Parts and Accessories Necessary for Safe Operation; General Amendments, 48008-48055 [05-14259]

Agencies

• Federal Motor Carrier Safety Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 70, Number 156 (Monday, August 15, 2005)]
[Rules and Regulations]
[Pages 48008-48055]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-14259]



[[Page 48007]]

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Part III





Department of Transportation





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Federal Motor Carrier Safety Administration



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49 CFR Parts 390, 392, and 393



Parts and Accessories Necessary for Safe Operation; General Amendments; 
Final Rule

Federal Register / Vol. 70, No. 156 / Monday, August 15, 2005 / Rules 
and Regulations

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DEPARTMENT OF TRANSPORTATION

Federal Motor Carrier Safety Administration

49 CFR Parts 390, 392 and 393

[Docket No. FMCSA-1997-2364]
RIN 2126-AA61


Parts and Accessories Necessary for Safe Operation; General 
Amendments

AGENCY: Federal Motor Carrier Safety Administration (FMCSA), DOT.

ACTION: Final rule.

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SUMMARY: FMCSA amends part 393 of the Federal Motor Carrier Safety 
Regulations (FMCSRs), Parts and Accessories Necessary for Safe 
Operation. The amendments are intended to remove obsolete and redundant 
regulations; respond to several petitions for rulemaking; provide 
improved definitions of vehicle types, systems, and components; resolve 
inconsistencies between part 393 and the National Highway Traffic 
Safety Administration's Federal Motor Vehicle Safety Standards (49 CFR 
part 571); and codify certain FMCSA regulatory guidance concerning the 
requirements of part 393. Generally, the amendments do not involve the 
establishment of new or more stringent requirements, but a 
clarification of existing requirements. This action is intended to make 
many sections more concise, easier to understand and more performance 
oriented.

DATES: The rule is effective September 14, 2005. The publications 
incorporated by reference in this final rule are approved by the 
Director of the Office of the Federal Register as of September 14, 
2005.

FOR FURTHER INFORMATION CONTACT: Mr. Jeffrey J. Van Ness, Vehicle and 
Roadside Operations Division, Federal Motor Carrier Safety 
Administration, 202-366-0676, 400 Seventh Street, SW., Washington, DC 
20590.

SUPPLEMENTARY INFORMATION:

Legal Basis for the Relemaking

    This rulemaking is based on the authority of the Motor Carrier Act 
of 1935 and the Motor Carrier Safety Act of 1984 (49 U.S.C. 31131 et 
seq.).
    The Motor Carrier Act of 1935, as amended, provides that ``[t]he 
Secretary of Transportation (Secretary) may prescribe requirements for: 
(1) Qualifications and maximum hours-of-service of employees of, and 
safety of operation and equipment of, a motor carrier; and (2) 
qualifications and maximum hours-of-service of employees of, and 
standards of equipment of, a private motor carrier, when needed to 
promote safety of operation.'' (49 U.S.C. 31502(b)).
    This final rule amends the Federal Motor Carrier Safety Regulations 
(FMCSRs) to remove obsolete and redundant regulations; respond to 
several petitions for rulemaking; provide improved definitions of 
vehicle types, systems, and components; resolve inconsistencies between 
part 393 and the National Highway Traffic Safety Administration's 
Federal Motor Vehicle Safety Standards (49 CFR part 571); and codify 
certain FMCSA regulatory guidance concerning the requirements of part 
393. Generally, the amendments do not involve the establishment of new 
or more stringent requirements, but a clarification of existing 
requirements. This action is intended to make many sections more 
concise, easier to understand and more performance oriented. The 
adoption and enforcement of such rules is specifically authorized by 
the Motor Carrier Act of 1935. This final rule rests squarely on that 
authority.
    The Motor Carrier Safety Act of 1984 provides concurrent authority 
to regulate drivers, motor carriers, and vehicle equipment. It requires 
the Secretary to ``prescribe regulations on commercial motor vehicle 
safety.'' The regulations shall prescribe minimum safety standards for 
commercial motor vehicles. At a minimum, the regulations shall ensure 
that: (1) Commercial motor vehicles are maintained, equipped, loaded, 
and operated safely; (2) the responsibilities imposed on operators of 
commercial motor vehicles do not impair their ability to operate the 
vehicles safely; (3) the physical condition of operators of commercial 
motor vehicles is adequate to enable them to operate vehicles safely; 
and (4) the operation of commercial motor vehicles does not have a 
deleterious effect on the physical condition of the operators' (49 
U.S.C. 31136(a)).
    This final rule concerns parts and accessories necessary for the 
safe operation of commercial motor vehicles. It is based primarily on 
section 31136(a)(1) and (2), and secondarily on section 31136(a)(4). 
This rulemaking would ensure CMVs are maintained, equipped, loaded, and 
operated safely by requiring certain vehicle components, systems and 
equipment to meet minimum standards such that the mechanical condition 
of the vehicle is not likely to cause a crash or breakdown.
    The final rule provides improved guidance concerning parts and 
accessories to CMV drivers who are responsible for ensuring vehicles 
are in safe and proper operating condition before each trip, and 
reporting to their employers any defects or deficiencies observed by, 
or reported to, the driver during the work day. By ensuring commercial 
motor vehicles are in safe and proper working order, it is less likely 
that the mechanical condition of the vehicle would cause a crash or 
breakdown. Therefore, drivers' responsibilities for the operation of 
their commercial motor vehicles do not, if fulfilled in accordance with 
the regulations, impair their ability to operate vehicles safely.
    Finally, the rulemaking would ensure the operation of CMVs does not 
have a deleterious effect on the physical condition of the operators of 
vehicles by requiring vehicle components and systems meet specific 
performance requirements. Compliance with these requirements would help 
to ensure that the mechanical condition of the vehicle is not likely to 
cause a crash or breakdown.
    Therefore, FMCSA considers the requirements of 49 U.S.C. 31136 
(a)(1), (2) and (4) to be applicable to this rulemaking action. The 
rulemaking would amend regulations concerning commercial vehicle 
equipment, prescribe regulations applicable to the responsibilities 
frequently imposed upon drivers to ensure their ability to operate 
safely is not impaired, and help to prevent serious injuries to CMV 
drivers that could result from improperly secured loads.
    With regard to 49 U.S.C. 31136(a)(3), FMCSA does not believe this 
provision concerning the physical condition of drivers is applicable to 
this rulemaking because this rulemaking does not concern the 
establishment of driver qualifications standards. This final rule 
addresses safety requirements applicable to commercial motor vehicle 
parts and accessories necessary for safe operation and does not include 
issues related to the physical qualifications or physical capabilities 
of drivers who must operate such vehicles.
    However, before prescribing any such regulations, FMCSA must 
consider the ``costs and benefits'' of any proposal (49 U.S.C. 
31136(c)(2)(A)).
    This final rule requires commercial motor vehicles to be 
maintained, equipped and operated safely. It removes obsolete and 
redundant regulations; responds to several petitions for rulemaking; 
provides improved definitions of vehicle types, systems, and 
components; resolves inconsistencies between part 393 and the National 
Highway Traffic Safety Administration's Federal Motor Vehicle

[[Page 48009]]

Safety Standards (49 CFR part 571); and codifies certain FMCSA 
regulatory guidance concerning the requirements of part 393. The 
fundamental purpose of 49 CFR part 393 Parts and Accessories Necessary 
for Safe Operation is to ensure that no employer shall operate a 
commercial motor vehicle or cause or permit it to be operated, unless 
it is equipped in accordance with the requirements and specifications 
of this part. However, nothing contained in part 393 shall be construed 
to prohibit the use of additional equipment and accessories, not 
inconsistent with or prohibited by part 393, provided such equipment 
and accessories do not decrease the safety of operation of the motor 
vehicles on which they are used. Compliance with the rules concerning 
parts and accessories is necessary to ensure vehicles are equipped with 
the specified safety devices and equipment.

Background

    On April 7, 1997, the Federal Highway Administration (FHWA) 
published a notice of proposed rulemaking (NPRM) to amend part 393 (62 
FR 18170). FHWA received numerous petitions for rulemaking and requests 
for interpretation of the requirements of part 393 which raised the 
need for amendments to clarify several provisions of the safety 
regulations. In addition, the National Highway Traffic Safety 
Administration (NHTSA), the Federal agency responsible for establishing 
safety standards for the manufacture of motor vehicles and certain 
motor vehicle equipment, made several amendments to its Federal Motor 
Vehicle Safety Standards (FMVSSs) that necessitate amendments to the 
FMCSRs in order to eliminate inconsistencies between part 393 and the 
FMVSSs. Comments were requested by June 13, 1997.

Extension of Comment Period

    On June 12, 1997, FHWA published a notice in the Federal Register 
to extend the comment period until July 28, 1997 (69 FR 32066). The 
extension was in response to a request from the Motor Equipment 
Manufacturers Association (MEMA) (62 FR 32066). MEMA requested the 
extension in order to develop what it described as ``meaningful and 
responsive comments'' to the proposed revisions of Sec.  393.25, 
Requirements for lamps other than head lamps, Sec.  393.45, Brake 
tubing and hose adequacy, and Sec.  393.46, Brake tubing and hose 
connections. A copy of the MEMA request is included in the docket.

Publication of Final Rule on Sec.  393.60, Glazing in Specified 
Openings

    On January 9, 1998, FHWA revised its requirements concerning 
glazing materials, windshield condition, coloring and tinting of 
windshields and windows, and obstruction to the driver's field of view 
for commercial motor vehicles operated in interstate commerce (63 FR 
1383). The revision was intended to remove obsolete regulatory 
language, establish requirements that were more performance-based than 
the previous rules, and respond to requests for waivers to allow the 
use of windshield-mounted transponders. The agency had proposed 
revising Sec.  393.60 as part of the April 14, 1997, NPRM. Upon review 
of the docket comments and requests for waivers, the agency decided to 
issue a final rule on glazing materials, windshields and windows and to 
publish, at a later date, a final rule on the remaining issues covered 
in the NPRM.

Public Meeting About the Proposed Changes to the Brake Hose Regulations

    On March 24, 1998, FHWA held a public meeting to discuss 
requirements for brake hoses used on commercial motor vehicles. An 
announcement of the meeting was published in the Federal Register on 
February 20, 1998 (63 FR 8606). Several brake hose manufacturers 
submitted comments in response to the 1997 notice of proposed 
rulemaking expressing opposition to the proposed changes to Sec. Sec.  
393.45 and 393.46. They believe the proposed removal of references to 
the Society of Automotive Engineers' (SAE) standards would have an 
adverse impact on safety. Some of the brake hose manufacturers 
contacted members of Congress to voice their concerns. As a result, the 
agency received numerous calls from congressional staff and letters 
from members of the House and Senate.
    At the request of congressional staff, FHWA met with 
representatives from several congressional offices on October 24, 1997, 
to explain the proposed rulemaking and the roles of the FHWA and the 
NHTSA. During this meeting FHWA offered to hold a public meeting 
concerning brake hoses. The meeting was intended to initiate dialogue 
between FHWA, NHTSA, manufacturers of brake hoses, brake hose 
assemblies, and brake hose end fittings for use on commercial motor 
vehicles, and interested parties concerning the adequacy of Federal 
requirements for brake hoses and related components. Copies of 
presentations made by the participants are included in the docket.
    On October 30, 1998, three brake manufacturers, Elf Atochem North 
America, Inc., Mark IV Industrial/Dayco Eastman, and Parker Hannifin 
Corporation \1\ filed a joint petition for rulemaking with NHTSA. The 
petitioners requested that certain requirements relating to brake 
hoses, brake hose tubing, and brake hose end fittings that are 
administered by FHWA be incorporated into FMVSS No. 106 (49 CFR 
571.106). Specifically, the petitioners requested incorporation of the 
requirements of 49 CFR 393.45 (Brake tubing and hose, adequacy) and 49 
CFR 393.46 (Brake tubing and hose connections) into FMVSS No. 106. On 
May 15, 2003, NHTSA published an NPRM proposing amendments to FMVSS No. 
106 (68 FR 26384). On December 20, 2004 NHTSA published its final rule 
amending FMVSS No. 106 (69 FR 76298).
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    \1\ Since the petition was filed with NHTSA, Mark IV Industrial/
Dayco Eastman has been acquired by Parker Hannifin Corporation. Elf 
Atochem North America, Inc. was integrated into Atofina Chemical, 
Inc. The successor petitioning companies are referred to as Parker/
Atofina.
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    In consideration of NHTSA's revision of FMVSS No. 106, FMCSA 
believes the issues raised by commenters responding to the proposed 
revisions to 49 CFR 393.45 and 393.46 have been resolved through 
NHTSA's rulemaking.

Discussion of Comments Received in Response to the April 14, 1997, NPRM

    The agency received 36 comments in response to the NPRM. The 
commenters were: Air Ride Control, Inc.; Amerex Corporation; the 
American Trucking Associations (ATA) (two submissions to the docket); 
Burns Consulting Associates; Colorado Department of Public Safety; 
Commercial Vehicle Safety Alliance (CVSA) (two submissions to the 
docket); Robert J. Crail, a transportation engineering consultant; W. 
E. Currie, a consulting engineer; Dana Corporation, Boston Weatherhead 
Division; Electronic Controls Company; Elf Atochem North America, Inc.; 
Georgia Public Service Commission; Grote Industries, Inc.; H[uuml]ls 
America, Inc.; Lufkin Trailers; Mark IV Industrial--Dayco Eastman; The 
Commonwealth of Massachusetts, Department of Public Utilities; National 
Association of State Fire Marshals; National Association of Trailer 
Manufacturers; National Automobile Dealers Association; National 
Automobile Transporters Association; National Propane Gas Association; 
Oklahoma Highway Patrol; Parker Hannifin Corporation (two submissions 
to the docket); Rockwell International Corporation (the automotive 
division of

[[Page 48010]]

Rockwell is now Meritor Automotive); Star Headlight and Lantern 
Company, Inc.; Transportation Safety Equipment Institute; Truck 
Manufacturers Association; Truck Trailer Manufacturers Association; UBE 
Industries (America), Inc.; Donald H. Verhoff; and, Wells Cargo, Inc.
    Of the comments received, 10 focused on the issue of the agency's 
proposal to remove references to certain SAE brake hose standards and 
recommended practices. Because this issue is being addressed through a 
separate rulemaking by NHTSA, FMCSA will not provide a discussion of 
brake hose manufacturing standards.
    With regard to the remaining comments, the majority of the 
commenters supported the proposed amendments. Several, however, 
suggested minor enhancements or modifications to the specific wording 
proposed by the agency, or changes in terminology. For example, a 
transportation engineering consultant suggested we use ``upper beam'' 
and ``lower beam'' when describing headlight terminology. Along similar 
lines, AMERIX Corporation, a fire extinguisher manufacturer, advised us 
that the type 4B:C extinguisher referenced in the proposed amendments 
to Sec.  393.95 is no longer manufactured.
    The National Association of State Fire Marshals (NASFM) argued that 
this rulemaking does nothing to address their 1995 petition to amend 
the FMCSRs to require fire extinguishers on all lightweight vehicles 
(under 10,000 pounds gross vehicle weight rating (GVWR)), operated in 
interstate commerce. A copy of the petition was attached. The Agency 
previously explained to NASFM that generally, the FMCSRs are not 
applicable to lightweight vehicles and that the reference to 
lightweight vehicles under 49 CFR 393.95 was an error. The term was 
supposed to have been removed when the agency incorporated the 
statutory definition of CMV from the Motor Carrier Act of 1984. Fire 
extinguishers are required on all power units subject to the FMCSRs, 
including vehicles designed or used to transport 9 to 15 passengers 
(including the driver), for direct compensation, if the vehicle is 
driven more than 75 air miles beyond the driver's normal work reporting 
location. This rulemaking was never intended to address this issue.

Amendments to 49 CFR Parts 390, 392 and 393: Section-by-Section 
Discussion of the Amendments

Part 390, Subpart A--General Applicability and Definitions

Section 390.5--Definition of Driveaway-Towaway Operation
    Parts 393 and 396 of the FMCSRs include several exceptions for 
driveaway-towaway operations. Currently, a driveaway-towaway operation 
is defined as one in which a motor vehicle constitutes the commodity 
being transported and one or more set of wheels of the vehicle being 
transported are on the surface of the roadway during transportation. 
The driveaway-towaway exceptions are intended to address situations in 
which compliance with some of the vehicle regulations is not 
practicable because of the circumstances surrounding the delivery or 
transportation of the vehicle. Examples of driveaway-towaway operations 
include the delivery of a newly manufactured commercial motor vehicle 
from a manufacturer to a dealership, the delivery of a new or used 
motor vehicle from the dealership to the purchaser, or certain 
movements of vehicles to a repair or maintenance facility. Among the 
provisions of parts 393 and 396 which do not apply to driveaway-towaway 
operations are the requirements for lamps and reflectors, brakes, 
driver vehicle inspection reports, maintenance records, and periodic 
inspection.
    The concept of providing exceptions for such operations dates back 
to the former Interstate Commerce Commission's (ICC) May 27, 1939, 
Order under Ex-Parte No. MC-2 (14 M.C.C. 669, at 679). A driveaway-
towaway operation was originally defined by the ICC as ``any operation 
in which a single motor vehicle or combination of motor vehicles, new 
or used, constitutes the commodity being transported and in which the 
motive power of any such motor vehicles is utilized.'' In 1952, the ICC 
revised the definition to read ``any operation in which any motor 
vehicle or motor vehicles, new or used, constitute the commodity being 
transported, when one or more set of wheels of any such motor vehicle 
or motor vehicles are on the roadway during the course of 
transportation; whether or not any such motor vehicle furnishes the 
motive power.'' (17 FR 4422, 4423, May 15, 1952).
    The current definition of a driveaway-towaway operation was 
published on May 19, 1988 (53 FR 18052). FMCSA continues to believe the 
definition does not provide sufficient guidance in identifying the 
specific types of vehicle operations covered. Therefore, FMCSA revises 
the definition of driveaway-towaway operation to limit the use of the 
various exceptions to situations in which motor vehicles are being 
transported: (1) Between vehicle manufacturer's facilities, (2) between 
a vehicle manufacturer and a dealership or a purchaser, (3) between a 
dealership, or other entity selling or leasing the vehicle, and a 
purchaser or lessee, (4) to a motor carrier's terminal or repair 
facility for the repair of disabling damage (as defined in Sec.  390.5) 
following a crash, (5) to a motor carrier's terminal or repair facility 
for repairs associated with the failure of a vehicle component or 
system, or (6) by means of a saddle-mount or tow-bar. In addition, the 
driveaway-towaway exceptions are applicable only in those cases where 
the motor vehicles are not transporting cargo or passengers. The 
revision is intended to reduce confusion and it is responsive to 
commenters who requested that the definition include movements of 
vehicles between manufacturers' facilities, and the towing of vehicles 
after a breakdown.

Part 392, Subpart D--Use of Lighted Lamps and Reflectors

Section 392.33--Obscured Lamps or Reflector
    FMCSA amends Sec.  392.33 to include an exception for the 
obstruction of trailer conspicuity treatments on the front end 
protection device. The NHTSA requires trailer manufacturers to apply 
retroreflective sheeting to the front end protection devices or 
headerboards of trailers manufactured on or after December 1, 1993 (49 
CFR 571.108, S5.7.1.4, entitled location). Because the headerboard is 
located at the front of flatbed trailers, the cargo may, depending upon 
its height, obstruct the conspicuity material located on the 
headerboard. FMCSA recognizes that this temporary obstruction of the 
reflective material cannot be avoided in many cases and does not 
believe that it is appropriate to penalize motor carriers if this 
occurs.

Part 393, Subpart A--General

Section 393.1--Scope of the Rules of This Part
    FMCSA is revising Sec.  393.1 to clarify the applicability of the 
requirements of part 393. Although Sec.  390.3 explains the 
applicability of the FMCSRs, and Sec.  390.5 defines the term 
``commercial motor vehicle,'' many private motor carriers of property 
and private motor carriers of passengers do not understand

[[Page 48011]]

the applicability of the provisions in part 393 when a lightweight 
vehicle is used to tow a trailer in interstate commerce. With the 
exception of vehicles designed or used to transport 9 to 15 passengers 
(including the driver), for direct compensation, more than 75 air miles 
beyond the driver's normal work reporting location, and vehicles 
transporting certain quantities of hazardous materials, vehicles with a 
GVWR below 4,536 kg (10,001 pounds) or designed to transport less than 
16 passengers are not subject to the FMCSRs when operated singly in 
interstate commerce. However, when a small vehicle is coupled to a 
trailer, the gross combination weight rating (GCWR) often exceeds 4,536 
kg (10,001 pounds), making the combination subject to the FMCSRs.
    Part 393 cross-references several Federal Motor Vehicle Safety 
Standards which distinguish between vehicles above and below 4,536 kg 
(10,001 pounds) and passenger vehicles designed to transport fewer than 
16 passengers. This rulemaking includes numerous proposals to clarify 
the cross-references to the FMVSS so that carriers and inspectors can 
readily locate the applicable paragraphs within the FMVSSs. The 
amendment to Sec.  393.1 is consistent with that goal.
Section 393.5--Definitions
    FMCSA is amending Sec.  393.5 by adding definitions of air brake 
system, air-over-hydraulic brake subsystem, auxiliary driving lamp, 
boat trailer, brake power assist unit, brake power unit, electric brake 
system, emergency brake, front fog lamp, hydraulic brake system, 
intermodal shipping (cargo) containers, multi-piece windshield, split 
service brake system, tow bar, trailer kingpin, vacuum brake system, 
and windshield. In addition, the definitions for chassis, clearance 
lamp, container chassis, heater, heavy hauler trailer, parking brake 
system, side marker lamps (intermediate), and side marker lamps are 
revised. The definition of bus is being removed from Sec.  393.5 in 
favor of the definition found in Sec.  390.5.
    The definitions of brake systems and components make the brake 
requirements under subpart C of part 393 easier to understand and 
enforce.
    The definitions of an air brake system and an air-over-hydraulic 
brake subsystem are based upon NHTSA's July 18, 1995, final rule on 
FMVSS No. 121 (60 FR 36741). The NHTSA amended FMVSS No. 121 to include 
a definition of an air-over-hydraulic brake subsystem and to make it 
clear that vehicles equipped with such systems are classified as air 
braked vehicles. In initially issuing FMVSS No. 121, NHTSA stated that 
``it should be noted that the term `air brake system' as defined in the 
standard applies to the brake configuration commonly referred to as 
`air-over-hydraulic,' in which failure of either medium can result in 
complete loss of braking ability.'' (36 FR 3817, February 27, 1971). 
Because NHTSA has considered air-over-hydraulic brake systems subject 
to FMVSS No. 121 for more than 20 years, FMCSA's adoption of NHTSA's 
definitions are not likely to affect the applicability of the brake 
requirements under part 393.
    The amended definition of a boat trailer is the same as that 
contained in 49 CFR Sec.  571.3. The NHTSA defines boat trailer as ``a 
trailer designed with cradle-type mountings to transport a boat and 
configured to permit launching of the boat from the rear of the 
trailer.'' FMCSA includes this definition because Sec.  393.11 includes 
requirements for lamps and reflectors on boat trailers.
    FMCSA is replacing its definition of ``emergency brake system'' 
with NHTSA's definition for ``emergency brake.'' This change ensures 
consistency between FMCSA's brake regulations covering motor carriers 
and NHTSA's regulations covering manufacturers.
    The agency is adopting NHTSA's FMVSS No. 105 definition of a split 
service brake system and includes it under Sec.  393.5 to improve the 
clarity of the hydraulic brake system requirements under subpart C of 
part 393.
    Definitions of an electric brake system and a vacuum brake system 
are added to Sec.  393.5 to support other revisions to the brake system 
requirements of part 393. Because there are no FMVSSs which cover 
electric and vacuum brake systems, many of the brake requirements under 
part 393 are de facto manufacturing standards. To better identify the 
applicable requirements, however, the revisions to subpart C 
specifically reference electric and vacuum brakes. These definitions 
prevent confusion or misunderstandings on the part of motor carriers 
and enforcement officials.
    With regard to the definition of a chassis, the agency is deleting 
the current reference to a ``truck or trailer'' in favor of the term 
``commercial motor vehicle,'' which includes trucks, truck tractors, 
trailers, buses and converter dollies. This is especially necessary 
since the definition of a truck in Sec.  390.5 explicitly excludes 
truck tractors.
    The definition of a clearance lamp is being replaced with one that 
appeared in the Society of Automotive Engineers' definition (Glossary 
of Automotive Terms, SP-750, February 1988). Although the SAE 
publication is now out-of-print, the Agency continues to believe the 
SAE definition provides a better description of the location and 
function of the clearance lamps than the current definition in Sec.  
393.5.
    As for the definition of a heater, FMCSA is amending the reference 
to paragraph (1) [the number ``one''] of Sec.  177.834 with a reference 
to paragraph (l) [the letter ``l']. The reference to paragraph (1) [the 
number ``1''] was a typographical error.
    A definition of a trailer kingpin is being added to cover non-
driveaway-towaway operations. Currently, the definition of a saddle-
mount includes a description of a ``king-pin.'' However, this 
definition does not appear to be appropriate for the trailer kingpin 
nor is the definition the same as that in the SAE's Truck & Bus 
Industry Glossary, SP-732, February 1988. Although the SAE publication 
is now out-of-print, FMCSA continues to believe the SAE's definition 
will ensure that definitions in part 393 are consistent with industry 
definitions.
    To clarify the applicability of parking brake requirements, the 
agency is amending the definition of a parking brake system in Sec.  
393.5 to replace the term ``vehicle'' with ``motor vehicle,'' which is 
defined in Sec.  390.5.
    The agency is amending the definitions of ``side marker lamp 
(intermediate)'' and ``side marker lamp'' to include motor vehicles 
other than trailers. Currently, both terms are defined only in the 
context of trailers. However, side marker lamps are required on almost 
all motor vehicles and intermediate side marker lamps are required on 
almost all motor vehicles more than 914.4 centimeters (cm) (30 feet) in 
length. Therefore, FMCSA is revising the definitions to include trucks, 
truck-tractors, and buses and to make both definitions consistent with 
the requirements under Sec.  393.11 relating to side marker lamps and 
FMVSS No. 108, NHTSA's requirements for lamps and reflective devices.
    On November 23, 1990, NHTSA amended its definition of a heavy 
hauler trailer to specifically exclude container chassis trailers (55 
FR 48850). To maintain consistency between the definitions used by the 
FMCSA and NHTSA, FMCSA is amending its definition of a heavy hauler 
trailer to exclude container chassis trailers as well.

[[Page 48012]]

Subpart B--Lighting Devices, Reflectors, and Electrical Equipment

    FMCSA revises the title of subpart B to read ``Lamps, Reflective 
Devices, and Electrical Wiring.'' The new title is more consistent with 
the title of FMVSS No. 108, entitled ``Lamps, reflective devices, and 
associated equipment.'' The new title would reference electrical wiring 
instead of associated equipment because subpart B includes electrical 
wiring requirements for several vehicle systems in addition to the 
lamps required by FMVSS No. 108.
Section 393.9--Lamps Operable
    FMCSA amends Sec.  393.9 to codify regulatory guidance concerning 
the use of lamps which are not required by Sec.  393.11 and FMVSS No. 
108, and to address obstruction of lamps. Section 393.9 requires that 
lamps be capable of being operated at all times. FMCSA has issued 
regulatory guidance indicating that Sec.  393.9 is only applicable to 
those lamps which are required by the FMCSRs. Therefore, if a motor 
carrier installs additional lamps which are found to be inoperable, for 
whatever reason, the carrier should not be considered in violation of 
Sec.  393.9. FMCSA amends Sec.  393.9 to codify this regulatory 
guidance.
Section 393.11--Lighting Devices and Reflectors
    FMCSA revises the title of Sec.  393.11 to read ``Lamps and 
reflective devices'' to maintain consistency between the title for 
subpart B and Sec.  393.11. The FMCSA is also amending Sec.  393.11 to 
require that commercial motor vehicles manufactured on or after 
December 25, 1968, meet the requirements of FMVSS No. 108 in effect at 
the time of manufacture, or any subsequent requirements under FMVSS No. 
108. Currently, Sec.  393.11 only requires that vehicles manufactured 
on or after March 7, 1989, meet the requirements of FMVSS No. 108. 
Vehicles manufactured prior to March 7 may meet either FMVSS No. 108 or 
the requirements of part 393 in effect on the date of manufacture.
    Because NHTSA's FMVSS No. 108 became effective on December 25, 
1968, manufacturers have been required to meet these requirements since 
that date. FMCSA's reference to March 7, 1989, under Sec.  393.11 is 
therefore inappropriate. Vehicles manufactured between December 25, 
1968, and March 7, 1989, were originally manufactured to meet FMVSS No. 
108, and motor carriers who have maintained lamps and reflectors in the 
required locations for these older vehicles would not be affected by 
the revision.
    In addition, FMCSA revises Sec.  393.11 to provide better guidance 
on the requirements for trailers, and to correct several omissions in 
Table 1 of that section. The paragraph preceding Table 1 does not 
present a clear statement of the requirements for lamps and reflectors.
    On December 10, 1992, NHTSA published a final rule requiring that 
trailers manufactured on or after December 1, 1993, which have an 
overall width of 2,032 mm (80 inches) or more and a GVWR of more than 
4,536 kg (10,000 pounds), be equipped on the sides and rear with a 
means for making them more visible on the road (57 FR 238). Trailers 
manufactured exclusively for use as offices or dwellings are exempt.
    NHTSA's rule allows trailer manufacturers to install either red and 
white retroreflective sheeting or reflex reflectors. Manufacturers of 
retroreflective sheeting or reflectors are required to certify 
compliance of their product with FMVSS No. 108 (49 CFR 571.108) whether 
the product is for use as original or replacement equipment.
    Currently, Sec.  393.11 requires that all lamps and reflective 
devices on motor vehicles placed in operation after March 7, 1989, meet 
the requirements of FMVSS No. 108 in effect on the date of manufacture. 
Therefore, trailers manufactured on or after December 1, 1993, must 
have reflective devices of the type and in the locations specified by 
FMVSS No. 108. To make certain that all motor carriers operating 
trailers subject to the FMCSRs are aware of their responsibility to 
maintain the conspicuity treatment, FMCSA is adding detailed language 
under Sec.  393.11. FMCSA cross-references the specific paragraphs of 
FMVSS No. 108 related to the applicability of NHTSA's trailer 
conspicuity standards, the required locations for the conspicuity 
material, and the certification and marking requirements.
    FMCSA notes that during NHTSA's rulemaking, the issue of requiring 
conspicuity material on the rear underride device generated industry 
concerns about the maintainability of the retroreflective sheeting in 
that location. As stated in the preamble to NHTSA's December 10, 1992, 
final rule:

    Objections were based on the potential for frequent damage that 
would cause trailers in use to fail inspections by [FMCSA]. NHTSA 
has observed that the horizontal bar of the underride device is less 
subject to docking impacts than the vertical bars because it is 
below most dock surfaces (and under a NHTSA proposal [a reference to 
the NHTSA's supplemental notice of rulemaking concerning rear impact 
guards (57 FR 252, January 3, 1992)] is even lower). Therefore, the 
final rule requires retroreflective material to be applied to the 
horizontal device, instead of the vertical ones. NHTSA believes that 
the original conspicuity material should have a long useful life on 
a large number of trailers, especially if it is applied to a 
recessed surface. However, NHTSA recognizes that routine damage, as 
a practical matter, may be unavoidable for some trailers as a 
consequence of their particular use. Therefore, [FMCSA] will 
consider the exclusion of conspicuity treatment from the rear 
underride device in any future rulemaking concerning trailer 
conspicuity requirements for vehicles subject to 49 CFR 393 Parts 
and Accessories Necessary for Safe Operation, and 49 CFR 396 
Inspection [,Repair,] and Maintenance.

The cross-reference to NHTSA's conspicuity requirements includes a 
reference to the specific paragraphs within FMVSS No. 108 concerning 
the locations for the conspicuity treatments. This does not, however, 
include an exemption to the requirement that motor carriers maintain 
the conspicuity material on the rear underride device.
    In addition to providing explicit guidance on trailer conspicuity, 
FMCSA amends Sec.  393.11 to codify certain regulatory guidance 
concerning the use of amber stop lamps, amber tail lamps, and optical 
combinations which would involve the use of amber tail lamps or amber 
stop lamps. Motor vehicles are required to be equipped with at least 
two red stop lamps and two red tail lamps. However, some motor carriers 
have expressed an interest in using additional stop lamps and/or tail 
lamps that are amber in color.
    Federal Motor Vehicle Safety Standard No. 108 does not allow amber 
as an alternate color for a tail lamp. In an August 23, 1990, 
interpretation to a manufacturer of lamps and reflectors, NHTSA stated 
that ``We have no intention of allowing amber as an alternate color for 
a tail lamp.'' In a December 10, 1991, interpretation to FHWA, NHTSA 
indicated that a combination amber turn signal and tail lamp is 
implicitly prohibited by FMVSS No. 108. NHTSA stated:

    When combined with an amber turn signal lamp, the intensity of 
an amber tail lamp might mask the turn signal operation. Because 
motorists are not used to seeing steady burning amber lamps on the 
rear of vehicles, amber taillamps could lead to momentary confusion 
of a driver following the trailer when the stop lamps are activated, 
thereby impairing the effectiveness of the stop signal. The presence 
of simultaneously burning amber and red taillamps could also create 
some confusion of a following driver approaching the trailer from 
around a corner to its rear. Thus we have concluded that a

[[Page 48013]]

combination amber turn signal and taillamp is implicitly prohibited 
by Standard No. 108.

FMCSA agrees that motorists are not use to seeing amber lamps used in 
conjunction with red lamps to signal that the vehicle is stopping and 
believes the FMCSRs should be amended explicitly to prohibit the use of 
amber tail lamps.
    To ensure the prohibition does not conflict with FMVSS No. 108, 
FMCSA reviewed NHTSA requirements. Section S5.1.3 of FMVSS No. 108 
prohibits the installation of supplementary lighting equipment that 
``impairs the effectiveness of lighting equipment required by this 
standard.'' Although the determination of impairment is initially that 
of the vehicle's manufacturer in certifying that the vehicle meets all 
applicable FMVSSs, NHTSA may review that determination and, if clearly 
erroneous, inform the manufacturer of its views.
    Because Sec.  393.11 cross-references FMVSS No. 108, FMCSA's 
regulatory guidance on the use of amber stop lamps and tail lamps is 
generally contingent upon a NHTSA determination as to whether or not 
the lamp impairs the effectiveness of other rear lamps. While 
certification by the vehicle manufacturer and subsequent review by 
NHTSA address the vehicle manufacturer's role in the safe operation of 
the CMV, a less complicated approach is needed to ensure that the 
FMCSRs are easy to understand, use, and enforce.
    Explicit guidance is provided to ensure that once a vehicle 
manufacturer certifies that a vehicle meets all applicable FMVSSs, the 
motor carrier does not modify it in a manner inconsistent with FMVSS 
No. 108. FMCSA is not aware of any vehicle manufacturers that use amber 
stop lamps or tail lamps as standard equipment. Consequently, the 
restriction would: (1) Discourage motor carriers from asking vehicle 
manufacturers to install amber tail lamps and/or stop lamps on vehicles 
as optional equipment, and (2) prohibit the motor carrier from 
installing or using such devices on its commercial motor vehicles.
    With regard to omissions in Table 1 in Sec.  393.11, FMCSA amends 
footnotes 4 through 10 to address inconsistencies with other sections 
of subpart B to part 393. In addition, the agency is correcting the 
listing for clearance lamps and reflex reflectors and to include metric 
units in describing the location of the required lamps and reflectors.
    The current listing for clearance lamps omits reference to footnote 
8 concerning pole trailers and does not include reference to the 
provision in FMVSS No. 108 (S5.1.1.9) for clearance lamps on boat 
trailers. Under FMVSS No. 108, a boat trailer with an overall width of 
2,032 mm (80 inches) or more is not required to be equipped with both 
front and rear clearance lamps provided an amber (to the front) and red 
(to the rear) clearance lamp is located at or near the midpoint on each 
side to indicate the extreme width of the trailer. This provision for 
clearance lamps on boat trailers is covered under a new footnote 17.
    The listings for reflex reflectors (front side) and side marker 
lamps (front) are revised to address an inconsistency between Sec.  
393.11 and FMVSS No. 108 (S5.1.1.15). Under FMVSS No. 108, a trailer 
that is less than 1,829 mm (6 feet) in length (including the trailer 
tongue) need not be equipped with front side marker lamps and front 
side reflex reflectors. This exception is covered under a new footnote 
16.
    FMCSA removes the last sentence in footnote 4, which requires that 
the rear side marker lamps be visible in the rearview mirror. This 
requirement is impractical and is inconsistent with FMVSS No. 108. 
Section 571.108 (S5.1.1.8) incorporates by reference the Society of 
Automotive Engineers recommended practice Clearance, Side Marker, and 
Identification Lamps, (SAE J592e, July 1972) which provides photometric 
standards. These standards cover visibility angles of 45 degrees left 
to 45 degrees right and 10 degrees up to 10 degrees down. In order for 
the rear side marker lamps to be visible in the rearview mirrors, the 
left to right angles would each have to be approximately 85 degrees. 
Because side marker lamps which meet the minimum standards contained in 
SAE J592e generally are not visible in the rearview mirror, the agency 
amends footnote 4.
    FMCSA makes editorial changes to footnotes 5 through 8 to improve 
the manner in which the requirements are presented. For instance, in 
footnote 5, the change makes it clear that converter dollies are only 
required to have one stop lamp and one tail lamp. The current wording, 
when combined with the legend at the end of Sec.  393.11, could be 
construed as requiring two stop lamps and two tail lamps.
    Amendments to footnotes 9 and 10 remove the requirements that 
projecting loads be equipped with lamps and reflectors during daylight 
hours. There is no apparent safety benefit for requiring lamps and 
reflectors on projecting loads during times when lamps are not required 
to be used.
    Footnote 15 is revised to incorporate language consistent with 
certain FMVSS No. 108 options--covered under S5.3.1.1.1, S5.3.1.4, 
S5.3.1.6--on the locations for clearance lamps.
Section 393.17--Lamps and Reflectors, Driveaway-Towaway Operations
    FMCSA amends the wording of the diagrams which illustrate the 
requirements of Sec.  393.17. The diagrams incorrectly reference 
Sec. Sec.  393.25(e) and 393.26(d); therefore, the sections are amended 
to reference Sec.  393.11, which covers the color of exterior lamps and 
reflective devices.
Section 393.19--Requirements for Turn Signaling Systems
    FMCSA revises Sec.  393.19 to make it more consistent with FMVSS 
No. 108 (S5.5.5). Paragraph S5.5.5 provides a concise standard that 
vehicle manufacturers must meet. To ensure consistency between FMVSS 
No. 108 and the FMCSRs, FMCSA adopts the NHTSA standard.
Section 393.20--Clearance Lamps to Indicate Extreme Width and Height
    FMCSA removes Sec.  393.20 because the requirements for the 
location and color of clearance lamps are provided in Table 1 of Sec.  
393.11. The exceptions concerning the mounting of clearance lamps 
currently contained in Sec.  393.20 is included under footnote 15 to 
Table 1. Illustrations comparable to those provided in Sec.  393.20 are 
already contained in Sec.  393.11.
Section 393.23--Lighting Devices to be Electric
    FMCSA amends Sec.  393.23 to incorporate terminology which is more 
consistent with current industry standards and practices. With the 
exception of temporary lamps used on projecting loads, lamps are 
required to be powered through the electrical system of the commercial 
motor vehicle. The title of Sec.  393.23 is revised to read ``Power 
supply for lamps'' and the reference to red liquid-burning lanterns is 
removed as obsolete.
Section 393.24--Requirements for Headlamps and Auxiliary Road Lighting 
Lamps
    FMCSA amends Sec.  393.24 to provide a more straightforward 
presentation of the requirements for the mounting of headlamps and 
auxiliary lamps, and to incorporate by reference SAE standards 
applicable to these lamps. Currently, Sec.  393.24 allows auxiliary and 
fog lamps to be used provided they meet ``the appropriate SAE standard 
for such lamps.'' FMCSA incorporates by

[[Page 48014]]

reference SAE standards J581 Auxiliary Upper Beam Lamps, July 2004, and 
J583 Front Fog Lamps, August 2004, for the purpose of establishing more 
specific performance requirements for such lamps. While auxiliary 
driving lamps and fog lamps are not required to be used, performance 
standards are being specified to ensure that the use of such devices 
does not decrease safety.
    A new paragraph is being added to address marking of headlamps. 
Paragraph S7.2 of FMVSS No. 108 requires the lens of each headlamp and 
beam contributor manufactured on or after December 1, 1989, to be 
marked. FMCSA amends the FMCSRs to include this requirement under Sec.  
393.24 to ensure that commercial motor vehicles are equipped with 
original or replacement headlamps which meet the requirements of FMVSS 
No. 108.
    Paragraph (d) of Sec.  393.24, Aiming and intensity, is being 
revised to reference FMVSS No. 108, and SAE standards J581 and J583. 
One of the SAE standards currently referenced in Sec.  393.24(d)--
Electric Headlamps for Motor Vehicles--was canceled by the SAE. The 
other SAE standard, J579 Sealed Beam Headlamp Units for Motor Vehicles, 
is not necessary given the cross-reference to FMVSS No. 108 and the 
incorporation by reference of SAE J581 and J583.
Section 393.25--Requirements for Lamps Other Than Headlamps
    To improve the clarity with which the requirements are presented, 
FMCSA revises Sec.  393.25 in its entirety. Section 393.25(a) provides 
a concise description of the mounting requirements for lamps. Paragraph 
(b), entitled ``Visibility,'' provides technically sound performance 
standards for all required lamps. Currently, Sec.  393.25(b) requires 
lamps to be mounted such that they are capable of being seen at 
distances up to 152.4 meters (500 feet) under clear atmospheric 
conditions during the period when lamps must be used as provided by 
Sec.  392.30. FMCSA determined that Sec.  392.30 duplicated State and 
local regulations and removed that requirement on November 23, 1994 (59 
FR 60319). Also, FMCSA believes the performance criteria for lamps are 
effectively addressed by Sec.  393.11 which cross-references FMVSS No. 
108. Lamps must, at a minimum, meet the requirements of FMVSS No. 108 
in effect on the date of manufacture of the vehicle. FMVSS No. 108 
specifies the minimum and maximum photometric output values for 
required lamps. Vehicles not subject to FMVSS No. 108 on the date of 
manufacture are required to meet the visibility requirements specified 
in the SAE standards for incorporation by reference under Sec.  
393.25(c).
    FMCSA deletes Sec.  393.25(d), entitled ``Certification and 
markings,'' to make the FMCSRs consistent with FMVSS No. 108. With the 
exception of headlamps and beam contributors, FMVSS No. 108 does not 
require lamps to be marked. Manufacturers are responsible for ensuring 
that their products meet the applicable requirements of FMVSS No. 108, 
but the lamps do not need to be marked by the manufacturer to indicate 
that the device meets the standards. In this case, Sec.  393.25(d) sets 
in-service requirements for lamps which are more stringent than the 
manufacturing standards set by the NHTSA. The removal of Sec.  
393.25(d) corrects this inconsistency.
    FMCSA amends Sec.  393.25(e), entitled ``Lighting devices to be 
steady-burning,'' and Sec.  393.25(f), entitled ``Stop lamp 
operation,'' to provide more concise statements of the requirements of 
each. The FMCSA is allowing exceptions for the use of amber warning 
lamps which meet SAE J595, Directional Flashing Optical Warning Devices 
for Authorized Emergency, Maintenance, and Service Vehicles, January 
2005, SAE J845, Optical Warning Devices for Authorized Emergency, 
Maintenance, and Service Vehicles, May 1997, or SAE J1318 Gaseous 
Discharge Warning Lamp for Authorized Emergency, Maintenance, and 
Service Vehicles, May 1998. All of these SAE recommended practices are 
incorporated by reference. Although the notice of proposed rulemaking 
preceding this final rule would have prohibited the use of certain 
Class 1 warning devices, FMCSA no longer believes such a prohibition is 
necessary. Several commenters indicated amber colored Class 1 warning 
devices are commonly used on certain commercial motor vehicles and 
there has been no adverse impact on safety. Adding these devices to the 
list of exceptions prevents confusion about the applicability of Sec.  
393.25(e).
    FMCSA revises Sec.  393.25(f) to eliminate a regulatory 
inconsistency between Sec. Sec.  393.25(f) and 393.49 and to simplify 
the wording of the requirements. Currently, Sec.  393.25(f) states that 
stop lamps on a towing vehicle need not be actuated when service brakes 
are applied to the towed vehicle(s) only. This provision is 
inconsistent with Sec.  393.49, entitled ``Single valve to operate all 
brakes.'' When a combination vehicle includes a trailer that is 
required to be equipped with brakes, the braking system must be 
arranged so that a single valve controls the brakes on the towing unit 
and the towed unit. Because the FMCSRs do not allow the towing unit to 
operate without service brakes, and a single valve is required to 
operate all the brakes on the combination, the current wording of Sec.  
393.25(f) is inconsistent with Sec.  393.49. The revision to Sec.  
393.25(f) includes language from FMVSS No. 108, S5.5.4, concerning stop 
lamp operation, to ensure consistency between the FMCSRs and the 
FMVSSs.
Section 393.26--Requirements for Reflectors
    Consistent with the amendments to Sec.  393.25, FMCSA is revising 
Sec.  393.26 in its entirety. FMCSA amends Sec.  393.26(a) concerning 
the mounting of reflectors, to provide guidelines comparable to those 
for Sec.  393.25(a). Paragraph (b) is revised to include a requirement 
that reflex reflectors on projecting loads, vehicles transported in 
driveaway-towaway operations, converter dollies, and pole trailers meet 
SAE J594--Reflex Reflectors, December 2003. The SAE recommended 
practice is incorporated by reference.
    The current requirement for certification and marking under Sec.  
393.26(c) is being removed to make the FMCSRs consistent with FMVSS No. 
108. FMVSS No. 108 does not require that reflectors be marked by the 
manufacturer to indicate that the device meets the standards. Paragraph 
(c) would then be used to incorporate American Society for Testing and 
Materials (ASTM) D4956-04, Standard Specification for Retroreflective 
Sheeting for Traffic Control, as the minimum standard for reflective 
tape used in lieu of reflex reflectors. Retroreflective sheeting that 
conforms to the ASTM standard would generally meet the requirements of 
FMVSS No. 108, S5.1.1.4, concerning the use of reflective tape in lieu 
of reflex reflectors. The performance of the reflective sheeting as 
installed on the vehicle must meet the visibility requirements under 
SAE J594, Reflex Reflectors, December 2003.
    Paragraph (d) is being revised to more clearly state that 
reflective surfaces or materials other than those required by Sec.  
393.11 may be used in addition to, but not in lieu of, the required 
reflective devices.
Sections 393.27, 393.28, 393.29, 393.31, 393.32, 393.33--Regulations on 
Electrical Wiring
    FMCSA incorporates by reference in Sec.  393.28, SAE J1292--
Automobile, Truck, Truck-Tractor, Trailer, and Motor Coach Wiring, 
October 1981, which covers basic aspects of performance, operating 
integrity, and service. Section

[[Page 48015]]

393.28 is being renamed ``Wiring systems.'' The guidelines contained in 
J1292 effectively cover the requirements currently addressed by Sec.  
393.27, Wiring specifications; Sec.  393.28, Wiring to be protected; 
Sec.  393.29, Grounds; Sec.  393.31, Overload protective devices; Sec.  
393.32, Detachable electrical connections; and Sec.  393.33, Wiring, 
installation. Among the specific topics addressed by the SAE standard 
are insulated cables; conductor termination; conductor splicing; 
conductor grouping; wire assembly construction; wire assembly 
installation and protection; and wiring overload protective devices. 
The SAE standard for incorporation provides a concise presentation of 
those aspects of commercial vehicle electrical systems that should be 
addressed by the FMCSRs. Sections 393.27, 393.29, 393.31, 393.32 and 
393.33 are being removed.
    The incorporation by reference removes certain design restrictive 
language from Sec.  393.28(a)(5) concerning terminals or splices above 
the fuel tank. FHWA received petitions from the Ford Motor Company, 
Freightliner Corporation, and the Motor Vehicle Manufacturers 
Association (now the American Motor Vehicle Manufacturers Association) 
requesting an amendment to Sec.  393.28(a)(5), which was adopted in the 
December 7, 1988, final rule (53 FR 49380). The petitions are available 
for review in the docket. Each of the petitions pointed out that use of 
the word ``terminal'' combined with ``above'' created ambiguity with 
respect to the proximity of electrical wiring to the fuel tanks. 
Electrical terminals performing various functions, from battery 
terminals (Ford Motor Co.) to relays and switches (Freightliner 
Corporation), are mounted above the fuel tanks. In some instances these 
switches or relays with terminals are mounted 203 mm (8 inches) or more 
above the fuel tank or on the frame rail (in the case of Freightliner 
and Daimler-Benz power units). In the case of Ford power units, the 
fuel tank is specifically designed for battery installation.
    The notice of proposed rulemaking that preceded the final rule 
would have prohibited wiring from being adjacent to any part of the 
fuel system (52 FR 5892, February 26, 1987). The wording in the final 
rule was less restrictive than the proposed language and focused 
specifically on terminals and splices. FMCSA agrees with the 
petitioners, however, that Sec.  393.28(a)(5) is still unnecessarily 
restrictive. FMCSA's decision to incorporate by reference criteria that 
effectively and safely address the issue of wiring around the fuel 
system of commercial motor vehicles resolves the petitioners' concerns.
    FMCSA includes an exception to the incorporation by reference for 
jumper cable plugs and receptacles, and circuit protection requirements 
for trailers. Jumper plugs and receptacles need not conform to SAE J560 
Primary and Auxiliary Seven Conductor Electrical Connector for Truck-
Trailer Jumper Cable, which provides the minimum requirements for 
primary and auxiliary jumper cable plugs and receptacles for the truck-
trailer and converter dolly jumper cable systems. TTMA indicated in its 
comments most trailers are equipped with an SAE J560 receptacle, but 
they may also have a modified International Standards Organization 
(ISO) 3731 receptacle, while others may have a 13-conductor Cole-Hersee 
receptacle. FMCSA agrees with TTMA and believes safety would not be 
compromised by allowing flexibility.

Subpart C--Brakes

Section 393.40--Required Brake Systems
    FMCSA revises Sec.  393.40 in its entirety to present more clearly 
the requirements contained therein. Generally, vehicles that have been 
maintained to continue compliance which meet the manufacturing 
standards applicable at the time of the vehicle is built, will not be 
affected by the revisions. Hydraulic braked and air braked vehicles are 
required to meet the requirements of FMVSS Nos. 105 and 121, 
respectively, in effect at the time of manufacture. The service, 
parking, and emergency brake requirements for vehicles which were not 
subject to either of the FMVSS brake regulations is provided by 
references to other applicable sections in subpart C and by the 
requirements currently found under Sec.  393.40(b)(2) and (c).
    With regard to FMVSS No. 105, FMCSA notes that between September 1, 
1975, and October 12, 1976, the standard was applicable to trucks and 
buses. However, from October 12, 1976, to September 1, 1983, it covered 
only passenger cars and school buses. From 1983 to the present, the 
standard has applied to trucks and buses. For the purposes of Sec.  
393.40, FMCSA will use September 2, 1983, as the date for determining 
which hydraulic-braked vehicles must be maintained to meet certain 
requirements under FMVSS No. 105.
    There could be some benefit in requiring vehicles manufactured 
between September 1975 and October 1976 to meet the requirements of 
FMVSS No. 105 in effect on the date of manufacture. However, the number 
of these older vehicles still in operation is relatively small, and the 
brake requirements under part 393 to which these vehicles would 
continue to be subject should ensure safety of operation.
Section 393.41--Parking Brake System
    The December 7, 1988, final rule on part 393 was intended to make 
the parking brake requirements of the FMCSRs consistent with the 
parking brake requirements of FMVSS Nos. 105 and 121. FMCSA has since 
determined that additional changes are necessary. The current language 
only covers vehicles with air brakes manufactured on or after March 7, 
1990, which are subject to FMVSS No. 121. The wording implies that all 
non-air braked vehicles, irrespective of the date of manufacture, and 
air braked motor vehicles manufactured prior to that date are not 
required to be equipped with parking brakes.
    Prior to the 1988 amendment, Sec.  393.41 required that every 
singly driven motor vehicle and every combination of motor vehicles 
shall at all times be equipped with a parking brake system adequate to 
hold the vehicle or combination on any grade on which it is operated 
under any condition of loading on a surface free from ice or snow. 
FMCSA considers the parking brake requirements in effect prior to the 
1988 amendment to provide a more straightforward standard that is 
easier for the industry and State officials to understand.
    FMCSA revises Sec.  393.41 to state clearly that every self-
propelled commercial motor vehicle (i.e., trucks, truck-tractors and 
buses) and every combination of commercial motor vehicles must be 
equipped with a parking brake system adequate to hold the vehicle or 
combination on any grade on which it is to be parked and under any 
condition of loading, on a surface free from ice or snow. Commercial 
motor vehicles which were subject to the parking brake requirements of 
FMVSS Nos. 105 or 121 at the time of manufacture are required to 
maintain the parking brake systems to meet those standards. Motor 
vehicles which were not subject to either of the FMVSS parking brake 
requirements must meet the requirements currently found at Sec.  
393.41(b) and (c).
    The revisions to Sec.  393.41 also address a petition for 
rulemaking from International Transquip Industries, Incorporated (ITI) 
asking FMCSA to clarify the applicable requirements for air-applied, 
mechanically-held, parking brakes. The petition is available for review 
in the docket. The ITI

[[Page 48016]]

manufactures an air brake system which includes an air-applied, 
mechanically-held parking brake. The parking brake application is 
initiated by exhausting air off the supply line. When the control valve 
senses the supply line pressure drop, it ports air from either the 
primary or secondary reservoirs at a controlled pressure to the brake 
chambers resulting in an application of the brakes. The same supply 
line pressure signal activates a synchronizing device which engages the 
mechanical pistons immediately after the brakes have been applied.
    Section 393.41(b) requires that the parking brake be capable of 
being applied at all times by either the driver's muscular effort, or 
by spring action, or by other energy. In the case of ``other energy,'' 
the accumulation of such energy must be ``isolated from any common 
source and used exclusively for the operation of the parking brake.'' 
This wording has been in effect since 1962 and could be construed as 
requiring a separate reservoir for air-applied, mechanically-held 
parking brakes. Such a requirement is inconsistent with FMVSS No. 121.
    On August 9, 1979, NHTSA amended FMVSS No. 121 to allow the 
application of the parking brakes by means of service brake air if: (1) 
The application could be made when a failure exists in the service 
brake system, and (2) the parking brake is held in the applied position 
by mechanical means (44 FR 46850). Prior to this amendment, an air-
applied, mechanically-held parking brake was required to be applied by 
a separate reservoir. The revision of Sec.  393.41(b) includes a cross-
reference to the parking brake requirements of FMVSS No. 121, thus 
eliminating any inconsistencies.
    For air braked vehicles which were not subject to FMVSS No. 121 at 
the time of manufacture, Sec.  393.41 would continue to allow the use 
of air-applied, mechanically-held parking brake systems applied by a 
separate reservoir. The motor carrier would have the option of 
modifying the brake system to meet FMVSS No. 121. Air-applied, 
mechanically-held parking brakes which are designed to operate without 
a separate reservoir could be used if the conditions specified in FMVSS 
No. 121 are met.
Section 393.42--Brakes Required on All Wheels
    The agency is revising Sec.  393.42(b)(3) to clarify the exceptions 
for lightweight trailers and to address brake requirements on 
housemoving dollies, three-axle dollies steered by a co-driver, and 
similar dollies and trailers used for transporting extremely large and 
heavy loads at low speeds.
    As part of the January 27, 1987, final rule on front wheel brakes, 
FMCSA amended the exemption for brakes on lightweight trailers (52 FR 
2801). Prior to the amendment, full trailers, semi-trailers, or pole 
trailers with a gross weight of less than 1,360 kg (3,000 pounds) were 
not required to have brakes provided the weight of the trailer did not 
exceed 40 percent of the weight of the towing unit. The 1987 amendment 
replaced the term ``gross weight'' with ``GVWR'' or gross vehicle 
weight rating.
    While the change to GVWR has certain benefits in terms of applying 
the regulation to situations in which it is not convenient to weigh the 
trailer, the amendment did not adequately address concerns about 
stability and control during braking for trailers that have a GVWR 
greater than 1,361 kg (3,000 pounds), but an actual or gross weight 
less than 1,361 kg when lightly loaded. Under certain circumstances, 
trailers of this weight range may be overbraked resulting in wheel 
lockup or skidding when the trailer is lightly loaded. FMCSA believes 
Sec.  393.42 should be amended to make reference to the gross weight. 
Trailers covered under the current reference to GVWR are covered under 
the revised exemption provided the vehicle is not loaded beyond the 
manufacturer's weight rating. Trailers with a GVWR in excess of 1,361 
kg (3,000 pounds) would only be covered by the exemption on those 
occasions when the gross weight of the trailer is 1,361 kg (3,000 
pounds) or less. The language would help to provide a performance-based 
criterion that is easier to understand and enforce.
    Although the exemption concerning lightweight trailers never 
specifically addressed converter dollies, the issue of overbraking on 
unladen converter dollies has been the subject of several requests for 
interpretation of Sec.  393.42(b). Converter dollies are generally 
designed to carry loads of approximately 9,072 kg (20,000 pounds) with 
a brake system sized for the fully loaded condition. While the GVWR is 
greater than 1,360 kg (3,000 pounds) the unladen weight is usually 
1,360 kg or less. When towed behind another motor vehicle, the unladen 
converter dolly is overbraked, with the application of the service 
brakes causing wheel lock-up or skidding.
    In 1990, NHTSA's Vehicle Research and Test Center (VRTC) conducted 
tests to evaluate the braking and stability of a bobtail truck tractor 
towing an unladen converter dolly. Both the truck tractor and the 
converter dolly were equipped with ABS that could be deactivated. The 
truck tractor was also equipped with an automatic front-axle limiting 
valve (ALV) and a bobtail proportioni