[Federal Register Volume 59, Number 145 (Friday, July 29, 1994)]
[Unknown Section]
[Page 0]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 94-18517]


[[Page Unknown]]

[Federal Register: July 29, 1994]


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DEPARTMENT OF TRANSPORTATION
[Docket No. 94-65; Notice 1]

 

General Motors Corporation; Receipt of Petition for Determination 
of Inconsequential Noncompliance

    General Motors Corporation (GM) of Warren, Michigan, has determined 
that some of its vehicles fail to comply with 49 CFR 571.108, Federal 
Motor Vehicle Safety Standard (FMVSS) No. 108, ``Lamps, Reflective 
Devices, and Associated Equipment,'' and has filed an appropriate 
report pursuant to 49 CFR Part 573, ``Defect and Noncompliance 
Reports.'' GM has also petitioned to be exempted from the notification 
and remedy requirements of 49 U.S.C. Chapter 301--``Motor Vehicle 
Safety'' on the basis that the noncompliance is inconsequential as it 
relates to motor vehicle safety.
    This notice of receipt of a petition is published under 49 U.S.C. 
30118 and 30120 (formerly Section 157 of the National Traffic and Motor 
Vehicle Safety Act (15 U.S.C. 1417)) and does not represent any agency 
decision or other exercise of judgment concerning the merits of the 
petition.
    Figure 10 of FMVSS No. 108, referenced at S5.1.1.27(a)(3), lists 
the photometric requirements for center high-mounted stop lamps 
(CHMSLs).
    GM produced two different populations which do not meet the 
photometric requirements listed in Figure 10. The first population of 
vehicles, approximately 23,695 Cadillac Deville and Deville Concours 
produced between the start of the 1994 model year until November 19, 
1993, had the CHMSL ``framed'' in the rear window by a 27 mm high 
opening in the blackout paint at the lower edge of the rear window. A 
vertical shift in the installed position of the rear window, compounded 
by build variation, caused the painted frame around the CHMSL on these 
vehicles to obscure the photometric performance at the 5D line.
    The second population of vehicles, approximately 65,403 Cadillac 
Deville and Deville Concours produced from November 19, 1993 until May 
4, 1994, had a narrower painted ``frame'' around the CHMSL in the rear 
window. Due to an engineering change, the blackout paint ``frame'' was 
narrowed by 5 mm to a width of 22 mm. The shift in installed position 
and build variation noted above accounted for the obscuration of the 5D 
line on some of these vehicles. Other vehicles within this second 
population experience obscuration of the 10U line as a result of the 
build variation. In no case does a vehicle experience obscuration of 
both the 5D and 10U lines.
    GM supports its petition for inconsequential noncompliance with the 
following. GM also submitted diagrams and tables to support its 
petition which are available for review in the NHTSA docket.

    GM performed a dimensional analysis on a 51-vehicle sample to 
determine where the paint opening on the rear glass was in relation 
to the CHMSL. (Note that no CHMSL could be obscured at both the top 
and bottom by the paint line.) For those vehicles with the CHMSL 
obscured at the bottom of the lamp, the analysis, which approximates 
a normal distribution, indicated that 1.5 percent of the entire 
population of vehicles, or approximately 1,336 vehicles, could 
experience sufficient obscuration to render the vehicles out of 
compliance with FMVSS 108, with a 4.6 mm worst case infringement at 
the bottom of the CHMSL. However, a photometric test conducted on a 
CHMSL with a 4.6 mm mask at the bottom of the lamp established that 
for the rest points that fell on and below horizontal, i.e., for the 
points on the H and 5D lines, photometric output exceeds FMVSS 108 
requirements by an average of 75 percent. * * * Even on the 5D line, 
all five test points were within 20 percent of FMVSS 108, with the 
worst performance at 5D-5R, where the tested value was 23.0 candela, 
or 82 percent of the 25.0 candela requirement.
    As for those vehicles with the CHMSL obscured at the top of the 
lamp, the sample suggests that 15 percent of the second population 
described above, or 9,810 vehicles, could be obscured to the point 
that they would fail to comply with FMVSS 108, with a worst case 
infringement at the top of the CHMSL of 4.5 mm. However a 
photometric test on a CHMSL with a 4.5 mm mask at the top of the 
lamp demonstrated that while test values on the 10U line fall below 
required levels, the lamp provides approximately 75 percent more 
light output above horizontal (at the 5U and 10U lines combined) 
than required by FMVSS 108. (Photometric output of the obscured lamp 
as a whole approximated 33 percent more than FMVSS 108 
requirements.) * * *
    To determine the extent of the noncompliance for those vehicles 
obscured at the top of the CHMSL, GM plotted data from a series of 
photometric tests of 10U-V (the worst performing test point), with 
varying degrees of obscuration, against performance to the FMVSS 108 
requirement. The result approximates a linear function of 
obscuration versus photometric output, and suggests that subject 
CHMSLs obscured less than 3.07 mm will fall within 20 percent of the 
values listed in FMVSS 108. * * * Applying the distribution 
determined from GM's 51-vehicle sample to that, approximately 76 
percent, or 7,456 of the 9,810 vehicles described above, will 
provide photometric output within 20 percent of the FMVSS 108 
requirements at 10U.
    As acknowledged in NHTSA's notices granting other similar 
Petitions for Determination of Inconsequential Noncompliance, a 
change in luminous intensity of approximately 25 percent is required 
before the human eye can detect a difference between two lamps. (See 
e.g., Notice granting Petition by Subaru of America (56 Fed. Reg. 
59971); and Notice granting Petition by Hella, Inc. (55 Fed. Reg. 
37601, at 37602).) Given this, the 7,456 vehicles obscured less than 
3.07 mm at the top of the CHMSL, as well as the 1, 336 vehicles 
obscured at the bottom of the lamp, do not compromise motor vehicle 
safety since the noncompliance is imperceptible to the naked eye and 
the overall light at the outer zones (H & 5D; 5U & 10U) exceeds the 
FMVSS requirements.
    Although the degradation in light output for the 2,354 remaining 
vehicles would likely be discernible in a subjective side-by-side 
comparison with a conforming lamp, visible light is still emitted at 
the 10U line. Moreover, GM's photometric analysis indicates that 
even with a worst case obscuration of the 10U line, the 16 candela 
required light output at 10U-V is supplied at 8U-V. Given that and 
the location of the CHMSL on the subject vehicles, these CHMSLs 
perform their intended function in a manner virtually 
indistinguishable from CHMSLs on other vehicles that fully comply 
with FMVSS 108, as demonstrated below.
    The specified ranger of required photometric output for CHMSLs 
from 10U to 5D was developed from SAE J186a and is presumably 
intended to allow manufacturers latitude in locating CHMSLs for the 
myriad of vehicle designs, while assuring that sufficient light is 
available to signal drivers of following vehicles. For example, the 
10U photometric angle helps to assure that drivers of large vehicles 
(such as medium and heavy duty trucks), perceive a preceding 
vehicle's CHMSL signal, regardless of the size of that vehicle or 
the CHMSL's mounting location.
    However, the Cadillac CHMSL is mounted relatively high in 
relation to other passenger vehicles on the road, and is located in 
the passenger compartment, not on the deck lid. Therefore, the light 
emitted from the Cadillac CHMSL at the upward-most photometric 
angles is not as critical as light at those same angles emitted from 
vehicles with CHMSLs located rearward and closer to the ground.
    To illustrate this point, GM compared the Cadillac CHMSL to the 
CHMSL on the Mazda Miata. The Miata sits comparatively low to the 
ground, and its CHMSL is mounted low on the deck lid. After 
determining that the 16 candela photometric output required by FMVSS 
108 at 10U-V is provided by the Cadillac CHMSL with a worst case 
intrusion at 8U, GM overlaid the mounting location and 10U line of 
the Mazda Miata on a drawing of the Cadillac CHMSL and 8U line, 
placing the rear of the vehicles at the same location. * * * The 
result shows that the 8U and 10U lines cross 37.4 feet behind the 
vehicles and 9.3 feet above the ground; until that point, the 
Cadillac CHMSL provides more light to the extreme up positions than 
does the fully compliant Miata CHMSL.
    GM then overlaid on the drawing of the Cadillac and Miata CHMSLs 
the average eye ellipse location for heavy duty trucks (cab over) 
and medium duty trucks, which are 7.7 feet and 6.8 feet from ground, 
respectively. * * * The fact that these eye-ellipse locations fall 
well below the 9.3 feet intersection point of the Cadillac CHMSL 8U 
line and the Miata CHMSL 10U line demonstrates that the Cadillac 
CHMSL provides sufficient usable light to all following drivers. 
That is, because GM designed the subject vehicles with a high and 
forward CHMSL mounting location, drivers sitting at the highest 
positions from the road will see the photometric output intended by 
the Standard for the upward-most angles, regardless of (worst case) 
obscuration of the lamp. The Cadillac CHMSL actually provides a 
greater area of visible light than a vehicle with a fully compliant 
lamp that is mounted lower and rearward.
    There are vehicles with fully compliant CHMSLs, at mounting 
locations approximating that of the Cadillac, that cast more light 
in the upper extreme areas behind the vehicle. However, * * * a 
compliant CHMSL (mounted at the same location as the Cadillac CHMSL) 
will provide only an additional triangular area six feet in length 
and eleven inches high of potentially usable light, starting 20 feet 
behind the vehicle. This small area is only visible to drivers of 
the largest vehicles. Given that and negligible decrease of light 
emitted by the Cadillac CHMSL, GM believes that the Cadillac CHMSL 
will perform its intended function effectively identical to fully 
compliant CHMSLs mounted at the same location. Furthermore, as 
demonstrated above, the Cadillac CHMSL provides more light at the 
extreme up angles than other fully compliant CHMSL mounted lower and 
reward. These factors, together with the small number of Cadillacs 
involved, support GM's belief that the CHMSLs at issue here will not 
have an adverse affect on motor vehicle safety.
    The CHMSLs otherwise meet all FMVSS 108 requirements, and the 
photometric output of the stop lamps, which are supplemented by the 
CHMSL, far exceeds FMVSS 108 minimum requirements.
    GM is not aware of any accidents, injuries, owner complaints or 
field reports related to this issue.
    General Motors believes that the noncompliance that results from 
a small obstruction of the CHMSL by blackout paint on the rear 
window is inconsequential as it relates to motor vehicle safety. In 
consideration of the foregoing, General Motors petitions that it be 
exempted from the recall and remedy provisions of the Act for this 
specific noncompliance with FMVSS 108.

    Interested persons are invited to submit written data, views, and 
arguments on the petition of GM, described above. Comments should refer 
to the docket number and be submitted to: Docket Section, National 
Highway Traffic Safety Administration, Room 5109, 400 Seventh Street, 
SW., Washington, D.C., 20590. It is requested but not required that six 
copies be submitted.
    All comments received before the close of business on the closing 
date indicated below will be considered. The application and supporting 
materials, and all comments received after the closing date, will also 
be filed and will be considered to the extent possible. When the 
petition is granted or denied, the notice will be published in the 
Federal Register pursuant to the authority indicated below.
    Comment closing date: August 29, 1994.

(49 U.S.C. 30118, 30120; delegations of authority at 49 CFR 1.50 and 
49 CFR 501.8)

    Issued on: July 25, 1994.
Barry Felrice,
Associate Administrator for Rulemaking.
[FR Doc. 94-18517 Filed 7-28-94; 8:45 am]
BILLING CODE 4910-59-M