[Federal Register Volume 64, Number 102 (Thursday, May 27, 1999)]
[Notices]
[Pages 28864-28866]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-13536]
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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
[Docket No. NHTSA-98-4008; Notice 2]
Grant of Application for A Decision of Inconsequential
Noncompliance With Federal Motor Vehicle Safety Standard 108--Lamps,
Reflective Devices and Associated Equipment
General Motors Corporation (GM) determined that certain 1998 GMC
Sonoma pickup trucks, GMC Jimmy and Oldsmobile Bravada sport utility
vehicles are equipped with daytime running lights (DRLs) that fail to
meet the spacing requirements of Federal Motor Vehicle Safety Standard
(FMVSS) No. 108--Lamps, Reflective Devices and Associated Equipment.
Pursuant to 49 U.S.C. 30118 and 30120, GM applied to the National
Highway Traffic Safety Administration (NHTSA) for a decision that the
noncompliance is inconsequential to motor vehicle safety. GM submitted
a 49 CFR Part 573 noncompliance notification to the agency in
accordance with 49 CFR 556.4(b)(6).
A notice of receipt of application was published in the Federal
Register (63 FR 40781) on July 20, 1998. Opportunity was afforded for
comments until September 21, 1998. One comment was received, from JCW
Consulting (JCW). The comment opposed granting the petition.
GM stated that DRLs on the subject vehicles utilize the upper beam
headlamps operating at reduced intensity, with a maximum intensity of
approximately 6,700 candela per lamp. FMVSS No. 108 requires these DRLs
to be located so that the distance from their lighted edge to the
optical center of the nearest turn signal lamp is not less than 100 mm,
with four exceptions that do not apply to these GM vehicles. However,
one of the exceptions permitted vehicles manufactured before October 1,
1995 that used an upper beam headlamp as a DRL to have a spacing of
less than 100 mm from the turn signal lamp if the turn signal were
sufficiently bright that it could have been spaced less than 100 mm
from a lower beam headlamp.
GM stated that 122,455 vehicles involved provide less than 100 mm
clearance between the DRL and the turn signal and that as a result,
they fail to meet FMVSS No. 108 requirements. GM believes that this
noncompliance is inconsequential to motor vehicle safety for the
following reasons:
1. The subject vehicles meet the requirements of CMVSS No. 108 (the
[[Page 28865]]
Canadian requirement) and the DRL requirements in FMVSS No. 108 for
vehicles manufactured before October 1, 1995.
2. CMVSS No. 108 requires turn signals that are located less than
100 mm from a DRL to have increased intensities of 2\1/2\ times the
minimum photometric values to help assure that the turn signals are
readily visible. The subject vehicles have turn signals that are much
brighter. When photometered, the subject turn signals were more than
four times brighter than the minimum required intensities. This
increased brightness helps in preventing turn signal masking by the
DRL.
3. The method for determining the optical center of the turn signal
is open to some interpretation. Traditionally, automobile manufacturers
have used the filament axes as the determining factor. Transport Canada
has supported this methodology. More recently some manufacturers have
used the centroid of the lamp as the optical center. Depending on the
method used, the turn signal of the subject vehicles is either 71mm
(using the centroid) or 85 mm (using the filament axes) away from the
DRL. Therefore the subject condition is within 15%, or using the more
conservative figure, within 30% of the requirement. (Note: GM used the
centroid method in this petition.)
4. Regardless of whether the distance is within 15% or 30% of the
100 mm requirement, the turn signal and the DRL are diagonal to each
other. Therefore the closest lighted edge of the DRL is the corner of
the lamp. (Note: Sketches submitted by GM are found in the petition
which is filed in the docket). This portion of the lamp does not
significantly contribute to the DRL beam pattern, and therefore does
not have a significant potential to mask the turn signal.
5. Photometric values of the turn signal 71 mm from the subject DRL
are not significantly different than a turn signal 100 mm from the
subject DRL. To demonstrate this, on-vehicle evaluations of the turn
signal output were made using a video-based photometer (digital CCD
camera system). First, the photometric output of the turn signal was
measured with the subject DRL activated. Then a portion of the DRL was
blocked (to simulate the necessary spacing) at the corner nearest the
turn signal (Note: a sketch illustrating this was included in the GM
petition and is available in the public docket). The output of the turn
signal was re-measured with the modified DRL activated. The zonal
values of the turn signal changed an average of just 12.7%. The largest
difference in turn signal output was found in zone 5, closest to the
DRL and it only changed 17.5%.
6. Subjective evaluations were run using GM personnel whose jobs do
not involve vehicle lighting. They were asked to rate the relative
visibility of turn signals on the subject vehicles and other vehicles
that meet the FMVSS No. 108 spacing requirement. The results shown in
the bar graph in Figure 3 of the petition (which can be found in the
docket) indicate that the visibility of the subject turn signals is
substantially better than vehicles that just meet the minimum
requirement. In addition the subject turn signals are rated nearly
identical to vehicles modified to be fully compliant to the
requirements, and rated only slightly lower than turn signals on the
Chevrolet Blazer (which is a similar vehicle whose turn signal/DRL
spacing meets the requirements of FMVSS No. 108).
7. The turn signals on the subject vehicles are 116 sq. cm., larger
than typical turn signals found on similar vehicles. FMVSS No. 108
requires the functional lighted area of a front turn signal lamp on
these vehicles to be a minimum of 22 sq. cm. Therefore, the subject
turn signals provide 5.3 times the minimum area to meet the
requirement. The larger size of the turn signal helps to minimize any
potential for masking by the DRL.
GM believes that the subject noncompliance is inconsequential to
motor vehicle safety, and petitioned that it be exempted from the
notification and remedy provisions of the Safety Act for this specific
noncompliance with FMVSS No. 108.
JCW Consulting (JCW), the lone commenter, opposed the grant of the
petition. JCW stated that these vehicles use the DRL design with the
``most objectionable'' levels of glare (low voltage upper beam
headlamps). JCW asserted that critical turn signal or hazard warning
flasher recognition could be masked by these DRLs if the oncoming
driver is very glare-sensitive. However, JCW presented no data to
substantiate its opinion that turn signal masking will be a problem on
these vehicles.
NHTSA has been sensitive to the need to prevent DRLs from masking
turn signals. The agency conducted research specifically designed to
investigate possible turn signal masking by DRLs (DOT HS 808 221,
Daytime Running Lights and Turn Signal Masking). The agency used older
drivers to represent the drivers most likely to be susceptible to turn
signal masking by DRLs. One of the findings of this research was that
it is possible to reduce turn signal masking by increasing turn signal
intensity regardless of separation distance. Equivalent detection was
found for turn signals separated from DRLs by only 50 mm with that of
turn signals separated from DRLs by 100 mm, if the intensity of the 50
mm turn signal was increased to three times that of the 100 mm turn
signal. Side-by-side and above-and-below headlamp and turn signal
configurations were studied. For both configurations, larger headlamps
and turn signals result in less masking than smaller headlamps and turn
signals.
In this case, the vertical and horizontal dimensions of the turn
signals on these GM vehicles are larger than most and provide 5.3 times
the minimum required area. In addition, GM has measured the turn
signals and found them to be four times brighter than the minimum
required intensity. This is significant because NHTSA's research showed
high turn signal intensity to be very important in preventing masking.
GM's subjective evaluation tests also confirmed the effectiveness of
higher turn signal intensity in preventing masking. Based on the
evidence presented by GM, the agency does not deem this specific
noncompliance on these vehicles to have a consequential effect on
safety .
NHTSA wants to make clear that the issue in this proceeding is the
adverse safety consequences from possible turn signal masking by this
particular DRL-turn signal combination, not the glare levels from upper
beam headlamp DRLs. NHTSA has an open rulemaking proposal to
substantially reduce glare from DRLs. The notice of proposed rulemaking
was published on August 7, 1998 (63 FR 42348). The agency will address
the concerns expressed in JCW's comment about the high intensity and
the high mounting height of the GM DRLs in that rulemaking.
In addition, NHTSA would like to provide some information in
response to the statement in GM's petition regarding uncertainty as to
how one determines the optical center of a turn signal. There should be
no such uncertainty. The agency has answered a letter specifically
asking whether the optical center of the turn signal lamp is the same
as the filament position when measuring the spacing relationship
between a turn signal lamp and a DRL (Caire, March 14, 1996). NHTSA's
interpretation explains:
``To determine the optical center of the turn signal lamp, we must
refer for an answer to SAE J588 NOV84, Turn Signal Lamps For Use on
Motor Vehicles Less than 2032MM in Overall Width. The answer depends on
the design of the turn signal lamp. If the lamp primarily employs a
reflector (for
[[Page 28866]]
example, one of parabolic section) in conjunction with a lens, spacing
is measured from the geometric centroid of the front turn signal
function lighted area to the lighted edge of the lower beam headlamp
(paragraph 5.1.5.4.2, SAE J588 NOV84). The ``geometric centroid'' is
the ``optical center'' for purposes of Standard No. 108. If the front
turn signal is a direct light source type design, that is a lamp that
is primarily employing a lens and not a reflector to meet photometric
requirements, spacing is measured from the light source to the lighted
edge of the DRL. The filament center of the light source is the
``optical center'' for purposes of Standard No. 108. If the distance is
less than 100 mm, the requirements of S5.3.1.7 apply and the minimum
intensity of the turn signal must be at least 2.5 times that normally
required.''
In consideration of the foregoing, NHTSA has decided that the
applicant has met its burden of persuasion that the noncompliance
described above is inconsequential to motor vehicle safety.
Accordingly, its application is granted, and the applicant is exempted
from providing the notification of the noncompliance required by 49
U.S.C. 30118, and remedy, required by 49 CFR 30120.
Authority: 49 U.S.C. 30118 and 30120; delegations of authority
at 49 CFR 1.50 and 501.8.
Issued on: May 24, 1999.
L. Robert Shelton,
Associate Administrator for Safety Performance Standards.
[FR Doc. 99-13536 Filed 5-26-99; 8:45 am]
BILLING CODE 4910-59-P
