[Federal Register Volume 61, Number 241 (Friday, December 13, 1996)]
[Proposed Rules]
[Pages 65510-65518]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-31747]


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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

RIN AG-38
[Docket No. 96-41, Notice 01]


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

AGENCY: National Highway Traffic Safety Administration (NHTSA), 
Department of Transportation.

ACTION: Notice of request for comments.

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SUMMARY: This document seeks public comment on the value of several 
signal lamp ideas which have been suggested to the agency, and on 
whether NHTSA should permit auxiliary signal lamps in addition to those 
required by Federal Motor Vehicle Safety Standard No. 108. NHTSA also 
seeks comment on a policy for the disposition of petitions for 
rulemaking that request the agency to require or permit safety lighting 
inventions and which are submitted without proof of their 
effectiveness.

DATES: Comments are due March 13, 1997.

ADDRESSES: Comments should refer to Docket No. 96-41, Notice 1, and be 
submitted to: Docket Section, room 5109, 400 Seventh Street S. W., 
Washington, DC 20590 (Docket hours are from 9:30 a.m. to 4 p.m.) It is 
requested that 10 copies of the comments be provided.

FOR FURTHER INFORMATION CONTACT:

For technical issues: Richard Van Iderstine, Office of Crash Avoidance 
Standards, NPS-21, telephone (202) 366-5280, FAX (202) 366-4329.
For legal issues: Taylor Vinson, Office of Chief Counsel, NCC- 20, 
(202) 366-5263, FAX (202) 366-3820.

    Both may be reached at the National Highway Traffic Safety 
Administration, 400 Seventh St., S.W., Washington, D.C., 20590. 
Comments should not be sent or FAXed to these persons, but should be 
sent to the Docket Section.

SUPPLEMENTARY INFORMATION

Background

    Federal Motor Vehicle Safety Standard No. 108 (``Standard No. 
108''), Lamps, Reflective Devices and Associated Equipment (49 CFR 
571.108) includes requirements for specified types of signal lamps to 
be installed on new motor vehicles, and regulates their performance in 
terms of color, brightness, quantity, duty cycle (steady or flashing) 
and details of activation (e.g., turned on with the headlamps). The 
purpose of these specifications is to establish the presence of a 
vehicle in the roadway, and to signal its driver's intentions to other 
motorists and pedestrians. Communication via these signal lamps is best 
accomplished with a degree of standardization in order to minimize 
ambiguity. In drafting the signal lamp requirements, NHTSA has balanced 
the need for standardization with its desire to allow as much design 
freedom as possible for the location, shape, styling, and light source 
design of the lamps. For example, the intensity ranges of taillamps and 
stop lamps are regulated so that a person can distinguish a red stop 
lamp from a red taillamp immediately at the initiation of braking, 
without having to notice the transition. However, the size and shape of 
stop lamps and taillamps are left to the designer of the device. 
Likewise, stop lamps are required to be steady-burning to distinguish 
them from the required flashing of turn signals and hazard warning 
signal lamps of the same brightness and color. Paragraph S5.1.3 of 
Standard No. 108 also allows for auxiliary lighting equipment beyond 
the required equipment, provided that the auxiliary equipment does not 
``impair the effectiveness'' of the required lamps and reflectors. (In 
the case of auxiliary lamps of emergency vehicles and tow trucks, the 
usual agency policy is to leave the specifications to the discretion of 
State governments.)
    Standard No. 108 is more flexible than the lighting regulations of 
most

[[Page 65511]]

other countries and many of the States. For example, while many 
countries require lamps to be located within specific dimensions, such 
as ``not more than 3 inches from the edge of the vehicle'', Standard 
No. 108 generally allows a manufacturer to locate lamps at such maximum 
heights and widths as the manufacturer determines are ``practicable.'' 
Also, many States prohibit auxiliary lamps unless expressly permitted 
by their lighting codes, even if they are permitted as optional 
equipment under Standard No. 108 because they do not ``impair the 
effectiveness'' of the lighting equipment required by the Federal 
standard.
    The agency is publishing this notice to obtain comment on four 
signal lighting ideas which their proponents believe will improve 
communication between drivers. The ideas are:
    (1) The activation of stop lamps upon sudden release of the 
accelerator pedal,
    (2) The flashing of center high mounted stop lamps (CHMSLs) at one 
or more rates to indicate heavy braking (or Anti-lock Braking System 
activation),
    (3) The flashing of one or more stop lamps to indicate a stopped 
vehicle, and
    (4) Stop lamps on the front of vehicles.
    NHTSA is also seeking comments to aid in developing a general 
policy that would maximize its consideration of potential safety 
advances and suggestions by inventors while enabling it to carefully 
screen new ideas to ensure that the public is not burdened with 
unjustified cost or annoyance, or subjected to hazards. Despite the 
relative degree of flexibility of Standard No. 108, inventors who have 
developed new signal lamps or new ways of using existing lamps 
nevertheless often find that their devices are in conflict with 
Standard No. 108 and State regulations. In addition, inventors commonly 
expect that NHTSA ought to require their inventions to be installed on 
new motor vehicles. At the same time, these requests are often 
accompanied by only very limited substantiation of the potential safety 
benefits. Adoption of some requests would not only increase the cost of 
new motor vehicles, but also in some cases reduce instead of increase 
safety.

Idea No. 1: Stop Lamps Activated by Rapid Release of the 
Accelerator Pedal

    In a situation on the road when hard braking is required to avoid 
an accident, it is an intuitively attractive idea to light the stop 
lamps sooner than in normal braking. However, this is not permitted by 
Standard No. 108, which requires that stop lamps be activated only upon 
application of the service brakes (paragraph S5.5.4).
    In 1994, Baran Advanced Technology Ltd. petitioned the agency to 
permit activation of the stop lamps using its Advanced Brake Warning 
System (ABWS). This system is designed to activate the stop lamps if 
the accelerator pedal is lifted at a rate greater than 0.3 meter a 
second, simulating the response of a driver in panic braking. Baran 
claimed that this lights the stop lamps 0.25 second sooner and could 
prevent a significant portion of rear end collisions. In support of its 
petition, Baran presented a study of the stop lamp activations of a 
small fleet of vehicles equipped with ABWS, operated over a period of 
several months by drivers unaware of the ABWS equipment. In about one-
fourth of the instances in which the ABWS activated the stop lamps, the 
driver did not touch the brake pedal, creating a ``false alarm'' 
lasting one second. However, the study also recorded a large number of 
instances in which there were brake applications that lasted one second 
or less. Baran concluded that the false alarms would increase, by only 
a few percentage points, the total number of short stop lamp 
indications and would not be noticeable as false alarms to the driving 
public. It argued that the agency should not, therefore, be concerned 
that the false alarms would dilute the effectiveness of the stop lamps 
and cause motorists to begin to discount the significance of stop lamp 
activation.
    NHTSA was concerned that ABWS might decrease the public's 
responsiveness to the message sent by the stop lamps. Today's stop 
lamps, which are activated only by the service brake system, send an 
unambiguous message to following drivers that the driver ahead is using 
the brakes. The precise purpose of the brake application (panic stop, 
ordinary stop, deceleration, disengagement of cruise control) requires 
the following driver to be aware of the traffic environment ahead. 
NHTSA believes that to the extent that the public would come to 
associate stop lamp activation with movements of the accelerator pedal 
rather than movements of the brake pedal, a dilution in the meaning of 
the present signal will occur. The petitioner showed that ordinary 
short brake applications would vastly outnumber ABWS false alarms and 
argued that the public would not be sensitive to false alarms. However, 
it is also possible that if the public were aware of the operation of 
the ABWS, it would incorrectly attribute many of the short brake 
applications to ABWS false alarms, creating an inappropriately high 
level of skepticism of stop lamp signals. Also, the fact that drivers 
experienced a large number of short inconsequential brake applications 
makes it less likely that they would use to advantage an earlier 
warning of only a fraction of a second, given the fact that so few 
brake applications actually resulted in a rapid deceleration.
    A related concern is the potential abuse of ABWS to create 
intentional false alarms. An increasing level of aggression and lack of 
courtesy on the part of drivers is now being reported. The safest way 
to deal with tailgating drivers on multilane highways is to pull over 
and allow them to pass. However, some drivers choose to return 
discourtesy by tapping the brake pedal to startle the tailgater. It is 
possible that the ease of lighting the stop lamps using the ABWS alone 
would tempt more drivers to contribute to traffic aggression, and that 
such behavior would dilute the message of stop lamp signals if a 
tailgating driver suspected that the vehicle ahead was equipped with 
ABWS.
    There is the possibility of some small benefit of ABWS in the 
following situation. Assuming that two vehicles are moving one behind 
the other at the same speed and that the lead driver brakes extremely 
hard and the trailing driver brakes equally hard at the first glimmer 
of the lead vehicle's stop light, some collisions could be prevented 
between vehicles with ordinarily insufficient headway provided that the 
driver of the trailing vehicle brakes 0.25 second sooner than (s)he 
would in response to current lighting systems. The benefits reported in 
Baran's analysis under these assumptions were greatest for braking at 1 
g under ideal pavement conditions because the assumed 0.25 second 
advantage does not result in much speed reduction when the pavement is 
slippery. It is not clear that these assumptions are realistic.
    Baran cited studies reporting that over 20 percent of drivers 
observed on a Michigan urban interstate highway maintained less than 1 
second headway and that 4 to 5 percent maintained a headway of less 
than half a second, supporting its point about the headway assumed to 
demonstrate the effectiveness of its ABWS. However, NHTSA questions the 
assumption that the trailing driver would react instinctively by 
braking extremely hard at the instant (s)he perceived a stop lamp 
illuminated by ABWS. If that driver knew the vehicle was equipped with 
ABWS and that false alarms do occur, (s)he might not react 
instinctively. At that instant, the lead car has not yet begun to 
brake, and there

[[Page 65512]]

is no speed differential between the two vehicles. Until tire squeal or 
extreme pitching motion of the lead car occurs, a trailing driver has 
no reason to slam on his or her brakes. The trailing driver in this 
analysis is a tailgater. It is possible that a tailgater who believes 
that ABWS false alarms are a regular occurrence will be even less 
likely to assume that hard braking is the required response upon 
suddenly seeing a stop light. In short, it is easy to foresee a 
situation in which the driver of a car being tailgated activates the 
stop lamps by ABWS several times without braking and then is confronted 
with an immediate need to brake fast, and the stop signal is initially 
ignored by the driver of the tailgating car.
    However, the typical rear-end crash does not involve a tailgating 
pair of vehicles with drivers attentive enough to respond to a minutely 
advanced stop signal. The agency's report Assessment of IVHS 
Countermeasures for Collision Avoidance: Rear-End Crashes, DOT HS 807 
995 May 1993, characterizes a rear-end crash as largely a dry/straight 
road phenomenon associated with driver inattention. In three-fourths of 
the rear-end crashes studied, the lead vehicle had been stopped, 
usually for 2 to 6 seconds before it was struck. There was adequate 
time to provide the following driver a warning with conventional stop 
lamps and for the following driver to avoid the crash. Of the other 
one-fourth of rear-end crashes, two-thirds did not involve following 
too closely. And most of the crashes attributed to following too 
closely also involved inattention on the part of the following driver.
    The assumption that even an attentive driver receives a 0.25 second 
sooner warning of panic braking of the car ahead may be optimistic. A 
report by the Technical University of Darmstadt in Germany, titled 
Efficiency of Advanced Brake Light Devices, FO57 May 1994, found that 
responses by attentive test subjects improved as a result of ABWS by 
only 0.10 to 0.15 second rather than by 0.25 second. The experiment 
simulated a convoy of three closely spaced vehicles. The center vehicle 
operated with and without ABWS. The time between the activation of the 
stop lamp of the lead vehicle and the braking response of the driver of 
the third vehicle was measured. With the vehicles stationary, the third 
driver responded 0.15 second sooner when the second vehicle used ABWS 
to active its stop lamps. This was approximately the same time taken by 
the driver of the second vehicle to move his foot from the accelerator 
to the brake pedal. When the experiment was replicated with the convoy 
traveling on public roads, the advantage provided by the ABWS 
diminished to 0.10 second as a result of the demands of the driving 
task on even an attentive test driver.
    The Darmstadt report also includes a study of the effect of a CHMSL 
on the lead car of the same convoy. Cars in Germany are not yet 
equipped with center high mounted stop lamps (CHMSLs). Under the same 
conditions in which the ABWS produced a response 0.10 second earlier by 
the third driver, the CHMSL produced a 0.45 second earlier response. 
The CHMSL enabled the driver of the third car to respond to the lead 
car before seeing the stop lamps of the second car. A similar effect 
occurred in night tests without the CHMSL because the third driver was 
able to see reflections of the lead car's stop lamps in the windshield 
of the second car.
    The most compelling argument for benefits is the implication that, 
if there are a large number of tailgating rear-end accidents, some of 
them must contain circumstances in which viewing a stop lamp 0.15 to 
0.25 second earlier would make a positive difference. Even if following 
drivers would not be willing to brake at the sight of a lamp (and many 
may be too inattentive to notice it immediately), it could be argued 
that the lamp may at least raise the state of expectancy of some 
following drivers sooner.
    In 1994, the agency denied Baran's petition to allow ABWS (59 FR 
39522). In the agency's opinion, the perception among drivers that ABWS 
allowed systematic and intentional false alarms would dilute the 
unambiguous message of conventional stop lamps. NHTSA concluded that 
the potential safety benefits of ABWS were not significant enough to 
outweigh its potential disadvantages. However, the notice of denial 
stated that NHTSA would consider the results of a fleet test of 
effectiveness of ABWS being conducted in Israel at that time. The 
objective of the Israeli study was to determine whether ABWS, already 
permitted in Israel, should be made mandatory. Germany also permits 
ABWS.
    In 1995, Baran and its United States partner, Allied Signal, Inc., 
submitted another petition for an amendment to Standard No. 108 to 
permit the optional use of ABWS. The petition bases its principal 
argument on NHTSA's statement in the 1994 denial that ``a manufacturer 
should not be precluded from offering its product, even if safety 
benefits cannot be demonstrated, unless there are potential safety 
disbenefits created by the product.'' The petition maintains that the 
agency's concern that stop lamp signals would become more ambiguous to 
the driving public is unfounded. Also, it disagrees that ABWS would be 
abused to create intentionally false braking or stop signals. It also 
reported that preliminary results from the ongoing Israeli fleet test 
showed that vehicles equipped with ABWS had been involved in fewer 
relevant collisions than ordinary vehicles, but that the numbers of 
comparative accidents were too few to establish statistical 
significance. The agency has granted that petition.
    The disagreement between the agency and Baran rests to a large 
degree on differences in assumptions of how ABWS would be used and 
perceived by drivers in the United States. Thus, the agency is 
particularly interested in comments from the driver's point of view, 
whether the individual drives for pleasure or is a professional driver 
of a commercial vehicle. The agency is interested in the views of 
researchers as well. If commenters know of relevant research data, they 
should provide the data.
    The questions which NHTSA asks commenters to address are:
    (1) How likely is it that an ABWS-type system would be abused to 
create intentionally false braking signals? What is the likely 
consequence of a false braking signal in a tailgating situation?
    (2) To what extent would the knowledge that stop lamps could be 
activated by rapid accelerator release change drivers' perceptions of 
the meaning of the stop lamp message?
    (3) If the answer to either question 1) or 2) is yes, would there 
be any changes in driver behavior, and if so, what would these changes 
likely be?
    (4) Should NHTSA propose to amend Standard No. 108 to permit an 
advance stop lamp warning system such as ABWS at the manufacturer's 
option or should the agency retain the present requirement that 
automobile stop lamps may only be activated by the purposeful 
application of the brake pedal by the driver? Would drivers buy such a 
system as an option, and if so, why?
    (5) Should NHTSA propose to amend Standard No. 108 to require an 
advance stop lamp warning system such as ABWS on new vehicles or should 
the agency retain the present requirement that automobile stop lamps 
may only be activated by the purposeful application of the brake pedal 
by the driver?
    (6) If an advance stop lamp warning system such as ABWS were 
configured to activate the CHMSL but not the other required stop lamps, 
would this reduce its potential for abuse to create intentionally false 
braking signals? How would this modification affect the intended 
purpose of a system such as

[[Page 65513]]

ABWS? How would this modification affect the intended purpose of the 
CHMSL?
    (7) Should NHTSA propose amending Standard No. 108 to (a) permit or 
(b) require a system such as ABWS which would activate only CHMSLs and 
not the other stop lamps?
    (8) Are there other bases for concluding that a system such as 
ABWS, either optional or mandatory, would degrade safety? If so, what 
are those bases?

Idea No. 2: Flashing CHMSLs To Warn of Hard Braking

    Many inventors have urged the agency to require CHMSLs to flash as 
a signal of hard braking. The agency presumes that the inventors hold 
design patents on specific devices which trigger and regulate a 
flashing lamp because the general concept of a flashing stop lamp would 
seem to be too much an obvious idea to be patentable. In addition, the 
flashing CHMSL is an idea which has been disclosed in public literature 
for at least 15 years.
    In many instances, inventors who petition NHTSA seem to believe 
that they can create a market for their patented products if they could 
have them incorporated into the Federal motor vehicle safety standards. 
This is an unrealistic expectation. A ``Motor vehicle safety standard'' 
is defined by 49 U.S.C. 30102(a)(9) as ``a minimum standard for motor 
vehicle performance.'' Motor vehicle safety standards are required to 
be ``practicable, meet the need for motor vehicle safety, and be stated 
in objective terms.'' (49 U.S.C. 30111(a)). This means that Standard 
No. 108 must and does express its requirements in terms of performance 
rather than design, leaving the individual manufacturer free to choose 
the means most appropriate to that manufacturer for achieving the 
stipulated performance. For example, if Standard No. 108 were to 
require a flashing CHMSL for hard braking, it would specify the color, 
brightness, flash rate and trigger condition (deceleration rate, ABS 
activation or other appropriate condition), but the operating principle 
of the device would be left to the manufacturer and not expressed in 
Standard No. 108. Manufacturers would be free to devise ways of 
satisfying a flashing CHMSL standard without infringing on existing 
patents. No Federal motor vehicle safety standard requires the use of 
patented designs. Of course, a manufacturer may decide that buying the 
rights to use a patented device is the most advantageous way of 
complying with a Federal motor vehicle safety standard.
    The agency, has in fact, studied the possibility of flashing 
CHMSLs, as was reported in the report Field Test Evaluation of Rear 
Lighting Deceleration Signals, DOT HS-806-125 October 1981. Each of 600 
taxis in a test fleet was equipped with one of three types of a CHMSL. 
The fleet traveled a cumulative 40.7 million miles during the study. 
The steady-burning CHMSL (the type adopted in Standard No. 108) was 
compared with two types of flashing CHMSLs. One flashed at a rate of 
2.5 Hz whenever the brake pedal was depressed. The other flashed at 1.5 
Hz, 2.5 Hz, 4 Hz or 7 Hz to relate higher braking rates to faster CHMSL 
flash rates. The highest flash rate occurred for all braking at greater 
than 0.3 g. Some of the rear-end accidents experienced by the test 
fleet did not involve braking by the struck vehicle. The remaining 129 
accidents, in which stop lamp usage could be presumed, were placed into 
three categories: vehicle stopped in traffic, vehicle stopping slowly, 
and vehicle stopping quickly. Seventy-eight percent of the rear-end 
accidents involved vehicles stopped in traffic. The other twenty-two 
percent were divided about equally between the stopping-slowly and 
stopping-quickly categories.
    A CHMSL that flashes to warn of hard braking would be expected to 
manifest its potential benefit by reducing accidents in which the 
struck vehicle was stopping quickly. Of the 48 rear end crashes 
experienced by the test vehicles equipped with ordinary steady-burning 
CHMSLs, six occurred while the vehicles were stopping quickly. Of the 
54 rear-end crashes experienced by the test vehicles equipped with 
CHMSLs with a flash rate proportional to the deceleration rate, four 
occurred while the vehicles were stopping quickly. That fewer vehicles 
with the hard-braking warning were struck while stopping quickly is 
suggestive of the expected desirable result, but the difference between 
six and four rear-end accidents was not great enough to be 
statistically significant. In other words, the apparent reduction from 
six to four accidents (given the total number of accidents and test 
vehicles) was not great enough to outweigh the possibility that the 
reduction was due to chance rather than to the effectiveness of the 
warning.
    The remaining third of the test vehicles were equipped with CHMSLs 
which flashed at same rate for all brake applications, regardless of 
deceleration rate. Of the 55 rear-end crashes experienced by the test 
vehicles equipped with constant-rate flashing CHMSLs, four occurred 
while the vehicles were stopping quickly. The accident results were the 
same for vehicles equipped with flashing CHMSLs with or without a 
distinct signal for hard braking. This suggests that the flashing 
action rather than the hard-braking warning (i.e., the increasing flash 
rate) was the source of whatever benefits the enhanced CHMSLs could 
provide over the performance of the ordinary steady-burning CHMSL. 
However, this comparison also lacks statistical significance.
    Speculation about these comparisons, which lack statistical 
significance, leads to an inconsistency when one considers the crashes 
into vehicles stopping slowly. It is a reasonable theory that flashing 
signals could counteract to some degree the effect of inattention that 
is an important cause of rear-end crashes. Under that theory, it is 
logical that fewer rear-end crashes occurred during quick stopping with 
either of the two flashing-CHMSL fleets than with the steady-burning 
CHMSL fleet. It is also logical to assume that inattention is the 
prevalent causal factor for rear-end crashes into vehicles stopping 
slowly because even partially attentive drivers have an opportunity to 
avoid such collisions. However, the fewest crashes into vehicles 
stopping slowly occurred in the fleet having steady-burning CHMSLs. The 
differences between fleets in crashes into vehicles stopping slowly 
were also too small to be statistically significant, and thus it is not 
surprising that the trends in performance of various types of CHMSLs 
were inconsistent.
    While the study provided no evidence that CHMSLs with flashing 
deceleration signals would be more effective than steady-burning 
CHMSLs, it did not rule out the possibility of an effectiveness benefit 
too small for statistical significance within the scope of the study. 
However, the study did conclude that any possible effectiveness would 
be limited to a small proportion of rear-end crashes. It cited studies 
conducted before 1981 to demonstrate that the large proportion of rear-
end crashes into stopped vehicles was not limited to studies of taxi 
fleets, and the much more recent studies cited above support the 
general finding that about three-fourths of the struck vehicles are 
stopped. A flashing warning of hard braking also has the possible 
disadvantage of an inherent time delay for the driver to see enough 
cycles to decide that the lamp is indeed flashing, if that driver does 
not brake on the first sight of red.
    At the time of this study of possible CHMSL enhancements, the 
agency had become convinced of the effectiveness of the steady-burning 
CHMSL through previous studies with unambiguous

[[Page 65514]]

results. NHTSA decided that it would not be in the interest of safety 
to delay a requirement for the basic steady-burning CHMSL while 
pursuing variants that were proving insignificant. The resulting 
requirement for CHMSLs permitted only steady burning CHMSLs despite the 
contemporary study of flashing CHMSLs. The result is that inventors 
regard the prohibition of flashing CHMSLs as unfair to their ideas.
    Neither the research reports nor the CHMSL rulemaking notices 
discussed the possibility of optional variants to the steady-burning 
CHMSL that might enhance its message. A favorable cost effectiveness 
was established for the steady-burning CHMSL, but no additional 
benefits have been found for flashing as a warning of hard braking that 
would justify the additional cost of requiring CHMSLs to flash. It is 
self evident that simplicity and a minimum of ambiguity are essential 
elements of signaling. Accordingly, NHTSA did not consider it necessary 
to seek comment on the option of a flashing CHMSL for hard braking when 
it proposed the requirement for a steady-burning CHMSL. The preamble to 
the final rule adopting the CHMSL expressed the possibility of future 
enhancements of brake signaling but in the context of requirements 
justified by effectiveness rather than as options (48 FR 4823). The 
CHMSL enhancement study theorized that the basic CHMSL was effective 
because it was less likely than ordinary stop lamps to be confused with 
other rear signals. The coexistence of more than one type of CHMSL 
signal would seem to undermine the clarity gained by the required CHMSL 
in comparison with conventional stop lamps.
    NHTSA studied CHMSLs that flash to indicate deceleration through 
hard braking as a potential requirement for a CHMSL but was not able to 
prove added effectiveness over steady-burning CHMSLs. Further, the 
agency believes that the lack of ambiguity or complexity of the 
conventional CHMSL is partly responsible for its effectiveness.
    With respect to this issue, NHTSA asks that commenters address the 
following questions:
    (1) Should NHTSA (a) permit, or (b) require CHMSLs to flash to 
indicate deceleration rate?
    (2) If flashing CHMSL deceleration signals were allowed but 
installed on only a few vehicles, would drivers understand their 
meaning?
    (3) Would the coexistence of flashing and steady-burning CHMSLs on 
the road create ambiguity? If the answer is yes, would the ambiguity be 
such as to diminish the effectiveness of the present steady-burning 
CHMSL?
    (4) Are there better cues than flashing to signal deceleration, 
e.g., an increase in lamp size or intensity?

Idea No. 3: Use of Flashing CHMSLs To Identify a Stopped Vehicle

    Two general conclusions of the research reports cited above are 
that most vehicles struck in rear-end crashes are stationary when they 
are struck and that inattention on the part of the driver of the 
striking vehicle is the prevailing cause of the crashes. These 
conclusions suggest that an attention-getting signal denoting a stopped 
vehicle has the potential to affect the conditions commonly involved in 
rear-end crashes. The potential value of a stopped vehicle signal was 
pointed out in the 1981 report, Field Test Evaluation of Rear Lighting 
Deceleration Signals (DOT HS-806-125), and the more recent NHTSA study 
of rear end crashes appears to support its reasoning.
    At least two inventors have approached the agency with the idea 
that a flashing CHMSL of one or more compartments could also be used as 
a stopped-vehicle signal. The flashing lamp is intended to gain the 
attention of approaching drivers better than a steady-burning lamp and 
to present a signal distinct from the usual stop signal. One inventor 
suggested several other embellishments to the CHMSL that flashes to 
indicate a stopped vehicle. These included having the CHMSL 
automatically flash whenever the vehicle speed is less than 22 mph, 
regardless of braking; having the CHMSL automatically flash at a higher 
intensity if the brakes are applied with the vehicle traveling at less 
than 22 mph; having the CHMSL automatically flash at a still higher 
intensity coupled with a faster flash rate to denote hard braking; and 
having the CHMSL maintain the hard-braking signal for a duration of 
several minutes after a crash.
    Once again, the requirement of Standard No. 108 that stop lamp be 
steady-burning is an impediment to allowing a flashing CHMSL signal for 
stopped or slow-moving vehicles. Also, the requirement that the CHMSL 
be activated only upon application of the service brakes prohibits any 
type of activation without brake use. In its interpretations of 
Standard No. 108 (e..g., letter to Ferguson, July 30, 1993), the agency 
has also said that the Standard prohibits a flashing auxiliary lamp, 
which was not intended to replace the standard CHMSL, because it could 
draw attention away from the required lamps and confuse their meaning. 
The inventors have urged the agency to change Standard No. 108 to allow 
the optional use of their stopped-vehicle signal devices.
    The idea of an attention-getting signal for stopped vehicles is 
attractive because it is aimed at the large percentage of rear-end 
accidents involving the combined factors of driver inattention and the 
striking of a stopped vehicle. But it is far from certain that the idea 
is practical and would actually prevent accidents. The idea seems 
practical in light traffic on rural roads. A single vehicle with a 
flashing CHMSL should attract attention and convey to the vehicles 
behind that it has stopped, if their drivers understand the meaning of 
the flashing lamp. But picture the situation if most of the vehicles in 
a traffic jam on an urban interstate highway were equipped with a CHMSL 
that automatically flashed when they were stopped or moving slowly. At 
the very least, it would be extremely annoying to be confronted with 
the flashing lamps of hundreds of vehicles, and it is likely that a 
concentrated array of vehicles with flashing CHMSLs would make ordinary 
brake, turn or hazard warning signals much less noticeable.
    It is difficult to determine the effectiveness of a device which 
may have different consequences if used universally by all vehicles on 
the road rather than in a small test fleet that is dispersed among the 
general vehicle population. Even a small test fleet study (which may 
cost about $750,000) is beyond the means of most inventors, and a major 
undertaking for the agency as well. In the case of the steady burning 
CHMSL, there were no potential safety disadvantages to its widespread 
use, but the level of benefits measured in fleet tests compared with 
follow up studies of accidents involving production vehicles suggest a 
novelty effect. Fleet tests of the CHMSL before it was required 
recorded reductions in rear-end accidents of about 50 percent. A 
follow-up evaluation by the agency after the CHMSL had been required 
equipment for a few years reported a 17 percent effectiveness for only 
those crashes that were police-reported, and a study by the Insurance 
Institute for Highway Safety reported only a 3 to 7 percent 
effectiveness.
    The lower effectiveness can be attributed in part, to a smaller 
percentage of crashes being reported to police than are reported to 
researchers during a fleet study. It may also be that drivers have 
become accustomed to the CHMSL and no longer respond to it as quickly. 
NHTSA is now measuring its long-term effectiveness. However, the

[[Page 65515]]

CHMSL experience suggests that the results of fleet studies are no 
indication that the long term universal use of a safety device will 
achieve the same degree of beneficial results.
    The following hypothetical example illustrates issues concerning 
the stopped-vehicle signal. The inventor and the research are 
imaginary, as are the hypothetical decisions of the agency.
    Assume that an inventor makes a large investment in testing a fleet 
of vehicles with a flashing CHMSL stopped-vehicle signal and finds a 
reduction in accidents. He expects the agency to permit or possibly 
require his device. But the fleet study cannot address the issue of 
widespread use. The agency believes that the experiment demonstrates 
the potential of the signal, but does not address the annoyance factor 
and signal masking in urban stop-and-go traffic. The agency decides not 
to amend Standard No. 108 to permit the stopped-vehicle signal unless 
the stop-and- go traffic problems are effectively addressed based on 
its judgment that stop-and-go traffic problems would exist if the 
device were in widespread use. However, it does not invest public money 
in an attempt to show by special tests that the widespread use of the 
device would cause a problem in stop-and-go traffic. The inventor views 
the result as unjust because he believes that he has supplied 
supportive facts at great cost and has been thwarted by what he regards 
as opinion and conjecture on the part of the agency.
    Taking the hypothetical example further, assume that the inventor 
later devises a way of solving the disadvantages of the stopped-vehicle 
signal in congested traffic, perhaps using rear-facing radar to turn 
off the signal after the vehicle behind has stopped. However, the 
improved device is too expensive relative to its probable benefits to 
justify its adoption as required equipment for new vehicles. The agency 
would remain interested in the idea in the hope that future technology 
or other solutions to its disadvantages in congested traffic will 
eventually lead to a practical and cost effective mandatory stopped-
vehicle signal.
    Relative to the stopped-vehicle signal, NHTSA requests that 
commenters address the following questions:
    (1) Should NHTSA disregard the potential irritant and distraction 
of automatically flashing stopped-vehicle CHMSL signals to permit their 
optional use (a) on the basis of an intuitive expectation of benefits 
in some circumstances? (b) on the basis of a fleet test demonstration 
of benefits as discussed in the hypothetical example?
    (2) Should the hypothetical improved, but not cost-effective 
flashing CHMSL signal be permitted as optional equipment? Will drivers 
understand the meaning of a CHMSL flashing under these circumstances 
since it is not standard equipment?
    (3) In the hypothetical example, based on its judgement of the 
public interest, the agency declined to change a safety standard that 
conflicted with an inventor's desire to sell products. Also, the agency 
declined to perform costly research for the purpose of attempting to 
confirm its judgment that the device had undesirable side effects. The 
question is whether NHTSA should base decisions against the wishes of 
petitioners on its judgement alone when no test data are available. In 
short, should the agency spend public money on research solely in an 
attempt to generate data to test a judgment decision about a seemingly 
clear problem with a petitioner's invention?

Idea No. 4: Front ``Brake'' Lamp Systems

    In its least costly form, a front ``brake'' lamp would use the 
front turn signal filament as a steady burning light to denote braking 
(but be overriden to indicate a turn, in the same manner as a combined 
red rear turn signal and stop lamp can indicate braking until the turn 
signal is activated). Thus, the front braking signal would be a bright 
amber lamp. The implementation is less simple than it appears because 
it would require wiring changes to present vehicles to prevent the 
deactivation of front side marker lamps wired to operate when the turn 
signals are activated (well nigh universal though not required by 
Standard No. 108), and to prevent the activation of amber rear turn 
signals during use of the front turn signal filaments as a steady 
braking signal.
    In a more costly form, presented by some proponents, front 
``brake'' lamps would be an additional pair of lamps, mounted at the 
front corners of the vehicle, and wired to operate with the red rear 
stop lamps.
    Standard No. 108 does not expressly address front ``brake'' lamps. 
They would not be prohibited unless they interfered with the 
effectiveness of required front lighting equipment (paragraph S5.1.3). 
Unlike the other devices discussed, front ``brake'' lamps could be 
offered as optional equipment on new vehicles without further 
rulemaking. While the proponents of the other ideas are currently 
seeking amendments to permit optional use of their devices, the 
proponents of front ``brake'' lamps insist that they lamps be mandatory 
on new vehicles. Such a request in the form of a petition for 
rulemaking was recently denied (61 FR 10556).
    The argument in favor of front ``brake'' lamps is that, by 
identifying the braking actions of a driver (driver A) to the drivers 
in front of him, oncoming drivers can better determine when driver A is 
yielding the right of way to them and the driver immediately ahead and 
going the same direction as driver A can better determine when driver A 
is failing to stop when necessary. According to the proponents, in the 
latter case, a driver stopped in traffic, seeing in the rear view 
mirror an approaching vehicle without a front braking signal, would be 
expected to sound the horn and vacate the lane.
    The agency does not anticipate any benefit from the front ``brake'' 
lamp. Until every car in use is equipped with a front braking signal, a 
stopped driver seeing in the rear view mirror an approaching vehicle 
without the signal would not know with certainty what its absence meant 
and whether a collision was imminent. Even after full implementation, 
the agency does not expect any benefits. NHTSA believes that, while it 
could be wise in some circumstances for a stopped driver to sound the 
horn upon seeing a vehicle approaching from the rear without 
illuminated front ``brake'' lamps, taking evasive action is likely to 
lead to the higher risk of a side or head-on collision with another 
driver who has the right-of-way.
    The agency also believes that the signal's activation would cause a 
dangerous disregard for State right-of-way laws at intersections by 
oncoming drivers who misinterpret the front stop signal on vehicles 
that have the right-of-way. Proponents of front ``brake'' lamps claim 
that their use will ``confirm'' the validity of a flashing turn signal, 
and thus allow drivers to determine at a distance whether a vehicle is 
surrendering the right-of-way. However, the use of signals does not 
cause a vehicle with the right-of-way to surrender it. The signaling 
driver is free to change his or her intentions, or the signal may be 
accidental. Consider the following scenario. A driver at a stop sign 
sees an approaching vehicle with the right-of-way displaying a turn 
signal and a front ``brake'' signal. The driver concludes that the 
front ``brake'' signal confirms the intent to turn, and pulls into the 
intersection. The operator of the other car, however, does not turn and 
a collision results. Perhaps the operator was slowing to check the name 
of the

[[Page 65516]]

street sign, with the intention of turning at a different street, or 
perhaps the turn signal was accidental and the braking unrelated. The 
likely result of widespread use of front braking lamps is not an 
enhancement of safety but an increase in traffic accidents due to a 
greater number of failures to yield the right of way. The only vehicles 
with a possible use for braking information about approaching vehicles 
are emergency vehicles which are allowed the right-of-way over all 
other vehicles on emergency runs.
    NHTSA asks commenters to address the following questions about 
front ``brake'' lamp systems:
    (1) Should NHTSA expressly prohibit front ``brake'' lamp systems?
    (2) Should NHTSA take no action on the presumption that the public 
would not choose to have front ``brake'' lamps, even if they were 
offered?

NHTSA Policy Considerations About Vehicle Signal Lamps Suggested by 
the Public

    Inventors who ask NHTSA to mandate their signal lamps as new 
vehicle equipment are often disappointed to learn that their idea is, 
in fact, not even allowed even as optional equipment because of 
restrictions in Standard No. 108 that either explicitly or implicitly 
prohibit them. Many of these ideas appear to be new but have been 
discussed for years, yet they have not been adopted because they are 
not permissible under Standard No. 108. The agency is willing to remove 
unintended impediments to the use of optional signal lamps if these are 
called to its attention, but it believes that the restrictions are 
necessary for motor vehicle safety. It is important that the integrity 
of the required signal lamps be maintained, and that auxiliary signal 
lamps not detract attention from the messages that the required signal 
lamps are sending. A vehicle signaling system must be as simple and as 
unambiguous as possible to others who share the roadway if traffic is 
to proceed in a safe and orderly fashion. As noted earlier, in many 
other countries, all auxiliary exterior lamps are expressly forbidden 
unless there is a specific regulation allowing it.
    Reasonable people may differ with NHTSA's views on the importance 
of a standardized signaling system, and the agency's conclusion that 
their auxiliary signal lamp design impairs the effectiveness of 
lighting equipment required by Standard No. 108, not understanding why 
the effectiveness of the required lamps should be favored over their 
inventions.
    Virtually all ideas suggested to NHTSA as safety improvements in 
vehicle signaling are based upon the intuition of the inventor, without 
any field data to support such intuition. NHTSA's prohibitive 
conclusions may seem intuitive as well, but the agency's decisions are 
based upon the criticality of maintaining standardization of vehicle 
signaling systems, and it does not conduct research solely for the 
purpose of verifying its intuition.
    The value of standardization of signals is largely treated as 
axiomatic in vehicle safety literature. The agency's survey of 
literature, Analytic Assessment of Motor Vehicle Rear Signaling Systems 
(1969), contains a typical discussion:

    To be maximally distinctive, by definition, the pattern must be 
unique; if maximum accuracy and speed of interpretation are to be 
obtained, the pattern must be unambiguously informative. A variety 
of patterns, even if some or all are more or less distinctive, 
cannot be as effective as a single standard pattern. (p. 78)

    Inventors must accept the fact that, when it is a question of the 
effect on required signals by auxiliary signals, NHTSA, the arbiter of 
the nation's traffic safety, is the proper party to make this judgment. 
It must be recognized also that this judgment is difficult to make, and 
must be made conservatively. The influence of many signaling ideas on 
driving behavior and crash causation is sufficiently subtle and the 
role of signaling systems in crash prevention and causation is 
sufficiently intertwined with that of other vehicle, driver and 
environmental factors that it is difficult to isolate and assess the 
effects of those ideas. Even if there were large sums of money 
available to the agency for conducting demonstration projects, the 
merits of one system versus another at full implementation would 
usually be hard to establish. Given the safety need to minimize the 
ambiguity in communication between drivers and the difficulty in 
establishing the ultimate net affect of changes in the signaling 
systems, the agency must be very cautious in permitting any changes.
    Another aspect of the agency's exercise of its rulemaking authority 
is that EO 12866 requires that benefits exceed costs if that is not 
inconsistent with the statute under which a regulation is issued. As 
noted above, it is difficult to demonstrate the effectiveness of 
signaling devices intended to avoid collisions. NHTSA has used large 
scale fleet tests, at great expense, to demonstrate the effectiveness 
of such items as the CHMSL and conspicuity treatment which have become 
requirements of Standard No. 108. However, even fleet tests cannot 
answer questions about the consequences of the use of a device on all 
vehicles rather than on just a few. Even an inventor with a large test 
budget may have to defer to the judgment of NHTSA on an issue which may 
be unprovable.
    Assuming that a suggested safety improvement is deemed cost 
effective and the agency wished to issue a rule adopting it as a 
requirement, 49 U.S.C. 30102(a)(9) dictates that the rule be expressed 
in terms of performance rather than design. Further, as a matter of 
policy, the agency is careful in its establishment of Federal Motor 
Vehicle Safety Standards not to adopt requirements for which compliance 
is dependent upon a patent that is not freely made available to all 
interested parties. These factors make it very unlikely that a patent 
holder would benefit if the agency were to issue a rule based generally 
upon an idea that the holder has suggested to the agency. Inventors who 
petition NHTSA in the expectation that the agency will issue rules 
creating a monopolistic market for their patents or devices, should be 
aware of probable outcome of their petitions before approaching the 
agency. In short, the rarity of cost-effective practical signal 
lighting ideas, the formidable task of proving their effectiveness, the 
existence of issues requiring NHTSA judgment, and the non-design nature 
of Standard No. 108 make it unlikely that an inventor will ever profit 
from a signal lamp suggestion.
    Other issues are raised by petitions for rulemaking to amend 
Standard No. 108 to permit specific auxiliary signaling systems at the 
option of the vehicle manufacturer. One issue, as discussed above, is 
whether a signal without universal application will be meaningful to 
the motoring public or simply a source of confusion. NHTSA is also 
reluctant to allow an optional system to operate through an existing 
required lamp, (e.g., allowing a CHMSL to flash) because in the future 
the agency may wish to use the mode of operation of the optional system 
(e.g., flashing) for a cost-effective mandatory signal and find that 
public experience and familiarity with the existing use of that mode 
has the practical effect of precluding the use or at least making it 
more difficult to use that mode for another purpose. Above all, there 
is the importance that the agency ascribes to minimizing ambiguity 
through standardization, and the diminution of standardization that may 
result from the introduction of optional signaling systems.

[[Page 65517]]

    The agency notes that it is not necessary for an inventor or 
manufacturer to seek an amendment of Standard No. 108 in order to 
perform a fleet test of a new signaling system. If a vehicle 
manufacturer wishes to produce a test fleet of vehicles incorporating 
lighting systems that may be prohibited by Standard No. 108, under 49 
U.S.C. 30113(b)(3)(B)(ii) it may petition for a temporary exemption 
from compliance with Standard No. 108 on the basis that ``the exemption 
would make easier the development or field evaluation of a new motor 
vehicle safety feature providing a safety level at least equal to the 
safety level of the standard.'' Alternatively, if a fleet owner wishes 
to install the equipment on a fleet of vehicles in service, the owner 
may accomplish this modification in its own garage without violating 
Federal law. The prohibition of 49 U.S.C. 30122 against making 
inoperative safety equipment installed in compliance with a Federal 
motor vehicle safety standard applies to manufacturers, distributors, 
dealers, and motor vehicle repair businesses, but not to persons who 
modify their own vehicles in self-owned repair facilities.
    The agency wishes to continue to receive suggestions for safety 
improvements from any source, even though few are likely to result in 
the incorporation of new requirements in Standard No. 108. However, 
petitioners should not have unrealistic expectations. They should 
understand that a petition for rulemaking does not obligate the agency 
to perform research on the effectiveness of the idea suggested. The 
agency's research plans flow from an internal process of defining 
priorities, formulating research plans, seeking appropriations, 
allocating available funds among the priorities and awarding research 
contracts. The effect of NHTSA's receipt of a petition for rulemaking 
is to cause the agency to begin evaluating the probability of the 
suggestion becoming a new requirement in a safety standard. This 
evaluation is based on information provided by the petitioner and other 
information the agency may have or obtain. Since few petitioners offer 
little more than speculation or testimonials about the effectiveness of 
their ideas, their petitions are unlikely to alter the agency's 
research priorities. Thus, the petitions are usually denied unless they 
relate to an existing agency research project.
    Petitioners should also understand that the agency is statutorily 
required to publish a notice when it denies a petition. In that notice, 
the agency must explain the reasons for the denial, which may require a 
discussion on the possible disadvantages of the system for which 
rulemaking had been sought.
    The agency believes that, in the long run, it would be more 
productive, both for inventors and the agency, if suggestions were 
presented to NHTSA's Office of Research and Development as candidates 
for future agency research. If the suggestions have merit, they can 
influence agency priorities and be included in research with the 
possibility of rulemaking at the conclusion of the research project. A 
petitioner who instead submits a petition is, more likely than not, 
likely to be frustrated in its dealings with NHTSA. It is the agency's 
hope that by explaining in this notice the factors that go into its 
decisions on lighting safety ideas, the public will have a clearer 
understanding of those factors and be guided thereby.
    In summary, a petitioner seeking to persuade the agency to mandate 
a lighting invention for new vehicles bears the initial burden of 
establishing its safety value and cost effectiveness. The burden for 
those inventors seeking to make an invention optional is to convince 
the agency that the invention will not impair the effectiveness of 
required lighting equipment through creating ambiguity or negatively 
affecting standardization of signals.
    The questions relating to these topics for which NHTSA seeks 
answers from the public are:
    (1) (a) Should NHTSA permit all auxiliary signals, regardless of 
their nature, their effect on required signals (other than physical 
interference), or their effect on signal standardization?
    (b) Should the agency permit the required signals only? Should the 
agency continue to prohibit auxiliary signals which, in its judgment, 
diminish the value of required, standard signals?
    (2) If an auxiliary signal can be demonstrated to have some 
effectiveness, but not enough to support requiring it, should the 
agency attempt to balance this limited benefit against the desirability 
of standardized signals in determining whether to allow the auxiliary 
signal as optional equipment?
    (3) Should NHTSA establish a policy to treat all new signal 
petitions as suggestions for future agency research if they do not 
present scientific evidence of effectiveness?

Rulemaking Analyses and Notices

Executive Order 12866 and DOT Regulatory Policies and Procedures

    This rulemaking document was not reviewed under E.O. 12866, 
``Regulatory Planning and Review.'' NHTSA has analyzed the impact of 
this rulemaking action and determined that it is not ``significant'' 
under the Department of Transportation's regulatory policies and 
procedures. NHTSA does not anticipate that new requirements would be 
imposed on manufacturers as a result of this request for comments. The 
main topic of the document is whether the agency should permit four 
types of signal lamps which, except for front signal lamps, have been 
suggested as optional rather than mandatory equipment.

Procedures for Filing Comments

    Interested persons are invited to submit written comments, and 
answers to the questions posed above. Please submit comments in 10 
copies to reduce duplicating costs to the government .
    Comments must not exceed 15 pages in length (49 CFR 553.21). This 
limitation is intended to encourage commenters to detail their primary 
arguments in concise fashion. Necessary attachments, however, may be 
appended to those comments without regard to the 15-page limit.
    If a commenter wishes to submit certain information under a claim 
of confidentiality, three copies of the complete submission including 
the purportedly confidential business information should be submitted 
to the Chief Counsel, NHTSA at the street address shown above, and 
seven copies from which the purportedly confidential information has 
been expunged should be submitted to the Docket Section. A request for 
confidentiality should be accompanied by a cover letter setting forth 
the information specified in 49 CFR 512, the agency's confidential 
business information regulation.
    All comments received on or before the close of business on the 
comment closing date indicated above for the notice will be considered, 
and will be available to the public for examination in the docket at 
the above address both before and after the closing date. To the extent 
possible, comments received after the closing date will be considered 
by the agency in its decisions as to the issues raised in this notice. 
Comments on the notice will be available for public inspection in the 
docket. NHTSA will continue to file relevant information in the docket 
after the closing date, and it is recommended that interested persons 
continue to monitor the docket for new material.
    Those persons desiring to be notified upon receipt of their 
comments in the rules docket should enclose a self-addressed stamped 
postcard in the envelope with their comments. Upon receiving the 
comments the docket

[[Page 65518]]

supervisor will return the postcard by mail.

    Authority: 49 U.S.C. 322, 30111, 30115, 30117, and 30166; 
delegation of authority at 49 CFR 1.50 and 501.8.

    Issued on: December 10, 1996.
L. Robert Shelton,
Associate Administrator for Safety Performance Standards.
[FR Doc. 96-31747 Filed 12-10-96; 4:34 pm]
BILLING CODE 4910-59-P