[Federal Register Volume 64, Number 64 (Monday, April 5, 1999)]
[Rules and Regulations]
[Pages 16358-16359]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-8186]


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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571


Federal Motor Vehicle Safety Standards; Lamps, Reflective Devices 
and Associated Equipment

AGENCY: National Highway Traffic Safety Administration (NHTSA), DOT.

ACTION: Interpretive rule.

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SUMMARY: This document sets forth our interpretation of the location 
requirements for identification and clearance lamps mounted on the rear 
of trucks and trailers whose overall width is more than 2032 mm (80 
in.). Federal Motor Vehicle Safety Standard No. 108 requires that 
identification lamps be mounted as close to the top of a vehicle as 
practicable. The identical requirement applies to clearance lamps, 
except when the rear identification lamps are mounted at the extreme 
height of the vehicle. In the past, we have stated that the 
manufacturer may make the initial determination as to whether it is 
practicable to mount these lamps near the top of a vehicle, and that it 
has been our enforcement policy to accept the manufacturer's 
determination of practicability unless that decision appears clearly 
erroneous. Under this approach, identification lamps on many vehicles, 
especially van-type trailers, have been mounted on the lower sill below 
the rear doors under various conditions, even on vehicles where the 
header was up to 3 inches wide. Our enforcement policy was based in 
part on the unavailability of narrow lamps. However, narrow lamps are 
now readily available. Effective on the publication of this 
interpretive rule, we interpret Standard No. 108 to require 
manufacturers to satisfy an objective standard of practicability; i.e., 
if, under all the circumstances, it would be practicable to locate 
lamps above the rear doors, the manufacturer must do so. We will no 
longer defer to a manufacturer's subjective determination of 
practicability.

DATES: Effective April 5, 1999.

FOR FURTHER INFORMATION CONTACT: Taylor Vinson, Office of Chief 
Counsel, NHTSA (Phone: 202-366-5263; FAX: 202-366-3820).

SUPPLEMENTARY INFORMATION:

Requirements of Federal Motor Vehicle Safety Standard No. 108 for 
the Location of Identification and Clearance Lamps on Large Trucks 
and Trailers

    Table I of Federal Motor Vehicle Safety Standard No. 108, Lamps, 
Reflective Devices and Associated Equipment, requires trucks and 
trailers whose overall width is 2032 mm (80 inches) or more to be 
equipped with a rear lighting system that includes three red 
identification lamps and two red clearance lamps. Table II specifies 
that the identification lamps are to be mounted on the rear ``as close 
as practicable to the top of the vehicle at the same height, as close 
as practicable to the vertical centerline.'' Table II also requires 
that the clearance lamps shall be mounted on the rear ``to indicate the 
overall width of the vehicle, one on each side of the vertical 
centerline, at the same height, and as near the top thereof as 
practicable.'' However, clearance lamps need not be located near the 
top ``when the rear identification lamps are mounted at the extreme 
height of a vehicle,* * *'' S5.3.1.4).
    In general, location requirements specified by Standard No. 108 for 
motor vehicle lamps and reflectors are expressed in terms of 
practicability. Under this approach, the required lighting equipment 
can be installed without unduly restricting the design of vehicles.

Past Policy Regarding the Meaning of ``Practicability'' With 
Respect to the Upper Mounting Location for Identification and 
Clearance Lamps

    In 1968, when Standard No. 108 became effective for wide vehicles, 
lighting technology had not advanced to the level where it is today, 
and, in order to provide the required photometric performance, 
generally lamps were somewhat larger than lamps that are now 
commercially available. Manufacturers advised us that, in their 
opinion, it would not be practicable to mount the lamps on the rear 
header of some vehicles. Rather than make individual practicability 
assessments in an enforcement context, we advised the industry that we 
would not contest manufacturers' decisions to mount identification and 
clearance lamps below the cargo doors, on an approximate horizontal 
plane with other rear lamps, except where the manufacturer's decision 
was clearly erroneous.
    This deferential approach originated as a matter of enforcement 
policy. Indeed, it was first articulated in a June 18, 1981 letter to 
the Division of State Patrol of the Wisconsin DOT from Francis 
Armstrong, who was the Director of NHTSA's Office of Vehicle Safety 
Compliance. Over the years this enforcement policy was restated in 
several letters signed by NHTSA's Chief Counsels.
    However, over the years, narrow lamps have become available for use 
on trucks and trailers with relatively narrow headers. Since it appears 
that it is now ``practicable'' to locate clearance and identification 
lamps on or above such headers, we decided to review the issue and 
reconsider our earlier enforcement policy.
    As part of our review, we conducted a field survey in which we took 
photographs and measured rear lighting configurations of several 
typical trailers. The photographs showed that some trailer 
manufacturers are locating identification and clearance lamps on the 
lower sill of many trailer models, even though there is sufficient 
space to

[[Page 16359]]

put those same lamps in the header area.

NHTSA's Preliminary Evaluations and Manufacturers' Responses

    Based on the field survey information, we opened Preliminary 
Evaluations and sent information requests to eight van trailer 
manufacturers in November 1997. The manufacturers responded that each 
produces some models with identification and clearance lamps on the 
lower sill. Of a total production of these manufacturers totaling over 
440,000 vehicles, the number with identification lamps located on the 
lower sill was approximately 225,000, or over half.
    The manufacturers justified this location as one permitted by 
previous NHTSA letters and as representing ``common industry 
practice.'' They also argued that conspicuity treatment provides a 
sufficient delineation of vehicle size. Addressing practicability, the 
manufacturers contended that smaller lamps such as those using light-
emitting diodes (LEDs) could not be installed on narrow headers because 
of the lack of availability of LEDs, the difficulty of wiring them in a 
narrow area, and structural problems that could arise if the trailers 
were redesigned to accommodate lamps at the top. Some manufacturers 
argued that the lower sill location is needed to provide a surface that 
is large enough and rigid enough for the lamps. The respondents may not 
have been aware of very narrow lamps. Some incandescent lamps as narrow 
as 17.3 mm (0.68 in.) and some LED lamps as narrow as 22.4 mm (0.88 
in.) are now available.
    One manufacturer also commented that lamps placed on the lower sill 
are more conveniently replaced when replacement becomes necessary. 
However, replacement would be less frequent with the use of reliable, 
long-life LED lamps. Another mentioned that slim-line lamps do not 
dissipate heat as effectively as larger incandescent lamps. However, 
LED lamps emit only a low level of heat. Another mentioned that narrow 
lamps do not seal out moisture as effectively, without also noting that 
narrow lamps are available that are permanently sealed. None of the 
manufacturers indicated that they planned to change the existing 
location of their clearance or identification lamps.

Canada's Rear Identification and Clearance Lamp Location 
Requirements

    On November 10, 1996, Canadian Motor Vehicle Safety Standard No. 
108 was amended to require that identification and clearance lamps be 
mounted above or on the rear doors when the header extends at least 25 
mm (1 in.) above the rear doors. When the header extends less than 25 
mm, the lamps may be mounted above, on, or below the rear doors. Since 
then, Canada has enforced this standard on trucks engaged in commerce 
within its borders, including those manufactured in the United States 
that operate in Canada. Some of these U.S. manufacturers have complied 
with Canada's upper location requirements, but have nevertheless 
continued to locate lamps on the lower sill of their trailers 
manufactured for use in the United States which have a rear door and 
header assembly identical to their counterparts sold for use in Canada. 
The Canadian practice objectively supports the view that it would have 
been ``practicable'' to locate the lamps at the top of the U.S. 
vehicles.

Truck Trailer Manufacturer's Association's (TTMA) Recommended 
Practice for Rear Identification and Clearance Lamp Placement

    TTMA restates NHTSA's past approach on practicability in its 
recommendations to its members on location of rear identification and 
clearance lamps. It goes on to recommend that the lamps be on the 
header when the header extends at least 50 mm (2 in.) above the rear 
doors when there is a flat space of at least 25 mm (1 in.).

NHTSA's New Interpretive Rule

    After reviewing the matter, we have concluded that clearance and 
identification lamps that meet the photometric requirements of Standard 
No. 108, and are of a size permitting mounting on the header above the 
rear doors of most trailers and trucks, are available in the 
marketplace. The prior enforcement policy has, in practice, deferred to 
manufacturers who exercised their discretion to decide whether to mount 
these lamps above the rear doors. This approach has not assured that 
the safety purposes of the standard are achieved. The responses to 
NHTSA's information requests demonstrate that many U.S. manufacturers, 
including some of the largest trailer manufacturers, have placed, and 
are continuing to place, identification and clearance lamps below the 
rear doors, notwithstanding the fact that the ability of many of these 
same manufacturers to comply with the new Canadian requirements 
demonstrates that it is now practicable to mount identification and 
clearance lamps on the rear header in most instances.
    As reflected by the responses to our information requests, many 
manufacturers have taken advantage of the deference conferred by our 
longstanding enforcement policy in deciding where to locate these 
lamps. In recognition of this practice, we have decided that it would 
be preferable to provide notice that the prior policy has been changed 
before bringing enforcement actions against such manufacturers without 
providing notice that the prior policy has been changed. Accordingly, 
we are publishing this interpretation of the requirement in Table II of 
Standard No. 108 that rear clearance lamps and identification lamps 
must be located ``as near the top thereof as practicable'' to make it 
clear that, henceforth, manufacturers will be required to satisfy an 
objective standard of practicability, i.e., if under all the 
circumstances it would be practicable to locate the identification and 
clearance lamps above the rear doors, the manufacturer must do so. 
Moreover, based on the experiences of manufacturers who have been able 
to comply with the Canadian requirements, NHTSA will presume that it is 
practicable to locate lamps on the header of a vehicle when the header 
extends at least 25 mm (1 in.) above the rear doors.
    This interpretive rule is effective as of its publication in the 
Federal Register. However, as a matter of enforcement discretion, we do 
not intend to bring enforcement actions based on this interpretive rule 
immediately. This will be addressed separately.

    Authority: 49 CFR 1.50 and 501.8(d)(5).

    Issued on: March 30, 1999.
Frank Seales, Jr.,
Chief Counsel.
[FR Doc. 99-8186 Filed 4-2-99; 8:45 am]
BILLING CODE 4910-59-P