehicles applies only 
    when the RSPA rear end protection device or rear bumper occupies the 
    space specified for the horizontal member of the NHTSA guard and meets 
    the configuration and strength requirements specified for the NHTSA 
    guard. For example, many cargo tank motor vehicles have a rear end 
    protection device or rear bumper located several feet off the ground. 
    The guards on these trailers are not excluded from NHTSA's energy 
    absorption requirement of Standard No. 223.
        The requests of Great Dane Trailers and STRICK Corporation 
    regarding the rate of force application in the tests for strength and 
    energy absorption can be treated together. NHTSA agrees that changing 
    the displacement rate requirements in S6.6(a) of Standard No. 223 to 
    accommodate concerns about the practicability of the test procedure 
    would not affect the intent of the rule or the determination of the 
    guard's strength. The objective of the requirement is to assure that 
    the guard
    
    [[Page 3659]]
    
    is being tested quasi-statically because the specified test procedure 
    is not a dynamic test.
        The specified rate of displacement during force application (1.0 to 
    1.5 mm/s) may be narrow and too restrictive to accommodate slow-pumping 
    force application equipment. NHTSA accepts Great Dane's and STRICK's 
    assertions that new and expensive equipment would be required for those 
    companies to achieve this rate. More powerful hydraulic pumps are 
    required to achieve higher rates of displacement during the test, 
    especially with stronger guards. The agency has no information on how 
    powerful STRICK's pumps are, but NHTSA chose the quasi-static test 
    procedure at least in part to accommodate small trailer manufacturers 
    that presumably have less sophisticated equipment. For steel, the most 
    common guard material, the rate of force application, within reasonable 
    bounds, should not make a significant difference in the test results.
        For reasons that seem inconsistent with the basis for their 
    requests, both companies asked for an increase in the permitted 
    displacement rate. The agency denies these requests. Great Dane 
    requested an increase in the upper limit of the specified range from 
    1.5 mm/sec to 25 mm/sec, and STRICK requested an increase to 2.08 mm/
    sec. At a displacement rate of 25 mm/sec, a 125 mm (5-inch) test 
    displacement would be completed in a very short duration of about 5 
    seconds. This is a very fast force application and conflicts with the 
    intent of the rule to specify a quasi-static, not a dynamic, test 
    procedure. Moreover, Great Dane's proposed rate of 25 mm/s would 
    require high precision and sophisticated computer-controlled test 
    equipment as well as powerful and efficient pumps--potentially 
    representing upgraded equipment that both companies state they want to 
    avoid. The agency notes that NHTSA's Vehicle Research and Test Center 
    (VRTC) successfully performed its testing program for the subject final 
    rule using manually-controlled test equipment with no special 
    instrumentation. Less sophisticated equipment with lower pump capacity 
    requires more, not less, test duration. The current upper limit on the 
    rate of displacement during force application of 1.5 mm/sec is being 
    retained. This should not present a problem for Great Dane or STRICK, 
    because lower displacement rates can also be selected on more capable 
    equipment.
        Regarding the lower bound for displacement rate, the agency 
    believes that 6.3 minutes is adequate time to achieve the required 
    displacement without the need for sophisticated control equipment and 
    powerful pumps. No petitioner has requested a longer period and, unless 
    the agency is presented with evidence of a problem with this rate, it 
    will consider longer periods as unnecessarily prolonging certification 
    and compliance testing. As explained earlier, reasonably slower 
    displacement rates will probably not make a significant difference in 
    test results anyway. Therefore, NHTSA is granting part of STRICK's 
    request and widening the specified displacement rate range to allow 
    displacement rates as low as 0.33 mm/sec. Testing at this rate will 
    allow a 125 mm (5 inch) test displacement to be achieved in a period of 
    about six minutes.
        The range of force displacement rate will now be specified in 
    centimeters and minutes rather than in millimeters and seconds, i.e., 
    as 2.0 cm/minute to 9.0 cm/minute. This range replaces the currently 
    specified range of 1.0 to 1.5 mm/sec (6.0 to 9.0 cm/minute). The larger 
    distance per time period is easier for most people to visualize. It is 
    NHTSA's understanding that the displacement rate on most modern test 
    equipment (and on all the equipment NHTSA would use for compliance 
    testing) is controlled by a computer with a feedback system capable of 
    quickly and automatically adjusting the displacement rate. However, for 
    purposes of certification testing on non-computer controlled equipment, 
    precise adjustment is impractical. Specifying the distance on a per-
    minute time scale will allow for practical adjustments of the rate of 
    displacement within each minute. This change would result in a more 
    practical test procedure and should not compromise the performance 
    requirements of the rule. The language of section 6.6(a) of Standard 
    No. 223 is changed accordingly.
        The word ``constant'' has been eliminated from the test procedure 
    as a modifier of the displacement rate. As Great Dane pointed out, the 
    term ``constant'' is confusing because it is so absolute. The concept 
    of tolerance, for purposes of compliance testing, has been introduced 
    as explained below.
        Normally, when NHTSA specifies a range in the test conditions of 
    its standards, the equipment being tested is expected to meet the 
    specified performance requirements when testing at any point within the 
    range. In this case, the agency is allowing a broader range of 
    displacement rates (with a significantly slower rate of displacement at 
    the lower end of the range) than was allowed originally, to accommodate 
    the manufacturers' desire to conduct certification testing with their 
    existing equipment. Applying the usual procedure, NHTSA could test and 
    expect compliance at any rate within the wider displacement rate range. 
    However, this would have the effect of making it more, not less, 
    difficult for manufacturers to certify compliance, because the same 
    requirements would have to be met under a wider range of conditions. 
    The agency notes again that tests within the new range of displacement 
    rates should yield similar results to tests within the old range 
    because the performance of most current guard materials is not rate 
    sensitive even over this broader range of load application rates.
        Because merely granting the petitioner's request would not achieve 
    the petitioner's objective of making certification testing easier, 
    NHTSA will allow the guard manufacturer to designate the displacement 
    rate, within the range of 2.0 to 9.0 cm/minute, on which it based its 
    certification. If compliance tests are conducted by the agency, the 
    manufacturer's designated rate, plus or minus 10 percent, will be used. 
    The practical effect of this is that the guard must comply at the 
    designated rate as well as any rate within 10 percent above or below 
    that rate. As noted above, having to maintain a ``constant'' designated 
    displacement rate would make it practically impossible for the agency 
    to conduct compliance testing. For the same reason, NHTSA will not 
    attempt to duplicate during compliance testing the deflection/time 
    curve that the manufacturer experienced during certification testing. 
    As long as the agency stays within the 10 percent tolerance during the 
    entire test, the compliance test will be valid. If the manufacturer, 
    for whatever reason, does not designate a displacement rate, NHTSA may 
    pick any rate within the specified range.
        NHTSA denies Great Dane's request to amend the energy requirement 
    to require twice as much displacement for the purpose of the energy 
    absorption test. The petitioner stated that the ``current limit of 125 
    mm will require guards which are weaker (less stiffness) be installed 
    merely to meet the energy absorption level of 5650 J.'' This amendment 
    would have the effect of allowing stiffer guards by displacing the 
    guard 250 mm (10 inches) instead of 125 mm (5 inches) before measuring 
    to determine whether the guard absorbed the minimum 5,650 joules (4,170 
    ft-lbs) of energy. The greater displacement would make it easier for 
    the required plastic deformation of the guard to occur. However, the 
    point of the energy absorption requirement is to prevent
    
    [[Page 3660]]
    
    overly stiff guards. It would enhance crash safety if manufacturers 
    weaken guards that are too stiff, because this will allow a softer 
    ``crash pulse'' for the colliding passenger vehicle by ``riding down'' 
    the speed over a short distance during the crash.
        Moreover, NHTSA notes that the data that Great Dane submitted in 
    support of this request does not indicate that any change is needed in 
    the standard. The test data provided by Great Dane show that the guards 
    they tested displayed more than twice the required energy absorption 
    when tested according to the current requirement of 125 mm (5 inches) 
    of displacement.
        Finally, the agency denies King's request to amend the final rule 
    to include requirements that rear underride guards protect conspicuity 
    markings from damage. The Federal Highway Administration (FHWA) has 
    jurisdiction over trailers after the first sale for purposes other than 
    resale and regulates the maintenance of required safety equipment. 
    Section 393.11 of the Federal Motor Carrier Safety Regulations (FMCSRs) 
    requires that commercial motor vehicles meet the requirements of 
    Standard No. 108 in effect at the time the vehicle was manufactured (49 
    CFR 393.11). Since December 1, 1993, Standard No. 108 has required new 
    trailers to meet conspicuity requirements. Accordingly, motor carriers 
    are currently required under FHWA regulations to maintain the 
    conspicuity treatments on these trailers. This includes maintaining the 
    conspicuity treatment on the horizontal member of the underride guard.
        On April 14, 1997, FHWA issued an NPRM (62 FR 18170) that would 
    amend the FMCSRs at 49 CFR 393.11, Lighting Devices and Reflectors, to 
    make certain that all motor carriers operating trailers subject to the 
    FMCSRs are aware of their responsibility to maintain the conspicuity 
    treatments in all locations required by Standard No. 108. However, FHWA 
    requested comment on whether an exemption from the maintenance 
    requirement for the tape on the underride guard should be provided due 
    to practicability problems.4 NHTSA has forwarded King's 
    comment to FHWA for consideration. Irrespective of whether FHWA 
    continues to require motor carriers to maintain the conspicuity 
    treatment on the guards, NHTSA encourages manufacturers to design the 
    treatment to be as durable as practicable to ensure that the safety 
    benefits of applying the treatment to that location are realized.
    ---------------------------------------------------------------------------
    
        \4\ ``The [FHWA Notice of Proposed Rulemaking] does not, 
    however, include an exemption to the requirement that motor carriers 
    maintain the conspicuity material on the rear underride device. The 
    agency requests comments from motor carriers on the durability of 
    the conspicuity material located on the horizontal member of the 
    rear underride protection devices. Commenters are asked to identify 
    the specific types of trailers and operating conditions that they 
    believe are associated with the durability problems cited in 
    addition to providing color photographs of the damaged conspicuity 
    materials.'' 62 FR 18172-73.
    ---------------------------------------------------------------------------
    
        If FHWA requires the conspicuity treatment on the horizontal member 
    of the guard to be maintained, and sufficiently durable conspicuity 
    treatments are not available, NHTSA assumes that manufacturers would 
    design guards with channels or other protective features for the 
    conspicuity treatment. There is nothing in Standard No. 223 that would 
    prevent such designs. NHTSA will consult with FHWA on whether NHTSA 
    rulemaking to mandate physical protection for conspicuity treatment is 
    needed after FHWA completes its rulemaking.
    
    IV. Response to TTMA Petition on Extension of Effective Date
    
        In an April 18, 1997 letter, TTMA petitioned NHTSA to commence 
    rulemaking to extend the effective date from January 26, 1998 to a date 
    at least nine months after this response to the petitions for 
    reconsideration is issued. It stated only that trailer manufacturers 
    were reluctant to complete the designs of their guards and test these 
    guards until the petitions were answered.
        TTMA's petition for an extension of the effective date is denied. 
    NHTSA does not see any reason why manufacturers can not complete and 
    test their guard designs in the allotted time. Except for a few of Rite 
    Hite's requests, all the petitions dealt with relatively minor issues 
    of testing and clarification. Manufacturers should have been planning 
    to comply with the rule as it was published in January of 1996.
        The guards that will be required on January 26, 1998 are very 
    similar to guards currently being produced. NHTSA made no amendments 
    requiring configuration changes in its responses to the petitions. The 
    change to the regulatory text relating to vertical cross-sectional 
    height is basically a clarification of the current requirements. There 
    were only two minor changes to the test procedures (allowing a more 
    flexible force application rate and allowing the manufacturer to 
    designate the force application rate on which it based its 
    certification). These changes will make it easier for manufacturers to 
    test the guards and to comply with the requirements. The guards that 
    manufacturers will be required to produce after this rule is issued 
    will be essentially the same guards that NHTSA required in the January 
    1996 final rule. NHTSA notes that the TTMA's Recommended Practice, 
    ``Rear Impact Guard and Protection'' is virtually identical to the 
    NPRM, except for the energy absorption requirement of Standard No. 223. 
    This Recommended Practice is designated RP No. 92-94, and was 
    originally issued in April of 1994 and revised in November of 1994. 
    Apparently it has been adopted as an industry standard, so little 
    reengineering should be necessary to meet Standard No. 223. Therefore, 
    NHTSA believes that the manufacturers have had sufficient time to 
    complete their designs prior to the January 26, 1998 effective date. A 
    general extension is not warranted.
        However, the agency will consider petitions for temporary exemption 
    from Standard No. 224. The agency has received a number of these 
    petitions from small-volume trailer manufacturers within the past few 
    months. Under 49 CFR 555.6(a), a manufacturer whose yearly production 
    is not more than 10,000 units may ask for a temporary exemption from a 
    Federal motor vehicle safety standard for up to three years on the 
    basis that compliance would cause it substantial economic hardship and 
    that it has attempted in good faith to comply with the standard from 
    which it has asked to be excused. Part 555 requires the agency to 
    publish a notice in the Federal Register seeking public comment on each 
    exemption petition before a decision can be made on such a request, and 
    then publish a second notice either granting or denying the petition. 
    NHTSA expects to issue final decisions on these petitions approximately 
    three to four months after the date of submission of the petition.
    
    V. Technical Amendment on Logging Trailers
    
        The Application section (S3) of Standard No. 224 currently excludes 
    ``pole trailers'' from the application of the rule. Pole trailers are 
    trailers with a single, longitudinal telescoping pole, rather than a 
    normal trailer chassis, connecting the front wheels to the back wheels. 
    Pole trailers are predominantly used by the logging industry to 
    transport logs. They spend a great deal of their time off-road at 
    logging sites and on rough logging roads. NHTSA proposed to exclude 
    these vehicles in the January 8, 1981 NPRM (46 FR 2139), stating:
    
    the proposed rule does not apply to pole trailers. The agency 
    believes that requiring underride guards on such vehicles would 
    provide little benefit to car occupants. Since the poles carried by 
    these trailers normally overhang the back end of the vehicles for a 
    considerable distance, the danger of
    
    [[Page 3661]]
    
    underride is due not to the structure of the trailer but to the 
    structure of the cargo.
    
    This was not a controversial exclusion and it was retained in the 1992 
    Supplemental Notice of Proposed Rulemaking (SNPRM) and the 1996 final 
    rule without comment.
    
        Changes in the trailer design and in the logging industry since 
    1981 have led to a decline in the popularity of pole trailers and the 
    emergence of ``pulpwood trailers'' to take their place. Pulpwood 
    trailers are similar in use and structure to pole trailers, but they 
    have more structure (often two poles or beams) connecting the front 
    wheels to the back wheels. NHTSA has recently become aware, through an 
    April 25, 1997 letter from Mr. Buck Ford, that some manufacturers of 
    pulpwood trailers are deciding how to install underride guards to 
    comply with the January 1996 final rule, but that other manufacturers 
    are completely unaware of the rule. Pulpwood trailers are not currently 
    excluded because they are not technically pole trailers. According to 
    Mr. Ford, there may be a shortage of pulpwood trailers in 1998 due to 
    few manufacturers being able to meet the requirements.
        NHTSA intended to exclude all trailers that, like pole trailers, 
    lack structure for attaching guards and that would carry loads likely 
    to overhang the rear of the trailer substantially when it published the 
    January 1996 final rule. Pulpwood trailers do not differ significantly 
    from pole trailers in their construction or use. They also carry 
    overhanging logs that would negate the value of the underride guard and 
    operate on rough logging roads on which an underride guard would be a 
    serious impediment. Due to the lack of controversy regarding the 
    exclusion of pole trailers, and due to the lack of comment from 
    pulpwood trailer manufacturers, the agency assumed that the language of 
    the exclusion covered all trailers of this type.
        Because this appears to have been an incorrect assumption, NHTSA is 
    adding pulpwood trailers to the list of excluded vehicle types. This is 
    being done by technical amendment because the agency's intent to 
    exclude vehicles that carry this kind of load was clear from the 1981 
    NPRM's rationale for the exclusion. This technical amendment will also 
    avoid a shortage of pulpwood trailers needed by the logging industry in 
    1998. NHTSA is adopting the pertinent part of the language contained in 
    Standard No. 121, Air Brake Systems, which defines ``pulpwood trailer'' 
    as ``a trailer that is designed exclusively for harvesting logs or 
    pulpwood and constructed with a skeletal frame with no means for 
    attachment of a solid bed, body, or container * * *''.
    
    VI. Effective Date
    
        The agency finds that there is good cause to make this rule 
    effective immediately. These amendments do not impose any new 
    requirements. Instead, they relieve some of the testing burden imposed 
    on the manufacturers by the January 24, 1996 final rule. It will be 
    slightly easier for manufacturers to test using the new load 
    application rates specified in these amendments. These amendments also 
    make it clear that pulpwood trailers are an excluded category of 
    vehicle, and that cargo tank motor vehicles built to RSPA's standards 
    with a rear-end protection device or rear bumper in the area specified 
    for NHTSA's underride guard do not have to meet the energy absorption 
    requirements of Standard No. 223. A delayed effective date would impose 
    a needless compliance burden on the trailer industry, including many 
    small businesses that manufacture trailers.
    
    VII. Rulemaking Analyses and Notices
    
    A. Executive Order 12866 (Federal Regulation) and Regulatory Policies 
    and Procedures
    
        This rulemaking action was reviewed under Executive Order 12866. 
    The action has been determined to be ``not significant'' under 
    Executive Order 12866 and under the Department of Transportation 
    regulatory policies and procedures. The Final Regulatory Evaluation 
    (FRE) for the January 1996 final rule describes the economic and other 
    effects of that rule in detail.
        The responses to these petitions for reconsideration and this 
    technical amendment do not alter the costs or benefits of that rule 
    significantly. They merely clarify the intended application of the rule 
    and provide more flexibility in the test procedures. They do not change 
    the requirements enough to significantly alter the performance or the 
    price of rear underride guards. Therefore, a regulatory analysis is not 
    warranted.
    
    B. Regulatory Flexibility Act
    
        NHTSA analyzed the potential impacts of the January 1996 final rule 
    on small entities under the Regulatory Flexibility Act and certified 
    that it would have a significant economic impact on a substantial 
    number of small entities. NHTSA has described those possible impacts in 
    the FRE to the January 1996 final rule, which was, in part, a 
    regulatory flexibility analysis.
        The responses to these petitions for reconsideration and this 
    technical amendment slightly increase manufacturer flexibility in 
    testing, but NHTSA certifies that the changes made by today's rule do 
    not have a significant economic impact on a substantial number of small 
    entities. Most of the changes are interpretations and clarifications of 
    the existing language, not changes in requirements that impose new 
    burdens. The changes in requirements are designed to make the guards 
    easier for manufacturers, especially small businesses, to test their 
    guards, not to change the guard performance. As a result, some 
    businesses that otherwise would have had to buy sophisticated testing 
    equipment or change their guard designs unnecessarily will not need to 
    do so. Therefore, there will be no new significant impact on small 
    businesses.
    
    C. Executive Order 12612 (Federalism)
    
        NHTSA has analyzed this rule in accordance with the principles and 
    criteria contained in E.O. 12612, and has determined that this rule 
    will not have sufficient federalism implications to warrant the 
    preparation of a Federalism Assessment.
        This rule makes only minor changes to the January 1996 final rule 
    which had only minimal federalism implications. Nearly all States 
    require underride protection guards for heavy trailers and 
    semitrailers. Further, most states require that the guards meet certain 
    configuration requirements, or that they be positioned in a certain 
    location relative to the rear and sides of the vehicle. The January 
    1996 final rule will preempt State requirements for rear impact 
    protection. However, the agency believes that federalism implications 
    will be minor because the guards required by that final rule are not 
    fundamentally different from those required by State law. Several 
    States, including Michigan, North Carolina, New York, and New Jersey, 
    already require trailers longer than 15 m (50 ft) to have guards with 
    the configuration required by that rule. For practical purposes, the 
    only effect that that rule will have in these States is to require the 
    guards to be tested and certified for strength and energy absorption.
        NHTSA believes that effective rear impact protection measures can 
    be implemented only at the national level. Only vehicle manufacturers 
    can produce trailers and semitrailers with improved rear impact 
    protection. The improvements required by the January 1996 final rule 
    will cause vehicle manufacturers and operators to incur costs that 
    could affect their competitive
    
    [[Page 3662]]
    
    position if compliance were voluntary and attempted by some, but not 
    all manufacturers. That rule applies uniformly to all manufacturers and 
    will ensure that the competitive position of the manufacturers will not 
    be significantly affected by the required safety improvements.
    
    D. Preemptive Effect and Judicial Review
    
        Under 49 U.S.C. Sec. 30103(b), whenever a Federal motor vehicle 
    safety standard is in effect, a State may not adopt or maintain a 
    safety standard applicable to the same aspect of performance which is 
    not identical to the Federal standard. 49 U.S.C. Sec. 30161 sets forth 
    a procedure for judicial review of final rulemaking establishing, 
    amending, or revoking Federal motor vehicle safety standards. That 
    section does not require submission of a petition for reconsideration 
    or other administrative proceeding before parties may file suit in 
    court. This final rule does not have any retroactive effect.
    
    E. Paperwork Reduction Act
    
        In accordance with the Paperwork Reduction Act of 1980 (P.L. 96-
    511), there are no new requirements for information collection 
    associated with this response to petitions for reconsideration and 
    technical amendment.
    
    List of Subjects in 49 CFR Part 571
    
        Imports, Incorporation by reference, Motor vehicle safety, Motor 
    vehicles, Rubber and rubber products, Tires.
    
    PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS
    
        In consideration of the foregoing, 49 CFR part 571 is amended as 
    follows:
        1. The authority citation for part 571 continues to read as 
    follows:
    
        Authority: 49 U.S.C. 322, 30111, 30115, 30117 and 30166; 
    delegation of authority at 49 CFR 1.50
    
        2. Sections S5.1 and S6.6(a) of 49 CFR 571.223 are revised to read 
    as follows:
    
    
    Sec. 571.223  Standard No. 223; rear impact guards
    
    * * * * *
        S5.1  Projected Vertical Height. The horizontal member of each 
    guard, when viewed from the rear as it would be installed on a trailer 
    pursuant to the installation instructions or procedures required by 
    S5.5 of this standard, shall have a vertical height of at least 100 mm 
    at each point across the guard width, when projected horizontally on a 
    transverse vertical plane. Those installation instructions or 
    procedures shall specify that the guard is to be mounted so that all 
    portions of the horizontal member necessary to achieve a 100 mm high 
    projected vertical height are located not more than 305 mm forward of 
    the vehicle's rear extremity, as defined in S4 of 49 CFR 571.224, Rear 
    Impact Protection. See Figure 1 of this section.
    * * * * *
        S6.6  Force Application.
    * * * * *
        (a) Using the force application device, apply force to the guard in 
    a forward direction such that the displacement rate of the force 
    application device is the rate, plus or minus 10 percent, designated by 
    the guard manufacturer within the range of 2.0 cm per minute to 9.0 cm 
    per minute. If the guard manufacturer does not designate a rate, any 
    rate within that range may be chosen.
    * * * * *
        3. In Sec. 571.224 section S3 is revised and section S4 is amended 
    by adding a definition of pulpwood trailer and revising the definition 
    of Special purpose vehicle to read as follows:
    
    
    Sec. 571.224  Standard No. 224; rear impact protection
    
    * * * * *
        S3. Application. This standard applies to trailers and semitrailers 
    with a GVWR of 4,536 kg or more. The standard does not apply to pole 
    trailers, pulpwood trailers, special purpose vehicles, wheels back 
    vehicles, or temporary living quarters as defined in 49 CFR 529.2.
        If a cargo tank motor vehicle, as defined in 49 CFR 171.8, is 
    certified to carry hazardous materials and has a rear bumper or rear 
    end protection device conforming with 49 CFR part 178 located in the 
    area of the horizontal member of the rear underride guard required by 
    this standard, the guard need not comply with the energy absorption 
    requirement (S5.2.2) of 49 CFR 571.223.
        S4. Definitions.
    * * * * *
        Pulpwood trailer means a trailer that is designed exclusively for 
    harvesting logs or pulpwood and constructed with a skeletal frame with 
    no means for attachment of a solid bed, body, or container.
    * * * * *
        Special purpose vehicle means a trailer or semitrailer having work-
    performing equipment that, while the vehicle is in transit, resides in 
    or moves through the area that could be occupied by the horizontal 
    member of the rear underride guard, as defined by S5.1.1 through 
    S5.1.3.
    * * * * *
        Issued on: January 20, 1998.
    Ricardo Martinez,
    Administrator.
    [FR Doc. 98-1783 Filed 1-21-98; 2:18 pm]
    BILLING CODE 4910-59-P
    
    
    

Document Information

Effective Date:
1/26/1998
Published:
01/26/1998
Department:
National Highway Traffic Safety Administration
Entry Type:
Rule
Action:
Final rule; response to petitions for reconsideration; technical amendment; denial of petition to extend the effective date.
Document Number:
98-1783
Dates:
The amendments made by this rule will become effective on January 26, 1998. Petitions for reconsideration of this rule must be received no later than March 12, 1998.
Pages:
3654-3662 (9 pages)
Docket Numbers:
Docket NHTSA-98-3342, Notice 1
RINs:
2127-AA43: Truck Rear Underride Protection
RIN Links:
https://www.federalregister.gov/regulations/2127-AA43/truck-rear-underride-protection
PDF File:
98-1783.pdf
CFR: (3)
49 CFR At
49 CFR 571.223
49 CFR 571.224