receptor head(s) within the specified range on a candidate stimulus
vehicle, then that vehicle would not be eligible for use as a stimulus
vehicle. This photometer receptor head placement constraint effectively
acts as a constraint on vehicles that may be used as stimulus vehicles
and excludes vehicles that ride unusually high or low. We are proposing
this constraint because we recognize it may be difficult or impossible
to design a headlighting system accommodating such outlier vehicles.
The existing Table XIX lower beam photometry requirements are such that
low-to-the-ground vehicles may be subject to glare even by a compliant
lower beam. We would also constrain ourselves by not using unusually
high vehicles to ease potential testing burdens on manufacturers.
Summary
    We tentatively believe this broad range of stimulus vehicles is
reasonable to adequately ensure that an ADB system functions robustly
and avoids glaring other drivers; we are concerned about a test
procedure effectively permitting an ADB system designed to accommodate
only a narrow range of oncoming or preceding vehicles. The purpose of
the stimulus vehicle is to elicit headlamp beam adaptation by an ADB
system and test whether the ADB system recognizes oncoming and
preceding vehicles and appropriately limits the amount of light cast on
these vehicles to ensure that they are not glared. This requires an ADB
system be able to appropriately detect and identify light coming from
another vehicle and dynamically shade that vehicle. An ADB system must
be able to recognize multiple possible configurations of headlights and
taillights, on vehicles of different size and shape (within a
reasonable range).
    We tentatively believe it would be practicable for a manufacturer
to design an ADB system to recognize and shade any vehicle satisfying
the proposed selection criteria. Although we are proposing a relatively
broad range of eligible stimulus vehicles, the lighting configurations
an ADB system would have to recognize are not unbounded. Front and rear
lighting designs are limited by the requirements of FMVSS No. 108 and
realities of vehicle design. Mounting heights, number, color, and
locations of vehicle lighting are constrained by requirements set out
in Table I of FMVSS No. 108. For example, headlamps must be white and
mounted at the same height symmetrically about the vertical centerline,
as far apart as practicable, and mounted at a height of not less than
22 inches nor more than 54 inches. Additionally, while we are proposing
a broad array of makes and models as test vehicles, there is a limited,
and not exceptionally large, number of makes and models of vehicles
offered for sale in the United States every year. For example, in Model
Year 2017, approximately 420 makes/models of passenger cars, trucks,
vans, and SUVs were offered for sale. The set of vehicles eligible to
be used as test vehicles will be further limited by the height
constraint we are proposing.
    We seek comment on the proposed vehicle selection criteria. Do the
criteria define a set of stimulus vehicles that is so large as to be
impracticable or unnecessary? If so, in what specific ways would
manufacturers find them impracticable, or why are they unnecessary
(i.e., how could the Agency be confident that glare prevention could be
adequately ensured with a smaller set of possible stimulus vehicles)?
Are the alternative criteria mentioned above preferable, and if so,
why? Are there other vehicle selection criteria that would result in a
smaller set of eligible stimulus vehicles but that would still be
sufficient to adequately discriminate between a robust ADB system and a
less robust ADB system?
2. Alternative: Test Fixtures
    We also considered using test fixtures instead of vehicles for the
purpose of eliciting an ADB response as part of a compliance test. SAE
J3069 specifies stationary test fixtures (structures intended to
simulate the front or rear of an actual vehicle) in place of actual
vehicles. It specifies four test fixtures: An opposing car/truck
fixture; an opposing motorcycle fixture; a preceding car/truck fixture;
and a preceding motorcycle fixture. The fixtures are fitted with lamps
simulating headlamps and taillamps. For headlamp representations, it
specifies a lamp projecting 300 cd of white light in a specified manner
and angle. For the taillamp representations, it specifies lamps
emitting no more than 7 cd of red light in a specified manner and
angle. The fixtures are fitted with photometers positioned near where a
driver's eyes would be to measure the light from the ADB test
vehicle.\83\ The lamp and photometer locations are based on ``median
location values provided by [the University of Michigan Transportation
Research Institute].'' \84\ SAE specifies test fixtures to reduce test
variability and because it considers stationary fixtures as a ``worst
case since some camera systems utilize opposing or preceding vehicles
movement within a scene to identify them as vehicles instead of other
road objects, such as reflectors on the side of the road.'' \85\ There
was also a ``concern that if the actual lower beam headlamps were used
on the opposing vehicle test fixture the large gradients present in
typical lower beam patterns would cause unnecessary test variability.''
\86\
---------------------------------------------------------------------------

    \83\ SAE J3069 5.5.2 and Figures 1 and 2 (opposing vehicle
fixture); 5.5.3 and Figures 3 and 4 (preceding vehicle fixture).
    \84\ SAE J3069, p. 3.
    \85\ SAE J3069, p. 3.
    \86\ SAE J3069, p. 4.
---------------------------------------------------------------------------

    We are not proposing to use test fixtures because we have
tentatively concluded they may not be sufficient to ensure that an ADB
system operates satisfactorily in actual use. Using stationary test
fixtures as opposed to dynamic actual production vehicles has the
advantage of relative simplicity and ease of testing. However, the
drawback is that it is not realistic. Test fixtures may encourage an
ADB system designed to ensure identification of test fixtures rather
than actual vehicles. This may not adequately ensure that the system

performs satisfactorily when faced with a wide range of different
vehicles equipped with lighting differing from the test fixtures. In
addition, to the extent that test fixtures differ in appearance from
actual vehicles, an ADB system would have to be programmed to recognize
them, which in practice might make it difficult to tune out non-vehicle
objects confronting the system in actual use. Regarding gradients in
typical headlamp beam patterns, we tentatively believe this will only
affect the repeatability of the test if the reaction by the ADB system
changes based on this difference. If this is the case, the ADB system
will have this issue in actual use, and this should not be considered
variability attributable to the test, but a failing of the ADB system.
    We are also not necessarily confident that stationary fixtures with
lamps represented as specified in SAE J3069 represent a worst-case
scenario. Some ADB systems may have more difficulty detecting moving
dim lights or moving lights spaced a certain width apart. The Agency
welcomes any data relating to this. In addition, we seek comment on the
extent to which narrowly defined lamps can be used to establish
performance requirements that reasonably ensure an ADB system will
recognize and adapt appropriately to the wide range of lighting
configurations permitted under FMVSS No. 108. For instance, the minimum
intensity allowed for a taillamp is 2.0 cd at H-V and as low as 0.3 cd
at an angle of 20 degrees. These values are considerably lower than the
7.0 cd lamp specified in SAE J3069. Using stationary test fixtures
would likely reduce test variability. However, we tentatively believe
that the variability attributable to the proposed procedure would be
within acceptable limits considering the previously described necessity
of vehicle-level testing as demonstrated by NHTSA's research. As
discussed below in Section VIII.c, the variability the Agency observed
in the test results between a stationary lower beam and a moving test
vehicle lower beam (most applicable in the straight approach maneuver)
seemed to primarily be caused by the moving test vehicle not the moving
stimulus vehicle.
3. Photometer Placement
    The photometer measures the amount of light cast by the ADB test
vehicle falling on the stimulus vehicle. Our general approach is to
place the photometer \87\ near where the driver's eyes would be (to
measure glare to oncoming vehicles) or near where light would strike an
inside or outside rearview mirror (to measure glare to preceding
vehicles).
---------------------------------------------------------------------------

    \87\ Or, perhaps more accurately, photometric receptor heads,
if, for example, the photometer is configured with multiple receptor
heads, as was the case in NHTSA's testing. For ease of exposition,
the discussion in this document simply refers to the ``photometer''
to refer to the test equipment used to detect the light emitted from
the ADB system. In addition, we may use multiple photometers or
receptor heads simultaneously.
---------------------------------------------------------------------------

a. Oncoming Vehicles

    Here the approach is to measure light cast near where the driver's
eyes would be. Below we explain our proposal, as well as several
alternatives.
Proposal
    We propose to specify the position of photometers with respect to
the X, Y, and Z coordinates \88\ (i.e., the longitudinal, lateral, and
vertical placement of the photometers). With respect to the
longitudinal position, we propose to mount the photometer(s) outside
the vehicle, forward of the windshield and rearward of the headlamps.
Measuring headlight illuminance in front of the windshield is
consistent with the proposed glare limits; they are derived from the
current glare test points, which apply to light coming from a headlamp
and do not take into account effects related to the windshield glass.
If the photometer were placed behind the windshield, test results might
depend on properties of the windshield, which is undesirable because
the purpose of the test is to measure ADB system performance.
---------------------------------------------------------------------------

    \88\ See SAE J1100 FEB2001, Motor Vehicle Dimensions.
---------------------------------------------------------------------------

    With respect to the lateral and vertical positions of the
photometer(s), we are proposing specifying a range of permissible
positions.
    With respect to the lateral position of the photometer, we propose
locating the photometer anywhere from the longitudinal centerline of
the stimulus vehicle over to and including the driver's side A-pillar.
    With respect to the vertical position of the photometer, we propose
placing it anywhere from the bottom of the windshield to the top of the
windshield, subject to an upper bound and a lower bound. These upper
and lower bounds, which differ based on vehicle classification and
weight, are set out in the proposed regulatory text and are reproduced
in Table 4. If it is not possible to place a photometer on a candidate
measurement stimulus vehicle so the photometer was both between the top
and bottom of the windshield and within the applicable range in Table
4, then that vehicle would not be eligible for use as a stimulus
vehicle.

                                                     Table 4
----------------------------------------------------------------------------------------------------------------
                                                                                Height range (m)
                  Vehicle classification/weight                        Mean      -------------------------------
                                                                                Lower bound     Upper bound
----------------------------------------------------------------------------------------------------------------
Passenger Cars..................................................            1.11            1.07            1.15
Trucks, buses, MPVs (light).....................................            1.42            1.26            1.58
Trucks, buses, MPVs (heavy).....................................            2.33            1.99            2.67
Motorcycles.....................................................            1.43            1.30            1.66
----------------------------------------------------------------------------------------------------------------
``Light'' means vehicles with a GVWR of 10,000 lb. or less. ``Heavy'' means vehicles with a GVWR of more than
  10,000 lb. Heights are measured from the ground.

    The ranges for passenger cars and light trucks, buses, and MPVs are
from a 1996 University of Michigan Transportation Research Institute
(UMTRI) study estimating mean driver's eye heights based on a sample of
high-sales volume vehicles and drivers.\89\ The range for heavy trucks,
buses, and MPVs is from a 1990 study based on a sample of heavy goods
vehicles in a 1989 roadside survey in the United Kingdom.\90\ The
ranges we are proposing are the two standard deviation ranges.\91\
These are consistent with the photometer heights specified in SAE J3069
for the opposing vehicle fixtures. SAE J3069 specifies heights of 1.1 m
and 2.2 m for the photometers used to measure oncoming glare to drivers
of passenger cars and trucks, respectively. While SAE J3069 specifies a
point, not a range, the points it specifies for the passenger car and
truck driver eye heights are based on the same means we used to
construct the height ranges for passenger cars and heavy trucks/buses.
(SAE J3069 does not distinguish between heavy and light trucks, and
appears to use a mean for truck driver eye height that is a slight
downward adjustment of the heavy truck mean reported in the Cobb
study).
---------------------------------------------------------------------------

    \89\ Michael Sivak, et al. 1996. The Location of Headlamps and
Driver Eye Positions in Vehicles Sold in the U.S.A. UMTRI-96-36.
University of Michigan, Transportation Research Institute, p. 9.
    \90\ J. Cobb. 1990. Roadside Survey of Vehicle Lighting 1989.
Research Report 290, Department of Transport, Transport and Road
Research Laboratory (cited and discussed in Michael Sivak, et al.
1991. The Influence of Truck Driver Eye Position on the
Effectiveness of Retroreflective Traffic Signs. UMTRI-91-35.
University of Michigan, Transportation Research Institute, p. 8.).
    \91\ The American Association of State Highway and
Transportation Officials (AASHTO) uses similar values for driver's
eye height for measuring sight distances. A Policy on Geometric
Design of Highways and Streets. 2011. AASHTO (hereinafter ``AASHTO
Green Book''). It recommends 1.08 m for passenger vehicles and 2.33
m for large trucks (and notes a range of 1.8 to 2.4 m for large
trucks). Id. pp. 3-14. The AASHTO values are based on a 1997 study
by the Transportation Research Board, which estimated the values for
passenger cars, multipurpose vehicles, and heavy trucks. Daniel B.
Fambro, et al. 1997. NCHRP Report 400: Determination of Stopping
Sight Distances. Transportation Research Board, National Research
Council, National Cooperative Highway Research Program. The driver
eye height values used by AASHTO for passenger cars and large trucks
appear to be the 10th percentile values reported in the NCHRP report
for passenger cars and heavy trucks, respectively. NCHRP Report 400,
pp. 44-45 (Tables 31 and 33). The mean values in the NCHRP report
are 1.15 m (passenger cars), 2.45 m (large trucks), and 1.48 m
(MPVs). Since these estimates are based on a dynamic road survey
conducted (largely) in 1993, they are based on older vehicles than
the MY 1996 vehicles surveyed by UMTRI. The heights found by UMTRI
are lower than in the NCHRP report; this is consistent with the
observation that driver eye heights have tended to decrease over
time. See AASHTO Green Book, p. 3-14.
---------------------------------------------------------------------------

    The height range for motorcycles was determined as follows. The
opposing motorcycle test fixture specified in SAE J3069 locates the
photometer coincident with the rider's eye point, 1.3 m above the
ground. This appears to have been based on the 5th percentile
motorcycle rider eye height of 1.35 m reported in a study that examined
motorcycle rider eye heights in Malaysia.\92\ We propose this as the
lower bound for the vertical height of the photometer. For the upper
bound, we propose using 1.66 m, which is based on a two-standard
deviation range.\93\
---------------------------------------------------------------------------

    \92\ Seyed Davoodi et al. 2011. Motorcycle Characteristics for
Sight Distance Investigation on Exclusive Motorcycle Lanes. Journal
of Transportation Engineering, 137(7): 492-495.
    \93\ Specifically, this is based on the mean of 1.43 m reported
in Davoodi et al and the standard deviation reported in another
paper (.117 m). See Terry Smith, John Zellner & Nicholas Rogers.
2006. A Three Dimensional Analysis of Riding Posture on Three
Different Styles of Motorcycle. International Motorcycle Safety
Conference, March 2006. This paper compares the riding posture
(using anatomical landmarks) of a sample of human test subjects to
the posture of the Motorcycle Anthropometric Test Dummy (MATD). The
paper reports, among other things, the standard deviation of the
vertical location of the test subjects' left infraorbitale (a point
just below the eye) relative to the infraorbitale of the MATD of
.117 m. In other words, the study reports the standard deviation of
the vertical location of the infraorbitale relative to a fixed
point.
---------------------------------------------------------------------------

    We tentatively believe that the proposed specification for the
placement of the photometers meets the need for safety and is
practicable. It defines a bounded area approximating the location of
the driver's (or rider's) eyes. Unlike a specification for an eye
ellipse,\94\ which defines a smaller area more precisely targeting
where the driver's eyes would likely be located, the larger area we
specify provides a margin for safety and is easier to locate. Given
that ADB is currently designed to shade an entire approaching or
preceding vehicle, we believe focusing on a small area such as that of
an eye ellipse is not necessary. Instead, ``the expectation is that ADB
will reduce any glare producing light toward and on the full width of
opposing and preceding vehicles, thereby providing benefit to all
occupants in the vehicle.'' \95\ However, we propose to subject the
vertical placement of the photometer to a lower bound because we
recognize it may be difficult to design an ADB system to prevent
glaring extremely low-riding vehicles with correspondingly low driver
eye heights; we recognize that because of the low height, even an FMVSS
No. 108-compliant lower beam might glare such a low-riding driver. We
are proposing an upper bound on photometer placement to limit the
conceivable test locations; we also do not anticipate ADB systems would
produce high levels of illumination at heights above the ranges we are
proposing. At the same time, we believe a two-standard deviation range
captures enough variation to require the design of robust ADB systems.
We also believe specifying these bounds will ensure tests are not
unduly stringent. If a candidate stimulus vehicle is such that there is
no position between the top and bottom of the windshield that would be
within these bounds, then that vehicle would not be eligible for use as
a stimulus vehicle.
---------------------------------------------------------------------------

    \94\ SAE J941, Motor Vehicle Drivers' Eye Locations.
    \95\ SAE J3069, p. 3.
---------------------------------------------------------------------------

    We seek comment on the proposed specifications for photometer
placement. In particular, we seek comment on whether the proposed
height range is necessary, and if so, whether the proposed
specification is sound.
Alternatives to Proposal
    We also considered alternative procedures for determining the
lateral and/or vertical position of the photometer(s) to measure
oncoming glare. We discuss these below. Note that these are not
alternatives for determining the longitudinal position of the
photometer. In addition, for all of these alternatives, the vertical
position of the photometer(s) would be subject to the upper and lower
bounds proposed above.
Alternative 1
    We considered specifying the lateral and vertical position of the
photometer by using a test procedure based on that currently used to
locate the approximate eye position of a 50th percentile male in
compliance testing for the FMVSS No. 111 rear visibility field of view
and image size requirements. FMVSS No. 111 requires, among other
things, a visual display of an image of an area behind the vehicle and
specifies certain requirements for the image. The field of view and
image size test procedures locate where eyes of a typical driver would
be. More specifically, they locate the midpoint of the eyes of a 50th
percentile male. The test procedure specifies the eye midpoint by using
the H-point as a point of reference. The H-point is used in several
other NHTSA standards \96\ and represents a specific landmark near the
hip of a 50th percentile adult male positioned in a vehicle's driver
seat. It has been used by NHTSA as well as other organizations in

the context of visibility measurement. SAE J826 JUL95 defines and
specifies a procedure, including a manikin (``H-point manikin''), for
determining the exact location of the H-point in a vehicle; it
specifies the H-point in relation to the hip location of a driver in
the driver seating position. The rear visibility test procedure uses
the J826 manikin and procedure to locate the H point. It then uses
anthropometric data from a NHTSA-sponsored study of the dimensions of
50th percentile male drivers \97\ to locate the midpoint between the
driver's eyes.\98\ In practice, a testing laboratory typically uses an
H-point manikin fitted with a camera (which is needed for the field of
view and image size tests) positioned at the driver's eye midpoint.
---------------------------------------------------------------------------

    \96\ See, e.g., FMVSS No. 208, S10.1; FMVSS No. 210, S4.3.2.
    \97\ L.W. Schneider, D.H. Robbins, M.A. Pfliig, & R.G. Snyder.
1985. Anthropometry of Motor Vehicle Occupants; Volume 1-Procedures,
Summary Findings and Appendices. National Highway Traffic Safety
Administration, DOT 806 715.
    \98\ See generally 75 FR 76232.
---------------------------------------------------------------------------

    We considered a simplified version of this procedure to determine
the approximate vertical and lateral position (the Z and Y coordinates)
of the expected eye position of a 50th percentile male driver. The
driver's seat positioning test procedure in S<IP_ADDRESS> and part of the
test reference point procedure (S14.1.5(a)) in FMVSS No. 111 locates
the center of the forward-looking eye midpoint with respect to the H-
point. We considered using the Z and Y coordinates of the forward-
looking eye midpoint to specify the position of the photometer in front
of the windshield. This procedure would locate the photometer
approximately where the eyes of an average male driver would be.
Mounting the photometer at different but nearby locations (e.g., a
location corresponding to the forward-looking eye midpoint of a 5th
percentile female) would add additional testing burden while likely not
affecting the outcome of the test. This alternative test procedure
would appear to be practicable. The H-point machine is a fairly
standard piece of laboratory test equipment used in other FMVSS and SAE
standards. Compared to the proposed test procedure, there would likely
be some additional work involved in positioning the manikin, but this
may not add an exceptional amount of cost or time to the test,
particularly if the laboratory performing the test already had an H-
point machine. This alternative might be preferable to the proposed
option if it were determined ranges utilized by the proposed option did
not have a sound basis.
Alternative 2
    As another alternative for specifying the lateral and vertical
position of the photometer(s), we considered obtaining from the
manufacturer of the stimulus vehicle the coordinates of the midpoint of
the 50th percentile male's drivers' eyes. We believe most vehicle
manufacturers would have this information and could supply it to NHTSA.
The purpose of this would be to save the Agency time in doing the test,
perhaps if an H-point machine were not readily available. While there
would be some difference between the photometer location compared to
Alternative 1, we believe such relatively small changes would not
meaningfully affect test outcomes. If a manufacturer desired to conduct
testing following NHTSA's test procedures, it could use a stimulus
vehicle it manufactures, or, if it desired to use a stimulus vehicle
manufactured by another manufacturer, it could potentially obtain
information from the manufacturer of that vehicle.
Alternative 3
    We also considered, as an alternative for locating the photometer
with respect to the Z and Y axes, using SAE J941 JAN2008, Motor Vehicle
Divers' Eye Locations. This document describes a procedure for locating
a mid-centroid driver's eye ellipse. We tentatively concluded that, for
purposes of compliance testing, J491 would not provide an easy enough
to follow procedure; we believed that it would be easier to use the H-
point machine instead.
Alternative 4
    As a final alternative for locating the photometer laterally, we
considered specifying the test procedure such that NHTSA could place
the photometer anywhere from the driver's side A pillar up to and
including the passenger side A-pillar. This would give an extra margin
of safety with respect to glare directed at the driver and would also
ensure passengers are not glared. Or, photometers could be positioned
at the geometric center of the windshield, which would limit the range
of testing.
    We seek comment on the desirability of each of these options,
whether we should adopt one, or multiple options, and the relative
merits of each.

b. Preceding Vehicles

    For preceding vehicles, the safety concern is the ADB system could
glare the driver by shining excessive light onto the inside or outside
rearview mirrors. To measure glare on the outside rearview mirrors, we
propose placing the photometer anywhere against or directly adjacent to
the mirror's reflective surface. To measure glare on the inside
rearview mirror, we propose placing the photometer on the outside of
the rear window, laterally and vertically aligned with the interior
mirror. We are not proposing more detailed procedures for placing the
photometers because the locations of the mirrors themselves largely
determine the placement of the photometer, and we do not expect test
results to be affected by small variations in the placement of the
photometer. We seek comments on this aspect of the proposal.
4. Photometers and Photometric Measurements
    We propose that in compliance testing, NHTSA would use a sampling
rate of at least 200 Hz when recording test data. We would sample over
all the distance ranges for which we are proposing a corresponding
glare limit. Illuminance meter and data acquisition equipment would be
configured and any necessary steps would be taken to isolate
measurement of the light emitted by the ADB test vehicle. We seek
comment on the appropriateness of this minimum sampling rate, as well
as whether a maximum sampling rate should be specified and, if so, what
it should be. We also seek comment on whether there are other aspects
of the photometric equipment or measurements that should be specified.
    For each test run, illuminance data would be continuously recorded
as the ADB vehicle approached the stimulus vehicle through the range
defined for the specific test scenario being run. This inter-vehicle
distance is measured from the intersection of a horizontal plane
through the headlamp light sources, a vertical plane through the
headlamp light sources and a vertical plane through the vehicle's
centerline to the forward most point of the relevant photometric
receptor head mounted on the stimulus vehicle.
    In determining the set of recorded illuminance values we would look
at within each distance interval to determine compliance, we propose to
use the recorded values starting with (and including) the first
recorded value up to and including the last recorded illuminance value
in each distance range. Any recorded illuminance values in a distance
interval greater than the applicable glare limit for that distance
would be considered a test failure, provided the value is not a small
spike. Values above the applicable glare limit lasting no longer than
0.1 sec. or over a distance range of no longer than 1 m would not be
considered test failures. This allows for electric noise in the

photometers as well as momentary pitch changes of the test and stimulus
vehicles caused by bumps in the test track.
    The proposal differs from SAE J3069. For purposes of determining
whether an ADB system complies with the glare limits, SAE J3069
considers only illuminance values recorded at distances of 30, 60, 120,
and 155 meters, instead of sampling multiple illuminance values within
these distance ranges.\99\ Because an oncoming or preceding driver
could be glared anywhere from 15 m to 220 m, and because the real test
of an ADB system's performance is how it operates over the full
distance range within which it may be glaring other drivers, we
tentatively conclude it is necessary to sample illuminance values
throughout this full range, and not simply evaluate ADB system
performance at the four distance points at which the derived glare
limit changes. Because we are sampling illuminance within these ranges,
there is no need to use interpolation. The Agency would look only at
these recorded values and not interpolate any values in evaluating
compliance. We seek comment on these aspects of the proposal, in
particular on whether there are any safety impacts in choosing the
proposed test over the SAE approach.
---------------------------------------------------------------------------

    \99\ If there is no illuminance value recorded at a specified
distance, SAE J3069 specifies an interpolation procedure to generate
an illuminance value at that distance.
---------------------------------------------------------------------------

iii. Considerations in Determining Compliance With the Derived Glare
Limit Values
    The lower beam photometric test points in Table XIX of FMVSS No.
108, from which the proposed glare limits are derived, apply to direct
illumination from a headlamp. They do not include ambient light or
reflected light from the road surface or signs. Ambient light refers to
light emitted from a source other than the ADB system. This includes
moonlight, light pollution from nearby buildings, or light coming from
the stimulus vehicle. Reflected light refers to light from the ADB
vehicle's headlights reflected off the road or other surface into the
photometer(s) on the stimulus vehicle.
    We propose to account for light from these sources in a couple of
ways. To minimize ambient light, we propose that testing occur when the
ambient illumination recorded by the photometers is at or below 0.2
lux.\100\ We are also proposing the test only be conducted on dry
pavement as well as pavement that is not bright white to avoid intense
roadway reflections. Nevertheless, some degree of ambient light is
unavoidable. Accordingly, in testing compliance the Agency will zero
the photometers with the stimulus vehicle's headlighting system on and
the stimulus vehicle in the orientation it will be during the test (for
example, facing east). If the test involves a curve such that the
orientation of the stimulus vehicle changes during the test, the
photometers will be zeroed in the direction of the maximum ambient
light.
---------------------------------------------------------------------------

    \100\ See SAE J3069 at <IP_ADDRESS>, <IP_ADDRESS> (``No other vehicle
lighting devices shall be activated or any retro-reflective material
present and care should be taken to avoid other sources of light,
reflected or otherwise.'').
---------------------------------------------------------------------------

    There are more finely grained ways to measure ambient illumination.
For driving scenarios in which the stimulus vehicle is moving, we
could, for example, dynamically measure ambient illuminance by driving
the stimulus vehicle over the test course and continuously recording
ambient illuminance over this run. We have tentatively decided this
would be unnecessary because we are not proposing to use any roadway
illumination. We do not anticipate ambient illumination will vary
significantly at different points on a test course section used for a
particular driving scenario. We have tentatively decided there is no
need to further adjust the measured illuminance values to account for
reflected light from the ADB headlights.
    We note that FMVSS No. 108 is unusual among the FMVSSs because it
requires that lighting equipment be ``designed to conform'' to relevant
requirements, as opposed simply to comply with relevant requirements.
As we have explained in the past, when NHTSA initially proposed in 1966
that lamps ``comply'' with FMVSS No. 108, industry represented that it
could not manufacture every lamp to meet every single test point
without a substantial cost penalty unjustified by safety. NHTSA
accepted this argument. In adopting the standard, the Agency specified
that lamps be designed to comply or designed to conform with the
applicable photometric specifications. On a number of occasions since,
NHTSA has stated that it will not consider a lamp to be noncompliant if
its failure to meet a test point is random and occasional. Thus,
historically, there has never been an absolute requirement that every
motor vehicle lighting device meet every single photometric test point
to comply with Standard No. 108.\101\ Lighting equipment design,
technology, and manufacturing have evolved and advanced since the late
1960's when the Agency initially adopted the design to conform
language, and it may be arguable whether the Agency would come to the
same conclusion were it to revisit this issue. Such matters are beyond
the scope of this rulemaking. We simply note that we are proposing to
extend the design to conform language of the current FMVSS No. 108 to
the proposed requirements.
---------------------------------------------------------------------------

    \101\ See 62 FR 63416 (Nov. 28, 1997).
---------------------------------------------------------------------------

    There are other adjustments to the measured illuminance values we
could potentially make, but we have tentatively decided not to propose.
NHTSA requests comment on the following:
     Should pitch correction be addressed directly, or are the
momentary spike provisions enough to meet the goals of this rulemaking?
     SAE J3069 allows a 2.5 sec reaction time (i.e., a glare
limit may not be exceeded for more than 2.5 sec), motivated by the
``sudden appearance of an opposing or preceding vehicle due to a
cresting a hill, a vehicle entering a roadway, etc.'' Should the Agency
consider such a reaction time requirement in the regulation?
     Should the Agency specify specific photometry equipment
and/or filtering based on the test vehicle's light source technology?
Should the Agency specify different equipment to test HID, halogen,
LED, or pulse width modulated headlamps?
iv. Additional Test Parameters
1. Test Scenarios
    We are proposing a variety of different scenarios the Agency would
be able to run to test for compliance. Scenarios would be specified in
the regulatory text. For each scenario, we specify speeds of the ADB
and stimulus test vehicles, the radius of curvature of the track, the
superelevation, the orientation of the ADB and stimulus test vehicles,
and the particular vehicle maneuver tested. Values proposed for speed,
radius of curvature, and superelevation are consistent with a standard
formula used in road design specifying the relationship between these
parameters. The formula, referred to as the simplified curve formula,
is
[GRAPHIC] [TIFF OMITTED] TP12OC18.001

where f is the coefficient of friction, V is the vehicle speed, R is
the radius of curvature, and e is superelevation.\102\
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    \102\ AASHTO Green Book, pp. 3-19 to 3-20.
---------------------------------------------------------------------------

    The proposal specifies vehicle speeds of up to 70 mph, depending on
whether the test track is straight or curved (and how tight the curve
is). We propose to

use speeds up to 70 mph when testing on a straight track. We believe an
upper limit of 70 mph is reasonable because freeways and other
arterials frequently have speed limits this high. We believe that for
an ADB system to operate at a sufficient level of safety it should be
able to operate at these speeds, both because these speeds are typical
of real-world driving, as well as because safety concerns regarding
glare are magnified at higher speeds.
    We propose using a straight track or a track with a radius of
curvature from 320-380 ft. (for vehicle speeds of 25-35 mph); 730-790
ft. (for vehicle speeds of 40-45 mph); and 1100-1300 ft. (for speeds of
50-55 mph). The first range of radius of curvature corresponds to
(approximately) the smallest radius of curvature appropriate for a
vehicle traveling 25-35 mph; these speeds roughly correspond to the
minimum speed for which we propose to allow ADB activation. The second
range of radius of curvature roughly corresponds to the higher ADB
minimum activation speeds of some of the ADB-equipped vehicles the
Agency tested. Finally, to evaluate ADB performance at higher speeds,
we are proposing an 1100-1300 ft. radius taken at 50-55 mph. We
tentatively believe it is important to include actual curves because
curves may present engineering challenges to ADB systems. For example,
in oncoming situations, a curve presents an engineering challenge in
that the opposing vehicle appears from the edge of the field of view at
a close distance; in a tight curve, an oncoming vehicle will enter the
camera field of view at a closer distance than in a larger-radius
curve. Performing adequately on large-radius curves at relatively high
speeds presents a slightly different engineering challenge than
performance on tight curves at lower speeds.
    We also propose superelevation (i.e., the degree of banking of the
track) of 0 to 2%. We attempt to minimize the degree of banking because
photometry design as well as the existing and derived glare limits are
based on flat surfaces.
    We are proposing three basic maneuvers for testing compliance.
These are oncoming (where the ADB and stimulus vehicles approach each
other traveling in opposite directions); same direction/same lane
(where the stimulus vehicle precedes the ADB vehicle in the same lane);
and same direction/passing (where the stimulus vehicle begins behind
the ADB vehicle, in the adjacent lane, and then passes the ADB vehicle
from either the left or the right). During each of these maneuvers,
each vehicle would be driven within the lane and would not change
lanes. For each of these types of maneuvers, we specify the stimulus
vehicle speed, ADB vehicle speed, radius of curvature (if testing on a
curve), and superelevation with which the Agency may test.
    The proposal differs significantly from SAE J3069 in several
respects. First, as discussed above in Section VIII.b.ii, we are
proposing to test with actual vehicles and not simply test fixtures.
Second, this proposal effectively tests at higher speeds than SAE
J3069. SAE J3069 specifies a minimum speed (above the ADB activation
threshold speed) but does not specify maximum speed. Because some of
the proposed testing scenarios employ a moving stimulus vehicle as well
as a moving ADB vehicle (at speeds of up to 70 mph for both), the
proposal would require a faster reaction time from ADB systems (and, as
discussed earlier in Section VIII.b.iii, we tentatively decided not to
include a reaction time allowance). Third, the proposed test scenarios
include curves. SAE J3069 specifies a straight track and accounts for
curves by specifying test fixtures up to two lanes to either side of
the ADB test vehicle, so that ``in a straight-line encounter, an ADB
must continuously track the angular location of an opposing vehicle as
that angular position becomes progressively further from the center of
the camera's field of view with decreasing distance to the opposing
vehicle.'' We tentatively believe it is important to test on curves
because the safety effect of glare could be magnified when a vehicle is
travelling at speed on a curve. In addition, the Agency's testing
revealed that existing ADB systems may not always appropriately shade
oncoming vehicles in curves; we believe it is important to include this
scenario to ensure that ADB systems operate safely. We seek comments on
these differences, including the safety impact of adopting the proposed
test versus the SAE standard.
    The Agency has tentatively concluded that these proposed test
scenarios are objective and strike a reasonable balance between safety
and practicability. The proposal includes realistic vehicle speeds,
interactions, and road geometries. We believe it is not unreasonable to
expect an ADB system to avoid glaring other motorists in these
scenarios. We considered, but are not proposing, a broader set of
scenarios and/or test parameter values (e.g., additional radii of
curvature, testing with multiple stimulus vehicles). This would have
allowed the Agency to test with a greater degree of realism. However, a
broader range of test scenarios may have led to less confidence in the
repeatability of test results. In any case, we tentatively believe that
the proposed set of scenarios is sufficient to provide a minimum level
of safety; they include a broad range of actual vehicles on a test
track traveling at (up to) highway speeds, on curved and straight road
segments.
    At the same time, we tentatively conclude that the scenarios we are
proposing are practicable, although some scenarios might be challenging
for some ADB systems. The Agency's testing indicated that the ADB
systems we tested generally performed well on straight roads, for
oncoming and preceding glare.\103\ However, we did see some exceedances
for a stationary stimulus vehicle in this scenario, suggesting a
stationary oncoming vehicle may be more difficult for ADB systems we
tested to handle.\104\ ADB systems also generally performed well in
shading preceding vehicles on curves. We observed that ADB systems we
tested had difficulties staying within the glare limits on curves for
oncoming vehicles.\105\ It may be that on a curve the stimulus vehicle
coincides with larger horizontal angles of the beam pattern where the
intensity of light may be higher. Accordingly, it may be possible to
design headlamps so the intensity of light at these wider angles is
brought down to the proposed glare limits.
    Additionally, it might also be the case that ADB systems
experiencing test failures are not able to view, classify, and adapt to
an oncoming vehicle through a curve in a realistic high-speed
interaction. The Agency's research included testing on various curves,
but of particular applicability to this proposal are tests conducted on
a curve with a radius of 764 ft. at 62 mph. As shown in the research
report graphs,\106\ the ADB systems we tested were unable to react fast
enough to avoid providing glare well above the same vehicles' lower
beam. As part of this proposal, the Agency considered the real-world
significance of this situation and recognized 62 mph is unusually fast
for this radius of curvature. Accordingly, the Agency is proposing a
lower speed (40-45 mph), which more adequately reflects the typical
speed most drivers would approach this type of curve.
---------------------------------------------------------------------------

    \103\ ADB Test Report, p. 172.
    \104\ Id. at p. 102.
    \105\ Id. at p. 173.
    \106\ Id. at p. 192 (Fig. 84).
---------------------------------------------------------------------------

    We found that some vehicles performed well in all passing maneuver
scenarios, while other vehicles did not perform as well in certain
passing

scenarios (for example, the Audi produced high levels of glare in
straight and right curve passing maneuvers).\107\ We found that the ADB
systems generally performed well with respect to oncoming motorcycles,
but produced excessive glare in a scenario involving a preceding
motorcycle.\108\
---------------------------------------------------------------------------

    \107\ Id. at p. 173.
    \108\ Id. at p. 173.
---------------------------------------------------------------------------

    There are some common scenarios we considered but are not proposing
to test because we recognize that current ADB systems could not
reasonably be expected to perform well, or they might be difficult to
specify to ensure repeatable results. For example, the proposal does
not include testing ADB performance when approaching a vehicle at an
intersection oriented perpendicular to the ADB vehicle's direction of
travel. \109\ We have tentatively decided not to include this scenario
because NHTSA's testing indicated that existing ADB systems would have
a difficult time complying with this, and we believe the magnitude and
effect of glare in this situation would be relatively minimal because
the vehicle illuminated by the ADB system would be stopped or preparing
for a stop. Examples of other scenarios not proposed are testing with
multiple stimulus vehicles; performing more complicated vehicle
maneuvers; and performing on dips or hills (this is discussed below in
Section VIII.b.iv.5).
---------------------------------------------------------------------------

    \109\ ADB Test Report, p. 110.
---------------------------------------------------------------------------

    We seek comment on all aspects of the proposed test scenarios. Is
70 mph an appropriate maximum speed? Will it be practicable for
manufacturers to run compliance tests based on these proposed test
procedures, if they so choose to do this as a basis for their
certification?
2. Lane Width
    We also propose that any test track or road we use have a lane
width from 10 feet to 12 feet. The Federal Highway Administration
classifies roads by functional types: Arterials, collectors, and local
roads.\110\ Design speeds on arterials and collectors range from about
20 mph on up; \111\ because these roads generally provide enhanced
mobility, it is reasonable to believe speeds are generally higher than
this. Design speeds for local roads are generally lower, ranging from
about 20 to 30 mph.\112\ ADB systems are typically designed to activate
at speeds above typical city driving speeds; activation speeds of
vehicles tested by NHTSA ranged from 19 to 43 mph. Thus, ADB systems
could conceivably be used on all types of roads, although ADB would be
less likely to be used on local roads (at least in urban settings).
---------------------------------------------------------------------------

    \110\ See Highway Functional Classification Concepts, Criteria,
and Procedures, Federal Highway Administration (hereinafter
``HFCC''), available at https://www.fhwa.dot.gov/planning/processes/statewide/related/highway_functional_classifications/fcauab.pdf.
Arterials (such as interstates and expressways) generally handle
longer trips; collector roads collect and disperse traffic between
arterials and the lower level roads; and local roads provide access
function to homes, businesses, and other locations. Arterials
provide relatively high levels of mobility and less access, whereas
the opposite is true for local roads, and connectors fall in
between. Higher levels of mobility are generally associated with
higher speeds.
    \111\ AASHTO Green Book, p. 6-2 (rural collectors); AASHTO Green
Book, p. 6-11 (urban collectors); HFCC p. 43 (arterials); AASHTO
Green Book, p. 7-2 (rural arterial); AASHTO Green Book, p. 7-27
(urban arterial). Various speed ratings can be used to describe a
road--e.g., operating speed, running speed, speed limit, and design
speed. The discussion here focuses on design speed, which is ``a
selected speed used to determine the various geometric design
features of the roadway . . . [and] should be a high-percentile
value in this speed distribution curve[.]'' AASHTO Green Book, pp.
2-54 to 2-55.
    \112\ AASHTO Green Book, p. 5-2 (rural local); p. 5-11 (urban
local).
---------------------------------------------------------------------------

    While 12-foot lanes are standard on arterials such as interstates
and expressways, a sizeable proportion of collectors and local roads
(as well as other types of arterials) have narrower lanes. Arterials
and collectors together make up approximately one-third of all
roadways.\113\ About 55% of arterials and collectors have 12-ft.
lanes.\114\ However, about 33% have 10 or 11 ft. lanes.\115\ Local
roads account for approximately two-thirds of all roadways.\116\ Local
road widths generally range from 8 to 10 ft.\117\ NHTSA's testing was
conducted on several different track configurations with lane widths of
9, 10.5, and 12 feet.
---------------------------------------------------------------------------

    \113\ Highway Statistics 2014. Department of Transportation,
Federal Highway Administration, available at https://www.fhwa.dot.gov/policyinformation/statistics.cfm, Table HM-220
(miles); Table HM-260 (lane-miles). All citations to tables are from
this edition of Highway Statistics. We consider arterials and
collectors together and separately from local roads because of the
way the data is reported. If the analysis were based on vehicle
miles traveled, the result would likely be similar. See HFCC pp. 22-
23.
    \114\ Calculated from Table HM-53.
    \115\ Calculated from Table HM-53.
    \116\ Calculated from Table HM-220.
    \117\ HFCC, p. 23.
---------------------------------------------------------------------------

    We tentatively believe using lanes with widths from 10 feet to 12
feet would be adequate to cover a sufficient range of road widths the
ADB would encounter in the real world. This would allow lanes narrower
than specified in SAE J3069, which tests on a 12 foot lane, but is
consistent with the Insurance Institute for Highway Safety headlight
testing protocol, which uses a lane of 10.8 ft.\118\ We believe that
using the proposed range better reflects the range of lane widths on
roads where ADB would likely be used. The less the lateral separation
between the ADB-equipped vehicle and either oncoming or preceding
vehicles, the greater the glare risk (although differences in lateral
separation of only a couple of feet may not be expected to have a
material effect on the amount of glare). At the same time, we do not
believe it is necessary to use lanes narrower than 10 feet because at
the speeds at which ADB is operational, lane widths would not,
typically, appear to be under 10 feet. Narrower lanes might also affect
the safety of running the test.
---------------------------------------------------------------------------

    \118\ IIHS Headlight Test and Rating Protocol (November 2016),
p. 5 (3.3 m).
---------------------------------------------------------------------------

3. Number of Lanes, Median, and Traffic Barriers
    We propose to test using two adjacent lanes. The effects of glare
decrease as the angle between the glare source and the observer
increases. Accordingly, the glare risk is most acute on 2-lane
roads.\119\ A properly-functioning ADB system should be capable of
detecting and not glaring vehicles in non-adjacent lanes. However, we
tentatively conclude that if a system detects and avoids glaring in
same lane and adjacent lane scenarios, additional lanes will likely not
affect test outcomes. A median of 0 to 20 feet may separate the two
lanes. The median may include a barrier wall, but the barrier must not
be taller than 12 inches less than the mounting height of the stimulus
vehicle's headlamps.
---------------------------------------------------------------------------

    \119\ 2007 Report to Congress, pp. iv-v.
---------------------------------------------------------------------------

4. Road Surface
    We propose that the road surface be of any material (e.g.,
concrete, asphalt, etc.) but shall not be bright white. Avoiding a
bright white road surface will assist in limiting the effects of
ambient and reflected light.
    We follow SAE J3069 and specify that the road surface have an
International Roughness Index (IRI) of less than 1.5 m/km.\120\ The IRI
is an internationally recognized measure of road surface roughness; the
lower the IRI value, the smoother the road, with an IRI of 0
corresponding to a perfectly smooth road. A smooth road is important
for the proposed test because an uneven road surface can cause the ADB-
equipped vehicle to change pitch, which can lead to anomalies or spikes
in the illuminance measurements.\121\ This could lead an otherwise
compliant headlight beam to exceed the glare

limits. (The photometry requirements and the lower beam pattern are
based on a nominally level vehicle headlighting system; an increase in
vehicle pitch shifts the beam pattern up, which could glare oncoming or
preceding vehicles.)
---------------------------------------------------------------------------

    \120\ SAE J3069 7.1.
    \121\ See John D. Bullough, Nicholas P. Skinner & Timothy T.
Plummer. 2016. Assessment of Adaptive Driving Beam Photometric
Performance. SAE Technical Paper 2016-01-1408, doi:10.4271/2016-01-
1408, p. 3.
---------------------------------------------------------------------------

    An IRI value of 1.5 corresponds to a newly paved road without any
potholes, pitting, or bumps.\122\ The Federal Highway Administration
classifies roads with an IRI less than 1.5 as ``Good,'' those with an
IRI from 1.5 to 2.7 as ``Fair'', and those with an IRI greater than 2.7
as ``Poor.'' \123\ Approximately 37% of pavement miles on Federal-aid
highways were rated as having ``Good'' ride quality in 2012.\124\ This
suggests the proposed IRI value is realistically achievable on a test
track because it is realistically achievable on the much less-
controlled environments of actual roads. The vehicle test facility at
which NHTSA conducted its testing regularly measures the IRI of at
least some of its track surfaces and has generally found them to have
IRI values within the proposed range.
---------------------------------------------------------------------------

    \122\ Michael W. Sayers & Steven M. Karamihas. 1998. The Little
Book of Profiling, Basic Information About Measuring and
Interpreting Road Profiles. University of Michigan. p. 48.
    \123\ 2015 Status of the Nation's Highways, Bridges, and
Transit: Conditions and Performance, Report to Congress, Department
of Transportation, Federal Highway Administration, Federal Transit
Administration, p. 3-4, available at https://www.fhwa.dot.gov/policy/2015cpr/pdfs.cfm (last accessed Sept. 26, 2018).
    \124\ Id. p. 3-3. Many states appear to use similar
categorization. The Virginia DOT considers interstates and primary
roads with an IRI less than .95 to be ``Excellent,'' and those with
an IRI from .95 to 1.6 to be ``Good.'' Approximately one third of
interstates in Virginia were rated Excellent, and half were rated
Good. Virginia Department of Transportation. State of the Pavement
2016. pp. IV-V, available at http://www.virginiadot.org/info/resources/State_of_the_Pavement_2016.pdf (last accessed Sept. 26,
2018).
---------------------------------------------------------------------------

5. Grade of Test Road
    We propose to use a road approximating a uniform, level road, with
a longitudinal grade (slope) not exceeding 2%. We are not proposing to
test on sloped (dipped or hilly) roads. Even headlights with compliant
lower beam photometry can glare oncoming or preceding vehicles on
sloped roads because the hill geometry may place that vehicle in the
brighter portion of the lower beam pattern. NHTSA's testing was
consistent with this, showing ADB headlights and FMVSS-compliant lower
beams glared oncoming and preceding vehicles on roads with dips.\125\
It would be neither practical nor consistent with the approach of this
rulemaking (extending the existing lower beam glare requirements to ADB
systems) to require this performance of ADB systems.
---------------------------------------------------------------------------

    \125\ ADB Test Report, pp. 102, 108, 114.
---------------------------------------------------------------------------

c. Repeatability

    The Agency has collected extensive testing data and is docketing
this data. The Agency has done several different analyses of this data
to assess the repeatability of the proposed compliance test.
    One method is pooled standard deviation.\126\ Same-direction and
oncoming curve scenarios tended to have the smallest maximum pooled
standard deviation values across all four distance ranges. Also,
maneuvers involving the stimulus vehicle (also referred to here as the
``DAS'' vehicle) being stationary tended to have smaller pooled
standard deviations. This was especially true for curve maneuver
scenarios in which the DAS vehicle was stationary, likely because of
the short period of time in which the test vehicle's heading was in the
direction of the stimulus vehicle.
---------------------------------------------------------------------------

    \126\ ADB Test Report, pp. 138-146. The pooled variance is a
weighted mean of variances of individual groups, groups in this case
being the six different test vehicle/stimulus vehicle combinations.
This ignores differences in mean values for different groups and
compares only the variability within the groups. The pooed standard
deviation is the square root of this. Standard deviations calculated
by comparing all values to the overall mean are larger because that
calculation includes variability between the groups. The pooled
standard deviation method of measuring repeatability measures how
well values from one repetition to another of the same maneuver
compare to each other for any test vehicle even if the means for the
different test vehicles are different.
---------------------------------------------------------------------------

    Another method is visual analysis of data plots from each scenario
the Agency tested.\127\ These plots demonstrate each run collected data
such that the overall shape of the curve (illuminance as a function of
distance) is consistent across each test repetition. In most cases, the
deviation between data collection runs is small, and for those where
larger differences occur, differences can be reasonably attributable to
faulty sensors or lack of rigorous equipment configurations for the
particular situation such as the motorcycle photometers were not
mounted on the motorcycle itself but were on a car positioned nearby
(these data are useful for other findings but not for evaluating
repeatability). Finally, these plots allow us to evaluate the extent to
which the variability within the test itself can be reasonably
accounted for in the basic design of the ADB headlighting system. That
is to say, this method allows the Agency to evaluate the magnitude of
noise within test results as compared to proposed limits. The method of
visual analysis further supports the Agency's tentative conclusion that
the proposed test provides manufacturers with adequate notice as to the
results of any compliance testing the Agency may conduct on its
product. The Agency seeks comment on this analysis and these tentative
conclusions.
---------------------------------------------------------------------------

    \127\ ADB Test Report, pp. 147-162.
---------------------------------------------------------------------------

    The Agency further examined its research results to understand the
validity of the tests. This examination is part of the basis for which
the Agency has confidence the proposed tests can generate accurate
results and adequately distinguish between an ADB system that is likely
to expose others to excessive glare and an ADB system that will not.
Table 5 shows results of NHTSA measurements in the baseline (static)
condition in which we would expect the photometry to be the least
influenced by uncontrollable factors. This is the most basic
progression beyond testing headlamps outside of the typical photometric
lab used in most regulatory test procedures. As a general observation,
we note the mean of each static measurement is below the proposed glare
limits for each distance for a lower beam headlighting system. We also
note the upper beam illumination at 120 meters is higher than one would
expect for an FMVSS headlighting system; however, we also note all four
of these vehicles were originally designed to the UNECE standard, which
allows for considerably higher intensity upper beam headlamps.
Consistent with the information provided to us by the vehicle
manufacturer, the Mercedes-Benz and Audi vehicles' upper beam headlamps
appear to be within the FMVSS upper beam maximum limit while the other
two vehicles are likely outside of this limit. While we were unable to
do a standard laboratory photometry test on these headlamps, these data
provide confidence NHTSA measurements are reasonable.
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    Table 6 includes results of the lower beam headlamp illumination
measurements when taken through NHTSA dynamic tests including oncoming
scenarios, on a curve (right and left), and on a straightaway with the

stimulus vehicle moving and stationary. For purposes of examining the
validity of the proposed test, the Agency first considered results of
lower beam testing only to remove potential variabilities in test
results from the performance of ADB systems. The most closely
comparable measurements are the baseline and the straight maneuver as
the general orientation for these situations place the vehicle mounted
photometers in similar locations for each test. We note measurements
for dynamic situations differ from the static in positive and negative
ways meaning sometimes the dynamic test produces a higher illumination
reading, while in others, it produces a lower illumination measurement
as compared to the baseline measurement. Also of significant note, for
straight situations, the far distance (120-239.9 m range) produced
generally higher percentage differences between the baseline and the
dynamic situation. This may be expected as stray light will have a
larger percentage contribution considering the smaller base value.
Additionally, vehicle pitch variation as measured in angles would have
a larger contribution if the lower beam headlamp cutoff were to
approach photometers. This second possibility seems the less likely of
the two as dynamic measurements were not consistently higher than the
baseline measurement for that range and orientation but similar to the
other measurement ranges. Sometimes the baseline measurement was
higher, and sometimes the dynamic measurements were higher.
    Curve situations (both left and right) demonstrated a greater
difference between baseline and dynamic tests, particularly at the far
distance range. Importantly, the difference did not seem to be
compounded with the stimulus vehicle moving as opposed to stationary.
One possible explanation for the difference between baseline results
and curve results is the orientation of the two vehicles is different.
While for the straight situations photometers are in a similar place
within the test vehicles' headlamp beam pattern, for the curve
situation the vehicle orientation moves the stimulus vehicle (and
mounted photometers) out toward larger horizontal angles of the beam
pattern where the intensity of light seems to be higher in three of
these test vehicles. The BMW consistently did not demonstrate this
difference, leading the Agency to believe the test is measuring true
differences in vehicles' beam patterns even at large angles in the
curve situation. Additionally, the right curve with and without the
stimulus vehicle moving recorded similar results as the left curve with
and without the stimulus vehicle moving for each of the vehicles
tested. As such, the Agency tentatively concludes the difference
between baseline and curve situations do not demonstrate variability
within the test procedure itself but are caused by variations in beam
patterns of test vehicles. Not the topic of this section, however, this
examination leads the Agency to tentatively conclude situations in
which these far distance curves produced glare beyond tentative limits
can be designed out of headlamps.
    Considering the confidence established in the Agency's ability to
measure lower beam performance in an outdoor test on-vehicle, the
Agency next evaluated the performance of the ADB system and evaluated
the tests' ability to measure ADB headlighting systems in a dynamic
way. First, we compared oncoming straight results between lower beam
and ADB as shown in Table 7.
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    We expected the straight scenario would pose the least difficult
situation for the performance of the ADB system itself and allow the
Agency to evaluate the test. As such, we expected ADB results to be
similar to lower beam results for the same maneuver. Table 7 compares
the maximum illumination value recorded for lower beam headlamps as
compared to ADB systems and presents the quotient of the ADB divided by
the lower beam. Ideally, we would expect the quotient to equal 1. A
value less than 1 identifies results in which the ADB is dimmer than
the lower beam, while values greater than 1 identify results in which
the ADB is brighter than the lower beam. In general, the results
indicate the quotient is close to 1 with some exceptions. The far
distance range produced a quotient 2.65 on the BMW, meaning ADB system
results for that range are more than twice as bright as lower beam
results. This result is, however, a ratio of small numbers, namely 0.08
divided by 0.03. To provide context around these small numbers, the
research threshold value for that range is 0.281 (0.3 as proposed
today), much greater than recorded results for either headlighting
system. The far distance range for the Lexus vehicle produced a ratio
of 2.7 meaning ADB results are approaching three times as bright as the
lower beam. Unlike results for the BMW, the Lexus measurements are not
particularly small numbers. In fact, the ADB measurement for that test
was 0.37 lux, which is above the research threshold for the far
distance range. Interestingly, the Mercedes-Benz ADB results were
within 16% of lower beam results for all ranges corresponding to the
straight maneuver. This leads the Agency to the tentative conclusion
favorable ratios between the lower beam and ADB systems are technically
possible, and the test procedure is useful in discerning the
performance of the ADB system in the straight maneuver.
    The Agency research also included the evaluation of more complex
maneuvers and scenarios to evaluate the ADB performance in situations
that are more likely to challenge the ADB system's functionality. Table
8 presents results of the ADB system's performance on the curve
maneuver.
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    As discussed previously, the lower beam exceeded research
thresholds for the long range for all vehicles except the BMW. Beyond
this, several ADB performance aspects were observed in this test.
Again, building on the lower beam performance, the ADB performance was
evaluated as a quotient of the maximum illumination as compared to the
lower beam for each distance range. Audi results showed high quotients
for each of the curve tests for the 60-119.9 m range. Not only is the
quotient high, the maximum illumination for that range was reported as
1.61, 1.99, 2.95, and 3.23 lux as presented in the table above. To put
these values in perspective, the research threshold for that range is
0.634 lux. While the lower beam, in some cases, exceeded this
threshold, the maximum exceedance for the lower beam was a measurement
of 0.78 over the threshold by just 23% on the Audi. Based on the
confidence in the Agency's test, established in the previous
discussion, the Agency tentatively concludes differences shown on
curves are true differences in the ADB performance and not variability
in the test itself. To further establish this tentative conclusion, the
Agency looked at details of the test and plotted the illuminance as a
function of distance as shown below. Results for the oncoming curve-
left test show the passenger car stimulus vehicle and the SUV stimulus
vehicle where both the stimulus vehicle and the ADB vehicles are moving
at 62 mph.
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    By comparing the plots, we can see the ADB system is providing a
full upper beam (or at least not shading the stimulus vehicle) until
suddenly recognizing and dramatically lowering the glare (at round 70 m
for the moving passenger car stimulus vehicle and 50 m for the moving
SUV stimulus vehicle). The sudden lowering of the illuminance appears
to happen sooner for the two stationary stimulus vehicles. The Agency
tentatively considers this outcome a byproduct of the ADB system's lack
of ability to view, classify, and adapt to an oncoming vehicle through
a curve at a realistic but generally high-speed interaction. Further
support of this tentative conclusion is that for each of the curve
interactions listed above, glare measurements are higher when the
stimulus is moving as compared to when it is stopped for the 60-119.9 m
range.
    Taken together, these results support the Agency's tentative
conclusion that the proposed test is repeatable and sufficient in its
ability to measure ADB performance using a vehicle-based, dynamic test.
Further, the Agency tentatively concludes the variability in the test
is small enough that a manufacturer can reasonably anticipate results
of any compliance test the Agency would conduct if taken into
consideration during design stages of the vehicle and headlighting
system.

IX. Certification and Aftermarket

    Motor vehicle manufacturers are required to certify that their
vehicles comply with all applicable FMVSS.\128\ FMVSS No. 108 also
applies to replacement equipment (i.e., equipment sold on the
aftermarket to replace original equipment installed on the vehicle and
certified to FMVSS No. 108 at the time of the first sale to a purchaser
other than for resale).\129\ Replacement equipment must be designed to
conform to meet any applicable requirements and include all functions
of the lamp it is designed to replace or capable of replacing.\130\
Each replacement lamp which is designed or recommended for particular
vehicle models must be designed so that it does not take the vehicle
out of compliance with the standard when the individual device is
installed on the vehicle.\131\ A manufacturer of replacement equipment
is responsible for certifying that equipment.\132\ It may be the case
that only the manufacturer of the original equipment and/or vehicle
would be able to make a good faith certification of ADB replacement
equipment because requirements are vehicle-level, not equipment level.
We seek comment on this.
---------------------------------------------------------------------------

    \128\ See, e.g. 49 U.S.C. 3015.
    \129\ S3.3 (the standard applies to ``[l]amps, reflective
devices, and associated equipment for replacement of like equipment
on vehicles to which this standard applies.'').
    \130\ S<IP_ADDRESS>.
    \131\ S<IP_ADDRESS>.
    \132\ 49 U.S.C. 30115; Letter from Stephen Wood, Acting Chief
Counsel, to George Van Straten, Van Straten Heated Tail Light Co.,
Inc. (Aug. 11, 1989).
---------------------------------------------------------------------------

X. Regulatory Alternatives

    The two main regulatory alternatives NHTSA considered were the ECE
ADB requirements and SAE J3069. However, as noted earlier, the ECE
requirements are not sufficiently objective to be incorporated into an
FMVSS. Accordingly, the main regulatory alternative we considered is
SAE J3069.
    In the preceding sections of this document we discussed in detail
specific aspects in which the proposal follows and differs from SAE
J3069. In general, there are two major ways in which they differ.
    First, the proposal would require a more robust and realistic track
test to evaluate glare. This track test is the major element of the
proposed rule. It is ultimately based--as is the SAE J3069 track test--
on the glare limits developed in NHTSA's Feasibility Study. These glare
limits are the foundational element of the track test. The proposal and
SAE J3069 differ somewhat in the way the proposed glare limits are
specified, but they are largely similar. The proposal differs
significantly from SAE J3069, however, in the way that it would test
for compliance with these glare limits. SAE J3069 specifies testing on
a straight portion of road, and instead of using oncoming or preceding
vehicles, uses stationary test fixtures positioned at precisely
specified locations adjacent to the test track. The proposed test
procedure would permit the Agency to test on curved portions of road
(with various radii of curvature) using a broad range of actual FMVSS-
certified vehicles as oncoming or preceding vehicles.
    Second, the proposal would require additional laboratory-tested
equipment-level photometric requirements to regulate both glare and
visibility. With

respect to glare prevention, we propose to require that the part of the
ADB beam that is cast near other vehicles must not exceed the current
low beam maxima, and the part of an ADB beam that is cast onto
unoccupied roadway must not exceed the current upper beam maxima. SAE
J3069 requires the former but not the latter. With respect to
visibility, we propose that the part of the ADB beam that is cast near
other vehicles must comply with the current lower beam minima, and that
the part of the ADB beam that is cast onto unoccupied roadway comply
with the upper beam minima. SAE J3069 does not have any laboratory-
based requirements for the former, and for the latter specifies the low
beam minima, not the upper beam minima.
    NHTSA has tentatively concluded that the differences between the
proposal and SAE J3069 are necessary to ensure the ADB systems meet the
dual safety needs of glare prevention and visibility.
    NHTSA is particularly concerned about ensuring, to a reasonable
degree, that ADB systems do not glare other motorists. The attraction
of ADB is that it is able--if designed and functioning properly--to
provide enhanced illumination while not glaring other motorists.
However, if an ADB system does not perform as intended, it does have
the potential to glare other motorists. NHTSA is particularly concerned
about this because glare is a negative externality that might not be
sufficiently mitigated by market forces alone. Headlamp design involves
an inherent tension between forward illumination and glare. A vehicle
manufacturer's incentive, absent regulation, might be to provide
forward illumination at the expense of glare prevention because the
benefits of forward illumination are enjoyed by the vehicle owner,
while glare prevention principally benefits other motorists. NHTSA is
especially mindful of the many comments and complaints NHTSA has
received from the public expressing concerns about glare. The proposed
regulation is, therefore, largely focused on glare. This is consistent
with the current headlamp regulations, which have included photometry
requirements regulating glare since the standard's inception.
    NHTSA tentatively believes that the proposed requirements are
preferable to SAE J3069. The proposed track test would require that ADB
systems be able to negotiate a variety of real-world conditions and not
simply be engineered to recognize specified fixtures. We tentatively
believe the proposal will lead to ADB systems that prevent glare more
effectively, particularly in real-world situations where the other
vehicle enters the field of view of the ADB camera from the side and
not from a far distance. We also believe that requiring that the part
of the ADB beam that is cast near other vehicles must not exceed the
current low beam maxima, and the part of the ADB beam that is cast onto
unoccupied roadway must not exceed the current upper beam maxima would
provide further assurance against glare compared to the less stringent
SAE specifications. We tentatively conclude that the regulatory
requirements we are proposing would meet the need for vehicle safety
and would be sufficient to determine whether an ADB system was
functioning properly so as not to glare other motorists.
    While the bulk of the proposal is related to glare, and there is
reason to believe that manufacturers have an incentive to provide
sufficient forward illumination, we also include a very limited set of
laboratory tests to ensure a minimum level of visibility. NHTSA
tentatively believes that the limited set of proposed laboratory
photometric tests not included in SAE J3069 would provide important
safety assurances. These laboratory-based requirements only require
that the ADB complies with the existing photometry requirements that
ensure that minimum levels of illumination are provided. We tentatively
believe that if ADB systems did not provide these minimum levels of
illumination the driver might not have sufficient visibility.
    At the same time, we tentatively believe that more stringent
requirements relating to visibility are not necessary. Manufacturers
have a market incentive to provide drivers with sufficient
illumination. In addition, if an ADB system is malfunctioning in not
providing adequate illumination, vehicle owners can file complaints
both with the manufacturer and NHTSA. This would make it possible for
NHTSA to identify the safety concern, open a defect investigation, and,
if the investigation suggests the ADB system is defective, require the
OEM to recall and remedy the vehicle. This is largely not the case for
glare, because a motorist who is glared by another vehicle is rarely
able to identify that vehicle and submit a complaint. Moreover, we
believe potential safety benefits of ADB technology justify focusing on
what we believe is the most acute regulatory concern (glare), and not
including equally stringent requirements and test procedures related to
visibility. Based on the Agency's testing, and on the experience with
ADB systems in Europe and Asia, it appears that current systems have
generally been providing adequate illumination. However, we tentatively
believe these minimum requirements are necessary.
    A more detailed discussion of the expected likely costs and
benefits of the proposal as compared to SAE J3069 is provided below in
Section XI, Overview of Costs and Benefits.
    As an alternative to the proposed requirements and compliance test
procedures, the Agency could more closely follow SAE J3069. We earlier
discussed specific ways in which we depart from SAE J3069. We could
choose to conform to SAE J3069 with respect to some or all of these
test attributes. The major ways the proposal could further conform to
SAE J3069 would be by using stationary fixtures, instead of moving
vehicles, limiting the array of road geometries we would test with, and
not requiring the additional laboratory-based photometric requirements
not also included in SAE J3069. We could also incorporate SAE J3069 by
reference.
    We seek comment on the relative merits of the proposal and SAE
J3069 generally, and the advisability of conforming to or departing
from SAE J3069 in any of these respects. In particular, with respect to
differences between the proposal and SAE J3069: What are the relative
merits and drawbacks of each with respect to the statutory criteria of
objectivity, practicability, meeting the need for safety, and
appropriateness for the type of vehicle? NHTSA is also interested in
views regarding differences between the proposal and SAE J3069 in terms
of the repeatability of test results. NHTSA is also interested in
learning whether there are any other alternatives that should be
considered by the Agency.

XI. Overview of Benefits and Costs

    NHTSA has considered the qualitative costs and benefits of the
proposal. (For the reasons discussed in Section XI, Overview of
Benefits and Costs, NHTSA has not quantified the costs and benefits of
the proposal.) NHTSA has analyzed the qualitative costs and benefits of
the proposal compared to both the current baseline in which ADB systems
are not deployed as well as the primary regulatory alternative (SAE
J3069). Based on this analysis, NHTSA tentatively concludes that ADB
should be permitted and that the proposed requirements and test
procedures are the preferred regulatory alternative.

a. Proposal Compared to Current Baseline in Which ADB is Not Deployed

    We have tentatively concluded that the proposal to permit ADB and
subject it to requirements and test procedures to ensure that it does
not glare other motorists and provides sufficient visibility would have
greater net benefits than maintaining the status quo.
    We have tentatively determined that the proposal to permit ADB and
subject it to requirements and test procedures would lead to greater
benefits than maintaining the status quo in which ADB is not deployed.
The anticipated benefits are a decrease in fatalities and injuries
associated with crashes involving pedestrians, cyclists, animals, and
roadside objects due to the improved visibility provided by ADB. The
improved visibility is a result of increased upper beam use and an
enhanced lower beam. Although it is difficult to estimate these
benefits, NHTSA performed a data analysis to explore how driving in
better light conditions affects pedestrian and cyclist fatalities. The
analysis focused on pedestrian/cyclist fatalities and injuries under
various light conditions and explored the correlation between
pedestrian/cyclist fatalities and injuries with light conditions, as
well as several other risk factors (location, speed limit, alcohol use,
and driver distraction). The analysis used data from the Agency's
Fatality Analysis Reporting System and the National Automotive Sampling
System General Estimate System. These databases contain detailed
information on crashes involving fatalities and injuries, respectively,
including information on the conditions under which the crashes
occurred. This analysis suggests that the size of the target
population--pedestrian and cyclist fatalities that occur in darkness--
is 15,065 over 11 years or 1,370 per year. This analysis is discussed
in more detail in Appendix A. The Agency tentatively concludes this
analysis demonstrates that a properly-functioning ADB system could
provide significant safety benefits beyond that provided by existing
headlighting systems.\133\
---------------------------------------------------------------------------

    \133\ As discussed in Appendix A, the analysis requires a
variety of assumptions and, while partially accounting for some
confounding factors (such as alcohol-related crashes), is not able
to isolate the effect of darkness on crash risk. (Toyota also
estimated the target population, using a different methodology, in
its rulemaking petition.) Determining a more specific target
population is difficult because of a variety of data limitations
(e.g., headlamp state (on-off, upper-lower beam) is not known in
many of the pedestrian crashes).
---------------------------------------------------------------------------

    The possible disbenefits of this rulemaking would be any increases
in glare attributable to ADB. A properly-functioning ADB system would
not produce more glare than current headlights because it would
accurately recognize and shade oncoming and preceding vehicles. The
Agency's research testing of ADB-equipped vehicles leads NHTSA to
tentatively conclude that an ADB system that complied with the proposed
requirements would not lead to any significant increases in glare.
Accordingly, we do not expect any significant disbenefits.\134\
---------------------------------------------------------------------------

    \134\ We do recognize, as the ADB Test Report notes, that there
are situations in which ADB might not adequately perform, such as at
intersections and on dipped segments of roadway. We believe that at
intersections the safety concern is lessened because the encountered
vehicle is likely stationary. We also note that current headlights,
which are unable to actively adapt the beam, can glare other
vehicles at intersections and on dipped roads because the roadway
geometry becomes such that those vehicles are exposed to relatively
bright portions of the beam.
---------------------------------------------------------------------------

    ADB is currently not permitted by FMVSS No. 108, and is therefore
not currently available to consumers. The proposed rule, by allowing
the introduction of ADB systems, would expand the set of choices open
to consumers. ADB systems are optional, and the proposed rule in no way
restricts or imposes additional costs or requirements on any existing
technologies that consumers are currently able to purchase. Consumers
are therefore no worse off under the proposal. Because the proposal
expands the set of consumer choices (compared to the status quo), it is
an enabling regulation. The estimated cost savings of an enabling
regulation would include the full opportunity costs of the previously
foregone activities (i.e., the sum of consumer and producer surplus,
minus any fixed costs).
    Because we expect positive benefits and cost savings from enabling
the use of new technologies, we tentatively conclude that the proposal
would lead to higher net benefits compared to the status quo. We seek
comment on the potential benefits and cost savings of this proposal,
including quantitative data that could help estimate their magnitude.

b. Proposal Compared to SAE J3069

    NHTSA also compared the proposal to SAE J3069. As discussed below,
although the proposal is likely more costly (due to higher compliance
testing and equipment costs), these higher costs are likely outweighed
by the higher safety-related benefits (and lower glare disbenefits).
    The proposal would likely result in greater benefits than the
regulatory alternative because the proposed requirements require more
illumination (but not at levels that would glare other motorists).
Above we broadly estimated the size of the target population. We
tentatively believe that the proposed requirements would be more
effective--i.e., more likely to lead to a greater reduction in
crashes--than SAE J3069 because the proposal would require ADB systems
to provide more illumination. Two of the proposed laboratory-based
photometric requirements do this. We propose that the part of the ADB
beam that is cast near other vehicles must comply with the current
lower beam minima, and that the part of the ADB beam that is cast onto
unoccupied roadway comply with the upper beam minima. SAE J3069 does
not have any laboratory-based requirements for the former, and for the
latter specifies the lower beam minima, not the upper beam minima. We
believe the proposed requirements would offer meaningful safety
assurances. The lower and upper beam minima have been in place for
decades. They indicate what have been the longstanding minimum
acceptable levels of illumination for adequate visibility. Along with
this, they provide an appropriate tradeoff between illumination and
glare. While requiring the lower beam minima for the dimmed portion of
the ADB beam may not provide much benefit when the ADB system is
dimming portions on an oncoming or proceeding vehicle, any activation
of the dimmed region due to a false positive (dimming for a lamp post
or sign) could have safety implications (because there would not be
another vehicle's headlamps to illuminate the road). Because SAE J3069
does not require ADB systems to meet any minima within the dimmed
portion of the ADB beam, it could lead to insufficient illumination. On
the other hand, it might be possible that the more demanding road test
we propose to test for glare could incentivize manufacturers to equip
vehicles with ADB systems that provide less illumination (to ensure
that they do not fail the glare road test) than they would if we adopt
requirements more similar to SAE J3069. However, we tentatively believe
the proposed requirements will result in a greater reduction in crashes
due to increased illumination.\135\
---------------------------------------------------------------------------

    \135\ The proposal and the alternative both are most likely to
be cost-effective using the DOT's $9.7 million value of a
statistical life. However, due to the relatively more stringent
performance requirements of the proposal, it would likely accrue
more safety benefits than does the alternative.

---------------------------------------------------------------------------

    The Agency has also tentatively concluded that the proposed
requirements would lead to smaller disbenefits in terms of glare than
the regulatory alternatives, for two reasons. First, the proposal
requires a much more realistic road test to evaluate glare, including
actual vehicles and curved portions of the roadway, instead of fixtures
simulating vehicles and curves. This would require that ADB systems be
able to meet a variety of real world conditions and not simply be
engineered to recognize specified fixtures. We tentatively believe this
will lead to less glare, particularly in real-world situations where
the other vehicle enters the field of view of the ADB camera from the
side and not from a far distance (such as situations in which the ADB-
equipped vehicle is overtaken or encounters an oncoming vehicle on a
small-radius curve). Second, the proposal would require that in the
undimmed portion of the ADB beam the current upper beam maxima be met;
SAE J3069 does not specify any maxima. The upper beam maxima limit the
amount of light projected on objects that are not detected by the ADB
system such as cyclists, pedestrians, and houses near the road.
    NHTSA tentatively concludes that the proposed rule would likely
have higher costs than SAE J3069. This is due to compliance testing
costs, and, possibly, to component costs.
    We would expect higher costs for compliance testing. The proposed
road test for compliance with the proposed glare limits is more complex
than the testing required by SAE J3069 because it involves actual test
vehicles and more scenarios. The proposal also includes requirements
for static photometry testing that are not included in SAE J3069. If a
manufacturer concluded that testing was necessary to certify an ADB
system, then testing for compliance with the proposal would be more
costly than compliance testing for a standard more closely based on SAE
J3069.
    We do not expect design and development costs to be significantly
higher than they would be under SAE J3069. ADB is currently offered as
an optional system in Europe, among other markets. We tentatively
believe that the European ADB (if modified to produce a U.S.-compliant
beam \136\) systems are essentially capable of complying with the
proposed requirements. The Agency tested a variety of European vehicles
in a road test similar to the one that is proposed today to measure
glare. The vehicles passed many of the scenarios we tested, although we
observed that the ADB systems had difficulties staying within the glare
limits when encountering oncoming vehicles on curves when both vehicles
were travelling at approximately 60 mph. In consideration of these test
results, the proposal does not include any tests on curves at these
higher speeds. (In the proposal, we are proposing that the vehicle's
speeds not exceed 45 mph in this scenario.)
---------------------------------------------------------------------------

    \136\ Because the headlamp photometry requirements in FMVSS No.
108 differ from ECE-required photometry, in order for an ECE-
compliant system to be sold in the U.S., the headlamp photometry
would need to be modified, which would entail some design cost. This
is true for any European-model vehicle sold in the U.S.
---------------------------------------------------------------------------

    However, we do believe that it could be more costly to equip a
vehicle with an ADB system that complies with the proposal rather than
with the minimum requirements of SAE J3069. For instance, the proposal
requires that the undimmed portion of the ADB beam meet the current
upper beam minima. The European systems we tested similarly used the
upper beam (ECE driving beam) to illuminate regions outside the dimmed
portion of the beam. SAE J3069, however, requires only that the lower
beam minima be met in this region. Accordingly, an SAE J3069-compliant
system could use a lower cost light source. As another example, while
the European systems NHTSA tested employed relatively sophisticated LED
arrays or shading devices, a system that complied with the minimum
requirements of SAE J3069 could employ less sophisticated technology.
    NHTSA has tentatively concluded that the likely additional (i.e.,
as compared to SAE J3069) benefits associated with the proposal exceed
the likely additional costs of the proposal. The somewhat greater costs
it would require to equip a vehicle with an ADB system that complies
with the proposed requirements would likely be outweighed by the
greater benefits (and smaller glare disbenefits) that we tentatively
believe would be likely to result from the proposal. For instance, a
system that saved money on a narrow field of view camera would not
provide glare protection on small radius curves in real world driving.
Additionally, any cost savings to be gained from a less intense light
source used for the undimmed portion of the beam would be negated by
the relative increase risk to pedestrian detection.
    NHTSA seeks comment on all these issues, in particular the relative
costs of compliance with the proposal, SAE J3069, and the ECE
requirements (especially specific data and cost estimates), as well as
the relative benefits of these alternatives.

XII. Rulemaking Analyses

Executive Order 13771

    Executive Order 13771 titled ``Reducing Regulation and Controlling
Regulatory Costs,'' directs that, unless prohibited by law, whenever an
executive department or Agency publicly proposes for notice and comment
or otherwise promulgates a new regulation, it shall identify at least
two existing regulations to be repealed. In addition, any new
incremental costs associated with new regulations shall, to the extent
permitted by law, be offset by the elimination of existing costs. Only
those rules deemed significant under section 3(f) of Executive Order
12866, ``Regulatory Planning and Review,'' are subject to these
requirements. As discussed below, this rule is not a significant rule
under Executive Order 12866. However, this proposed rule is expected to
be an E.O. 13771 deregulatory action. Details on the estimated cost
savings of this proposed rule can be found in the rule's economic
analysis.

Executive Order 12866, Executive Order 13563, and DOT Regulatory
Policies and Procedures

    Executive Order 12866, Executive Order 13563, and the Department of
Transportation's regulatory policies require determinations as to
whether a regulatory action is ``significant'' and therefore subject to
OMB review and the requirements of the aforementioned Executive Orders.
Executive Order 12866 defines a ``significant regulatory action'' as
one that is likely to result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more or
adversely affect in a material way the economy, a sector of the
economy, productivity, competition, jobs, the environment, public
health or safety, or State, local, or Tribal governments or
communities;
    (2) Create a serious inconsistency or otherwise interfere with an
action taken or planned by another agency;
    (3) Materially alter the budgetary impact of entitlements, grants,
user fees, or loan programs or the rights and obligations of recipients
thereof; or
    (4) Raise novel legal or policy issues arising out of legal
mandates, the President's priorities, or the principles set forth in
the Executive Order.
    We have considered the potential impact of this proposal under
Executive Order 12866, Executive Order 13563, and the Department of
Transportation's regulatory policies and procedures. This NPRM is not
significant and so was not reviewed under E.O. 12866.

    However, pursuant to E.O. 12866 and the Department's policies, we
have identified the problem this NPRM intends to address, considered
whether existing regulations have contributed to the problem, and
considered alternatives. Because this rulemaking has been designated
nonsignificant, quantification of benefits is not required under E.O.
12866, but is required, to the extent practicable, under DOT Order
2100.5. NHTSA has tentatively determined that quantifying the benefits
and costs is not practicable in this rulemaking.
    Quantifying the benefits of the proposal--the decrease in deaths
and injuries due to the greater visibility made possible by ADB--is
difficult because of a variety of data limitations related to
accurately estimating the target population and the effectiveness of
ADB. For example, headlamp state (on-off, upper-lower beam) is not
reflected in the data for many of the pedestrian crashes. Nevertheless,
we attempt to broadly estimate the magnitude of the target population
in Appendix A. (Toyota's rulemaking petition also includes a target
population analysis using a different methodology.)
    Quantification of costs is similarly not practicable. The only
currently-available ADB systems are in foreign markets such as Europe.
We tentatively believe that an ECE-approved ADB system (modified to
have FMVSS 108-compliant photometry) would be able to comply with the
proposed requirements. It would be possible for NHTSA to estimate the
cost of such systems by performing teardown studies, but we have not
done so. Among other reasons, even if NHTSA performed tear-down studies
for ECE-approved systems, NHTSA would still need to estimate the cost
of the compliance with the main regulatory alternative, SAE J3069.
However, there are not any SAE J3069-compliant systems on the market to
use in a tear-down cost analysis because ADB systems are not currently
available in the U.S. It might be possible for NHTSA to estimate the
costs of an SAE J3069-compliant system with an engineering assessment,
but such an assessment would require additional time and resources.
    We therefore tentatively conclude that a quantitative cost-benefit
analysis is not currently practicable. We believe that a qualitative
analysis (see Section XI, Overview of Benefits and Costs) is sufficient
to reasonably conclude that the proposed requirements are preferable to
the current regulatory alternative.

Executive Order 13609: Promoting International Regulatory Cooperation

    The policy statement in section 1 of Executive Order 13609
provides, in part:

    The regulatory approaches taken by foreign governments may
differ from those taken by U.S. regulatory agencies to address
similar issues. In some cases, the differences between the
regulatory approaches of U.S. agencies and those of their foreign
counterparts might not be necessary and might impair the ability of
American businesses to export and compete internationally. In
meeting shared challenges involving health, safety, labor, security,
environmental, and other issues, international regulatory
cooperation can identify approaches that are at least as protective
as those that are or would be adopted in the absence of such
cooperation. International regulatory cooperation can also reduce,
eliminate, or prevent unnecessary differences in regulatory
requirements.

    Although this proposal is different than comparable foreign
regulations, we believe that the proposed requirements have the
potential to enhance safety.

Executive Order 13132 (Federalism)

    NHTSA has examined this proposed rule pursuant to Executive Order
13132 (64 FR 43255; Aug. 10, 1999) and concluded that no additional
consultation with States, local governments, or their representatives
is mandated beyond the rulemaking process. The Agency has concluded
that the rule does not have sufficient federalism implications to
warrant consultation with State and local officials or the preparation
of a federalism summary impact statement. The rule does not have
``substantial direct effects on the States, on the relationship between
the national government and the States, or on the distribution of power
and responsibilities among the various levels of government.''
    NHTSA rules can have preemptive effect in two ways. First, the
National Traffic and Motor Vehicle Safety Act contains an express
preemption provision: When a motor vehicle safety standard is in effect
under this chapter, a State or a political subdivision of a State may
prescribe or continue in effect a standard applicable to the same
aspect of performance of a motor vehicle or motor vehicle equipment
only if the standard is identical to the standard prescribed under this
chapter. 49 U.S.C. 30103(b)(1). It is this statutory command by
Congress that preempts any non-identical State legislative and
administrative law address the same aspect of performance.
    The express preemption provision described above is subject to a
savings clause under which ``[c]ompliance with a motor vehicle safety
standard prescribed under this chapter does not exempt a person from
liability at common law.'' 49 U.S.C. 30103(e) Pursuant to this
provision, State common law tort causes of action against motor vehicle
manufacturers that might otherwise be preempted by the express
preemption provision are generally preserved. However, the Supreme
Court has recognized the possibility, in some instances, of implied
preemption of State common law tort causes of action by virtue of
NHTSA's rules--even if not expressly preempted.
    This second way that NHTSA rules can preempt is dependent upon the
existence of an actual conflict between an FMVSS and the higher
standard that would effectively be imposed on motor vehicle
manufacturers if someone obtained a State common law tort judgment
against the manufacturer--notwithstanding the manufacturer's compliance
with the NHTSA standard. Because most NHTSA standards established by an
FMVSS are minimum standards, a State common law tort cause of action
that seeks to impose a higher standard on motor vehicle manufacturers
will generally not be preempted. However, if and when such a conflict
does exist--for example, when the standard at issue is both a minimum
and a maximum standard--the State common law tort cause of action is
impliedly preempted. See Geier v. American Honda Motor Co., 529 U.S.
861 (2000).
    Pursuant to Executive Order 13132, NHTSA has considered whether
this proposed rule could or should preempt State common law causes of
action. The Agency's ability to announce its conclusion regarding the
preemptive effect of one of its rules reduces the likelihood that
preemption will be an issue in any subsequent tort litigation.
    To this end, the Agency has examined the nature (e.g., the language
and structure of the regulatory text) and objectives of this proposed
rule and does not foresee any potential State requirements that might
conflict with it. We do note that many or most states have laws that
regulate lower and upper beam use. These laws require that a motorist
use a lower beam within a certain distance of an oncoming or preceding
vehicle. We do not believe that there is a conflict between the
proposed rule and these laws because the proposed rule would allow an
additional type of lower beam. A vehicle equipped with a compliant and
properly functioning ADB system should not glare other vehicles, as
long

as the proposed requirements are sufficient to meet the goals of this
proposal--i.e., to protect oncoming and preceding motorists from glare.
NHTSA does not intend that this proposed rule preempt state tort law
that would effectively impose a higher standard on motor vehicle
manufacturers than that established by this rule. Establishment of a
higher standard by means of State tort law would not conflict with the
standards proposed in this NPRM. Without any conflict, there could not
be any implied preemption of a State common law tort cause of action.

National Environmental Policy Act

    The National Environmental Policy Act of 1969 (NEPA) (42 U.S.C.
4321-4347) requires Federal agencies to analyze the environmental
impacts of proposed major Federal actions significantly affecting the
quality of the human environment, as well as the impacts of
alternatives to the proposed action. 42 U.S.C. 4332(2)(C). When a
Federal agency prepares an environmental assessment, the Council on
Environmental Quality (CEQ) NEPA implementing regulations (40 CFR parts
1500-1508) require it to ``include brief discussions of the need for
the proposal, of alternatives [. . .], of the environmental impacts of
the proposed action and alternatives, and a listing of agencies and
persons consulted.'' 40 CFR 1508.9(b). This section serves as the
Agency's Draft Environmental Assessment (Draft EA). NHTSA invites
public comments on the contents and tentative conclusions of this Draft
EA.
Purpose and Need
    This notice of proposed rulemaking sets forth the purpose of and
need for this action. As explained earlier in this preamble, ADB
technology improves safety by providing a variable, enhanced lower beam
pattern that is sculpted to traffic on the road, rather than just one
static lower beam pattern, thereby providing more illumination without
glare to other motorists. In addition, ADB technology will likely lead
to increased upper beam use, thereby improving driver visibility
distance at higher speeds. In this document, NHTSA tentatively
concludes that FMVSS No. 108 does not currently permit ADB technology.
This proposal therefore reconsiders the currently-existing standard by
addressing the safety needs of visibility and glare prevention to
improve safety. This proposal considers and invites comment on how best
to ensure that ADB technology improves visibility without increasing
glare.
Alternatives
    NHTSA has considered a range of regulatory alternatives for the
proposed action. Under a ``no action alternative,'' NHTSA would not
issue a final rule amending FMVSS No. 108, and ADB technology would
continue to be prohibited. NHTSA has also considered the ECE
requirements and SAE J3069, which are described above in this preamble.
Under this proposal, NHTSA incorporates elements from these standards,
but departs from them in significant ways, which are also described
above. NHTSA invites public comments on its proposal.
Environmental Impacts of the Proposed Action and Alternatives
    This proposed action is anticipated to result in increased upper
beam use as well as greater illumination from lower beams (albeit in
patterns designed to prevent glare to other motorists). As a result,
the primary environmental impacts anticipated to result from this
rulemaking are associated with light pollution, including the potential
disruption of wildlife adjacent to roadways. The National Park Service
(NPS) defines ``light pollution'' as the introduction of artificial
light, either directly or indirectly, into the natural
environment.\137\ Forms of light pollution include sky glow (the bright
halo over urban areas at nighttime), light trespass (unintended
artificial lighting on areas that would otherwise be dark), glare
(light shining horizontally), and overillumination (excess artificial
lighting for a specific activity).\138\ Light pollution caused by
artificial light can have various effects on flora and fauna, including
disrupting seasonal variations and circadian rhythms, disorientation
and behavioral disruption, sleep disorders, and hormonal
imbalances.\139\
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    \137\ National Park Service, Light Pollution. https://www.nps.gov/subjects/nightskies/lightpollution.htm (last accessed
Sept. 26, 2018).
    \138\ Chepesiuk, R. 2009. Missing the Dark: Health Effects of
Light Pollution. Environmental Health Perspectives, 117(1), A20-A27.
    \139\ Id.
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    Although this rule is anticipated to result in increased levels of
illumination caused by automobiles at nighttime, NHTSA does not believe
these levels would contribute appreciably to light pollution in the
United States. First, the Agency proposes to require that the part of
an ADB beam that is cast near other vehicles not exceed the current low
beam maxima and the part of an ADB beam that is cast onto unoccupied
roadway not exceed the current upper beam maxima. Although overall
levels of illumination are expected to increase from current levels due
to increased high beam use and the sculpting of lower beams to traffic
on the road, total potential brightness would not be permitted to
exceed the potential maxima that already exists on motor vehicles
today. These maxima would not only reduce the potential for glare to
other drivers, but would also limit the potential impact of light
pollution.
    Second, we note that ADB systems remain optional under the
proposal. Because of the added costs associated with the technology,
NHTSA does not anticipate that manufacturers would make these systems
standard equipment in all of their vehicle models at this time. Thus,
only a percentage of the on-road fleet would feature ADB systems, while
new vehicles without the systems would be anticipated to continue to
have levels of illumination at current rates.
    Third, while ADB systems generally would increase horizontal
illumination, they likely would not contribute to ambient light
pollution to the same degree as other forms of illumination, such as
streetlights and building illumination, where light is intentionally
scattered to cover large areas or wasted due to inefficient design,
likely contributing more to the nighttime halo effect in populated
areas. According to NPS, the primary cause of light pollution is
outdoor lights that emit light upwards or sideways (but with an upwards
angle).\140\ As the light escapes upward, it scatters throughout the
atmosphere and brightens the night sky. Lighting that is directed
downward, however, contributes significantly less to light pollution.
Lower beams generally direct light away from oncoming traffic and
downward in order to illuminate the road and the environs close ahead
of the vehicle while minimizing glare to other road users. As a result,
any increases in lower beam illumination are not anticipated to
contribute meaningfully to light pollution. As discussed further in the
next paragraph, increases in upper beam illumination would be
anticipated largely in less populated areas, where oncoming traffic is
less frequent and small sources of artificial light (such as motor
vehicles) likely would not change ambient light levels at nighttime to
a meaningful degree.
---------------------------------------------------------------------------

    \140\ NPS, Light Pollution Sources. https://www.nps.gov/subjects/nightskies/sources.htm (last accessed Sept. 26, 2018).
---------------------------------------------------------------------------

    Fourth, NHTSA believes that the areas that would see the greatest
relative increase in nighttime illumination are predominantly rural and
unlikely to experience widespread impacts. The

Agency's proposal would require ADB systems to produce a base lower
beam at speeds below 25 mph. These slower speeds are anticipated
primarily in crowded, urban environments where the current impacts of
light pollution are likely the greatest. As a result, such urban
environments would not experience changes in light levels produced from
motor vehicles as a result of this proposal. In moderately crowded,
urban environments, nighttime vehicles may travel above 25 mph, thereby
engaging the ADB system. However, in those cases, upper beam use would
likely be low, as the high level of other road users would cause the
ADB system to rely on lower beams for visibility in order to reduce
glare for other drivers. These areas may experience small increases in
light pollution as the upper beams occasionally engage, as well as
increased illumination associated with lower beam shaping by the ADB
system. In rural areas, where traffic levels are lower and driving
speeds may be higher, the use of ADB systems is anticipated to result
in increased upper beam use. However, the low traffic levels would
result in only moderate additional light output, and the low quantity
of artificial light sources in general would mean that light pollution
levels overall would be anticipated to remain low.
    The proposed action is anticipated to improve visibility without
glare to other drivers. In addition to the potential safety benefits
associated with reduced crashes, this rule could result in fewer
instances of collisions involving animals on roadways. Upper beams are
used primarily for distance illumination when not meeting or closely
following another vehicle. Increased upper beam use in poorly lit
environments, such as rural roadways, may allow drivers increased time
to identify roadway hazards (such as animals) and to stop, slow down,
or avoid a collision.
    In addition, the impact of added artificial light on wildlife
located near roadways would depend on where and how long the additional
illumination occurs, whether or not wildlife is present within a
distance to detect the light, and the sensitivity of wildlife to the
illumination level of the added light. Wildlife species located near
active roadways have likely acclimated to the light produced by passing
vehicles, including light associated with upper beams (which would be
the same under the proposal in terms of brightness, directionality, and
shape as under current regulations). Any additional disruption caused
by increased use of upper beams is not feasible to quantify due to the
extensive number of variables associated with ADB use and wildlife.
    NHTSA is unable to comparatively evaluate the potential light
pollution impacts of the proposal compared to the other regulatory
alternatives (ECE requirements and SAE J3069). For example, the
proposal requires that the undimmed portion of the adaptive beam meet
the upper beam minima and the dimmed portion of the beam meet the lower
beam minima. The SAE standard does not establish minima for either
condition. However, NHTSA also proposes that the undimmed portion of
the beam may not exceed the upper beam maxima, whereas the SAE standard
does not specify an upper beam maxima for the undimmed portion. Thus,
while NHTSA proposes more stringent requirements for ADB systems, the
wide variations still permitted under the proposal and the SAE
standards make it difficult to compare them with any level of
certainty. However, to the degree to which ABD systems would function
similarly under each of those standards, the environmental impacts
would be anticipated to be similar.
    NHTSA seeks comment on its analysis of the potential environmental
impacts of its proposal, which will be reviewed and considered in the
preparation of a Final EA.
Agencies and Persons Consulted
    This preamble describes the various materials, persons, and
agencies consulted in the development of the proposal.
Tentative Conclusion
    NHTSA has reviewed the information presented in this Draft EA and
tentatively concludes that the proposed action would not contribute in
a meaningful way to light pollution as compared to current conditions.
Any of the impacts anticipated to result from the alternatives under
consideration are not expected to rise to a level of significance that
necessitates the preparation of an Environmental Impact Statement.
Based on the information in this Draft EA and assuming no additional
information or changed circumstances, NHTSA expects to issue a Finding
of No Significant Impact (FONSI). Such a finding will not be made
before careful review of all public comments received. A Final EA and a
FONSI, if appropriate, will be issued as part of the final rule.

Executive Order 12988 (Civil Justice Reform)

    With respect to the review of the promulgation of a new regulation,
section 3(b) of Executive Order 12988, ``Civil Justice Reform'' (61 FR
4729, February 7, 1996) requires that Executive agencies make every
reasonable effort to ensure that the regulation: (1) Clearly specifies
the preemptive effect; (2) clearly specifies the effect on existing
Federal law or regulation; (3) provides a clear legal standard for
affected conduct, while promoting simplification and burden reduction;
(4) clearly specifies the retroactive effect, if any; (5) adequately
defines key terms; and (6) addresses other important issues affecting
clarity and general draftsmanship under any guidelines issued by the
Attorney General. This document is consistent with that requirement.
    Pursuant to this Order, NHTSA notes as follows. The issue of
preemption is discussed above in connection with E.O. 13132. NHTSA
notes further that there is no requirement that individuals submit a
petition for reconsideration or pursue other administrative proceeding
before they may file suit in court.

Regulatory Flexibility Act

    Pursuant to the Regulatory Flexibility Act (5 U.S.C. 601 et seq.,
as amended by the Small Business Regulatory Enforcement Fairness Act
(SBREFA) of 1996), whenever an agency is required to publish an NPRM or
final rule, it must prepare and make available for public comment a
regulatory flexibility analysis (RFA) that describes the effect of the
rule on small entities (i.e., small businesses, small organizations,
and small governmental jurisdictions). The Small Business
Administration's regulations at 13 CFR part 121 define a small
business, in part, as a business entity ``which operates primarily
within the United States.'' (13 CFR 121.105(a)). No regulatory
flexibility analysis is required if the head of an agency certifies
that the rule will not have a significant economic impact on a
substantial number of small entities. The SBREFA amended the Regulatory
Flexibility Act to require Federal agencies to provide a statement of
the factual basis for certifying that a rule will not have a
significant economic impact on a substantial number of small entities.
    NHTSA has considered the effects of this rulemaking action under
the Regulatory Flexibility Act. According to 13 CFR 121.201, the Small
Business Administration's size standards regulations used to define
small business concerns, manufacturers of the vehicles covered by this
proposed rule would fall under North American Industry Classification
System (NAICS) No. 336111, Automobile Manufacturing,

which has a size standard of 1,000 employees or fewer.
    NHTSA estimates that there are six small light vehicle
manufacturers in the U.S. We estimate that there are eight headlamp
manufacturers that could be impacted by a final rule. I hereby certify
that if made final, this proposed rule would not have a significant
economic impact on a substantial number of small entities. Most of the
affected entities are not small businesses. The proposed rule, if
adopted, will not establish a mandatory requirement on regulated
persons.

National Technology Transfer and Advancement Act

    Under the National Technology Transfer and Advancement Act of 1995
(NTTAA) (Pub. L. 104-113), ``all Federal agencies and departments shall
use technical standards that are developed or adopted by voluntary
consensus standards bodies, using such technical standards as a means
to carry out policy objectives or activities determined by the agencies
and departments.'' Voluntary consensus standards are technical
standards (e.g., materials specifications, test methods, sampling
procedures, and business practices) that are developed or adopted by
voluntary consensus standards bodies, such as the Society of Automotive
Engineers (SAE). The NTTAA directs this Agency to provide Congress,
through OMB, explanations when the Agency decides not to use available
and applicable voluntary consensus standards.
    SAE International has published a voluntary consensus standard (SAE
J3069 JUN2016) for ADB systems. The foregoing sections of this document
discuss in detail areas in which we follow or depart from SAE J3069.

Paperwork Reduction Act

    Under the Paperwork Reduction Act of 1995 (PRA) (44 U.S.C. 3501, et
seq.), Federal agencies must obtain approval from the Office of
Management and Budget (OMB) for each collection of information they
conduct, sponsor, or require through regulations. This rulemaking would
not establish any new information collection requirements.

Unfunded Mandates Reform Act

    The Unfunded Mandates Reform Act of 1995 (Pub. L. 104-4) (UMRA)
requires agencies to prepare a written assessment of the costs,
benefits, and other effects of proposed or final rules that include a
Federal mandate likely to result in the expenditures by States, local
or tribal governments, in the aggregate, or by the private sector, of
more than $100 million annually (adjusted annually for inflation with
base year of 1995). Adjusting this amount by the implicit gross
domestic product price deflator for 2013 results in $142 million
(109.929/75.324 = 1.42). The assessment may be included in conjunction
with other assessments, as it is here.
    This proposed rule is not likely to result in expenditures by
State, local or tribal governments of more than $100 million annually.
    UMRA requires the Agency to select the ``least costly, most cost-
effective or least burdensome alternative that achieves the objectives
of the rule.'' As discussed above, the Agency considered alternatives
to the proposed rule. We have tentatively concluded that none of the
alternatives are preferable to the alternative proposed by the NPRM. We
have tentatively concluded that the requirements we are proposing today
are the most cost-effective alternatives that achieve the objectives of
the rule.

Plain Language

    Executive Order 12866 and E.O. 13563 require each agency to write
all rules in plain language. Application of the principles of plain
language includes consideration of the following questions:
     Have we organized the material to suit the public's needs?
     Are the requirements in the rule clearly stated?
     Does the rule contain technical language or jargon that
isn't clear?
     Would a different format (grouping and order of sections,
use of headings, paragraphing) make the rule easier to understand?
     Would more (but shorter) sections be better?
     Could we improve clarity by adding tables, lists, or
diagrams?
     What else could we do to make the rule easier to
understand?
    If you have any responses to these questions, please include them
in your comments on this proposal.

Regulation Identifier Number (RIN) 2127-AL83

    The Department of Transportation assigns a regulation identifier
number (RIN) to each regulatory action listed in the Unified Agenda of
Federal Regulations. The Regulatory Information Service Center
publishes the Unified Agenda in April and October of each year. You may
use the RIN contained in the heading at the beginning of this document
to find this action in the Unified Agenda.

Privacy Act

    Anyone is able to search the electronic form of all comments
received into any of our dockets by the name of the individual
submitting the comment (or signing the comment, if submitted on behalf
of an association, business, labor union, etc.). You may review DOT's
complete Privacy Act Statement in the Federal Register published on
April 11, 2000 (65 FR 19477-78).

XIII. Public Participation

How do I prepare and submit comments?

    Your comments must be written and in English. To ensure your
comments are correctly filed in the Docket, please include the docket
number of this document in your comments.
    Please organize your comments so they appear in the same order as
the topic to which they respond appears in the preamble. Please number
comments as they are numbered in the preamble. For example, a comment
concerning the placement of the photometer on an oncoming vehicle might
be labeled ``VIII.b.ii.3.a--Photometer Placement for Oncoming
Vehicles,'' or ``VIII.b.ii.3--Photometer Placement.''