Document ID: NHTSA-2022-0013-0001
Agency: nhtsa
Document Type: Rule
Title: Federal Motor Vehicle Safety Standards: Lamps, Reflective Devices, and Associated Equipment, Adaptive Driving Beam Headlamps
Posted Date: 2022-02-22T05:00Z

[Federal Register Volume 87, Number 35 (Tuesday, February 22, 2022)]
[Rules and Regulations]
[Pages 9916-10026]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-02451]

[[Page 9915]]

Vol. 87

Tuesday,

No. 35

February 22, 2022

Part V

Department of Transportation

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National Highway Traffic Safety Administration

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49 CFR Part 571

Federal Motor Vehicle Safety Standards; Lamps, Reflective Devices, and 
Associated Equipment, Adaptive Driving Beam Headlamps; Final Rule

  Federal Register / Vol. 87, No. 35 / Tuesday, February 22, 2022 / 
Rules and Regulations  

[[Page 9916]]

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DEPARTMENT OF TRANSPORTATION

National Highway Traffic Safety Administration

49 CFR Part 571

[Docket No. NHTSA-2022-0013]
RIN 2127-AL83

Federal Motor Vehicle Safety Standards; Lamps, Reflective 
Devices, and Associated Equipment, Adaptive Driving Beam Headlamps

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

ACTION: Final rule.

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SUMMARY: This document amends NHTSA's lighting standard to permit the 
certification of adaptive driving beam (ADB) headlamps. ADB headlamps 
utilize technology that actively modifies a vehicle's headlamp beams to 
provide more illumination while not glaring other vehicles. The 
requirements adopted today are intended to amend the lighting standard 
to permit this technology and establish performance requirements for 
these systems to ensure that they operate safely. ADB has the potential 
to reduce the risk of crashes by increasing visibility without 
increasing glare. The agency initiated this rulemaking in response to a 
petition for rulemaking from Toyota Motor North America, Inc.

DATES: 
    Effective date: The effective date of this final rule is February 
22, 2022. The incorporation by reference of certain publications listed 
in the rule was approved by the Director of the Federal Register as of 
February 6, 2012.
    Compliance date: The compliance date for the amendments in this 
final rule is February 22, 2022.
    Petitions for reconsideration: Petitions for reconsideration of 
this final rule must be received not later than April 8, 2022.

ADDRESSES: Petitions for reconsideration of this final rule must refer 
to the docket and notice number set forth above and be submitted to the 
Administrator, National Highway Traffic Safety Administration, 1200 New 
Jersey Avenue SE, Washington, DC 20590. Note that all petitions 
received will be posted without change to www.regulations.gov, 
including any personal information provided.
    Privacy Act: Please see the Privacy Act heading under Rulemaking 
Analyses and Notices.

FOR FURTHER INFORMATION CONTACT: Mr. Markus Price, NHTSA Office of 
Crash Avoidance Standards. Telephone: 202-366-1810; Email: 
[email protected]; or Mr. John Piazza, Office of Chief Counsel. 
Telephone: 202-366-2992; Email: [email protected]. You may send mail 
to these officials at: National Highway Traffic Safety Administration, 
1200 New Jersey Avenue SE, Washington, DC 20590.

SUPPLEMENTARY INFORMATION: 

Table of Contents

I. Executive Summary
II. Background and Safety Need
III. NHTSA's Statutory Authority
IV. ADB Rulemaking Mandate in the Infrastructure, Investment and 
Jobs Act
V. Summary of the NPRM
VI. Overview of Comments
VII. NHTSA Research and Testing
VIII. Final Rule and Response to Comments
    A. Summary of the Final Rule and Modifications to the NPRM
    B. Interpretation of FMVSS No. 108 as Applied to ADB Systems
    C. Track Testing Requirements and Procedures
    1. Practicability of Proposed Test Scenarios
    2. Test Fixtures vs. Stimulus Vehicles
    3. Justification for Testing on Curves and General Approach for 
Scenario Selection
    4. Maximum Illuminance Criteria (Glare Limits)
    5. ADB Adaptation Time
    6. Test Fixture Specifications
    7. Test Fixture Placement
    8. Test Scenarios
    a. Scenario 1: Oncoming Straight
    b. Scenario 2: Oncoming Small Left Curve
    c. Scenario 3: Oncoming Medium Left Curve
    d. Scenario 4: Oncoming Large Left Curve
    e. Scenario 5: Oncoming Medium Right Curve
    f. Scenario 6: Oncoming Large Right Curve
    g. Scenario 7: Preceding Straight
    h. Scenario 8: Preceding Medium Left Curve
    i. Decision Not To Include Oncoming Short Right Curve Scenario
    9. Other Test Parameters and Conditions
    a. Radius of Curvature
    b. Test Vehicle Speed and Acceleration
    c. Headlamp Aim
    d. Road Surface
    e. Ambient and Reflected Light
    f. Superelevation
    g. Lane Divisions
    h. Hills
    10. Data Acquisition and Measurement
    a. Photometers
    b. Sampling Rate
    c. Noise and Filtering
    d. Allowance for Momentary Glare Exceedances
    e. Vehicle Pitch
    11. Repeatability
    D. Laboratory (Component-Level) Testing
    1. Need for Laboratory Testing
    2. Definitions of Areas of Reduced and Unreduced Intensity
    3. Requirements for Area of Reduced Intensity
    4. Requirements for Area of Unreduced Intensity
    5. Transition Zone
    6. Veiling Glare
    E. Minimum Activation Speed
    F. Operator Controls, Indicators, Malfunction Detection, and 
Operating Instructions
    G. Accommodation of Different Technologies
    H. Requirements for Semiautomatic Beam Switching Devices Other 
Than ADB and Applicability of Compliance Options
    I. Physical Test Requirements
    J. Other Requirements
    K. Information Reporting
    L. Aftermarket Compliance
    M. Exemption Petitions
    N. Compliance Date
    O. Regulatory Alternatives
    P. Overview of Benefits and Costs
IX. Appendix to FMVSS No. 108 (Table of Contents)
X. Rulemaking Analyses and Notices
Appendix A. Comparison of Oncoming Glare Limits to Table XIX Right-
Side Photometric Maxima
Appendix B. Example of Laboratory Photometric Testing of Adaptive 
Driving Beam
Appendix C. ADB Performance With Motorcycle Test Fixture
Appendix D. List of Comments Cited in Preamble

I. Executive Summary

    This final rule amends Federal Motor Vehicle Safety Standard (FMVSS 
or Standard) No. 108, ``Lamps, reflective devices, and associated 
equipment,'' to enable the certification of adaptive driving beam (ADB) 
headlighting systems on vehicles sold in the United States. NHTSA is 
issuing this final rule under the National Traffic and Motor Vehicle 
Safety Act (Safety Act), 49 U.S.C. Chapter 301, Motor Vehicle Safety 
(49 U.S.C. 30101 et seq.).

Glare, Visibility, and Adaptive Driving Beam Technology

    Adaptive driving beam headlamps utilize technology that actively 
modifies the headlamp beams to provide more illumination while not 
glaring other vehicles. The requirements adopted today are intended to 
amend FMVSS No. 108 to permit this technology and ensure that it 
operates safely.
    Vehicle headlamps must satisfy two different safety needs: 
Visibility and glare prevention. The primary function of headlamps is 
to provide forward visibility for drivers. At the same time, there is a 
risk that intense headlamp illumination may be directed towards 
oncoming or preceding vehicles. Such illumination, referred to as 
glare, can reduce the ability of other drivers to see and can cause 
discomfort. Headlighting has therefore traditionally entailed a 
tradeoff between long-distance visibility and glare prevention. This is 
reflected in Standard No. 108's requirement that

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headlighting systems have both upper and lower beams. The existing 
headlamp requirements regulate the beam pattern (photometry) of the 
upper and lower beams; they ensure sufficient visibility by specifying 
minimum amounts of light in certain areas on and around the road, and 
prevent glare by specifying maximum amounts of light in directions that 
correspond to where oncoming and preceding vehicles would be.
    ADB systems are an advanced type of headlamp technology that 
optimizes beam patterns without driver action. Semiautomatic beam 
switching technology was first introduced on vehicles in the United 
States in the 1950s and has become increasingly popular in the last few 
decades. The semiautomatic beam switching technology currently 
available in the United States (commonly referred to as ``auto hi-
beam'' or ``high beam assist'') automatically switches between the 
lower and upper beams. This provides safety benefits because research 
has shown that most drivers underutilize the upper beams, and 
semiautomatic beam switching facilitates increased upper beam use in 
situations where drivers of other vehicles will not be glared.
    ADB systems are an improvement over ``auto hi-beam'' technology 
currently available in the United States because they are capable of 
providing more illumination than a lower beam without increasing glare. 
When operating in automatic mode, instead of simply switching between 
the upper and lower beams, an ADB system is able to provide a dynamic, 
adaptive beam pattern that changes based on the presence of other 
vehicles or objects, providing less illumination to occupied areas of 
the road and more illumination to unoccupied areas of the road. ADB 
systems can therefore provide more illumination than existing lower 
beams without glaring other motorists (if operating correctly). ADB 
systems achieve this enhanced performance by utilizing advanced 
sensors, data processing software, and headlamp hardware.
    ADB systems are available in foreign markets but are not currently 
offered on vehicles in the United States. This final rule amends FMVSS 
No. 108 to permit ADB systems on vehicles in the United States and 
ensure that they operate safely. ADB, like other headlamp technologies, 
implicates the twin safety needs of visibility and glare prevention. 
This final rule does three main things that, taken together, allow ADB 
systems and ensure that they meet these safety needs.
    First, it amends FMVSS No. 108 to allow ADB systems. It amends, 
among other things, the existing headlamp requirements so that ADB 
technology is permitted.
    Second, this final rule adopts requirements to ensure that ADB 
systems do not increase glare to other motorists beyond current lower 
beams. ADB systems are capable of providing a variable, adaptive beam 
in the presence of other vehicles that provides more illumination than 
the currently allowed lower beam. However, if ADB systems do not 
accurately detect other vehicles on the road and shade them 
accordingly, other motorists will be glared.\1\ The rule addresses this 
safety need by including vehicle-level track-test requirements 
specifically tailored to evaluate whether an ADB system functions 
safely and limits glare for other motorists.
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    \1\ NHTSA is sensitive to concerns about glare due to the 
numerous complaints from the public it has received and its own 
research (prompted, in part, by these complaints and a 2005 
Congressional mandate to study the risks from glare).
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    Third, it adopts component-level laboratory-tested requirements 
related to both glare and visibility, as well as a limited set of other 
system requirements, such as requirements for manual override and fail-
safe operation.
    In drafting this final rule, NHTSA considered two major regulatory 
alternatives. One was the Economic Commission for Europe (ECE) 
regulations that apply to ADB systems, including a vehicle-level test 
on public roads. However, the ECE road test is not appropriate for 
adoption as an FMVSS because it does not provide sufficiently objective 
performance criteria. We also considered a Society for Automotive 
Engineers (SAE) recommended practice, J3069 JUN2016, Surface Vehicle 
Recommended Practice; Adaptive Driving Beam, as well as the updated 
version of this practice (published in March 2021). The final rule 
follows SAE J3069 in many significant respects, but also differs from 
it in significant ways.
    NHTSA published the notice of proposed rulemaking (NPRM) preceding 
this final rule on October 12, 2018 (83 FR 51766). Many industry 
comments to the NPRM urged closer harmonization with SAE J3069. These 
comments focused primarily on costs from dis-harmonization due to the 
resulting need for market-specific hardware and components. In response 
to the comments, NHTSA conducted additional vehicle-level testing to 
validate modifications to the proposal to harmonize more closely with 
SAE J3069 while still retaining sufficient realism. As a result, NHTSA 
has changed some aspects of the proposal. The final rule more closely 
conforms to SAE J3069 in a number of respects but continues to deviate 
from it for reasons discussed in detail in this preamble.

Differences Between This Final Rule and the Proposal

    The following discussion highlights the more noteworthy differences 
between the final rule and the NPRM. All changes from the proposal are 
discussed in the appropriate sections of this preamble.

Vehicle-Level Track Test To Evaluate Glare

    Stimulus test fixtures instead of stimulus vehicles. The final rule 
specifies test fixtures instead of stimulus vehicles. This change will 
result in a less complex test that is more closely harmonized with SAE 
J3069, while still ensuring that ADB systems operate safely. While the 
test fixture specifications follow SAE J3069 with respect to the 
locations of the photometers and stimulus lamps, the final rule 
requires the use of more real-world representative lighting in the 
compliance test by specifying original equipment vehicle headlamps and 
taillamps.
    More efficient test scenarios. The final rule simplifies the number 
and complexity of test scenarios. The final rule continues to differ 
from SAE J3069 by specifying test scenarios with actual curves because 
this is necessary to evaluate how an ADB system would perform in the 
real world. We have, however, modified many of the curved-path test 
scenarios. NHTSA believes that the final scenarios meet the need for 
motor vehicle safety by containing a broad range of realistic road 
geometries and vehicle interactions.
    Data measurement and allowances. The final rule changes how NHTSA 
will measure and evaluate ADB system illuminance. This includes an 
added specification for a data filter and replacing the proposed 
International Roughness Index parameter with an explicit adjustment for 
vehicle pitch.

Component-Level Laboratory Photometric Testing

    The final rule retains, in modified form, the proposed requirements 
for component-level laboratory testing.
    Defining ``adaptive driving beam'' as a new beam type. The final 
rule defines a new beam type, ``adaptive driving beam.'' The final rule 
also provides manufacturers flexibility to determine when to provide an 
area of reduced or unreduced intensity (subject to several requirements 
or constraints, such as the

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track test that evaluates glare). This will enable systems to provide 
an area of reduced intensity not only to prevent glare to oncoming or 
preceding vehicles, but also in other situations in which reduced 
intensity would be beneficial.
    Requirements for areas of reduced intensity. The final rule follows 
the NPRM and specifies the existing lower beam photometric test points 
(both minima and maxima). The minima are important because the final 
rule does not include any ``false positive'' tests to ensure that an 
ADB system does not mistakenly dim the beam in the absence of other 
vehicles, and the maxima are necessary to help ensure that other 
motorists are not subject to glare beyond that experienced with lower 
beams.
    Requirements for areas of unreduced intensity. The final rule 
follows the NPRM and specifies the existing upper beam photometric test 
points (both minima and maxima). Requiring a minimum level of 
illumination is important to ensure a minimum level of visibility. The 
final rule does not adopt the higher ECE upper beam maxima.
    Transition zone. The final rule allows for a 1-degree transition 
zone between an area of reduced intensity and an area of unreduced 
intensity. The lower and upper beam photometric test points will not 
apply within a transition zone (except for the upper beam maximum at H-
V, which still applies). Manufacturers essentially will be free to 
determine the areas of reduced and unreduced intensity and, therefore, 
the boundaries of the transition zone.

Other System Requirements

    The final rule retains many of the proposed system requirements. 
However, the minimum activation speed has been decreased from 25 mph to 
20 mph to give greater flexibility to manufacturers wishing to provide 
for hysteresis in the system design. The final rule also exempts ADB 
systems from many of the vehicle headlamp aiming device requirements, 
which would add unnecessary costs to ADB systems.
Benefits and Costs
    This final rule is not significant and so was not reviewed by OMB 
under E.O. 12866. NHTSA has determined that quantifying the benefits 
and costs is not practicable in this rulemaking because of limitations 
on the agency's ability to accurately estimate the target population 
and the effectiveness of ADB. We have, however, identified the problem 
this rule is intended to address, considered whether existing 
regulations have contributed to the problem, qualitatively assessed the 
costs and benefits, and considered alternatives. This final rule 
appropriately balances the needs for visibility and glare prevention, 
and adopts requirements that are both practicable and sufficient to 
assess whether an ADB system operates safely. This final rule does not 
require manufacturers to provide ADB systems, but only specifies the 
requirements the systems must meet if equipped on vehicles.

II. Background and Safety Need

    On October 12, 2018, NHTSA published the NPRM (83 FR 51766) 
underlying this final rule. NHTSA is publishing this final rule to set 
forth the amendments to FMVSS No. 108 (49 CFR 571.108), summarize the 
comments received in response to the proposal, and provide the agency's 
responses to those comments.
    This section provides a brief introduction to the safety needs 
addressed in this rulemaking, ADB technology, the relevant industry and 
international standards for ADB systems, the petition for rulemaking 
that prompted the NPRM, and related exemption petitions and NTSB 
recommendations. For additional detailed background information 
(including an explanation of the headlamp photometric requirements and 
regulatory history and research efforts related to glare), the reader 
is referred to the NPRM.\2\
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    \2\ See pp. 51768-51774.
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Safety Needs: Visibility and Glare Prevention

    Vehicle headlamps primarily satisfy two safety needs: Visibility 
and glare prevention. Headlamps illuminate the area ahead of the 
vehicle and provide forward visibility.\3\ Headlamp illumination, 
however, has the potential to glare other motorists. Accordingly, 
headlighting systems have traditionally consisted of lower beams and 
upper beams. The lower beams (also referred to as passing beams or 
dipped beams) are designed to provide relatively high levels of light 
in the close-in forward visibility region, and to provide reduced light 
intensity in longer-distance regions, where oncoming or preceding 
vehicles would be glared. The lower beams are intended for use during 
lower-speed driving or when meeting or closely following another 
vehicle. Upper beams (also referred to as high beams, main beams, or 
driving beams) are designed to provide relatively high levels of 
illumination in both close-in and longer distance regions. They are 
intended primarily for distance illumination and for use when not 
meeting or closely following another vehicle. (FMVSS No. 108 
establishes maximum levels of intensity the upper beam may not exceed.)
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    \3\ They also make the vehicle more visible to other road users.
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    Visibility and glare are both related to motor vehicle safety. 
Visibility has an obvious, intuitive relation to safety: The better 
drivers can see the road, the better they can react to road conditions 
and obstacles to avoid crashes. Although the qualitative connection to 
safety is intuitive, quantifying the effect of visibility on crash risk 
is difficult because of many confounding factors (for example, was a 
late-night crash caused by diminished visibility or driver fatigue?). 
Still, evidence suggests that diminished visibility likely increases 
the risk of crashes, particularly crashes at higher speeds involving 
pedestrians, animals, trains, and parked cars.\4\ The NPRM (in Appendix 
A) included an analysis estimating the target population that could 
benefit from the increased visibility provided by ADB systems.
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    \4\ Nighttime Glare and Driving Performance, Report to Congress 
(2007), National Highway Traffic Safety Administration, Department 
of Transportation [hereinafter ``2007 Report to Congress''], p. 6. A 
2016 study by the Insurance Institute for Highway Safety noted that 
``[t]wenty-nine percent of all fatalities during 2014 occurred in 
the dark on unlit roads. Although factors such as alcohol impairment 
and fatigue contributed to many of these crashes, poor visibility 
likely also played a role.'' Ian J. Reagan, Matthew L. Brumbelow & 
Michael J. Flannagan. 2016. The Effects of Rurality, Proximity of 
Other Traffic, and Roadway Curvature on High Beam Headlamp Use 
Rates. Insurance Institute for Highway Safety, pp. 2-3 (citations 
omitted). See also Michael J. Flannagan & John M. Sullivan. 2011. 
Feasibility of New Approaches for the Regulation of Motor Vehicle 
Lighting Performance. Washington, DC: National Highway Traffic 
Safety Administration, p. 5 (NHTSA-2018-0090-0002) (``The conclusion 
of our analysis was that pedestrian crashes were by far the most 
prevalent type of crash that could in principle be addressed by 
headlighting.'').
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    Glare is related to safety because it can degrade important aspects 
of driving performance. Glare is a sensation caused by bright light in 
an observer's field of view. Headlamp illumination can glare drivers of 
oncoming or preceding vehicles (via the rearview or side mirrors). 
Empirical evidence suggests that headlamp glare decreases visibility 
distance, increases reaction time, and reduces detection probability, 
among other things.\5\ It can

[[Page 9919]]

also cause discomfort. Despite this evidence, it remains difficult to 
quantify the effect of glare on crash risk. Unlike drug or alcohol use, 
there is usually no way to determine precisely the amount of glare that 
was present in a given crash. Nevertheless, some police crash reports 
mention glare as a potential cause, and it is reasonable to expect that 
glare can reduce visibility, and reductions in visibility caused by 
headlamp glare increase crash risk.\6\ Discomfort attributable to glare 
might also indirectly affect crash risk (for example, if a driver 
reacts to glare by changing their direction of gaze).\7\ In addition, 
discomfort caused by glare may induce some drivers, particularly older 
drivers, to avoid driving at night or simply increase their 
annoyance.\8\
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    \5\ 2007 Report to Congress, pp. iv, 11-14. See also, e.g., John 
D. Bullough et al. 2003. An Investigation of Headlamp Glare: 
Intensity, Spectrum and Size, DOT HS 809 672. Washington, DC: U.S. 
Department of Transportation, National Highway Traffic Safety 
Administration [hereinafter ``Investigation of Headlamp Glare''], p. 
1. (``It is almost always the case that headlamp glare reduces 
visual performance under driving conditions relative to the level of 
performance achievable without glare.'')
    \6\ John D. Bullough et al. 2008. Nighttime Glare and Driving 
Performance: Research Findings, DOT HS 811 043. Washington, DC: U.S. 
Department of Transportation, National Highway Traffic Safety 
Administration, p. I-4.
    \7\ Id., p. 33. But see Investigation of Headlamp Glare, p. 3 
(``Very few studies have probed the interactions between discomfort 
and disability glare, or indeed any driving-performance related 
factors . . . .'').
    \8\ 2007 Report to Congress, p. iv.
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    The potential problems associated with glare are highlighted by the 
thousands of complaints NHTSA has received from the public on the 
issue, as well as congressional interest. The introduction of halogen 
headlamp technology in the late 1970s and high-intensity discharge and 
auxiliary headlamps in the 1990s was accompanied by a marked upswing in 
the number of glare complaints to NHTSA. In response to increased 
consumer complaints in the late 1990s, NHTSA published a Request for 
Comments in 2001 on issues related to glare from headlamps, fog lamps, 
driving lamps, and auxiliary headlamps.\9\ NHTSA received more than 
5,000 comments, most of which concerned nighttime glare from front-
mounted lamps.\10\ In 2005 Congress directed DOT to study the risks of 
glare.\11\ NHTSA subsequently initiated a multipronged research program 
to examine the causes of, and possible solutions to, glare.\12\
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    \9\ 66 FR 49594 (Sept. 28, 2001).
    \10\ 69 FR 54255 (Sept. 8, 2004).
    \11\ Safe, Accountable, Flexible, Efficient Transportation 
Equity Act: A Legacy for Users, Public Law 109-59, Sec. 2015 (2005).
    \12\ For more information, see the NPRM at p. 51771.
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Adaptive Driving Beam Technology

    ADB systems are an advanced type of headlamp technology that 
optimizes beam patterns without driver action. Semiautomatic beam 
switching technology was first introduced on vehicles in the United 
States in the 1950s and has become increasingly popular in the last few 
decades with the wider deployment of camera-based driver assistance 
technologies. The semiautomatic beam switching technology currently 
available on vehicles in the United States is commonly referred to as 
``auto hi-beam'' or ``high beam assist,'' among other terms. This 
currently-available technology automatically switches between the lower 
and upper beams (while still allowing the driver to manually switch 
beams).\13\ Semiautomatic beam switching enhances safety because it 
facilitates increased use of the upper beams in situations where 
drivers of other vehicles will not be glared. Research has shown that 
most drivers under-utilize the upper beams,\14\ despite the fact that 
``driving with lower-beam headlamps can result in insufficient 
visibility for a number of driving situations,'' \15\ particularly at 
higher speeds.\16\
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    \13\ Under FMVSS No. 108 this technology is classified as a 
``semiautomatic beam switching device'' because it provides either 
automatic or manual control of switching between the lower and upper 
beams at the option of the driver. See S4 (definition of 
``semiautomatic headlamp beam switching device'') and S9.4.
    \14\ See, e.g., John D. Bullough, Nicholas P. Skinner, Yukio 
Akashi, & John Van Derlofske. 2008. Investigation of Safety-Based 
Advanced Forward-Lighting Concepts to Reduce Glare, DOT HS 811 033. 
Washington, DC: National Highway Traffic Safety Administration, p. 
63. (finding that ``abundant evidence suggests that most drivers use 
lower beams primarily, if not exclusively.'') See also, e.g., Mary 
Lynn Mefford, Michael J. Flannagan & Scott E. Bogard. 2006. Real-
World Use of High-Beam Headlamps, UMTRI-2006-11. University of 
Michigan, Transportation Research Institute, p. 6 (finding that 
``high-beam headlamp use is low . . . consistent with previous 
studies that used different methods'').
    \15\ Investigation of Safety-Based Advanced Forward-Lighting 
Concepts to Reduce Glare (DOT HS 811 033), p. 63.
    \16\ Michael J. Flannagan & John M. Sullivan. 2011. Preliminary 
Assessment of The Potential Benefits of Adaptive Driving Beams, 
UMTRI-2011-37. University of Michigan, Transportation Research 
Institute, p. 2.
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    ADB systems are an improvement over the ``auto hi-beam'' technology 
currently available in the United States because they are capable of 
providing more illumination than a lower beam without increasing glare. 
When operating in automatic mode, instead of simply switching between 
the upper and lower beams, the ADB system is able to provide a dynamic, 
adaptive beam pattern that changes based on the presence of other 
vehicles or objects, providing less illumination to occupied areas of 
the road and more illumination to unoccupied areas of the road.\17\ The 
portions of the adaptive beam directed to areas of the roadway occupied 
by other vehicles are at or (for some systems deployed in Europe) even 
below levels of a lower beam.\18\ The portions of the adaptive beam 
directed at unoccupied areas of the road are typically equivalent to an 
upper beam. When the roadway ahead is fully occupied by oncoming or 
preceding vehicles, the adaptive beam is essentially a lower beam. When 
there are no oncoming or preceding vehicles, the adaptive beam is 
essentially an upper beam.\19\
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    \17\ When operating in manual mode--which the driver may obtain 
at any time--the driver is able to switch between the lower and 
upper beams.
    \18\ SAE J3069 JUN 2016, pp. 1-2.
    \19\ There are, however, situations in which it may be 
appropriate to provide less than a full upper beam even in the 
absence of oncoming or preceding vehicles. For example, it may be 
optimal to direct less light at a retroreflective sign or wet 
roadway, in order to minimize glare to the driver of the ADB-
equipped vehicle from reflected light. This is discussed in more 
detail in Section VIII.D.2.
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    So, for example, when an ADB-equipped vehicle (operating in 
automatic mode) travelling on an otherwise unoccupied roadway 
encounters an oncoming vehicle, it switches from an upper beam 
providing high light levels in both close-in and longer distance 
regions to an adaptive beam providing reduced intensity (similar to a 
lower beam) near the oncoming vehicle and unreduced intensity (similar 
to an upper beam) elsewhere. Because the system is able to provide 
unreduced intensity to unoccupied areas of the roadway, while at the 
same time providing reduced intensity to areas near other vehicles, it 
provides more illumination than a conventional lower beam would 
provide. ADB therefore has the potential to reduce the risk of crashes 
by increasing visibility without increasing glare. The adaptive beam is 
particularly useful for distance illumination of pedestrians, animals, 
and objects in or near the road when other vehicles are present and 
thus preclude use of the upper beam.
    ADB systems achieve this enhanced performance by utilizing advanced 
sensors, data processing software, and headlamp hardware (such as 
shutters or LED arrays). Many current ADB systems utilize a camera with 
a typical field of view of approximately 25 degrees left and right to 
detect objects.\20\ High-resolution ADB systems are capable of 
classifying objects and placing optimized levels of light on all 
objects in the driver's view (such as

[[Page 9920]]

retroreflective signs or pedestrians). ADB systems typically use the 
existing headlamps that are modified either with a mechanical shade 
that blocks part of the beam, or (for light-emitting diode [LED] 
headlamps) extinguish individual LEDs. The ADB systems NHTSA tested 
required the driver to select the ADB mode using the headlighting 
system control. Once in ADB mode, the systems were designed to activate 
the adaptive beam at speeds between 20 mph and 40 mph and deactivate 
the adaptive beam (and provide a lower beam) from 15 mph to 25 mph.
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    \20\ SAE comment (NHTSA-2018-0090-0167), p. 9 (``The forward 
camera vision on today's vehicles only extends to approximately 25 
degrees left and right[.]''). We assume this is the camera's field 
of view for the illustrative examples in the discussions of the 
curve scenarios.
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European ADB Requirements

    ADB was first permitted in Europe by amendments to ECE Regulation 
No. 48 in 2006.\21\ ECE regulations allow ADB systems under the 
umbrella of adaptive front lighting systems (AFS). There are a variety 
of requirements for AFS generally and adaptive lighting in particular. 
Unlike the FMVSS, which rely on manufacturer self-certification, ECE 
requirements for ADB systems utilize the type approval framework used 
throughout the ECE standards. Under the type approval framework, 
production samples of new model cars must be approved by regulators 
before being offered for sale. This approval is based, in part, on 
testing whole vehicles on public roadways to verify performance. The 
ECE requirements specify that the adaptation of the main-beam not cause 
any discomfort, distraction or glare to the driver of the ADB-equipped 
vehicle (for example, glare to the driver cause by excessive 
illumination of retroreflective signs) or to oncoming and preceding 
vehicles. This is demonstrated through the technical service performing 
a test drive on various types of roads (e.g., urban, multi-lane roads, 
and country roads), at a variety of speeds, and in a variety of 
specified traffic conditions. The performance of the ADB system is 
evaluated based on the subjective observations of the type approval 
engineer during this test drive. The ECE road test is therefore not 
appropriate for adoption as an FMVSS because it does not provide 
objective performance criteria. However, the proposed track test 
scenarios were based, in part, on the ECE road-test scenarios.
---------------------------------------------------------------------------

    \21\ Uniform provisions concerning the approval of vehicles with 
regard to the installation of lighting and light-signalling devices 
(R48) and Regulation No. 123, Uniform provisions concerning the 
approval of adaptive front-lighting systems (AFS) for motor vehicles 
(R123) of the Economic Commission for Europe (ECE).
---------------------------------------------------------------------------

SAE J3069

    In June 2016, SAE International (SAE) published SAE J3069 JUN2016, 
Surface Vehicle Recommended Practice; Adaptive Driving Beam (SAE 
J3069).\22\ The recommended practice, which is based, in part, on 
NHTSA's research (described in Section VII below), includes (among 
other requirements) a track test to evaluate ADB system performance in 
avoiding excessive glare to other vehicles. It specifies a straight 
test path with a single lane, on either side of which it specifies the 
placement of test fixtures simulating an opposing or preceding vehicle. 
See Figure 1. The test fixtures are fitted with lamps having a 
specified luminous intensity, color, and size intended to simulate the 
taillamps and headlamps on a typical car, truck, or motorcycle. Four 
different test fixtures are specified: An opposing (i.e., oncoming) 
car/truck; an opposing motorcycle; a preceding car/truck; and a 
preceding motorcycle. In addition to simulated vehicle lighting, the 
test fixtures are fitted with photometers \23\ to measure the 
illumination from the ADB headlamps. Although the test does not specify 
any scenarios with a curved test path, the placement of the fixtures 
relative to the straight test path, along with a sudden appearance 
test, are intended to simulate curves.
---------------------------------------------------------------------------

    \22\ SAE has recently published a revised version of this 
recommended practice (SAE J3069 MAR2021). These limited revisions, 
where potentially relevant to this final rule, are identified and 
discussed in subsequent sections of this preamble.
    \23\ A photometer, or illuminance meter, is an instrument that 
measures light.
[GRAPHIC] [TIFF OMITTED] TR22FE22.001

    SAE J3069 sets out a total of 18 different test drive scenarios. 
The scenarios vary the test fixture, the placement of the fixture, and 
whether the lamps on the test fixture are illuminated for the entire 
test drive, or are instead suddenly illuminated when the ADB vehicle 
reaches a specified distance from the test fixture. During each of 
these test drives, the illuminance \24\ recorded at 30 meters (m), 60 
m, 120 m, and 155 m must not exceed the maximum allowed illuminance 
specified for each distance. See Table 1. These illuminance maxima are 
based on and similar (but not identical) to the maximum illuminance 
limits developed in NHTSA's published research and proposed in the 
NPRM. If there is no recorded illuminance value at any of these 
distances, interpolation is used to estimate the illuminance at that 
distance. For sudden appearance tests, the system is given a maximum of 
2.5 seconds to react and adjust the beam to reduce illumination to a 
level within the applicable maximum. If any recorded (or interpolated) 
illuminance value exceeds the applicable maximum illuminance, SAE J3069 
provides for an

[[Page 9921]]

allowance: The same test drive scenario is run with the lower beam 
activated. The ADB system can still be deemed to have passed the test 
if any of the ADB exceedances do not exceed 125% of the measured (or 
interpolated) illuminance value(s) for the lower beam.
---------------------------------------------------------------------------

    \24\ Illuminance is the amount of light falling on a surface. 
The unit of measurement for illuminance is lux.

             Table 1--SAE J3069 Maximum Allowed Illuminance
------------------------------------------------------------------------
                                              Maximum         Maximum
                                           illuminance,    illuminance,
 Range from headlamp to  photometer  (m)     oncoming        preceding
                                               (lux)           (lux)
------------------------------------------------------------------------
30......................................             1.8            18.9
60......................................             0.7             8.9
120.....................................             0.3             4.0
155.....................................             0.3             4.0
------------------------------------------------------------------------

    In addition to the dynamic track test, SAE J3069 contains a number 
of other system requirements, such as a physical test (e.g., a 
corrosion test) and telltale requirements. It also requires the system 
to comply with a limited set of component-level laboratory-based 
photometry requirements. For example, for the portion of the adaptive 
beam that is directed at areas of the roadway unoccupied by other 
vehicles, the lower beam minimum values specified in the relevant SAE 
standard must be met.\25\ Specific provisions of SAE J3069 are 
discussed in more detail in the responses to the comments.
---------------------------------------------------------------------------

    \25\ As explained in the NPRM, FMVSS No. 108 also contains 
laboratory-based photometric requirements. SAE J3069 refers not to 
these requirements, but to analogous requirements specified in other 
SAE standards.
---------------------------------------------------------------------------

Toyota Petition for Rulemaking, ADB Exemption Petitions, and NTSB 
Recommendation

    While ADB systems have been available in Europe for a number of 
years, they have not yet been deployed in the United States, largely 
because of industry uncertainty about whether FMVSS No. 108 allows ADB 
systems.\26\ Prior to the NPRM, NHTSA had not formally addressed 
whether the lighting standard allows ADB systems. Accordingly, in 2013, 
Toyota Motor North America, Inc. (Toyota) petitioned NHTSA for 
rulemaking to amend FMVSS No. 108 to give manufacturers the option of 
equipping vehicles with ADB systems.\27\ In its petition, Toyota 
described how its system works, identified potential safety benefits of 
the system, and discussed its view of how ADB should be treated under 
the agency's regulations. NHTSA granted Toyota's petition and the NPRM 
was NHTSA's action on that grant.
---------------------------------------------------------------------------

    \26\ See, e.g., SAE J3069 (``However, in the United States it is 
unclear how ADB would be treated under the current Federal Motor 
Vehicle Safety Standard (FMVSS) 108.'').
    \27\ Letter from Tom Stricker, Toyota Motor North America, Inc. 
to NHTSA (Mar. 29, 2013). Toyota requested confidential treatment 
for portions of its submission. A redacted copy of the petition has 
been placed in the docket for this rulemaking.
---------------------------------------------------------------------------

    After receiving Toyota's petition, but prior to the NPRM, NHTSA 
received two exemption petitions (under 49 CFR part 555) for ADB-
equipped vehicles. In 2016, Volkswagen Group of America (Volkswagen) 
submitted a petition for a temporary exemption from some of the 
requirements of FMVSS No. 108 to sell a limited number of ADB-equipped 
vehicles. NHTSA published a notice of receipt of this petition on 
September 11, 2017, and provided a 30-day comment period.\28\ BMW of 
North America, LLC (BMW) subsequently submitted a similar petition, 
dated October 27, 2017. On March 22, 2018, NHTSA published a notice of 
receipt of the BMW petition and requested additional information from 
both petitioners.\29\ Both Volkswagen and BMW subsequently submitted 
additional information to the docket. Prior to today, NHTSA has not 
made a decision on either petition; as we explain later in the 
preamble, NHTSA is denying the petitions in a separate notice published 
today.
---------------------------------------------------------------------------

    \28\ 82 FR 42720 (Docket No. NHTSA-2017-0018).
    \29\ 83 FR 12650 (Docket No. NHTSA-2017-0018).
---------------------------------------------------------------------------

    Shortly before the NPRM was published in October 2018, the National 
Transportation Safety Board (NTSB) published a special investigation 
report that examined pedestrian crashes and related phenomena.\30\ The 
report covered, among other things, vehicle headlighting system 
performance. The NTSB found that the FMVSS should not limit advanced 
vehicle lighting systems that have been shown to have safety benefits. 
It also found that vehicle headlighting systems require an evaluation 
that is more advanced than laboratory bench-testing. The report went on 
to recommend that NHTSA revise FMVSS No. 108 to allow adaptive 
headlight systems. This final rule responds to these NTSB 
recommendations.
---------------------------------------------------------------------------

    \30\ National Transportation Safety Board. 2018. Pedestrian 
Safety. Special Investigation Report NTSB/SIR-18/03. Washington, DC.
---------------------------------------------------------------------------

III. NHTSA's Statutory Authority

    NHTSA is issuing this final rule under the Motor Vehicle Safety Act 
(Safety Act), 49 U.S.C. Chapter 301, Motor Vehicle Safety (49 U.S.C. 
30101 et seq.). Under the Safety Act, the Secretary of Transportation 
is responsible for prescribing motor vehicle safety standards that are 
practicable, meet the need for motor vehicle safety, and are stated in 
objective terms.\31\ ``Motor vehicle safety'' is defined in the Safety 
Act as ``the performance of a motor vehicle or motor vehicle equipment 
in a way that protects the public against unreasonable risk of 
accidents occurring because of the design, construction, or performance 
of a motor vehicle, and against unreasonable risk of death or injury in 
an accident, and includes nonoperational safety of a motor vehicle.'' 
\32\ ``Motor vehicle safety standard'' means a minimum performance 
standard for motor vehicles or motor vehicle equipment.\33\ When 
prescribing such standards, the Secretary must consider all relevant, 
available motor vehicle safety information.\34\ The Secretary must also 
consider whether a proposed standard is reasonable, practicable, and 
appropriate for the types of motor vehicles or motor vehicle equipment 
for which it is prescribed and the extent to which the standard will 
further the statutory purpose of reducing traffic accidents and 
associated deaths.\35\ The responsibility for promulgation of Federal 
Motor Vehicle Safety Standards is delegated to NHTSA.\36\ The agency 
carefully considered these statutory requirements in developing this 
final rule. We evaluate this rule with respect to these requirements in 
subsequent sections of this preamble.
---------------------------------------------------------------------------

    \31\ 49 U.S.C. 30111(a).
    \32\ 49 U.S.C. 30102(a)(9).
    \33\ 30102(a)(10).
    \34\ 30111(b)(1).
    \35\ 30111(b)(3)-(4).
    \36\ See 49 CFR 1.95.
---------------------------------------------------------------------------

IV. ADB Rulemaking Mandate in the Infrastructure, Investment and Jobs 
Act

    Congress has recently passed, and the President has signed, the 
Infrastructure, Investment and Jobs Act (``IIJA'').\37\ Section 24212 
of IIJA contains a mandate for a variety of headlamp rulemakings, 
including an ADB rulemaking. Specifically, IIJA requires in paragraph 
(b) of Sec.  24212 that ``[n]ot later than 2 years after the date of 
enactment of this Act, the Secretary shall issue a final rule amending 
Standard 108'' to, among other things, ``allow for the use on vehicles 
of adaptive driving beam headlamp systems.'' Paragraph (a) of Sec.  
24212 defines ``adaptive driving beam headlamp'' to mean a headlamp 
``that meets the performance requirements specified in SAE 
International Standard J3069, published on June 30, 2016.'' Paragraph 
(c) of Sec.  24212 states that ``[n]othing in this section precludes 
the

[[Page 9922]]

Secretary from--. . . (2) revising Standard 108 to reflect an updated 
version of SAE International Standard J3069, as the Secretary 
determines to be--(A) appropriate; and (B) in accordance with section 
30111 of [the Safety Act].'' Today's final rule satisfies both that ADB 
mandate and the core Safety Act requirement that FMVSSs, among other 
things, ``meet the need for motor vehicle safety,'' \38\ which, as 
explained throughout this notice, would not be met by a standard that 
solely codified SAE J3069.
---------------------------------------------------------------------------

    \37\ H.R. 3684 (117th Congress) (2021).
    \38\ 49 U.S.C. 30111(a).
---------------------------------------------------------------------------

    Paragraphs (a) and (b) of Sec.  24212, taken together, instruct 
NHTSA to amend FMVSS No. 108 to allow ADB systems that at least meet 
the requirements of SAE J3069. Paragraph (b) instructs NHTSA to 
``amend[ ] Standard 108.'' Standard 108 is an FMVSS, and FMVSSs are 
subject to the criteria in Sec.  30111 of the Safety Act, which 
include, importantly, meeting the need for motor vehicle safety. The 
directive to ``amend[ ] Standard 108'' in paragraph (b) would conflict 
with the specification of SAE J3069 in paragraph (a) if SAE J3069 did 
not meet the need for safety and NHTSA were limited to allowing any 
systems that met that standard. We also do not believe Sec.  24212 
means that Congress determined that SAE J3069 satisfies Sec.  30111, as 
the codified text does not express this conclusion nor is there such a 
finding elsewhere in the IIJA statute or legislative history. 
Therefore, reading paragraphs (a) and (b) as requiring NHTSA to amend 
FMVSS No. 108 so that ADB systems that meet SAE J3069 can also meet the 
requirements of the revised Standard 108 harmonizes the directive in 
paragraph (b) to ``amend[ ] Standard 108'' with the specification of 
SAE J3069 in paragraph (a). It also harmonizes with the Safety Act, as 
well as with the National Technology Transfer and Advancement Act,\39\ 
which, while generally requiring the use of consensus standards, 
importantly reserves to an agency the ability to decline using a 
consensus standard that it determines does not meet the agency's 
governing statutes.
---------------------------------------------------------------------------

    \39\ Public Law 104-113, 110 Stat. 775 (1996). See Section X, 
Rulemaking Analyses and Notices.
---------------------------------------------------------------------------

    As the Supreme Court has explained, statutes should be construed 
harmoniously, so that ``when two statutes are capable of coexistence,'' 
they should be construed as each having effect.\40\ The interpretation 
taken in this final rule achieves that goal. In contrast, an 
interpretation that would require NHTSA to amend the standard to permit 
any ADB system conforming to SAE J3069 would be an implicit repeal of 
the Safety Act in this instance--and there is a strong presumption 
against implied repeals.\41\ As the Supreme Court has repeatedly 
pointed out, ``repeals by implication are not favored and will not be 
presumed unless the intention of the legislature to repeal is clear and 
manifest.'' \42\ Due to this ``relatively stringent standard,'' implied 
repeals are ``rare,'' \43\ and have generally been limited to 
situations ``where provisions in two statutes are in irreconcilable 
conflict, or where the latter Act covers the whole subject of the 
earlier one and is clearly intended as a substitute.\44\ But ``in 
either case, the intention of the legislature to repeal must be clear 
and manifest.'' \45\ Here, Congress has shown no such manifest 
intention in Sec.  24212. In particular, as NHTSA had already published 
an NPRM tentatively determining that SAE J3069 does not meet the need 
for safety, the Agency expects that a Congressional override of this 
tentative determination would have been far clearer, given NHTSA's 
general authority and role in determining that adequate level of 
safety. Moreover, neither of the two categories of repeal by 
implication apply here because there is a way to harmonize Sec.  24212 
and the Safety Act, and Sec.  24212 does not ``cover the whole subject 
matter'' of the Safety Act and is not clearly intended as a substitute. 
Therefore, we read paragraphs (a) and (b) to permit NHTSA to amend 
FMVSS No. 108 to impose requirements more stringent than SAE J3069 as 
long as those requirements are not inconsistent with SAE J3069.
---------------------------------------------------------------------------

    \40\ J.E.M. AG Supply, Inc. v. Pioneer Hi-Bred Int'l, Inc., 534 
U.S. 124, 143-144 (2001) (``[W]hen two statutes are capable of 
coexistence, it is the duty of the courts, absent a clearly 
expressed congressional intention to the contrary, to regard each as 
effective.'') (quotations and citations omitted).
    \41\ See Norman J. Singer & Shambie Singer, 2B Sutherland 
Statutory Construction Sec.  51:2 (7th ed.) (``Courts assume that a 
legislature always has in mind previous statutes relating to the 
same subject when it enacts a new provision. In the absence of any 
express repeal or amendment, the new provision is presumed to accord 
with the legislative policy embodied in those prior statutes[.]''). 
See also, e.g., U.S. v. City of New York, 359 F.3d 83, 98 (2nd. Cir. 
2004) (``The courts are not at liberty to pick and choose among 
congressional enactments, and when two statutes are capable of co-
existence, it is the duty of the courts, absent a clearly expressed 
congressional intention to the contrary, to regard each as 
effective.'') (citations and quotations omitted).
    \42\ Nat'l Ass'n of Home Builders v. Defenders of Wildlife, 551 
U.S. 644, 662 (2007) (quotations, alterations, and citations 
omitted). See also, e.g., Branch v. Smith, 538 U.S. 254, 273 (2003) 
(``We have repeatedly stated, however, that absent a clearly 
expressed congressional intention, repeals by implication are not 
favored[.]'') (citations and quotations omitted); Athey v. U.S., 123 
Fed. Cl. 42, 52 (2015) (``[T]the law is clear that repeals by 
implication are not favored absent clear congressional intent[.]'') 
(quotations and citations omitted).
    \43\ J.E.M. AG Supply, Inc., 534 U.S. at 142.
    \44\ Branch, 538 U.S. at 273 (citations and quotations omitted). 
See also, e.g., Carcieri v. Salazar, 555 U.S. 379, 395 (2009) 
(same); Nat'l Ass'n of Home Builders, 551 U.S. at 662 (``We will not 
infer a statutory repeal unless the later statute expressly 
contradict[s] the original act or unless such a construction is 
absolutely necessary . . . in order that [the] words [of the later 
statute] shall have any meaning at all.'') (quotations and citations 
omitted, alterations in original); J.E.M. AG Supply, Inc., 534 U.S. 
at 142-43 (``The only permissible justification for a repeal by 
implication is when the earlier and later statutes are 
irreconcilable.'').
    \45\ Radzanower v. Touche Ross & Co., 426 U.S. 148, 154 (1976). 
See also N.Y. Republican State Comm. v. SEC, 927 F.3d 499, 507 (D.C. 
Cir.2019) (quoting Radzanower).
---------------------------------------------------------------------------

    Next, we do not believe the specific mention of Sec.  30111 in 
paragraph (c), and the absence of such an explicit reference to Sec.  
30111 in paragraphs (a) or (b), should be read to suggest that Congress 
intended the Sec.  30111 criteria to apply only to subsequent revisions 
of FMVSS No. 108 (i.e., amendments to FMVSS No. 108 after NHTSA 
completes the ADB rulemaking mandated in paragraph (b)). The Agency 
acknowledges that, when Congress includes particular language in one 
section of a statute and omits it in another section of that statute, 
one canon of statutory construction (sometimes referred to as expressio 
unius est exclusio alterius) holds that Congress acts intentionally and 
purposely in the disparate inclusion or exclusion.\46\ However, to 
begin with, this canon is not clearly applicable here because paragraph 
(b) directs the agency to ``amend[ ]'' ``Standard 108.'' Because an 
FMVSS is required to meet the Sec.  30111 criteria, paragraph (b) 
implicitly references Sec.  30111, including, among other things, the 
requirement that the standard meet the need for safety.
---------------------------------------------------------------------------

    \46\ See, e.g., Cheney Railroad. Co., Inc. v. ICC, 902 F.2d 66, 
68 (D.C. Cir. 1990) (``[E]xplicit direction for something in one 
provision, and its absence in a parallel provision, implies an 
intent to negate it in the second context.'') (quotations and 
citations omitted). But see, e.g., Carter v. Office of Workers' 
Comp. Programs, 751 F.2d 1398 (D.C. Cir. 1985) (``That maxim has 
force, however, only when there is no apparent reason for the 
inclusion of one disposition and the omission of a parallel 
disposition except the desire to achieve disparate results'').
---------------------------------------------------------------------------

    Moreover, to construe the reference to Sec.  30111 in paragraph (c) 
and the omission of such an explicit reference in paragraph (b) as 
implying that the omission in (b) was intentional and evinced a 
Congressional intent that the Safety Act not apply to the ADB 
rulemaking would be to read paragraph (c) as implicitly repealing the 
Safety Act in this instance. Courts have recognized that it is 
especially inappropriate to apply the expressio canon when its 
application would result in an implied repeal, explaining ``when one 
possible

[[Page 9923]]

interpretation of a statutory provision has the potential to render 
another provision inert . . . the canon's relevance and applicability 
must be assessed within the context of the entire statutory 
framework.'' \47\ Accordingly, ``the canon is a poor indicator of 
Congress' intent'' when ``counterveiled by a broad grant of authority 
contained within the same statutory scheme.'' \48\ A negative 
inference, therefore, should only be drawn if there is an ``unambiguous 
suggest[ion that] Congress intended to strip'' an agency of its 
counterveiling ``broad grant of authority.'' \49\ As we have discussed 
above, such an intent is not present here. Further, it would not make 
sense to say that Sec.  30111 applies to revisions to the 2016 version 
of SAE J3069 but not to the 2016 version itself. And it would be odd to 
view paragraph (c) as a limitation on agency authority when it 
expressly reserves agency authority. We therefore conclude that 
paragraph (c) should not be read to preclude NHTSA from issuing a final 
rule that imposes requirements beyond SAE J3069 if the agency concludes 
that SAE J3069 does not meet the need for safety under the Safety Act.
---------------------------------------------------------------------------

    \47\ Adirondack Med. Ctr. v. Sebelius, 740 F.3d 692, 697 (D.C. 
Cir. 2014).
    \48\ Id.
    \49\ Id. at 697-698. See also id. at 697 (``The expressio unius 
canon is a feeble helper in an administrative setting, where 
Congress is presumed to have left to reasonable agency discretion 
questions that it has not directly resolved . . . The dizzying array 
of other canons that could shift the analysis one way or another--
e.g., . . . the presumption against implied repeals, militates 
against finding unambiguous congressional intent here'') (quotations 
and citations omitted). See also, e.g., Cheney Railroad. Co., Inc. 
at 69-69 (same); U.S. v. City of New York, 359 F.3d 83, 98 (2nd. 
Cir. 2004) (``[S]ince not every silence is pregnant, expressio unius 
is an uncertain guide to interpretation.'') (quotations and 
citations omitted).
---------------------------------------------------------------------------

    In addition, we are unaware of any instances in which Congress 
required NHTSA to issue or amend an FMVSS to enact or incorporate by 
reference a consensus standard without reference to the Sec.  30111 
criteria. The closest precedent of which we are aware is that the 1966 
Safety Act directed NHTSA's predecessor agency to issue initial FMVSS 
``based on existing safety standards.'' \50\ Those ``existing 
standards'' ``were understood to be the [General Services 
Administration] standards then in effect for government vehicles.'' 
\51\ However, the initial standards were not required to be identical 
to those ``existing standards,'' only to be ``based on'' them; 
consistent with this, the initial FMVSS did not simply copy existing 
standards.\52\ Moreover, the 1966 Act went on to direct that, after 
issuing the initial FMVSS, the agency ``shall issue new and revised 
Federal motor vehicle safety standards under this title'' within two 
years from the enactment of the Act.\53\ This shows, if anything, a 
general Congressional preference for providing NHTSA with at least some 
discretion over the content of the standards.
---------------------------------------------------------------------------

    \50\ National Traffic and Motor Vehicle Safety Act of 1966, 
Public Law 89-563, 103(h) (1966) (``The Secretary shall issue 
initial Federal motor vehicle safety standards based upon existing 
safety standards on or before January 31, 1967. On or before January 
31, 1968, the Secretary shall issue new and revised Federal motor 
vehicle safety standards under this title.'').
    \51\ Jerry L. Mashaw & David L. Harfst, From Command And Control 
To Collaboration And Deference: The Transformation Of Auto Safety 
Regulation, 34 Yale J. on Reg. 167, 199 n. 106 (2017).
    \52\ See, e.g., 32 FR 10812 (July 22, 1967) (NPRM for initial 
FMVSS 109) (``In drafting these proposed standards, the Bureau 
considered the comments received in response to the Advance Notice 
of Proposed Rule Making published in the Federal Register on 
February 3, 1967 (32 FR. 2417) and consultation with the National 
Motor Vehicle Safety Advisory Council and with representatives of 
the Federal Trade Commission, the General Services Administration, 
the National Bureau of Standards, and tire and auto industry 
associations, both domestic and foreign.'').
    \53\ National Traffic and Motor Vehicle Safety Act of 1966, 
Public Law 89-563, 103(h) (1966).
---------------------------------------------------------------------------

    Today's final rule is therefore consistent with the Sec.  24212 
mandate. The rule amends FMVSS No. 108 to allow for the use of ADB 
systems. While NHTSA has modified the proposal to follow SAE J3069 more 
closely where warranted, the final rule includes some requirements 
(such as test scenarios) not included in SAE J3069. NHTSA has concluded 
that these deviations from SAE J3069 are--pursuant to the Safety Act--
necessary for the final rule to meet the need for motor vehicle safety, 
because SAE J3069 does not adequately address the safety needs of 
visibility and glare prevention. The final rule, however, does not 
conflict with ADB systems that meet the performance requirements of SAE 
J3069 because a headlamp designed to comply with NHTSA's final rule can 
also be designed to conform with SAE J3069. The differences between the 
final rule and SAE J3069, as well as our test data on the performance 
of ADB systems tested to both the final rule and J3069 are described in 
detail throughout this preamble.

V. Summary of the NPRM

Proposed Requirements and Test Procedures

    NHTSA tentatively concluded that because ADB technology has the 
potential to provide safety benefits in preventing collisions with 
pedestrians, animals, and roadside objects--while not increasing 
glare--FMVSS No. 108 should be amended to permit it.
    NHTSA further tentatively concluded that to ensure ADB systems 
operate safely, the standard should be amended to include additional 
requirements specific to ADB systems. The existing headlamp 
requirements (including the requirements for semiautomatic beam 
switching devices) have two features that make them ill-suited to 
evaluate ADB performance. First, they are component-level requirements 
that involve testing the performance of an individual headlamp in a 
laboratory; they do not evaluate the performance of the headlamp system 
on the vehicle as it is driven on the road, which is particularly 
important for ADB because it adapts to roadway conditions. Second, the 
preexisting semiautomatic beam switching device requirements are only 
related to which of two beams (upper or lower) are appropriate. They do 
not contemplate an adaptive beam that is capable of dynamically 
producing many different beam patterns in response to vehicles and 
other object in the road. For example, the sensitivity test for 
semiautomatic beam switching devices currently tests the ability of the 
device to switch between a lower and upper beam when exposed to a light 
source in a controlled laboratory setting.
    These requirements would accordingly not evaluate the performance 
of an ADB system as it adapts the beam when driven on an actual road in 
the presence of other vehicles. In particular, because ADB systems use 
relatively new technology to dynamically change the beam to accommodate 
the presence of other vehicles, they have the potential--if not 
designed otherwise--to glare other motorists. This could create safety 
risks for those other motorists. We therefore proposed amending the 
standard to include vehicle-level track-tested requirements 
specifically tailored to evaluate whether an ADB system functions 
safely and limits glare for other motorists. We also proposed a set of 
component-level laboratory-tested requirements to ensure that ADB 
systems always provide adequate visibility; some of these requirements 
were also related to glare. Below, we briefly summarize the proposed 
requirements. For additional information and detail, the reader is 
referred to the NPRM.\54\
---------------------------------------------------------------------------

    \54\ See pp. 51777-51789.

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

[[Page 9924]]

Vehicle-Level Track Test To Evaluate Glare

    The centerpiece of the proposal was a vehicle-level track test to 
evaluate ADB performance in recognizing and limiting glaring for other 
vehicles. We proposed evaluating the performance of an ADB-equipped 
vehicle (test vehicle) in a variety of different types of interactions 
with either an oncoming or preceding vehicle (referred to as a 
``stimulus'' vehicle because it stimulates a response from the ADB 
system). The stimulus vehicle would be equipped with sensors near the 
driver's eyes (or rearview mirrors) to measure the illuminance from the 
ADB headlamps. The illuminance falling on the stimulus vehicle would be 
measured and recorded throughout the test run.
    To evaluate ADB performance, we proposed a set of maximum allowed 
illuminance values (glare limits). These are numeric illuminance values 
that would be the maximum illuminance the ADB system would be permitted 
to cast on the stimulus vehicle during the track test. See Table 2. We 
proposed sampling illuminance values throughout the proposed 
measurement ranges (also referred to in this document as measurement 
distances). The proposed compliance criterion was that any recorded 
illuminance value greater than the applicable glare limit would be 
considered a test failure, except that values above the applicable 
glare limit lasting no longer than 0.1 second(s) or over a distance of 
no longer than 1 m would not be considered test failures. This 
adjustment was intended to allow for electric noise in the photometers 
(i.e., any electrical signal whose source is not a result of changes in 
illuminance) as well as momentary changes in vehicle pitch.

             Table 2--Proposed Maximum Illuminance Criteria
------------------------------------------------------------------------
                           Maximum illuminance
  Measurement distance      oncoming direction      Maximum illuminance
          (m)                     (lux)            same direction  (lux)
------------------------------------------------------------------------
       15.0 to 29.9                      3.1                    18.9
       30.0 to 59.9                      1.8                    18.9
      60.0 to 119.9                      0.6                     4.0
       120.0 to 220                      0.3                     N/A
------------------------------------------------------------------------

    The proposal specified a broad set of potential stimulus vehicles. 
We proposed using any FMVSS-certified vehicle from the five model years 
preceding the model year of the test vehicle, subject to a specified 
height constraint that was intended to exclude unusually high- or low-
riding vehicles.
    We proposed a variety of scenarios to dynamically assess ADB system 
performance. We proposed three basic maneuvers for testing compliance: 
oncoming (where the test and stimulus vehicles approach each other 
traveling in opposite directions); same direction/same lane (where the 
stimulus vehicle precedes the test vehicle in the same lane); and same 
direction/passing with one vehicle (either the stimulus or test 
vehicle) traveling faster than and overtaking the other vehicle. We 
also proposed scenarios where the stimulus vehicle was stationary.
    We proposed to test each type of maneuver at various test and 
stimulus vehicle speeds (from 0 to 70 mph) on both a straight test path 
and on left and right curves of varying radii: A ``short'' curve (with 
radii from 98 m to 116 m), a ``medium'' curve (223 m to 241 m), and a 
``large'' curve (335 m to 396 m). The proposal also included a variety 
of related test procedures and conditions, such as adjusting for 
ambient light, the condition of the road surface, and the number of 
lanes. The proposed glare limits and test procedures were based on 
extensive agency research and testing.\55\
---------------------------------------------------------------------------

    \55\ See Section VII, NHTSA Research and Testing.
---------------------------------------------------------------------------

Component-Level Laboratory Photometric Testing

    The NPRM also proposed component-level laboratory-tested headlamp 
photometry requirements for the adaptive beams. We proposed to require 
that the part of the adaptive driving beam that is cast near other 
vehicles (the area of reduced intensity) must conform to the Table XIX 
lower beam photometry requirements (i.e., maxima and minima). We 
similarly proposed that the part of the adaptive beam cast onto areas 
of the roadway not occupied by other vehicles (area of unreduced 
intensity) conform with the Table XVIII upper beam photometric maxima 
and minima.\56\ These proposed requirements were intended to act as a 
complement to the track test in ensuring other motorists were not 
glared (the photometric maxima) and to ensure a minimum level of 
visibility (the photometric minima), an aspect not evaluated in the 
track test.
---------------------------------------------------------------------------

    \56\ While the NPRM used the terms ``dimmed area'' and 
``undimmed area,'' this document and the final regulatory text use 
the terms ``area of reduced intensity'' and ``area of unreduced 
intensity'' to more closely follow the terminology in SAE J3069.
---------------------------------------------------------------------------

Other System Requirements

    The standard has long specified a variety of requirements 
specifically for semiautomatic beam switching devices (in S9.4.1 and 
S14.9.3.11). The proposal extended some but not all of these 
requirements to ADB systems.
    The proposal extended the existing requirements for manual 
override, fail-safe operation (i.e., a failure of the automatic control 
portion of the device must not result in loss of manual beam switching 
control), and an automatic dimming indicator.\57\
---------------------------------------------------------------------------

    \57\ S9.4.1.
---------------------------------------------------------------------------

    The proposal did not extend the existing semiautomatic beam 
switching device requirements for lens accessibility or mounting 
height. It also did not extend any of the existing physical test 
requirements to ADB systems.\58\ These include the sensitivity test 
mentioned above, as well as tests such as a corrosion test and a 
temperature test. We proposed not subjecting ADB systems to these 
requirements for two reasons. First, as noted above, those requirements 
date from the 1960s and, accordingly, many of them (such as the 
sensitivity test) do not usefully extend to modern ADB technologies. 
Second, we tentatively believed that market forces would ensure an ADB 
system's switching device will operate robustly with respect to 
environmental conditions.
---------------------------------------------------------------------------

    \58\ S14.9.3.11.
---------------------------------------------------------------------------

    We also proposed additional requirements for ADB systems that are 
not currently required for semiautomatic beam switching devices. This 
included requirements related to fault detection and a requirement that 
the ADB system must produce a lower beam at speeds below 25 mph.

Regulatory Alternatives

    The NPRM identified two main alternatives to the proposed

[[Page 9925]]

requirements and test procedures: the ECE ADB requirements and SAE 
J3069. As noted earlier, however, the ECE requirements are not 
sufficiently objective to be incorporated into an FMVSS. Accordingly, 
the main regulatory alternative we considered was SAE J3069.
    The proposal followed SAE J3069 in many respects but deviated from 
it in several significant ways. These differences are briefly discussed 
below and summarized in Table 3. The proposal identified the deviations 
from SAE J3069 and provided a tentative justification for those 
deviations. The proposal sought comment on the relative merits of the 
proposal and SAE J3069 in all of these respects.
    Vehicle-level track test to evaluate glare. Both the proposal and 
SAE J3069 specified a vehicle-level track test to evaluate glare. The 
proposed glare limits were essentially identical to the glare limits in 
SAE J3069. The proposed track test, however, significantly differed 
from the SAE standard in four main ways: it utilized actual stimulus 
vehicles, not test fixtures; it proposed actual curves, not simulated 
curves; it included a large set of test scenarios, including scenarios 
with a moving stimulus vehicle, and complex vehicle maneuvers (e.g., 
passing scenarios); and, finally, it specified different data 
measurement and allowance procedures.
    Component-level laboratory photometric testing. The proposal 
applied more of the current component-level photometric requirements to 
the ADB system to regulate both glare and visibility. With respect to 
glare, while we proposed to require that the area of reduced intensity 
not exceed the current lower beam maxima, and the area of unreduced 
intensity not exceed the current upper beam maxima, SAE J3069 requires 
only the former. With respect to visibility, we proposed that the area 
of reduced intensity meet the lower beam minima and the area of 
unreduced intensity meet the upper beam minima; SAE J3069 only 
specifies the lower beam minima for the area of unreduced intensity.
    Other system requirements. The proposed telltale and malfunction 
requirements were similar to the requirements in SAE J3069. The 
proposal mainly differed from SAE J3069 in specifying a minimum 
activation speed, and in not applying any physical test requirements to 
ADB systems.

                      Table 3--Summary of Major Differences Between the NPRM and SAE J3069
----------------------------------------------------------------------------------------------------------------
           Test elements                              NPRM                                SAE J3069
----------------------------------------------------------------------------------------------------------------
Vehicle-level track test to
 evaluate glare:
Stimulus...........................  Broad range of stimulus vehicles.....  Test fixtures.
Test track geometry................  Specifies actual curves of various     Specifies a straight path and uses
                                      sizes.                                 fixture placement to simulates
                                                                             curves.
Test scenarios.....................  Specified scenarios with moving and    Specified smaller set of less
                                      stationary stimulus vehicles and a     complex scenarios.
                                      variety of road geometries.
Data measurement and glare limit     Applies the glare limits throughout    Applies the glare limits only at 30
 applicability.                       the measurement range specified for    m, 60 m, 120 m, and 155 m.
                                      each scenario.                        Sampling rate of at least 10 Hz.
                                     Sampling rate of at least 200 Hz.....
Compliance criteria................  Specified allowance for momentary      Allows measured illuminance to
                                      glare exceedances.                     exceed an applicable glare limit if
                                                                             it does not exceed 125% of the
                                                                             lower beam illuminance under the
                                                                             same conditions.
Component-level laboratory test:
Area of reduced intensity..........  Specified lower beam (Table XIX)       Specifies lower beam maxima.
                                      minima and maxima.
Area of unreduced intensity........  Specified upper beam (Table XVIII)     Specifies lower beam minima.
                                      minima and maxima.
Minimum activation speed...........  25 mph...............................  Not specified.
----------------------------------------------------------------------------------------------------------------

VI. Overview of Comments

    NHTSA received 217 comments on the proposal. This included comments 
from 32 vehicle and equipment manufacturers, industry groups,\59\ and 
test laboratories, as well as 5 comments from public interest groups. 
We also received comments from 19 owner/operators of drive-in movie 
theatres, including the United Drive-In Theatre Owners Association. The 
balance of the comments was from individual members of the public. An 
index of comments cited in this preamble along with the comment 
identification numbers is provided in Appendix D.
---------------------------------------------------------------------------

    \59\ Global Automakers and the Alliance of Automobile 
Manufacturers each commented during the comment period. After the 
comment period had ended, they merged to form the Alliance for 
Automotive Innovation. The Alliance for Automotive Innovation 
subsequently commented on this rulemaking. Comments from each of 
these three entities are summarized and identified by reference to 
the entity that submitted the comment.
---------------------------------------------------------------------------

    All industry and public-interest commenters supported amending the 
standard to allow the introduction of ADB systems. A majority of the 
industry commenters and the Competitive Enterprise Institute (CEI) 
strongly supported closer harmonization with SAE J3069 (or with the ECE 
requirements).\60\ These comments focused primarily on costs from 
disharmonization due to the resulting need for market-specific 
hardware, components, and/or software. Several commenters argued that 
the increased costs associated with the proposal would increase 
consumer costs and hinder ADB adoption and the concomitant safety 
benefits. Several industry commenters and the Insurance Institute for 
Highway Safety (IIHS) stated that the proposal did not maximize overall 
benefits because it prioritized glare prevention over enhanced 
visibility, and opined that the final rule should place greater weight 
on the benefits associated with enhanced visibility.
---------------------------------------------------------------------------

    \60\ SAE, on behalf of the SAE lighting systems group (which 
developed SAE J3069) submitted a detailed comment that touched on 
harmonization as well as a variety of other issues. A majority of 
industry commenters explicitly supported SAE's comments.
---------------------------------------------------------------------------

    Drive-in theatre owner/operators stressed the importance of the ADB 
system providing a means for manual headlamp control. Many indicated 
some level of support for the rule (assuming

[[Page 9926]]

it provides for manual control). The majority of comments from 
individual members of the public supported the proposal, often on the 
grounds that it would likely reduce glare or increase safety. A number 
of these commenters noted the availability of this technology in 
Europe. Several individuals who opposed the proposal thought that it 
would increase glare.
    With respect to specific aspects of the proposal, while most 
industry and public-interest groups supported a track test, many of 
these commenters argued that the specific track test in the proposal 
was impracticable and excessively burdensome, especially with respect 
to the number and complexity of test scenarios and the use of stimulus 
vehicles instead of fixtures. These commenters especially focused on 
the broad set of proposed stimulus vehicles. Some industry commenters 
also raised concerns with the objectivity and repeatability of the test 
procedure. Many industry commenters also opposed the use of a curved 
test path; they recommended that curved test paths be simulated with 
the placement of test fixtures relative to a straight test path. Many 
of these commenters also stated that the final rule should provide less 
stringent compliance criteria and provide a greater allowance for 
illuminance levels above the proposed glare limits (for example, by 
evaluating the ratio of ADB illuminance to lower beam illuminance or 
allowing additional time for an ADB system to react to the test 
stimulus). Industry commenters also raised issues about other aspects 
of the test procedures, such as data filtering and vehicle pitch.
    The agency also received comments about the proposed component-
level laboratory test requirements. A few industry commenters 
(including SAE) contended that component-level testing is unnecessary, 
while some industry members and public-interest groups supported 
aspects of the laboratory test requirements. Many industry commenters 
pointed out the need for a transition zone between areas of reduced and 
unreduced intensity. Multiple industry commenters and some public-
interest commenters recommended not requiring the lower beam minima in 
areas of reduced intensity in order to realize the full glare-reducing 
potential of ADB technology. Several industry commenters also suggested 
specifying the lower beam minima, not the upper beam minima, in areas 
of unreduced intensity. Some industry and public-interest commenters 
supported increasing the maxima in an area of unreduced intensity to 
the higher level allowed in Europe. Several industry commenters 
requested NHTSA clarify certain terms in the regulatory text.
    We also received comments about other system requirements, 
including the minimum ADB activation speed, operator controls, 
telltales, and headlamp mounting requirements.

VII. NHTSA Research and Testing

Research Before the NPRM

    Two NHTSA research studies formed the basis for the NPRM. (This 
research was necessary because, among other things, the current 
photometry requirements are laboratory-tested component-level 
requirements, not vehicle-level requirements tested on a track.) In 
2012, the agency published a study (Feasibility Study) \61\ exploring 
the feasibility of new approaches to regulating vehicle lighting 
performance, including headlamp photometry. Among other things, the 
study presented vehicle-based headlamp photometry requirements derived 
from the current component-level photometry requirements in Tables 
XVIII (upper beam) and XIX (lower beam). This included vehicle-based 
photometry requirements to ensure that other vehicles are not glared. 
NHTSA then built on this effort by developing a vehicle-level track 
test to evaluate whether an ADB system conforms with the derived 
photometry requirements for glare prevention (2015 ADB Test 
Report).\62\ For more information on this research, the reader is 
referred to the NPRM \63\ and the docketed research reports.
---------------------------------------------------------------------------

    \61\ Michael J. Flannagan & John M. Sullivan. 2011. Feasibility 
of New Approaches for the Regulation of Motor Vehicle Lighting 
Performance. Washington, DC: National Highway Traffic Safety 
Administration (NHTSA-2018-0090-0002). See also 77 FR 40843 (July 
11, 2012) (request for comments on the report).
    \62\ Elizabeth Mazzae, G.H. Scott Baldwin, Adam Andrella, & 
Larry A. Smith. 2015. Adaptive Driving Beam Headlighting System 
Glare Assessment, DOT HS 812 174. Washington, DC: National Highway 
Traffic Safety Administration (NHTSA-2018-0090-0003).
    \63\ See NPRM, pp. 51773-51774.
---------------------------------------------------------------------------

Research After the NPRM

    After reviewing the comments on the NPRM, NHTSA explored 
opportunities to modify the proposal to resemble SAE J3069 more 
closely, while at the same time retaining a sufficient degree of 
realism the agency believes the SAE standard lacks. Most significantly, 
NHTSA explored using stationary test fixtures instead of dynamic 
stimulus vehicles. NHTSA developed and fabricated test fixtures that 
were similar to the fixtures specified in SAE J3069 but differed in 
some important respects (this is discussed below). NHTSA developed a 
modified version of the NPRM test procedure (including a simplified set 
of test scenarios) using the test fixtures. NHTSA then carried out a 
series of preliminary and full-scale vehicle tests to develop and 
validate those test procedures. Those test procedures are the same test 
procedures specified in this final rule. The research also documented 
testing details to support the laboratory test procedure manual that 
will be used by NHTSA's Office of Vehicle Safety Compliance (OVSC).\64\
---------------------------------------------------------------------------

    \64\ The OVSC laboratory procedures are not part the regulatory 
text. Published separately by OVSC, they are intended to provide 
laboratories contracted by NHTSA with additional guidelines for 
obtaining compliance test data.
---------------------------------------------------------------------------

    NHTSA used the following three vehicles in the test program.
     2019 Ford Fusion equipped with FMVSS-certified halogen 
headlamps;
    [cir] Selected because it was a high-sales vehicle with halogen 
headlamps compliant with FMVSS No. 108, and the vehicle was readily 
available at NHTSA's Vehicle Research and Testing Center (VRTC).
     2016 Volvo XC90 equipped with FMVSS-certified LED 
headlamps;
    [cir] Selected because it was equipped with LED headlamps rated 
``Acceptable'' by IIHS, and the vehicle was readily available at 
NHTSA's VRTC.
     2018 Lexus NX300 (European mass production model) equipped 
with ADB LED headlamps modified by the manufacturer to be consistent 
with a visually optically aligned right (VOR) beam pattern used in the 
United States.
    [cir] Selected because it was equipped with an ADB system, modified 
to project lower and upper beam patterns compliant with FMVSS No. 108.

Preliminary Test Development and Validation

    NHTSA created a test fixture to accommodate both the NHTSA and SAE 
test procedures. The test fixture positioned a vertical array of 
illuminance meter light sensors (i.e., receptor heads) in specified 
positions and provided accurate positioning for the various NHTSA and 
SAE lamp configurations. The configurations included stimulus lamps 
specified in today's final rule: MY 2018 Ford F-150 headlamps and 
taillamps, MY 2018 Toyota Camry headlamps and taillamps, and a MY 2018 
Harley Davidson motorcycle taillamp,\65\ and the lamps

[[Page 9927]]

specified in SAE J3069 intended to simulate headlamps and taillamps. 
This single test fixture was able to accommodate needed light sensor 
configurations for both oncoming and same direction test scenarios.
---------------------------------------------------------------------------

    \65\ To represent a motorcycle headlamp, this testing used a 
5.75 inch bullet headlamp kit from a 2018 Harley Davidson Roadster 
using an HB2 replaceable light source (part #68593-06). After this 
testing and before the publication of this final rule, that part 
went out of production and has been replaced with part #68297-05B.
---------------------------------------------------------------------------

    As an important initial step as part of the research, NHTSA 
evaluated the stability of the measured illuminance values without a 
test vehicle present to determine the level of noise (if any) in the 
measurement system that was not dependent on the vehicle being tested. 
For each stimulus lamp condition, illuminance data were recorded for a 
period of 30 seconds in typical test conditions. The results indicated 
that both the analog and digital data, measured at frequency over time, 
demonstrated low standard deviations for each of the receptor heads for 
each of the ten test lamp conditions, suggesting very little system 
noise or fluctuation from ambient conditions. In fact, each lamp 
condition had at least two receptor heads that exhibited no variability 
(standard deviation = 0) in the digital data. Thus, the illuminance 
meter outputs appeared to be stable.
    Testing of the three vehicle models with headlighting systems 
operating in lower beam mode showed that the measurement system and the 
headlamp types tested, halogen and LED, were compatible with the test 
equipment (i.e., no abnormalities in measurements were observed based 
upon the type of headlighting system).
    NHTSA performed tests to assess whether test scenarios could be 
executed with sufficiently steady vehicle dynamics such that, in lower 
beam mode, headlamp illumination measured during the dynamic test 
scenario would match that measured in the same location with the 
vehicle stationary. Measured illuminance and pitch data values were 
extracted for both dynamic and static test trials at specific scenario 
path points corresponding to an end of a glare limit distance range. 
This study found that dynamically-influenced variation was not a major 
contributor to variability in the test. Pitch was found to have a major 
influence on illuminance measurements; however, the sources of pitch 
variance were primarily static in nature (resulting from waviness in 
the track pavement) and not dynamic (acceleration, or dynamic 
oscillations).

Full-Scale Validation Testing

    After successfully completing this preliminary evaluative testing, 
NHTSA proceeded to validate the final test procedure by performing 
three sets of full-scale tests.
    In the first set of tests, the ADB-equipped Lexus NX300 was 
subjected (in ADB mode) to the final rule test procedure as well as the 
SAE test procedure. We also evaluated ADB system performance using a 
full F-150 vehicle as a stimulus instead of a test fixture. In general, 
the ADB system installed on the tested vehicle responded similarly to 
the test fixture as it did to the full stimulus vehicle.
    In the second set of tests, the agency subjected all three test 
vehicles with headlighting systems operating in lower beam mode to the 
NHTSA ADB test procedure. Measured illuminance values were evaluated 
with respect to the glare limit criteria. The lower beams of the Ford 
Fusion had passing results below the glare limits in all test 
scenarios, while the lower beams of the Lexus NX300 did not pass 
several of the test scenarios when illuminance values were compared to 
the glare limits. The Volvo lower beams performed well under the limits 
for the straight and left curve scenarios, but exceeded the limits 
finalized today for the right curves.
    In the third set of validation tests, the agency conducted a series 
of tests using the 2016 Volvo XC90 with the lower beams activated to 
determine the repeatability of measured illuminance values and test 
outcomes for both the final rule and SAE test procedures. Testing 
involving multiple runs of each test scenario was conducted to permit 
different types of repeatability analyses, including same night 
(gauge); different night (test procedure); and different headlamp 
aiming technician (reproducibility). The repeated testing was performed 
to support an assessment of the repeatability of measured illuminance 
values and test outcomes for the final rule's ADB test procedure (as 
well as the SAE test procedure). A summary of the agency's 
repeatability analysis is presented in Section VIII.C.11. The full 
results of NHTSA's test procedure repeatability and reproducibility 
analyses are detailed in the repeatability report docketed with this 
final rule.\66\ The test procedures reported in that document are the 
same as the procedures used in the first and second sets of validation 
tests described above. NHTSA is also docketing a full test report more 
fully describing the agency's testing.\67\
---------------------------------------------------------------------------

    \66\ Mazzae, E.N., Baldwin, G.H.S., Satterfield, K., & Browning, 
D.A. 2021. Adaptive Driving Beam Headlamps Test Repeatability 
Assessment. Washington, DC: National Highway Traffic Safety 
Administration.
    \67\ Mazzae, E.N., Baldwin, G.H.S., Satterfield, K., Browning, 
D.A., & Andrella, A.T. 2021. Adaptive Driving Beam Headlighting 
Systems Rulemaking Support Testing. Washington, DC: National Highway 
Traffic Safety Administration.
---------------------------------------------------------------------------

VIII. Final Rule and Response to Comments

A. Summary of the Final Rule and Modifications to the NPRM

    The major components of the final rule are summarized below, 
including the most significant differences between the final rule and 
the NPRM. Less significant changes are discussed in the appropriate 
sections of the preamble.
Vehicle-Level Track Test To Evaluate Glare
    The final rule retains the track test but departs from the proposal 
in a few ways.
    Stimulus test fixtures instead of stimulus vehicles. The final rule 
specifies the use of test fixtures instead of stimulus vehicles. This 
change will result in a less complex test more closely harmonized with 
SAE J3069, while still ensuring that ADB systems operate safely. While 
the test fixture specifications follow the SAE J3069 specifications 
with respect to the locations of the photometers and stimulus lamps, 
the final rule requires the use of more real-world representative 
lighting by specifying original equipment vehicle headlamps and 
taillamps.
    More efficient test scenarios. The final rule substantially 
simplifies the number and complexity of test scenarios. Because the 
final rule specifies stimulus test fixtures and not stimulus vehicles, 
all scenarios involving a moving stimulus vehicle (e.g., passing 
scenarios) were eliminated. While the final rule retains oncoming and 
preceding scenarios \68\ with a curved test path, the agency modified 
the measurement distances and eliminated some scenarios entirely 
because they were deemed unnecessary. With respect to oncoming 
scenarios, the straight and large left curve scenarios are retained 
essentially as proposed, and the short-radius right curve scenario has 
been eliminated. The final rule retains scenarios with other proposed 
curves but truncates the distances at which ADB illuminance is 
evaluated. With respect to preceding glare scenarios, the final rule 
retains (with truncated measurement distances) the straight and medium 
left curve scenarios. These modifications, summarized in Table 4, 
respond to comments that expressed concern about the complexity of the 
proposed testing. NHTSA believes that

[[Page 9928]]

the finalized test scenarios meet the need for motor vehicle safety by 
containing a broad range of realistic road geometries--including 
curves--and vehicle interactions while addressing possible 
redundancies.
---------------------------------------------------------------------------

    \68\ The final rule regulatory text uses the terms ``same 
direction'' and ``opposite direction'' to reflect that the final 
rule uses fixtures and not stimulus vehicles.

                                         Table 4--Summary of Modifications to the Proposed Track Test Scenarios
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                            NPRM                                                                      Final rule
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                   Stimulus     Test                                                        Test
                                    Measurement    vehicle    vehicle      Radius  (size-       Final      Measurement    vehicle      Radius  (size-
           NPRM test #             distance  (m)    speed      speed       direction) \69\      test #    distance  (m)    speed       direction) \70\
                                                    (mph)      (mph)                                                       (mph)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Oncoming (adjacent lane):
--------------------------------------------------------------------------------------------------------------------------------------------------------
    1...........................          15-220      60-70      60-70  Straight............  .........                      Dropped
                                                                                                        ------------------------------------------------
    2...........................          15-220          0      60-70  Straight............          1          15-220      60-70  Straight
                                                                                                        ------------------------------------------------
    5a..........................          15-220      25-30      25-30  Small--R............  .........                      Dropped
    5b..........................          15-220      25-30      25-30  Small--L              .........
    6a..........................          15-220          0      25-30  Small--R              .........
                                                                                                        ------------------------------------------------
    6b..........................          15-220          0      25-30  Small--L............          2         15-59.9      25-30  Small--L
                                                                                                        ------------------------------------------------
    7a..........................          15-220      40-45      40-45  Med--R                .........                      Dropped
    7b..........................          15-220      40-45      40-45  Med--L                .........
                                                                                                        ------------------------------------------------
    8a..........................          15-220          0      40-45  Med--R..............          5           15-50      40-45  Med--R
                                                                                                        ------------------------------------------------
    8b..........................          15-220          0      40-45  Med--L..............          3          15-150      40-45  Med--L
                                                                                                        ------------------------------------------------
    11a.........................          15-220      50-55      50-55  Large--R              .........                      Dropped
    11b.........................          15-220      50-55      50-55  Large--L              .........
                                                                                                        ------------------------------------------------
    N/A.........................             N/A        N/A        N/A  N/A.................          6           15-70      50-55  Large--R
                                                                                                        ------------------------------------------------
    N/A.........................             N/A        N/A        N/A  N/A.................          4          15-220      50-55  Large--L
--------------------------------------------------------------------------------------------------------------------------------------------------------
Same Direction Same Lane:
--------------------------------------------------------------------------------------------------------------------------------------------------------
    1...........................          15-220      60-70      60-70  Straight              .........                      Dropped
    5a..........................          15-220      25-30      25-30  Small--L              .........
    5b..........................          15-220      25-30      25-30  Small--R              .........
    7a..........................          15-220      40-45      40-45  Med--L                .........
    7b..........................          15-220      40-45      40-45  Med--R                .........
    11a.........................          15-220      50-55      50-55  Large--L              .........
    11b.........................          15-220      50-55      50-55  Large--R              .........
--------------------------------------------------------------------------------------------------------------------------------------------------------
Same Direction Adjacent Lane
 Fast ADB:
--------------------------------------------------------------------------------------------------------------------------------------------------------
    2...........................        15-119.9          0      60-70  Straight............          7          15-100      60-70  Straight
                                                                                                        ------------------------------------------------
    3...........................        15-119.9      40-45      60-70  Straight............  .........                      Dropped
    6a..........................        15-119.9          0      25-30  Small--R              .........
    6b..........................        15-119.9          0      25-30  Small--L              .........
    8a..........................        15-119.9          0      40-45  Med--R                .........
                                                                                                        ------------------------------------------------
    8b..........................        15-119.9          0      40-45  Med--L..............          8          15-100      40-45  Med--L
                                                                                                        ------------------------------------------------
    9a..........................        15-119.9      30-35      40-45  Med--R..............  .........                      Dropped
    9b..........................        15-119.9      30-35      40-45  Med--L                .........
    13a.........................        15-119.9      40-45      50-55  Large--R              .........
    13b.........................        15-119.9      40-45      50-55  Large--L              .........
--------------------------------------------------------------------------------------------------------------------------------------------------------
Same Direction Fast Stimulus:
--------------------------------------------------------------------------------------------------------------------------------------------------------
    4...........................        30-119.9      60-70      40-45  Straight............  .........                      Dropped
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Data measurement and allowances. The final rule makes some changes 
to how NHTSA will measure and evaluate ADB system illuminance. NHTSA 
has added a specification for a data filter. It has deleted the 
proposed International Roughness Index parameter and replaced it with 
an explicit adjustment for vehicle pitch. The proposed 0.1 second (or 1 
m) allowance for momentary glare exceedances has been modified by 
deleting the distance component and more clearly specifying how this 
adjustment will be applied. The final rule also includes additional 
specifications for the photometer.
---------------------------------------------------------------------------

    \69\ Small = 98 m-116 m; Med = 223 m-241 m; Large = 335 m-396 m.
    \70\ Small = 85 m-115 m; Med = 210 m-250 m; Large = 335 m-400 m.
---------------------------------------------------------------------------

Component-Level Laboratory Photometric Testing
    The final rule retains the proposed requirements for component-
level laboratory testing but has modified them to give manufacturers 
greater design flexibility.
    Defining ``adaptive driving beam'' as a new beam type. The final 
rule defines a new beam type, an ``adaptive driving beam,'' as ``a beam 
consisting of area(s) of reduced intensity, unreduced intensity, and 
transition zone(s).'' We eliminated the proposed regulatory text that 
referred to an area of reduced intensity as being ``designed to be 
directed towards oncoming or preceding vehicles'' and to an area of 
unreduced

[[Page 9929]]

intensity as being directed ``in other directions.'' The final rule is 
intended to provide manufacturers flexibility to decide which portions 
of the roadway will receive an area of reduced or unreduced intensity, 
subject to several requirements or constraints (such as the track test 
that evaluates glare). This will enable systems to provide an area of 
reduced intensity not only to prevent glare to oncoming or preceding 
vehicles, but also in other situations in which reduced intensity would 
be beneficial (for example, towards retroreflective signs, or on a wet 
roadway).
    Transition zone. In response to comments, the final rule also 
allows for a 1-degree transition zone between an area of reduced 
intensity and an area of unreduced intensity.
    Requirements for areas of reduced intensity. The final rule retains 
the requirement that an area of reduced intensity not exceed the lower 
beam maxima in order to help ensure that other motorists are not 
subject to glare. It also continues to require that an area of reduced 
intensity meet the lower beam minima; NHTSA believes this requirement 
is important because neither the proposal nor the final rule include 
any ``false positive'' tests to ensure that an ADB system does not 
mistakenly dim the beam in the absence of any oncoming or preceding 
vehicles.
    Requirements for areas of unreduced intensity. The final rule 
follows the NPRM and specifies the existing upper beam minima and 
maxima. In response to comments that suggested not specifying the upper 
beam minima in this area (in order to allow less illumination in 
situations in which it would be appropriate, such as towards a 
retroreflective sign), we have, as explained above, eliminated the 
proposed regulatory text that implied that an area of unreduced 
intensity should be directed towards areas of the roadway not occupied 
by other vehicles. This will allow manufacturers to design systems that 
provide an area of reduced intensity to areas of the road that are not 
occupied by other vehicles but for which it may be appropriate to 
provide less illumination than would be required by the upper beam 
minima.
    As was proposed, the final rule does not adopt the higher ECE upper 
beam maxima. While NHTSA agrees with the commenters that higher 
intensity upper beams might lead to potential safety benefits in the 
form of increased visibility in the absence of other road users, the 
agency remains concerned about the associated potential safety 
disbenefits, due to increased glare, that might result from higher 
intensity upper beams, particularly in situations in which an ADB 
system might not recognize and shade other vehicles.
Other System Requirements
    ADB minimum activation speed. The final rule retains a minimum 
activation speed but this has been decreased from 25 mph to 20 mph to 
give greater flexibility to manufacturers wishing to provide for 
hysteresis in the system design.
    Exemption from some horizontal aimability performance requirements. 
The final rule amends the headlamp horizontal aimability performance 
requirements to exempt ADB systems from many of the vehicle headlamp 
aiming device (VHAD) requirements. These requirements are not necessary 
for ADB systems and exempting ADB systems will lower costs and 
facilitate ADB deployment in the United States.

B. Interpretation of FMVSS No. 108 as Applied to ADB Systems

    Prior to the publication of the NPRM, NHTSA had not directly 
addressed whether FMVSS No. 108 permits ADB systems. In the NPRM, we 
tentatively concluded that ADB systems are not currently permitted 
under the standard because they are part of the required headlamp 
system, and, as such, would not comply with at least some of the 
headlamp requirements.\71\ We included this tentative interpretation in 
the NPRM because some manufacturers had argued that ADB systems should 
be considered supplemental lighting.\72\
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    \71\ For a more detailed discussion, see NPRM, 83 FR 51774-
51777.
    \72\ FMVSS No. 108 specifies, for each class of vehicle, 
required and optional (if-equipped) lighting elements. The standard 
sets out various performance requirements for the required and 
optional lighting elements. The standard also allows vehicles to be 
equipped with lighting not otherwise regulated as required or 
optional equipment. This type of lighting equipment is referred to 
as ``supplemental'' or auxiliary lighting. Supplemental lighting is 
permitted if it does not impair the effectiveness of lighting 
equipment required by the standard. S6.2.1.
---------------------------------------------------------------------------

    In the NPRM we went on to also consider the status of ADB 
technology if we were, instead, to consider it supplemental equipment. 
We concluded that this still might not obviate the need for this 
rulemaking because it would be difficult for NHTSA to verify that the 
system did not impair the effectiveness of any of the required 
lighting. That is, whether an ADB system is functioning properly 
depends on whether it accurately detects oncoming and preceding 
vehicles in actual operation on the road, and there would be no way to 
test this under FMVSS No. 108 as the standard had existed prior to this 
final rule.
Comments
    Several commenters (General Motors, LLC [GM], American Honda Motor 
Co., Inc. [Honda], Global Automakers [Global], Ford Motor Company 
[Ford], and the Alliance of Automobile Manufacturers [Alliance]) 
disagreed with NHTSA's proposed interpretation, and contended that ADB 
systems should be considered supplemental lighting.
Agency Response
    The interpretation set out in the NPRM (which concerned the version 
of the standard in effect prior to this final rule) is now moot because 
the final rule amends the standard to expressly allow and regulate ADB 
systems. For the same reason, ADB systems can no longer be considered 
(as suggested by the commenters) ``supplemental'' lighting because the 
rule amends the standard to expressly allow ADB systems, while at the 
same time subjecting them to a variety of requirements expressly 
intended for and unique to these systems.\73\
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    \73\ The interpretation set out in the NPRM assumed that the 
adaptive beam would always be a ``lower beam'' under the version of 
the standard predating this final rule because a ``lower beam'' is 
defined in the standard as ``a beam intended to illuminate the road 
and its environs . . . when meeting or closely following another 
vehicle.'' This assumed that in the absence of other vehicles ADB 
systems would provide a full upper beam, and not an adaptive beam. 
However, some of the commenters pointed out that an adaptive beam 
(i.e., less than a full upper beam) might also be provided in the 
absence of other vehicles (for example, in order to minimize glare 
to the driver from retroreflective signs). As we explain later in 
this preamble, the final rule allows for this type of beam design.
---------------------------------------------------------------------------

C. Track Testing Requirements and Procedures

1. Practicability of Proposed Test Scenarios
    The NPRM proposed a wide range of track test scenarios, including a 
large set of potential stimulus vehicles, varying road geometries 
(curves, straight paths), and varying vehicle speeds.\74\ NHTSA 
tentatively concluded that the proposed ranges of stimulus vehicles and 
test scenarios were appropriate to ensure that an ADB system functions 
robustly

[[Page 9930]]

and avoids glaring other drivers in a wide variety of real-world 
circumstances. The agency explained its concerns about a test procedure 
permitting an ADB system designed to accommodate only a narrow range of 
vehicles and explained that the proposed scenarios would require ADB 
systems to be able to negotiate a variety of real-world conditions. 
NHTSA tentatively concluded that the proposed testing was practicable 
but acknowledged that certain scenarios might be challenging for some 
ADB systems. The agency also explained its decision not to propose some 
common scenarios. For example, we explained that the proposal did not 
include testing ADB performance when approaching a vehicle at an 
intersection oriented perpendicular to the ADB vehicle's direction of 
travel because existing ADB systems would have a difficult time meeting 
the performance criteria in such scenarios and 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).
---------------------------------------------------------------------------

    \74\ The test matrix specifies ranges for the various test 
parameters. Other provisions in the final regulatory text also 
specify ranges of values at which various testing parameters may be 
set. The larger the range of values, the broader the parameters for 
which the vehicle much perform. Where a range of values is 
specified, the vehicle must be able to meet the requirements at all 
values within the range. In addition, the word ``any,'' used in 
connection with a range of values or set of items in the 
requirements, conditions, and procedures of an FMVSS means generally 
the totality of the items or values, any one of which may be 
selected by the agency for testing. See 49 CFR 571.4, Explanation of 
Usage.
---------------------------------------------------------------------------

Comments
    The agency received a number of comments on the practicability of 
the proposed test scenarios. Many of the commenters, including many 
vehicle and equipment manufacturers and trade associations, agreed with 
the need for track testing, but most stated that the proposed testing 
was unnecessarily broad and impracticable. Intertek supported a more 
rigorous dynamic roadway test than specified in SAE J3069, but stated 
that the full set of proposed scenarios may not be necessary and 
estimated testing costs to be two-to-four times higher than testing to 
SAE J3069. Consumer Reports and IIHS also supported a vehicle-level 
track test but stated that the proposed track test was too broad. Many 
industry members (Honda, Global, GM, SAE, Competitive Enterprise 
Institute (CEI), Toyota, Alliance, Mobileye, OSRAM Sylvania Inc. 
(OSRAM), the Motor & Equipment Manufacturers Association (MEMA), 
Infineon Technologies Americas Corp. (Infineon), Valeo Lighting Systems 
(Valeo), and NAFA Fleet Management Association (NAFA)) supported the 
use of SAE J3069, which includes a more limited track test, and/or 
specifically supported a more limited track test than proposed. 
Commenters made a variety of arguments for why they believed the 
proposed track test was not practicable.
    A number of commenters \75\ stated that the proposed track test was 
not practicable because of the number and complexity of the proposed 
scenarios. For example, SAE stated that testing over 34 different 
maneuvers on various road geometries with multiple variations is 
excessive and not practicable. IIHS similarly commented that the number 
of scenarios could be reduced to a more manageable set without 
sacrificing the tests' ability to identify systems unable to adequately 
mitigate glare. IIHS estimated that testing every scenario with all 
four types of stimulus vehicle would require 272 tests, and that 
testing at different speeds would require even more tests. Toyota 
estimated that the proposal resulted in 10,000 possible test scenarios.
---------------------------------------------------------------------------

    \75\ These were MEMA, IIHS, Toyota, Alliance, SAE, Auto 
Innovators, Honda, Global, Valeo, Volkswagen, the International 
Organization of Motor Vehicle Manufacturers (OICA), GM, Ford, and 
the Transportation Safety Equipment Institute (TSEI).
---------------------------------------------------------------------------

    Several commenters claimed that the proposal would necessitate 
testing capabilities beyond those available at existing test 
facilities. The Alliance for Automotive Innovation (Auto Innovators) 
conducted a series of tests based on the proposed scenarios and 
commented that it found that the proposed scenarios were unnecessary 
and beyond the capabilities of many proving grounds. Volkswagen, the 
Alliance, Valeo, and Auto Innovators commented that the proposed test 
scenarios necessitated test tracks with characteristics (e.g., 
specified radii of curvature, road surface conditions, test track 
length necessary for attaining specified speeds) that were not within 
the capabilities of existing proving grounds. SAE, Auto Innovators, 
OICA and the Society of Motor Manufacturers and Traders (SMMT) 
contended that the proposed track test would necessitate data 
measurement capabilities beyond those which are currently available at 
test facilities, with Auto Innovators arguing that the proposal would 
require up to 476 data elements. Auto Innovators also commented that 
the amount of time needed for data collection and processing was longer 
than expected, and it recommended that NHTSA develop software or other 
compliance tools to expedite data processing. To address these issues, 
Auto Innovators recommended (among other things) adopting fixed 
lighting stimuli, limiting the number of eligible stimulus vehicles, 
and limiting the number and complexity of test scenarios.
    A few commenters suggested eliminating redundant scenarios and/or 
testing only the most stringent scenarios. Auto Innovators suggested 
that by adopting the most stringent test scenarios at the extremes of 
the testing range, the intermediate tests could be eliminated. For 
example, Auto Innovators suggested only specifying straight and small-
radius curve scenarios because the small-radius curve was the most 
stringent test with 46 failures out of 127 valid test runs (36.2% 
failure rate), while the failure rates for the straight, mid, and large 
radius test scenarios were 26.6%, 26.7%, and 22.4%, respectively. IIHS 
stated that while the volume of proposed test scenarios might be 
justified if each scenario presented substantially different conditions 
for the ADB system, that is not the case with the proposal; an 
algorithm based on a camera sensor has limited ability to compute 
distance and vehicle type solely using another vehicle's headlamps or 
taillamps. For example, from the camera's perspective, a larger vehicle 
farther away will look the same as a smaller vehicle at a closer 
distance. As a result, ADB algorithms will be designed to the boundary 
cases of the range of scenarios NHTSA finalizes, which should allow the 
intermediate scenarios to be eliminated.
    The Truck and Engine Manufacturers Association (EMA) commented that 
the NPRM did not consider the significant barriers and expense of the 
proposal on the heavy-duty market. EMA stated that the heavy-duty 
market presents unique challenges for ADB development because of the 
wide variation of potential vehicle configurations due to extensive 
customization and low volume.\76\ EMA commented that these varied 
configurations determine the height and angle of the vehicle, and in 
the case of incomplete vehicles the angle of the chassis may change 
upon completion of the vehicle by a body-builder. EMA also commented 
that performing track-level testing on hundreds of vehicle 
configurations would be cost-prohibitive, and track-testing facilities 
are not readily accessible to manufacturers. EMA also commented that 
the NPRM did not include any data specific to heavy-duty vehicles and 
stated that such testing would be necessary before finalizing the rule. 
EMA stated it was unable to fully evaluate the proposal due to the 
immaturity of ADB technology for the heavy-duty market.
---------------------------------------------------------------------------

    \76\ EMA also commented about the impact of the driver's eye 
point and sensor positions in heavy-duty vehicles, but NHTSA was 
unsure of the meaning of this comment.

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

[[Page 9931]]

    Global commented that NHTSA should justify the fact that the 
proposal was more stringent than the current semiautomatic beam 
switching device requirements (which are limited to a test of the 
``camera'' device and do not test the overall system).
Agency Response
    NHTSA agrees that the proposal included redundant scenarios and 
that the final rule can more closely follow SAE J3069 without 
sacrificing the robustness of the test. The final rule specifies 
stationary test fixtures outfitted with vehicle lamps instead of 
dynamic stimulus vehicles. The test fixture specifications are similar 
to those specified in SAE J3069, but differ by specifying original 
equipment vehicle lamps. Accordingly, the final rule eliminates all 
scenarios involving a moving stimulus vehicle.
    NHTSA also modified the specified road geometries. The final rule 
retains scenarios with actual curves. However, considering lower beam 
and ADB system capabilities, NHTSA has narrowed down the curve 
scenarios by eliminating the short right-curve scenario and truncating 
the measurement distances for all but the large left curve scenario. 
NHTSA similarly modified the measurement distance for the preceding 
scenarios. We believe that the final test scenarios are sufficient to 
determine whether an ADB system prevents glare to other motorists. The 
reasons for these modifications are discussed in more detail in Section 
VIII.C.8, Test Scenarios and Section VIII.O, Regulatory Alternatives.
    The agency narrowed down the test scenarios by identifying aspects 
of performance that an acceptable ADB system should meet and choosing 
scenarios that would be the most challenging with respect to those 
aspects of performance. For example, the final rule includes a same-
direction left curve scenario in order to test the ability of an ADB 
system to recognize dim red lamps at wide angles.
    However, the agency's testing showed that it was not possible to 
identify a radius of curvature (e.g., shortest) that would necessarily 
present a ``worst-case'' for all aspects of an ADB system. For example, 
with the oncoming car/truck test fixture outfitted with the Camry 
headlamps on a left curve, the shorter-radius curve was, in fact, more 
challenging for the ADB system used for testing as evidenced by the 
fact that it nearly exceeded the glare limit. See Figure 2.\77\ 
However, when tested with the preceding motorcycle fixture in a left 
curve test scenario, the ADB system tested failed the test on a larger-
radius curve but passed the test on a smaller-radius curve. See Figure 
3. On the larger-radius curve, the system failed to recognize the 
motorcycle taillamp for the entirety of the test (the detectors are 
saturated at the end of the test, so it is not possible to interpret 
the results from 30 m-15 m). This suggests that a variety of test 
scenarios, including a range of different curves, are needed to test 
the variety of factors that contribute to a properly-performing ADB 
system. While in many instances, shorter-radius curves will be a worst-
case scenario, the agency does not believe such curves will necessarily 
represent the worst-case for all ADB systems; complexities in the 
recognition system can create a far more complex set of test results. 
The final rule therefore retains curves with a range of radii of 
curvature.
---------------------------------------------------------------------------

    \77\ The agency saw a similar result in its 2015 data. See 
Adaptive Driving Beam Headlighting System Glare Assessment, DOT HS 
812 174, August 2015, NHTSA U.S. Department of Transportation, p.168 
(Fig. 74). The vehicles tested as part of that research demonstrated 
a similar performance with respect to curve radius and closing 
speed. The glare was higher for the moving stimulus vehicle as 
compared to a stationary one.
[GRAPHIC] [TIFF OMITTED] TR22FE22.002

[[Page 9932]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.003

    NHTSA implemented the finalized test scenarios using readily-
available photometric measurement and processing equipment. 
Accordingly, the agency has concluded that it is within the 
capabilities of current testing facilities to test to the final 
requirements.
    The agency is not persuaded by EMA's comments regarding heavy-duty 
vehicles. Because ADB systems are not required, heavy-duty vehicle 
manufacturers may take time to fully develop ADB technologies for use 
on these vehicles. Moreover, while the development of ADB systems for 
heavy-duty vehicles is less mature than for passenger cars, the agency 
does not believe these challenges to be insurmountable, or that meeting 
the requirements of this final rule is impracticable. There are a few 
reasons for this. First, the ability of the ADB system to dynamically 
track other vehicles is independent of the specific characteristics of 
the ADB-equipped vehicle, so the fact that the ADB system would be on a 
heavy-vehicle would not be consequential. Second, the test procedures 
specify that NHTSA will aim the headlamps on the test vehicle according 
to the manufacturer's instructions, which provides manufacturers with a 
means to mitigate the effects of chassis-specific features that might 
affect system performance by establishing chassis-specific aim 
specifications. Third, the final rule's extensive modifications to the 
proposed track test, resulting in a streamlined set of test scenarios, 
should also help address concerns about heavy-vehicle testing.\78\
---------------------------------------------------------------------------

    \78\ We also note that NHTSA was unable to perform testing on 
heavy-duty vehicles because it was not aware of any such vehicles 
that are ADB-equipped. In any case, for the reasons given above, we 
do not believe that it is necessary to test heavy-duty vehicles 
prior to adopting this rule.
---------------------------------------------------------------------------

    Finally, while the requirements and test procedures in the final 
rule are an increase in stringency from the longstanding requirements 
for semiautomatic beam switching devices, this final rule is 
appropriate because ADB systems are capable of providing an enhanced 
beam that is brighter than the lower beam, which presents an increased 
risk for glare if the system is not designed appropriately.
2. Test Fixtures vs. Stimulus Vehicles
    NHTSA identified two main alternatives to the proposed broad range 
of eligible stimulus vehicles that would be used to elicit an ADB 
system response. First, the agency considered specifying a small set of 
specifically-identified stimulus vehicles, but tentatively decided that 
a broad range of potential stimulus vehicles was necessary to ensure 
that an ADB system can recognize multiple headlamp/taillamp 
configurations on vehicles of different sizes and shapes.
    Second, NHTSA considered specifying test fixtures, including those 
specified in SAE J3069.\79\ The NPRM noted SAE's rationale that 
fixtures represent a worst-case scenario because some cameras use 
movement to identify objects as vehicles. It also noted SAE's 
explanation that the fixture lamps would represent a ``reasonable worst 
case for intensity and location and should promote test 
repeatability.'' \80\ NHTSA also noted that test fixtures could be 
easier to use than actual vehicles.
---------------------------------------------------------------------------

    \79\ See NPRM at p. 51782-51783.
    \80\ SAE J3069, p. 3.
---------------------------------------------------------------------------

    However, the proposal identified several potential concerns with 
test fixtures. The major concern was the lack of realism, so that 
fixtures might not indicate whether the ADB system would recognize 
actual vehicles and instead could permit ADB systems to be tuned to 
detect fixtures. Another concern related to possible difficulties in 
tuning out non-vehicle objects. Also of concern was the possibility 
that the fixture characteristics might not represent a worst case.
    The NPRM therefore proposed a large set of eligible stimulus 
vehicles. The agency tentatively concluded that it would be practicable 
for manufacturers to design ADB systems to recognize and

[[Page 9933]]

shade any vehicle satisfying the proposed selection criteria. NHTSA 
noted that the lighting configurations an ADB system would have to 
recognize would not be unreasonably large, as front and rear lighting 
designs are limited by the requirements of FMVSS No. 108 and the 
realities of vehicle design. NHTSA also reasoned that there is a 
limited, and not exceptionally large, number of makes and models of new 
vehicles offered for sale in the United States every year 
(approximately 420), and that the set of eligible stimulus vehicles 
would be further limited by the proposed vehicle height constraint.
Comments
    Vehicle and equipment manufacturers opposed the use of stimulus 
vehicles and commented that NHTSA should instead follow SAE J3069 and 
use test fixtures. These commenters identified a variety of specific 
concerns with stimulus vehicles.
    Several commenters (Mobileye, EMA, Volkswagen, SMMT, Ford, Toyota, 
SAE, the Alliance, Global, and Honda) contended that the proposed 
stimulus vehicle specifications would result in an impracticably large 
set of potential vehicles. For example, SAE and the Alliance commented 
that the NPRM specified an unmanageable and exceptionally large number 
of potential stimulus vehicles, exacerbated by the fact that many 
vehicles have multiple headlamp and/or taillamp trim levels, and that 
the proposal does not account for motorcycles or heavy-duty vehicles. 
They estimated that this could result in a set of up to 1,000 eligible 
stimulus vehicles. The Alliance also contended that it would be 
impossible for a manufacturer to choose a worst-case scenario and 
guarantee that testing with the other thousands of vehicle choices 
would exhibit reproducible results for the multitude of requirements. 
MEMA, Volkswagen, and the Alliance commented that the proposal would 
cause manufacturers to incur costs from repeated testing as the 
stimulus vehicles need to be refreshed every year. Volkswagen also 
commented that obtaining stimulus vehicles would be especially 
burdensome for foreign original equipment manufacturers (OEMs) and test 
facilities.
    Mobileye, SAE, Honda, and Ford commented that an FMVSS requiring a 
manufacturer certification to account for the various configurations 
and performance of thousands of vehicles in the market would be 
unreasonable and unprecedented, as opposed to other FMVSS which 
simulate real-world conditions with standardized test apparatus. As an 
example, SAE, Ford, and Honda pointed to FMVSS No. 208, which uses a 
fixed barrier to simulate a stimulus vehicle crashing head on into the 
test vehicle within one specified range of speeds and does not require 
selecting actual vehicles from a large population available in the 
market to conduct this testing. Honda also pointed to FMVSS No. 214 
(side impact) and FMVSS No. 301 (rear impact), and various New Car 
Assessment Program (NCAP) test procedures that standardize the device 
used to assess the crashworthiness of the test vehicle. SAE and Honda 
contended that this approach allows the test to be practicable and 
objective, and SAE suggested such an approach would be sufficiently 
realistic because, as the NPRM noted, the lighting configurations an 
ADB system would have to recognize are limited by the requirements of 
FMVSS No. 108 and realities of vehicle design.
    Commenters also raised concerns related to vehicle production 
cycles. SAE and Ford commented that the cycle plans of any given 
vehicle design can last many years, with those designs solidified many 
months prior to production, making it impossible for manufacturers to 
account for other manufacturers' vehicles in any manageable timeframe. 
A manufacturer would not be aware of which vehicles may pose compliance 
challenges for its ADB system prior to these vehicles being sold to the 
public, especially considering the extremely conservative and 
challenging requirements associated with the NPRM. Honda made similar 
comments.
    Mobileye commented that the proposal would lead OEMs to over-tune 
the ADB system in order to ensure compliance, resulting in non-optimal 
and overly sensitive system behavior and diminished safety benefits.
    Several commenters (Global, Mobileye, Valeo, the Alliance, MEMA, 
and Volkswagen) raised concerns regarding the repeatability and/or 
reproducibility of compliance test results. SAE, the Alliance, SMMT, 
and Honda commented that the proposal was not objective.
    A few commenters did support using stimulus vehicles. Consumer 
Reports supported a broad range of stimulus vehicles as reasonable to 
adequately ensure ADB systems detect, identify, and shade vehicles of 
different size, shape, and lighting configurations; however, it also 
urged that testing be practical and efficient. Intertek commented that 
a simple static test fixture may not be sufficient, and that using any 
make or model within defined physical constraints is preferable to 
adding an appendix with a list of eligible test vehicles. AAA commented 
that no certified motor vehicle should be excluded from use as a 
stimulus vehicle, and that the proposed limitation to the past five 
model years together with the vehicle height constraints were practical 
and acceptable.
    Several commenters, while not supporting the use of actual 
vehicles, commented that if NHTSA were to use actual vehicles, it 
should further limit the set of eligible stimulus vehicles. SL 
Corporation (SL) commented that detailed criteria for stimulus vehicles 
(such as light source, luminous intensity of the stimulus vehicle's 
headlamp and rear lamp), specified by vehicle type, is needed. Global 
commented about a need for consistency in any testing, further arguing 
that the rule could bookend the vehicle population's performance (i.e., 
lowest/highest, narrowest/widest) to constrain the massive number of 
stimulus vehicles. Toyota suggested that NHTSA limit the number of 
stimulus vehicles to a practical and manageable list by only using the 
top three U.S. selling vehicle models for each of the vehicle types 
identified in Table XXI of the NPRM in the fifth model year prior to 
the model year of the certified vehicle. Honda stated that if NHTSA 
does not adopt test fixtures, it should test with a single stimulus 
vehicle chosen by the manufacturer. Valeo suggested specifying a 
standard stimulus vehicle. Mobileye suggested modifying SAE J3069 by 
defining the use of a standardized dummy stimulus vehicle with lamps 
representative of those approved by FMVSS No. 108 instead of the static 
fixtures specified in SAE J3069. Mobileye also recommended 
complementing the (modified) SAE test with a requirement for an 
additional test drive by a test engineer to ensure stable detection and 
reaction to vehicles of different makes and models in additional real-
world scenarios not specified in the track test.
Agency Response
    After evaluating the comments and considering the requirements of 
the Safety Act and the National Technology Transfer and Advancement Act 
(NTTAA),\81\ NHTSA has decided to specify test fixtures instead of 
stimulus vehicles. The NTTAA directs agencies to use voluntary 
consensus standards unless, among other things, doing so would be 
inconsistent with applicable

[[Page 9934]]

law. We believe the test fixtures specified in the final rule are 
consonant with both the Safety Act and the NTTAA.\82\ In particular, we 
believe the test fixtures both meet the need for safety and better 
align with SAE J3069 and other countries' standards.
---------------------------------------------------------------------------

    \81\ National Technology Transfer and Advancement Act of 1995, 
Public Law 104-113, 110 Stat. 775 (1996). See Section X, Rulemaking 
Analyses and Notices.
    \82\ We also note that the final rule does not adopt Mobileye's 
suggestion to supplement the track test with an evaluative drive by 
a test engineer, because such a requirement would not satisfy the 
Safety Act requirement of objectivity.
---------------------------------------------------------------------------

    Most importantly, we concluded that the test fixtures specified in 
the final rule meet the need for safety. There are two main reasons for 
this. First, in this case the need for safety requires us to balance 
visibility and glare prevention. As some commenters pointed out, a too-
demanding track test to evaluate glare, including a large set of 
eligible stimulus vehicles, could lead manufacturers to tune the system 
to provide sub-optimal forward illumination. Second, we concluded that 
using real vehicles would generally not challenge ADB systems any more 
robustly than properly-specified fixtures. In the NPRM we expressed the 
concern that insufficiently realistic test fixtures could lead to ADB 
systems with performance tuned to the fixtures, not to real vehicles, 
resulting in a test that does not sufficiently replicate real-world 
performance. To address this concern, NHTSA developed test fixtures 
fitted with original manufacturer replacement equipment vehicle 
headlamps and taillamps, instead of the lamps specified in SAE J3069 
that are intended to simulate vehicle lighting. (See Section VIII.C.6 
for a discussion of the final fixture specifications.) NHTSA then 
tested whether an ADB system performed differently with these fixtures 
than with an actual vehicle. As explained below, this testing showed 
that the ADB system detected and responded to the finalized test 
fixtures in generally the same way it did to an actual vehicle.
    NHTSA's recent research compared ADB performance when tested with 
the finalized stimulus fixtures versus a stationary stimulus (i.e., 
actual) vehicle. For the most part, differences in performance were not 
observed. For example, in straight oncoming and preceding test 
scenarios, the ADB system recognized both the stimulus vehicle and test 
fixture before either stimulus entered the measurement range. See 
Figures 4 and 5.
[GRAPHIC] [TIFF OMITTED] TR22FE22.004

[[Page 9935]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.005

    One exception to this was observed for the smallest-radius left 
curve (oncoming) at the highest speed. In this case, the ADB system 
performed better (recognized and adjusted sooner) when exposed to the 
test fixture. For the fixture, the test vehicle adjusted its light 
output at around 44 m and did not exceed the glare limits. For the real 
vehicle, it reacted at 39 m, resulting in a glare exceedance. This 
suggests that this ADB system likely relies on light source detection 
rather than using supplemental systems such as radar or LIDAR to detect 
a vehicle structure. Although we did not systematically test this 
hypothesis, we suspect that the performance differences observed in 
this case are caused by small differences in headlamp mounting heights 
between the fixture and the real vehicle. See Figure 6. The agency did 
not observe any situations in which the full vehicle was recognized, 
but the test fixture was not.

[[Page 9936]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.006

    The test fixtures specified in the final rule more closely align 
with SAE J3069 and better harmonize with other countries' standards 
than the proposed broad range of eligible stimulus vehicles. This 
should help facilitate deployment of ADB systems in the United States 
because manufacturers are already familiar with SAE J3069 and because 
it harmonizes with the Canadian regulations, which permit ADB systems 
designed to meet either ECE R123 or SAE J3069. This approach also 
results in a more manageable set of test scenarios and stimulus 
vehicles to which manufacturers must certify,\83\ which will also 
result in a less complex and costly test. Test fixtures will reduce the 
test burden by establishing a consistent stimulus for testing, reducing 
the cost of acquiring and maintaining the test stimulus, reducing the 
test time, and more closely harmonizing with SAE J3069. NHTSA's testing 
showed that fixtures simplified the coordination of each test run. A 
single test driver was required to drive the test vehicle as opposed to 
two drivers required for tests involving dynamic stimulus vehicles. 
Additionally, no start and stop coordination was needed between the two 
drivers. The use of fixtures also facilitates set-up for different 
scenarios.\84\
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    \83\ Specific to this rulemaking, NHTSA has concluded that using 
test fixtures better balances the safety needs of visibility and 
glare prevention, and is more practicable and appropriate, than 
using a broad range of potential stimulus vehicles. We are not 
implying that a large set of potential stimulus vehicles is 
necessarily impracticable for an FMVSS. We also note that we do not 
agree with the commenters who claimed that the proposal raised 
issues with respect to objectivity, repeatability, or 
reproducibility.
    \84\ NHTSA developed a single test fixture that was capable of 
mounting both the motorcycle and the car/truck vehicle lamps; the 
various lamps could be switched between test runs of different 
scenarios.
---------------------------------------------------------------------------

3. Justification for Testing on Curves and General Approach for 
Scenario Selection
    In addition to testing ADB performance in a straight-path scenario, 
the NPRM proposed testing ADB systems on curved-path scenarios (both 
left and right curves) with a variety of radii of curvature. The agency 
proposed testing on a ``small'' curve with radii of curvature from 98 
m-116 m (320-380 ft); a ``medium'' curve with radii of curvature of 223 
m-241 m (730-790 ft); and a large curve, 335 m-396 m (1100-1300 ft). 
The NPRM explained that the small curve was chosen because it 
corresponded (approximately) to the shortest radii of curvature 
appropriate for a vehicle traveling 25-35 mph, approximately the 
minimum speed for which we proposed to allow ADB activation. The medium 
curve corresponded to the shortest radii of curvature appropriate for 
the higher ADB minimum activation speeds of some of the ADB-equipped 
vehicles NHTSA tested. Finally, the large curve was intended to 
correspond to a curve appropriate for vehicles traveling at higher 
speeds, to test ADB performance on curves at higher speeds. Values for 
speed and radius of curvature were selected to be consistent with the 
simplified curve formula.\85\
---------------------------------------------------------------------------

    \85\ This is a standard formula used in road design that 
specifies the relationship between vehicle speed and the radius of 
curvature. See infra n.142 and accompanying text.
---------------------------------------------------------------------------

    The NPRM recognized that curves might present engineering 
challenges for ADB systems. For example, on a curve an oncoming vehicle 
enters the ADB system's field of view (FOV) from the edge; in a tight 
curve, an oncoming vehicle will enter the field of view at a closer 
distance than in a larger-radius curve. Performing adequately on large-
radius curves at relatively high speeds consequently presents a 
slightly different engineering challenge than performance on tight 
curves at lower speeds.
Comments
    Consumer Reports supported testing using curved path scenarios of 
various curvatures. Intertek supported a more rigorous dynamic roadway 
test than specified in SAE J3069 (which specifies straight test drive 
paths) because the SAE J3069 approach may not be sufficient to validate 
the performance of the ADB sensor over the range of situations that it 
will normally encounter.

[[Page 9937]]

    On the other hand, several commenters opposed or raised issues with 
testing on actual curves. SAE commented that NHTSA should follow SAE 
J3069 and simulate curves using a straight path and varying the 
placement of the test fixtures. SAE contended that curves are not 
necessary because continuous tracking of the angular location of the 
test fixture in straight scenarios is required, and that removing 
curves would greatly reduce the testing burden. SAE noted that it 
considered including curves in SAE J3069 but concluded that attempting 
to capture hundreds of potential road geometries would make the test 
excessively burdensome because ADB systems would function similarly 
over many of these geometries and including them all would provide no 
added value. SAE further determined that testing on a straight path 
with one lane to the right and more than one lane to the left of the 
ADB-equipped vehicle would capture the conditions necessary to 
determine whether an ADB system functions appropriately and ensures an 
adequate response to a wide variety of road geometries, while allowing 
the test method to be simple enough to be objective and repeatable. For 
example, SAE J3069 requires that in a straight-line encounter, an ADB 
system must continuously track the angular location of an opposing 
vehicle fixture as that angular position becomes increasingly further 
from the center of the camera's field of view with decreasing distance 
to the opposing vehicle. SAE commented that such an approach allows 
evaluation of vehicles encountered on curves to be captured without 
using actual curves.
    SAE, ALNA, Toyota, and the Alliance stated that the proposal would 
require ADB systems to produce less glare than current FMVSS No. 108-
compliant lower beams, and that this issue was particularly acute on 
curves. They argued that the proposed approach would reduce lower beam 
visibility and negatively impact safety. SAE provided analyses and 
graphs based on IIHS data on lower beam performance on different road 
geometries, from straight roads to left and right curves of various 
radii. Stanley and Intertek also asserted that the final rule should 
account for the fact that current lower beams would not comply with the 
glare limits on right curves.\86\
---------------------------------------------------------------------------

    \86\ The commenters' data and arguments on these points are 
discussed in more detail in the sections below discussing each of 
the test scenarios in the final rule.
---------------------------------------------------------------------------

Agency Response
    The final rule does not adopt some commenters' recommendation to 
forgo actual curved-path scenarios, but it does reduce the measurement 
distances in many of the test scenarios for which curves are specified.
    The agency is not persuaded that the SAE J3069 approach of 
simulating curves by varying fixture placement relative to a test 
vehicle's straight path adequately replicates curves. Two features of 
the SAE test are intended to replicate what the system would encounter 
in an actual curve. First, the fixtures are placed to the side of the 
test vehicle's path. Second, the sudden appearance scenario is intended 
to roughly replicate a curve in that the fixture's stimulus lamps 
become visible at a close distance, which would happen on a relatively 
tight curve. (The sudden appearance scenario is also intended to 
exercise the ability of the ADB system to react to real world 
situations such as another road user turning on their lights, turning 
onto the road, or cresting a hill at distances as close as 100 m.) This 
approach, however, does not accurately replicate real curves in at 
least two respects.
    One is the trajectory of the fixture as it is tracked by the ADB 
system (see Figure 7). An approaching vehicle on an actual curve enters 
the ADB system's field of view from the edge, at a relatively far 
distance; moves towards the center of the field of view as the distance 
to the fixture closes; and then moves out towards the edge of the field 
of view at a close distance. The trajectory is different, however, when 
attempting to replicate a curve using a straight path and fixtures 
placed out to the side. There, the fixture is first detected by the ADB 
system near the center of the camera's field of view at a far distance, 
and then moves out towards the edge of the field of view at closer 
distances.
    For example, on an actual left curve with a radius of 230 m, the 
fixture enters the FOV at the edge (25L) at a relatively far distance 
(191 m) and moves towards the center of the FOV until around 35 m at 
which point it moves out towards the edge of the FOV again (see Figure 
7). In comparison, in the SAE test run, at 155 meters (the start of the 
SAE test), Fixture 1 is near the center of the FOV at approximately 2.5 
degrees left, and as the test vehicle approaches the fixture the 
fixture moves out to the edge of the field of view.
    As another example, this time on a right curve with a radius of 230 
m, the fixture enters the FOV at the right edge of the field of view 
(25R) at about 205 m and moves towards and then across the center of 
the FOV. In comparison, in the SAE test, at 155 meters (the start of 
the SAE test), Fixture 3 is near the center of the FOV (at about 3 
degrees right), and as the test vehicle approaches the fixture the 
fixture trajectory moves out to the right edge of the field of view. 
The SAE test evaluates rather large angles to the right of the beam 
pattern, almost entirely to the right of where the NHTSA test method 
examines the beam pattern performance. The agency believes this to be 
unusual in reality, particularly for oncoming encounters.
    Because the SAE test does not accurately replicate the fixture 
trajectory, it does not test how the system will need to actually 
function. For example, one way to ``optimize'' optical recognition is 
to focus on where an object is most likely to appear. The speed and 
accuracy of image recognition software can be increased without 
increasing computing power if systems are trained to look in smaller 
portions of an image for key elements, as opposed to looking at the 
entire image continuously. Including test scenarios with actual curves 
will discourage manufacturers from taking ``shortcuts'' and designing 
ADB systems that do not react until the stimulus vehicle enters narrow 
angles within the camera's FOV.
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[[Page 9938]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.007

    Second, the SAE approach does not accurately replicate real curves 
with respect to the speed at which the fixture traces its trajectory. 
On an actual curve, the fixture travels horizontally across the FOV 
relatively quickly at longer distances than on a simulated curve. For 
instance, a left curve requires the headlamp to start shading on the 
left side of the pattern, quickly move to the right; briefly hold the 
shade near the middle; and very quickly move the shade back to the far 
left. A simulated curve, on the other hand, simply necessitates that 
the system starts shading the middle of the pattern; hold nearly that 
same angle; and then quickly move the shade either left or right at 
closer distances. Including actual curved-path scenarios will 
discourage manufacturers from very accurately following the straight 
path pattern but less accurately following the paths required for real-
world curves; it should therefore result in better real-world 
performance than would the SAE J3069 fixture placements.
    NHTSA's recent testing confirmed that the SAE scenarios do not 
accurately model how an ADB system will perform on an actual curve. For 
example, the agency tested ADB system performance on an 85 m left curve 
as well as the most closely analogous SAE scenario, with the fixture 
place in Fixture Position 1. (Fixture Position 1 is the closest 
analogue to this scenario because it is the leftmost fixture position 
in the SAE test.) See Figure 8. On the actual curve, the system did not 
recognize and adjust to the fixture until 45 m. On the most closely 
analogous SAE scenario (Fixture Position 1), the system was able to 
continuously track the fixture from 150 m away. Even when the agency 
repeated the same SAE scenario at a much higher speed of 61 mph, the 
SAE test did not challenge the system's image recognition in an 
observable way. This shows that an ADB system's initial image 
recognition capability is not challenged by the SAE test as it is in a 
more realistic curve test, meaning that NHTSA is less confident that 
the SAE test would result in an equivalent level of safety as the 
actual-curve test that NHTSA is finalizing. The practical implications 
of this is that glare will not be sufficiently controlled by the SAE 
test compared to the actual-curve test adopted in this final rule.

[[Page 9939]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.008

    As another example, SAE J3069 does include a sudden appearance test 
(using the oncoming and preceding motorcycle fixtures) in which the 
fixture lamps are activated when the test vehicle is between 155 m and 
100 m from the fixture. The agency found, however, that this also does 
not realistically simulate a curve. See Figure 9. On an 85 m left curve 
at 26 mph, the ADB system recognized the final rule oncoming motorcycle 
fixture at 20 m. On the SAE sudden appearance scenario, in contrast, 
the ADB system performed better, activating a shaded area at 70 m. 
Additional comparative data from the final rule scenarios and the SAE 
test scenarios are presented and discussed in Section VIII.C.8, Test 
Scenarios.
[GRAPHIC] [TIFF OMITTED] TR22FE22.009

BILLING CODE 4910-59-C
    NHTSA disagrees with SAE's comment to the extent that it suggests 
that a final rule incorporating actual curves might not be objective or 
repeatable. The final rule sets out a rational test procedure that 
yields a clear answer based upon readings obtained from measuring 
instruments and is capable of producing identical results when test 
conditions are exactly duplicated.\87\ The final rule specifies the 
specific scenarios NHTSA may test, including ranges and values for key

[[Page 9940]]

testing parameters (e.g., differing radii of curvature), and specific 
numeric limits for the maximum allowable illuminance at certain 
distances; there is thus no ambiguity with respect to the parameter 
values NHTSA may select in compliance testing. Moreover, NHTSA has 
conducted a repeatability analysis and has concluded that the finalized 
test scenarios and procedures are repeatable (see Section VIII.C.11, 
Repeatability).
---------------------------------------------------------------------------

    \87\ See, e.g., Chrysler Corp. v. Dept. of Transp., 472 F.2d 
659, 676 (6th Cir. 1972).
---------------------------------------------------------------------------

    NHTSA did, however, agree that some of the proposed curve scenarios 
were too stringent. With respect to oncoming glare scenarios, the final 
rule eliminates the short right curve scenario and reduces the 
distances at which glare on the medium and large right curves and the 
short and medium left curves is evaluated. With respect to preceding 
glare scenarios, the final rule includes a straight-path scenario and a 
medium left curve scenario. The specifications for the radii of 
curvature have also been slightly modified. These modifications and 
other choices are explained in more detail later in the preamble.
    In general, NHTSA selected the final scenarios based on three 
criteria:
    The scenario represents commonly-encountered roadway geometries and 
vehicle interactions. To ensure that ADB systems operate safely, the 
final scenarios should include at least the most common road geometries 
and vehicle interactions. Because the adaptive driving beam is intended 
for distance illumination at speeds at which the lower beam does not 
provide adequate illumination--typically above 20 mph--these geometries 
and interactions should be those common at these speeds.\88\
---------------------------------------------------------------------------

    \88\ See NPRM, pp. 51787-51788.
---------------------------------------------------------------------------

    A compliant lower beam could pass the scenario. We also generally 
chose scenarios such that a compliant lower beam would be able to pass 
the scenario. There were several reasons for this. First, this (in 
conjunction with the requirement that areas of reduced intensity meet 
the corresponding lower beam laboratory photometric requirements) 
ensures that an area of reduced intensity, up to and including a full 
lower beam, will meet the same level of safety (with respect to both 
visibility and glare prevention) as current lower beams certified to 
FMVSS No. 108. Second, this is consistent with the concept for the 
proposal: Extending the current laboratory-based lower beam photometric 
requirements (specifically, the photometric maxima regulating oncoming 
and preceding glare) for use in a vehicle-level test to evaluate the 
ability of an ADB system to minimize glare (both oncoming and 
preceding).\89\ Because the track test was intended as an extension of 
the current laboratory photometric requirements, the track test 
requirements should (generally) be such that a lower beam (or area of 
reduced intensity) that complies with the current laboratory 
photometric requirements will also comply with the track test 
requirements.
---------------------------------------------------------------------------

    \89\ See NPRM, pp. 51770, 51773.
---------------------------------------------------------------------------

    The scenario is generally within the capabilities of robustly-
designed internationally-available ADB systems. As noted above, the 
field of view for current ADB systems is typically 25 degrees to the 
left and right of the camera, and, as explained below,\90\ ADB 
adaptation time--the time it takes an ADB system to recognize a 
stimulus (once the stimulus is within the camera's field of view) and 
dim the beam to a level that falls within the applicable glare limit--
is generally about 1 second. Therefore, NHTSA generally chose scenarios 
such that it would be possible for an ADB system with such field of 
view and response capabilities to pass the scenario. This is not to say 
that all current ADB systems would necessarily be able to pass all the 
final scenarios without any modifications. However, the agency intended 
to select scenarios that were generally within the reach of current 
technology (perhaps necessitating some additional improvements, 
adjustments, or optimizations, depending on the ADB technology), to 
facilitate timely deployment of ADB systems. NHTSA also recognized that 
these systems have been in use in foreign markets for several years 
with few, if any, apparent safety issues.\91\ We discuss and apply 
these criteria in more detail in Section VIII.C.8, Test Scenarios.
---------------------------------------------------------------------------

    \90\ See Section VIII.C.5, ADB Adaptation Time.
    \91\ The fact that the final rule does not include all the 
proposed scenarios does not mean that NHTSA has concluded that only 
a relatively small set of narrowly circumscribed scenarios is 
permissible in an FMVSS. In this case, NHTSA has concluded that 
adopting a smaller set of test scenarios appropriately addresses 
both the need for safety (including facilitating the timely 
deployment of ADB systems) and practicability. This also does not 
imply that FMVSS requirements must be tailored to the capabilities 
of currently existing systems. See, e.g., Chrysler Corp. v. Dept. of 
Transp., 472 F.2d 659, 673 (6th Cir. 1972) (``[T]he Agency is 
empowered to issue safety standards which require improvements in 
existing technology or which require the development of new 
technology, and it is not limited to issuing standards based solely 
on devices already fully developed.'').
---------------------------------------------------------------------------

4. Maximum Illuminance Criteria (Glare Limits)
    The NPRM included a set of photometric maxima to evaluate an ADB 
system's ability to minimize glare in the track test (glare limits). 
Because the current photometric test points from which the proposed 
glare limits were derived are maxima, the agency proposed applying the 
derived glare limits as maxima, so that any measured exceedance of an 
applicable glare limit (except for momentary spikes) would be used to 
determine compliance. The NPRM also extended the standard's ``design to 
conform'' language to the proposed requirements, including the glare 
limits.\92\ The NPRM also summarized the basis for the glare limits 
(the full explanation for the derivation is given in the Feasibility 
Study).
---------------------------------------------------------------------------

    \92\ As we explained in the NPRM, the proposal extended the 
standard's longstanding ``design to conform'' language to the 
proposed requirements because the concept of the rulemaking was to 
extend the current headlamp requirements to ADB systems. We 
therefore considered the continued appropriateness of ``design to 
conform'' to be outside the scope of this rulemaking. However, this 
extension in no way limits NHTSA's ability to revisit the issue of 
design to conform in the future. Furthermore, if NHTSA were to 
reconsider the design to conform language, it might not come to the 
same conclusion it did when it originally adopted that language. As 
we explained in the NPRM, NHTSA adopted the ``design to conform'' 
language when the standard was introduced in 1967 because it 
accepted industry's contemporaneous representation that vehicle 
lamps could not be manufactured to meet every single test point 
without a substantial cost penalty unjustified by safety. We further 
explained that, because lighting equipment design, technology, and 
manufacturing have evolved and advanced since the late 1960's, NHTSA 
might not come to the same conclusion were it to revisit this issue.
---------------------------------------------------------------------------

    The NPRM explained that the proposed glare limits deviate from SAE 
J3069 in a few respects. First, two of the glare limits differ 
slightly. At 60 m, SAE J3069 uses glare limits of 0.7 lux (oncoming) 
and 8.9 lux (preceding) compared to the proposed 0.6 lux and 4.0 lux. 
Second, SAE J3069 applies to a narrower range of distances (30 m-155 m) 
than the proposed glare limits (15 m-220 m). Third, SAE J3069 applies 
the glare limits only at the endpoints of the measurement ranges (i.e., 
155 m, 120 m, 60 m, and 30 m), while the NPRM applied the glare limits 
throughout the entire measurement range. The proposal explained the 
reasons for these deviations from SAE J3069.
Comments
    A few commenters (AAA, Consumer Reports, and Zoox) supported the 
glare limits as proposed. Intertek agreed that the baseline glare limit 
requirements should extend to the full distance ranges rather than only 
at the four individual distances specified in SAE J3069. Several 
commenters, however, contended that the glare limits were too stringent 
and suggested a variety of modifications.

[[Page 9941]]

    SAE, Global, Ford, Toyota, the Alliance, and Auto Innovators 
commented that the proposed glare limits were conservative and that 
using absolute measurements of discomfort glare (the aspect of glare 
that is painful or annoying, as opposed to the aspect of glare that 
limits the ability to see other objects) is unreasonable and not 
practicable. They recommended the final rule include reasonable 
allowances for an ADB system to momentarily exceed the glare limits, 
especially given the large number of proposed test scenarios. They also 
stated that the proposed glare limits are well below the illuminance 
provided by contemporary lower beams, including Insurance Institute for 
Highway Safety (IIHS) top-rated lower beams for MY 2017 vehicles, 
especially on curves. As noted earlier, SAE provided analyses and 
graphs based on IIHS data on lower beam performance on different road 
geometries, from straight roads to left and right curves of various 
radii.\93\
---------------------------------------------------------------------------

    \93\ Auto Innovators also supplied an apparently somewhat 
similar analysis of IIHS data (on pp. 12-13 of its comment). 
However, the comment did not identify the geometry of the road (the 
orientation of the headlamps to the photometer) for the 
measurements, so the agency is unable to evaluate this submission. 
In any case, NHTSA addresses this issue using the IIHS data 
submitted by SAE and the agency's own testing of lower beams to the 
scenarios included in the final rule.
---------------------------------------------------------------------------

    For those reasons, SAE, the Alliance, and Toyota argued that NHTSA 
should evaluate the ratio of the ADB to lower beam illuminance. SAE 
noted that this procedure is specified in SAE J3069, which requires the 
measured illuminance to be no more than 25% above the measured lower 
beam illuminance. SAE further stated that NHTSA's 2015 ADB Test Report 
used a similar procedure, and that an UMTRI report found that 25% was 
an acceptable maximum limit above the lower beam.\94\ Toyota commented 
that following SAE J3069 in this respect would facilitate ADB 
deployment across a wider range of vehicles.\95\ Auto Innovators also 
argued for a similar 25% allowance (discussed below).
---------------------------------------------------------------------------

    \94\ DOT HS 808 209, Sept. 1994.
    \95\ SAE and other commenters also argued that comparing the 
ratio of the illuminance from the adaptive beam to the lower beam 
would also compensate for unaccounted for test variability such as 
dips and bumps in the road. This is discussed below in Section 
VIII.C.10.d, Allowance for Momentary Glare Exceedances.
---------------------------------------------------------------------------

    A few commenters expressed interest in the final rule accounting 
for glare dosage. Toyota commented that there is no clear evidence that 
exceeding the maximum illuminance for longer than 0.1 second leads to a 
safety hazard any greater than what occurs with existing headlighting 
systems on U.S. roads today. Mobileye similarly commented that a 
distinction needs to be introduced between glaring that may cause 
discomfort to other drivers and glaring which may pose a safety risk. 
It asserted that, while the NPRM assumes that any glare exceedances for 
more than 0.1 seconds are not acceptable, drivers commonly use 
intentional, limited glaring as a signaling mechanism to other drivers. 
Accordingly, Mobileye suggested allowing glare exceedances longer than 
0.1 seconds. AAA commented that the final rule should not permit glare 
exceedances lasting longer than 1 second because its research showed 
that glare from an oncoming vehicle lasting approximately 1 second was 
rated as highly distracting. Intertek believed that proposed 0.1 second 
allowance would account for the majority of the issues related to glare 
dosage, exposure, or perceptibility because any longer exceedance is 
detectable by the human eye. Auto Innovators also asserted that the 
final rule should account for glare dosage. (This is discussed further 
below.)
    NHTSA received a few comments about the proposed measurement 
distances. Intertek commented that regulating glare for distances 
extending out to 220 m is unnecessary because the angular size and 
position of oncoming headlamps at distances greater than 155 m mitigate 
any harmful effects of glare. Intertek commented that testing out to 
220 m creates additional complexity and testing costs. In contrast, AAA 
suggested regulating glare beyond 220 m. They noted that European 
specifications require camera recognition and reaction at distances of 
400 meters (1,312 feet), and that intensity limits could be increased 
from the current maximum of 150,000 cd to the European maximum of 
430,000 cd if ADB systems are effective at this distance. SAE commented 
that the proposed requirements for preceding glare are too stringent, 
given the detection distance (120 m vs. 100 for the ECE) and the 
minimum photometric requirements for rear lamps (2 cd vs. 4 cd for the 
ECE).
    Valeo commented that the proposed maximum illuminance requirements 
would result in wildly varying light output, especially compared to the 
current ECE requirements, which result in a much more constant and 
consistent light intensity. Valeo also suggested that the final rule 
clarify that the requirements apply to the entire ADB system (both 
left-hand and right-hand headlamps).
    Intertek suggested measuring luminance \96\ from the ADB system 
headlamps rather than illuminance at the test fixture would provide 
several benefits, including: The data collected from the test would 
have a record which is very closely matched, and can be perceived and 
analyzed in much the same way as what an actual driver of the stimulus 
vehicle would have experienced; the recorded data can be viewed as a 
map of luminous intensity (candela) emitted from the test vehicle, 
which would be directly comparable to the existing photometry 
requirements, and can be plotted as a function of time or approach 
distance; over time, if this data is collected carefully and attention 
is paid to those scenarios in which the driver of the stimulus vehicle 
feels glared, a better quantitative baseline for and understanding of 
glare can be established.
---------------------------------------------------------------------------

    \96\ ``Luminance'' refers to the luminous intensity produced by 
a light source in a particular direction per solid angle, while, as 
noted earlier, ``illuminance'' refers to the amount of light falling 
on a surface. The unit of measurement for luminance is candela, 
while the unit of measurement for illuminance is lux. A measure of 
luminous intensity in candela can be converted to a lux equivalent 
(and vice versa), given a specified distance.
---------------------------------------------------------------------------

    Auto Innovators stated that NHTSA should adopt a modified version 
of the IIHS right-curve glare exposure criteria for all oncoming 
scenarios.\97\ See Table 5. Auto Innovators contended that this would 
be appropriate because the IIHS glare limits are intended to provide 
consumers with a relative assessment of headlamp performance and it is 
possible for a vehicle to drastically exceed the glare criteria in the 
IIHS test and still comply with FMVSS No. 108; the IIHS protocol allows 
exceedances in the form of cumulative exposures as opposed to hard 
pass/fail limit at a single point in time, resulting in a series of 
demerits (based on the percentage over the limit) for which it is 
possible for a vehicle to achieve a ``Good'' rating while still 
offering small amounts of glare. Auto Innovators recommended adopting a 
similar method for establishing an allowable time exceedance for each 
test range.
---------------------------------------------------------------------------

    \97\ Insurance Institute for Highway Safety. Headlight Test and 
Rating Protocol, Version III (July 2018); Rationale and Supporting 
Work for Headlight Test and Rating Protocol. (August 2015).

Table 5--Auto Innovators' Modified Maximum Illuminance Criteria Based on
                              IIHS Protocol
------------------------------------------------------------------------
                                                             Illuminance
                       Distance (m)                          limit (lx)
------------------------------------------------------------------------
30 to 59.9................................................             6

[[Page 9942]]

 
60 to 119.9...............................................           3.4
120 to 220................................................             1
------------------------------------------------------------------------

    Auto Innovators gave a few different arguments for adopting its 
proposed glare limits. First, it claimed that the IIHS glare limits 
better reflect modern headlighting systems. It noted that the proposed 
glare limits are based, in part, on headlamps typical of the 1997 model 
year, whereas the IIHS protocol is based on contemporary headlighting 
systems. Next, Auto Innovators contended that the IIHS protocol 
accounts for research indicating that the harmful effects of glare 
depend on both peak illuminance and overall dosage of glare exposure. 
Finally, Auto Innovators contended that the IIHS methodology accounts 
for glare effects due to incidence angle whereas the Feasibility Study 
does not. Auto Innovators recommended eliminating the 15-29.9 m 
measurement range (for both oncoming and preceding scenarios) because 
its test data showed not only that the least amount of failures 
occurred in this interval but that the exceedance durations for all 
failures in this range were 1.0 second or less.\98\
---------------------------------------------------------------------------

    \98\ Auto Innovators also argues that glare exceedances at these 
short distances may be caused by swiveling of the headlamps. While 
this only applies to swiveling beam ADB systems, Auto Innovators 
believes that any safety standard should remain technology neutral.
---------------------------------------------------------------------------

    In addition to recommending NHTSA adopt its suggested glare limits, 
Auto Innovators recommended that the final rule require passage of a 
percentage of averaged individual illuminance readings to achieve 
compliance instead of looking to the maximum recorded illuminance in 
each measurement range. Specifically, Auto Innovators appeared to 
suggest that NHTSA perform three test runs for each scenario and 
average the maximum illuminance in each measurement range recorded for 
each scenario. Then, it asks that NHTSA allow up to 15% of the averaged 
illuminance readings to exceed its recommended glare limits by up to 
25%. Auto Innovators cited the same UMTRI and NHTSA reports referenced 
earlier, as well as three inconsequentiality petition grants as the 
basis for the 25% allowance.\99\ Auto Innovators commented that the 15% 
allowance comes from the turn signal test requirements in S14.9.3 of 
FMVSS No. 108. It contended that this amount of performance variation 
is consistent with the challenges of outdoor dynamic testing where 
little previous experience exists, especially compared to the highly-
controlled laboratory photometric testing that has previously been 
used. Auto Innovators commented that it would be difficult not to 
attribute failures of illuminance readings to variances that could 
appear in the novel and unique aspects of the test procedure, rather 
than to quality control issues, particularly where the time and 
complexity of the testing preclude conducting it on multiple ADB-
equipped vehicles. It also asserted that this approach is consistent 
with the standard's design to conform language. Mobileye similarly 
suggested specifying a pass/fail ratio for the measured illuminance 
values in each specified measurement interval.
---------------------------------------------------------------------------

    \99\ 85 FR 39678 (July 1, 2020) (grant of petition for 
inconsequential noncompliance for side marker lamp below photometric 
minima); 85 FR 39679 (July 1, 2020) (grant of petition for 
inconsequential noncompliance for rear reflectors below minima); 55 
FR 37601 (Sept. 12, 1990) (grant of petition for inconsequential 
noncompliance for taillamp exceeding maxima).
---------------------------------------------------------------------------

Agency response
    NHTSA agrees with the commenters that the proposed glare limits 
were overly stringent at some geometries and measurement distances in 
that a current, FMVSS No. 108-compliant lower beam would not have 
complied with some of these requirements. The agency has therefore 
modified the proposal by deleting the short right curve scenario and 
modifying measurement distances for other specified radii of curvature. 
NHTSA believes that these modifications reasonably ensure that a lower 
beam that complies with the current FMVSS No. 108 photometry 
requirements would be within the glare limits as applied in the 
specified measurement ranges in each of the final scenarios. This is 
discussed in further detail in Section VIII.C.8, Test Scenarios.\100\
---------------------------------------------------------------------------

    \100\ NHTSA anticipates that ADB systems could provide better 
glare protection than current lower beams if dynamic vertical aim is 
incorporated into the systems. Current lower beams will produce 
glare on hills and undulating roads. Because of the nature of the 
adaptive beam's area of unreduced intensity, it does not have the 
same sensitivity to aim as a lower beam with respect to seeing 
distance. For example, an ADB pattern could be aimed down more than 
a lower beam (preventing glare even when the vehicle pitches) while 
still providing appropriate seeing distance in directions where 
glare protection is not required. However, the agency decided not to 
require additional glare protection performance from ADB systems 
beyond that currently produced by lower beams (except on right 
curves) and anticipates aiming strategies might be incorporated into 
ADB systems in order to maintain reasonable compliance margins.
---------------------------------------------------------------------------

    NHTSA disagrees with some commenters' suggestions to follow SAE 
J3069 and only consider an ADB system as not complying with the glare 
limits if the measured ADB illuminance exceeds 25% of lower beam 
illuminance. The final rule differs from the proposal by eliminating 
overly stringent scenarios and providing additional adjustments to 
account for testing variability, including data filtering procedures 
and an adjustment for vehicle pitch, in addition to the proposed 
allowance for momentary glare exceedances. The agency believes that 
these modifications obviate the need for any further glare limit 
allowances. While more relaxed test requirements might facilitate ADB 
deployment, they would not ensure that ADB systems function properly. 
We believe that the final requirements and test procedures strike a 
reasonable balance between visibility and glare prevention.
    Neither the UMTRI report nor the comments relating to the NHTSA 
research cited by the commenters are persuasive. The UMTRI report 
concerned the evaluation of inconsequentiality petitions, not the 
appropriate magnitude of the lower beam maxima, which is the relevant 
issue when considering the appropriate level for the glare limits.\101\ 
As explained in the NPRM, the proposed glare limits were based on FMVSS 
No. 108's longstanding Table XIX photometric maxima. While the 2015 ADB 
Test Report did examine how close the observed ADB illuminance values 
were to the relevant glare limit, including an analysis of the effect 
on the results of increasing the glare limits by up to 25%,\102\ the 
analysis did not concern ``just noticeable differences'' or state or 
imply that exceedances of up to 125% of the relevant glare limit were 
inconsequential. Instead, the purpose of this analysis was to ``see 
whether increasing the glare limit would have changed an exceeding 
result to a non-exceeding result.'' \103\ The 2015 ADB Test Report also 
examined the ratio of ADB illuminance to lower beam illuminance. This 
analysis was intended to evaluate ADB functionality, not as a means of 
evaluating ADB compliance. This was particularly useful because some of 
the lower beam headlighting systems tested in the 2015 study were not 
designed to meet the requirements

[[Page 9943]]

of FMVSS No.108. Using a ratio allowed for the comparison of basic ADB 
functionality against the lower beam regardless of the photometric 
standard to which the lower beam was designed.\104\
---------------------------------------------------------------------------

    \101\ See DOT HS 808 209, Sept. 1994, p. 9 (concluding that 
``using 25% as a criterion for inconsequential noncompliance'' is 
appropriate for lower-beam headlamps) (emphasis added).
    \102\ 2015 ADB Test Report, p. 133.
    \103\ Id.
    \104\ Although commenters did not suggest it, we also decided 
not to adopt an adjustment such that if ADB illuminance exceeds an 
applicable glare limit, the exceedance would be considered a 
noncompliance only if the ADB illuminance exceeded the lower beam 
illuminance (i.e., without a 25% cushion). The reasons for this are 
the same as the reasons for not adopting the commenters' 
recommendations.
---------------------------------------------------------------------------

    Regarding the distances at which to regulate glare, regulating 
oncoming glare out to 220 m is appropriate. As the Feasibility Study 
explained, at greater distances a smaller glare limit is appropriate 
because, at greater distances, ``the glare source will be seen by the 
oncoming driver at a smaller angle.'' \105\ NHTSA was able to test the 
final scenarios out to this distance (where applicable) and did not 
encounter any testing difficulties related to this distance. On the 
other hand, NHTSA did not develop testing scenarios for oncoming glare 
at distances greater than 220 m, and so is not prepared to test beyond 
that distance. The reasons for regulating oncoming glare out to 220 m 
are discussed in greater detail in Section VIII.D.4, Requirements for 
area of unreduced intensity. NHTSA does agree with SAE that it is more 
appropriate to test preceding glare only out to 100 m, and not the 
proposed 120 m. The reasons for this are discussed in more detail in 
Section VIII.C.8.g, Scenario 7: Preceding Straight.
---------------------------------------------------------------------------

    \105\ Feasibility Study, p. 23.
---------------------------------------------------------------------------

    The agency disagrees with Valeo's assertion that specifying the 
glare limits as a stepwise (discontinuous) function of distance will 
result in dramatic fluctuations in light output. The glare limits are 
photometric maxima, not design requirements, and there is no reason to 
think that manufacturers will design headlamps that suddenly increase 
or decrease in brightness for reasons unrelated to road conditions. 
Moreover, the laboratory requirements that reference the Table XIX 
photometric maximum intensity limits preclude manufacturers from 
producing areas of reduced intensity that vary as Valeo would suggest. 
In fact, the output limits specified in Table XIX require lower beam 
intensities (which is what the agency requires the ADB systems to 
produce in the area of reduced intensity) well below those calculated 
by Valeo at the further distances of the measurement subrange.
    While the final rule could have specified the glare limits as a 
continuous function of distance, this would have been more complicated. 
In any case, the stepwise specification is less stringent than 
specifying glare limits as a continuous function of the closing 
distance between the test vehicle and the test fixture. The glare 
limits for each of the four specified ranges was derived from the 
shortest distance in the range, and then applied to all the (further) 
distances in the range. As the Feasibility Study explained, however, 
the glare limits are derived to decrease as distance increases.\106\ 
Therefore, if the glare limits were specified as a continuous function 
of distance, they would decrease throughout the interval as distance 
increased. By specifying the glare limits as a stepwise function, the 
glare limits are higher at the further distances in the interval than 
they would have been if we specified them as a continuous function of 
distance. This has the benefit of simplicity. It also essentially gives 
manufacturers an additional margin for error than they would have had 
if we specified the limits as a continuous function of distance. The 
final rule has, however, incorporated Valeo's suggestion to clarify 
that the requirements apply to the entire ADB system.
---------------------------------------------------------------------------

    \106\ Id.
---------------------------------------------------------------------------

    Intertek makes an interesting suggestion for quantifying perceived 
glare. However, based on the agency's stated goals of minimizing the 
cost impact of the regulation and providing a pathway for introduction 
of ADB systems for use on U.S. roadways as quickly as possible, the 
final rule does not adopt Intertek's suggestion. To do so would require 
additional research to inform the agency on how such changes would 
affect the glare and photometry limits specified, as well as any costs 
associated with requiring the agency and the industry to switch from 
test methods designed around measuring illuminance at the test vehicle 
to measuring luminance. The agency simply has no data to support such a 
change at this time.
    NHTSA understands Auto Innovators' suggestion to adopt the IIHS 
glare limits as related to their general argument that the proposed 
glare limits and test scenarios were too stringent. As explained 
earlier, NHTSA agreed with this point to some extent and modified the 
measurement distances, test scenarios, and allowances accordingly. 
However, the agency does not adopt Auto Innovators' glare limits for 
two reasons.
    First, the glare limits suggested by Auto Innovators are three 
times the proposed limits, which are based on the current photometry 
requirements. The intent of this rulemaking is to permit ADB without 
increasing glare from levels currently on the road. NHTSA's testing 
showed that Auto Innovators' suggested limits do not represent glare 
produced by compliant lower beams under the controlled driving 
situations that are part of the ADB test, particularly for straight and 
left curve scenarios. For the left curve and straight path scenarios, 
testing of the Fusion and Volvo demonstrated that a considerable margin 
is achieved with the proposed glare limits.\107\ See Table 6. These 
same types of margins are present throughout our lower beam testing. 
This confirms that these limits provide a boundary to protect the 
public from additional glare beyond what is currently experienced on 
the roads today. See also the discussions of lower beam performance on 
various scenarios in Section VIII.C.8, Test Scenarios. The commenter's 
suggested limits would significantly increase that boundary and permit 
substantially higher glare on the roads.
---------------------------------------------------------------------------

    \107\ The Fusion used had not been rated by IIHS. The Volvo was 
rated ``acceptable'' by IIHS.

                        Table 6--Lower Beam Illuminance Margin for Proposed Glare Limits
----------------------------------------------------------------------------------------------------------------
                           Range  (m)                               Glare limit     Max illum.      Margin  (%)
----------------------------------------------------------------------------------------------------------------
                                        Volvo 210 m left curve at 42 mph
----------------------------------------------------------------------------------------------------------------
150.0-120.0.....................................................             0.3           0.051              83
119.9-60.0......................................................             0.6           0.158              74
59.9-30.0.......................................................             1.8           0.788              56
29.9-15.0.......................................................             3.1           2.118              32
----------------------------------------------------------------------------------------------------------------

[[Page 9944]]

 
                                       Fusion 400 m right curve at 54 mph
----------------------------------------------------------------------------------------------------------------
70.0-60.0.......................................................             0.6           0.415              31
59.9-30.0.......................................................             1.8           0.933              48
29.9-15.0.......................................................             3.1           1.394              55
----------------------------------------------------------------------------------------------------------------

    Second, the agency believes the proposed oncoming glare limits 
(which are derived from the Table XIX left side photometric maxima) are 
most appropriate for any oncoming scenario--including right curves--
because they were derived from limits designed specifically for 
oncoming traffic (which in the United States are typically to the left, 
except on right curves). Auto Innovators' suggested limits may be 
appropriate for the right side of lower beams where the compromise 
between seeing distance and glare places greater value on seeing toward 
the right side. This is appropriate for a static beam pattern that 
limits glare in all horizontal directions no matter where the other 
road user is located. If one thinks of oncoming interactions as being 
oriented in terms of either straight, left curve, or right curve, two 
of these three (straight and left curve) have the other vehicle toward 
the left of the subject vehicle's headlamps. So, for those two 
situations, it is better to allow more potential glare to the right 
side of the road (where other road users are less likely to be) in 
order to provide some seeing light in that direction. For the remaining 
right curve situation, the beam is still limited, but less so, and some 
glare is expected to account for better seeing distance toward the 
right for the other two situations. No such compromise needs to be 
applied for ADB. The ADB pattern creates a reduced illumination area to 
the left when the other vehicle is to the left and an unreduced area to 
the right. When the other vehicle is toward the right, the same 
protection can now be applied to those encounters as to the straight 
and left, without sacrificing seeing distance. As such, the agency is 
using the glare limits derived for the left side oncoming curve 
scenario for the right curve scenario.
    The agency acknowledges the relationship between dosage (the 
product of illuminance and duration) and the disabling effects of 
glare. For glare control, the IIHS headlamp rating procedure uses a 
derivative of dosage (distance for which a limited illuminance is 
exceeded). However, the quantified crash risks associated with 
exceeding these limits is not clear. Research the agency conducted in 
2008 began to explore this relationship, noting that ``specification of 
the integrated (summed) values throughout the segment would be more 
likely to provide control for glare recovery, but would involve 
headlamp light measurement procedures that are more complex than those 
currently used to determine if a headlamp meets the FMVSS 108 
requirements.'' \108\ Until this final rule, the basic structure of the 
headlighting regulation (goniometer--photometry) did not provide a 
foundation for which glare dosage could be readily measured and 
regulated. As such, the agency has not focused its research in this 
area. While NHTSA agrees that a qualitative relationship exists, the 
agency has not established, and does not know of, a quantified 
relationship between glare dosage and crash risk.
---------------------------------------------------------------------------

    \108\ DOT HS 811 043 Nighttime Glare and Driving Performance: 
Research Findings, 2008.
---------------------------------------------------------------------------

    Another limitation of IIHS's method is that it considers all glare 
doses equal (except for distances between 5 m and 10 m). The impacts of 
glare, however, are also related to the angle between the glare source 
and the line of sight of the viewer. The glance pattern of drivers in 
nighttime glare situations is not well understood, as some drivers may 
be inclined to look toward the glare source effectively causing the 
angle between the line of sight and the glare source to be zero.\109\ 
To the extent that a driver follows driver's education recommendations 
and does not look at the glare source, glare doses in roadway 
interactions are not equally impactful at all distances, as the angle 
between the glare source and the line of sight is smaller at far 
distances. Such an effect is reflected in the current photometric 
tables and was, in fact, taken into account in the glare limits 
derivation in the Feasibility Study, in that the glare limits are 
smaller at greater distances.\110\ NHTSA therefore disagrees with Auto 
Innovators that the IIHS study accounts for glare effects due to 
incidence angle.\111\
---------------------------------------------------------------------------

    \109\ 2007 Report to Congress, pg. iv.
    \110\ See Feasibility Study, p. 23.
    \111\ In addition, we note that the negative impacts of glare 
are not limited to disabling glare, but are also related to the 
annoyance and even painful experience of other roadway users. 
NHTSA's 2008 research concluded that ``the peak illuminance, rather 
than the dosage, was the primary factor associated with rated 
discomfort.'' DOT HS 811 043 Nighttime Glare and Driving 
Performance: Research Findings, 2008.
---------------------------------------------------------------------------

    NHTSA is therefore finalizing the glare limits as proposed. Future 
development of glare dosage as full vehicle dynamic testing for 
headlighting systems continues to mature is of interest to the agency.
    With respect to Auto Innovators' comments regarding specifying an 
allowance of 25% over the glare limits, we disagree with this for the 
reasons given above regarding the evaluation of the ratio of adaptive 
driving beam to lower beam illuminance. NHTSA also does not find the 
cited inconsequentiality petition grants to be persuasive because they 
did not concern headlamps, and, except for one of the petitions, did 
not concern glare. The agency was also not persuaded by the suggestions 
by Auto Innovators and Mobileye to adopt a pass/fail ratio or to 
average a number of test runs in order to mitigate test-related 
variability. Such procedures, while occasionally specified in an FMVSS, 
would be unusual. In any case, we do not believe this is necessary here 
for two reasons. First, we believe the final test procedure already has 
sufficient allowances for test-related variability (an allowance for 
momentary glare exceedances, a vehicle pitch adjustment, and the 
application of a low-pass filter with a cutoff frequency of 35 
Hz).\112\ Second, we conducted a repeatability analysis and found the 
final test procedure to be repeatable.\113\
---------------------------------------------------------------------------

    \112\ See Section VIII.C.10, Data Acquisition and Measurement.
    \113\ See Section VIII.C.11, Repeatability.
---------------------------------------------------------------------------

5. ADB Adaptation Time
    The NPRM included a 0.1 second or 1 m magnitude allowance for 
momentary glare exceedances. This was intended to account for 
variations in illumination due not to the ADB system but to 
uncontrolled or uncontrollable

[[Page 9945]]

testing variables. This differs from an allowance for an adaptation 
time, which would account for the operation of the ADB system--
specifically, the time it takes an ADB system to recognize a stimulus 
(once the stimulus is within the camera's field of view) and respond by 
dimming the beam, switching from an area of unreduced intensity to an 
area of reduced intensity. SAE J3069 specifies a 2.5 second maximum ADB 
adaptation time during the sudden appearance test drive. (The NPRM did 
not include a ``sudden appearance'' scenario because the system's 
ability to respond quickly is exercised by the shorter-radii curve 
scenarios.) The NPRM did not propose a time limit within which an ADB 
system would be required to respond to a stimulus, but sought comment 
on whether one should be included in the regulation.
Comments
    Some commenters interpreted the 0.1 second allowance for momentary 
glare exceedances as an adaptation time allowance.\114\ Mobileye, Ford, 
Honda, Volkswagen, and Auto Innovators contended that 0.1 second is not 
technically feasible and the final rule should specify a duration 
greater than 0.1 second because ADB systems need time to recognize the 
stimulus and modify the beam. Mobileye and Ford stated that without 
this, ADB systems would behave erratically, and Mobileye stated that it 
would result in many more false positives, leading to reduced 
visibility. Honda asserted that an insufficient time allowance would 
dis-incentivize the deployment of systems that operate over a wide 
range of conditions, and might especially be an issue on curves with a 
radius of 320-380 ft, on which an opposing vehicle will enter the ADB 
vehicle's field of view suddenly at a close distance. Honda suggested 
an allowance for an adaptation time sufficient to ensure that ADB 
systems have an appropriate amount of time to react to the sudden 
appearance of other vehicles or when environmental lighting changes 
dynamically when driving.
---------------------------------------------------------------------------

    \114\ The proposed allowance for momentary glare exceedances 
(intended to account for uncontrolled test-related variability) is 
discussed in Section VIII.C.10.d.
---------------------------------------------------------------------------

    Mobileye, Ford, Volkswagen, and Auto Innovators specifically 
supported the 2.5 second ``reaction time'' specified in SAE J3069. Ford 
commented that 2.5 seconds is reasonable based on its extensive 
experience with auto beam switching systems similar to ADB systems 
available internationally. Mobileye also noted that ECE R48 defines the 
minimal distance below which glaring is not allowed. Auto Innovators 
commented that its test data showed that a majority of exceedances were 
less than 2.0 seconds, with only a few exceedances over 2.5 seconds 
(limited to scenarios in which the stimulus vehicle was difficult to 
detect, such as the stationary motorcycle). Mobileye, Volkswagen, and 
Auto Innovators commented that 2.5 seconds would still be an 
improvement over human-driver reaction time.
    In contrast, AAA asserted that 2.5 seconds is inordinately long, 
and that the reaction time should be decreased to approximately 1 
second, based on its research which showed that glare from an oncoming 
vehicle lasting approximately 1 second was rated as highly distracting.
Agency Response
    Although the final rule does not specify an allowable ``adaptation 
time,'' the agency does agree that the final rule should generally take 
into account how long it takes a typical, well-designed ADB system to 
respond. Typical ADB adaptation times are a little over 1 second. An 
ADB test report published by SAE in 2016 reported a reaction time of 
about 1.1 seconds.\115\ NHTSA's testing showed comparable times, 
ranging from .56 seconds to 1.22 seconds when suddenly exposed to a 
stimulus.\116\ These reported adaptation times are much less than the 
2.5 seconds specified in SAE J3069.
---------------------------------------------------------------------------

    \115\ Assessment of Adaptive Driving Beam Photometric 
Performance (SAE 2016-01-1408), p. 3. This included the time it took 
for an experimenter to turn on the stimulus vehicle headlamps at a 
predetermined distance, so the actual system response time was 
shorter than this.
    \116\ 2015 ADB Test Report, p. 92.
---------------------------------------------------------------------------

    In addition, at the speeds the track tests are conducted, the test 
vehicles will cover a significant amount of the measurement distance 
within an adaptation time of 2.5 seconds (nearly 28 m at 25 mph, or 55 
m at 50 mph). For example, the SAE sudden appearance scenarios specify 
that the fixture lamp be suddenly exposed when the test vehicle is 
between 155 m and 100 m from the fixture. At 55 mph (24.6 m/s) the test 
vehicle will have traveled 61.5 m in 2.5 s. If the fixture lamps were 
activated at 100 m, this means that the test vehicle would be about 40 
m from the fixture by the time the 2.5 second allowance had elapsed. 
This would mean that only one illuminance value (at 30 m) would be 
evaluated by the SAE test. Similarly, in a real-world vehicle 
interaction, with two vehicles approaching each at 70 mph (31.3 m/s) 
each, if the ABD system takes 2.5 s to react, the two vehicles will 
have traveled 157 m before the ADB system reacts.
    After consideration of the studies and data discussed above, NHTSA 
believes that an ADB adaptation time of 2.5 seconds is exceedingly 
long. The final rule does not specify an adaptation time, however, 
because the final scenario parameters have generally been specified so 
that glare is not regulated until the fixture has been within the field 
of view of a typical ADB system (25 degrees to each side) long enough 
for the system to react (for example, in the small left curve scenario 
the fixture is within the camera's field of view for approximately 1.24 
s before the fixture enters the measurement distance range for that 
scenario). There are some exceptions to this. For some of the smaller-
radii curve scenarios, the final rule begins regulating glare at a 
distance at which a typical ADB system might not have had time to 
react. Even here, however, there is not a need for an adaptation time 
because a typical ADB system would not exceed the glare limits even at 
these distances. At these further distances, because there will be a 
relatively wide angle between the test vehicle headlamps and the test 
fixture, the upper beam illuminance at those angles (and distances) is 
not likely to exceed the applicable glare limit. There is also no 
apparent safety need for directing high illuminance at such wide 
angles. These points are covered in more detail in the sections below 
for the various test scenarios.
6. Test Fixture Specifications
    The NPRM identified test fixtures, including those specified in SAE 
J3069, as a regulatory alternative. The NPRM explained that SAE J3069 
specifies four test fixtures: An opposing car/truck fixture; an 
opposing motorcycle fixture; a preceding car/truck fixture; and a 
preceding motorcycle fixture. The NPRM explained that the SAE fixtures 
are fitted with lights intended to simulate actual vehicle lamps; the 
lamps are intended to represent reasonable worst-case for intensity and 
location and promote repeatability. For headlamp representations, the 
SAE standard specifies a lamp projecting 300 cd of white light in a 
specified manner and angle instead of actual headlamps. In addition to 
being intended to represent a reasonable worst-case condition, the SAE 
J3069 rationale also states 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

[[Page 9946]]

variability.'' \117\ For the taillamp representations, SAE J3069 
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 or the rearview/side mirrors would be 
located to measure illumination from the ADB test vehicle 
headlamps.\118\ The lamp and photometer locations are based on ``median 
location values provided by [the University of Michigan Transportation 
Research Institute].'' \119\
---------------------------------------------------------------------------

    \117\ SAE J3069, p. 4.
    \118\ SAE J3069 5.5.2 and Figures 1 and 2 (opposing vehicle 
fixture); 5.5.3 and Figures 3 and 4 (preceding vehicle fixture).
    \119\ SAE J3069, p. 3.
---------------------------------------------------------------------------

    The NPRM identified and sought comment on potential issues with the 
SAE J3069 fixture specifications, particularly whether using simulated 
lamps instead of actual vehicle lamps was sufficiently realistic. We 
stated that test fixtures may encourage an ADB system designed to 
ensure identification of test fixtures rather than actual vehicles, 
which might not adequately ensure that the system performs 
satisfactorily when faced with a wide range of real-world vehicles and, 
particularly, real-world vehicle lighting. We stated that we were not 
confident that the lamps specified in SAE J3069 represented a worst-
case scenario. As one example of this, we noted that 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. We therefore sought 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. We also noted, with 
respect to the concern raised in SAE J3069 that using actual lower beam 
headlamps on the opposing vehicle fixtures would lead to test 
variability, that in the real world an ADB system must be able to 
identify headlamps from many different types and models of vehicles; if 
an ADB system was so sensitive to actual headlamp gradients that those 
gradients affected ADB system performance, the variability would be 
attributable to the ADB system, not the test.
Comments
    The agency received several comments relating to test fixture 
specifications. While many manufacturers urged NHTSA to adopt SAE 
J3069,\120\ some commenters identified potential concerns with the SAE 
J3069 fixtures. Mobileye commented that the major drawback of SAE J3069 
is the use of synthetic stimulus light sources, which presents a 
challenge because in actual driving scenarios, the system is trained to 
ignore the types of synthetic light sources specified in SAE J3069 
because they are more likely to be lights from houses, driveways, or 
other non-vehicle sources. Mobileye pointed out that vehicle headlamps 
differ from the SAE fixtures in shape, power source (DC), and having a 
distinct non-uniform light dispersion pattern. Mobileye suggested that 
placing lamps on static fixtures will force an ADB system to react to 
light sources even when it positively recognizes them as not being part 
of a vehicle. Mobileye recommended that the fixture closely resemble a 
``uniform'' or ``standard'' vehicle with lamps representative of those 
approved by FMVSS No. 108 instead of the static fixtures specified in 
SAE J3069, so as not to force the ADB system to downgrade its real-life 
performance to comply with a synthetic test.\121\ Intertek commented 
that it is possible for image recognition software to be adjusted to 
specifically identify and respond to the SAE J3069 test fixture and 
test track without necessarily ensuring adequate real-world 
performance.
---------------------------------------------------------------------------

    \120\ See Section VIII.O, Regulatory Alternatives.
    \121\ Auto Innovators also suggested using standardized 
headlamps and taillamps in lieu of the proposed broad range of 
actual stimulus vehicles.
---------------------------------------------------------------------------

    We also received comments on the proposed stimulus vehicle lighting 
that are equally relevant to test fixture lighting. Bosch recommended 
that, to ensure system robustness, NHTSA specify stimulus vehicles with 
a wide variety of light source technologies and consider utilizing a 
reference publication such as the Ward's Automotive Yearbook to stay 
current with rapidly evolving headlamp technology. Honda noted that the 
NPRM did not specify which headlamp beams should be activated on the 
stimulus vehicle and suggested that the final rule clarify that this is 
the lower beam. Auto Innovators raised the possibility of a situation 
where the regulation specifies a specific vehicle or vehicle component, 
but the item is later determined to be noncompliant or subject to 
manufacturer in-cycle design changes or modifications. Auto Innovators 
suggested that this potential for non-compliance presents an 
unforeseeable uncertainty to the compliance process, because such 
changes will not always be known at the time a manufacturer of the ADB 
vehicle conducts self-certification testing or to a third-party 
conducting compliance testing for the agency.
Agency Response
    The final rule specifies test fixtures conforming to SAE J3069 with 
respect to the types of fixtures and photometer placement. The final 
rule departs from SAE J3069 by specifying vehicle lamps from high-
selling vehicles instead of lamps intended to simulate vehicle 
lighting.
    The final rule specifies the same four types of fixtures specified 
in SAE J3069: An oncoming car/truck fixture; a preceding car/truck 
fixture; an oncoming motorcycle fixture; and a preceding motorcycle 
fixture. The final rule follows the SAE specifications for the 
locations of the stimulus lighting. SAE based these locations on data 
regarding the typical mounting locations of vehicle lighting. NHTSA 
agrees that these locations are appropriate, and within the FMVSS No. 
108 mounting location requirements.
    The rule also follows SAE J3069 for the locations of the 
illuminance meters. SAE based these locations on data regarding typical 
driver's eye heights and mounting locations for the rearview/side 
mirrors. The illuminance meter locations specified in the final rule 
are the same as in the proposal, with one exception. In its recent 
revisions to SAE J3069, SAE revised the specifications for the 
placement of the illuminance meters (corresponding to two side-view 
mirrors) on the preceding motorcycle fixture. The revision notes that 
the figure depicted in the prior version of the practice showed the 
mirrors to be 0.2 m from the centerline of the rear position lamp, 
which is not consistent with the FMVSS No. 111 required minimum. FMVSS 
No. 111 requires that each motorcycle have a mirror ``mounted so that 
the horizontal center of the reflective surface is at least 279 mm 
outward of the longitudinal centerline of the motorcycle.'' \122\ The 
revised version of SAE J3069 shows the motorcycle mirror separation to 
be 0.4 m, which is consistent with the FMVSS No. 111 required minimum. 
The specification in the final rule adopts this revised specification.
---------------------------------------------------------------------------

    \122\ S10.1.
---------------------------------------------------------------------------

    We did, however, agree with Mobileye that--as we also tentatively 
concluded in the NPRM--the simulated lamps specified in SAE J3069 would 
not be sufficiently realistic. We therefore agreed with Mobileye's and 
Auto Innovators' suggestions to use standardized vehicle lamps on the 
fixtures. The final rule therefore departs

[[Page 9947]]

from SAE J3069 and specifies actual vehicle lamps for the fixtures. The 
reasons for this choice are explained in more detail below. The final 
rule specifies headlamp assemblies from a 2018 Ford F-150 (halogen) and 
a 2018 Toyota Camry (LED). For motorcycles, the final rule specifies a 
5.75 inch headlamp assembly from a 2018 Harley Davidson Sportster using 
an HB2 replaceable light source.\123\ The rule specifies right and left 
taillamp assemblies from a 2018 Ford F-150 incandescent rear 
combination lamp and right and left tail lamp assemblies from a 2018 
Toyota Camry combination lamp. For motorcycles, the final rule 
specifies a layback LED taillamp assembly from a 2018 Harley Davidson 
Roadster.
---------------------------------------------------------------------------

    \123\ This is different than the motorcycle headlamp used in 
NHTSA recent testing. For that testing, NHTSA used a 5.75 inch 
bullet headlamp kit from a 2018 Harley Davidson Roadster using an 
HB2 replaceable light source (part #68593-06). After that testing 
and before the publication of this final rule, that part went out of 
production and has been replaced with part #68297-05B.
---------------------------------------------------------------------------

    There were several reasons for specifying actual vehicle lamps. 
NHTSA agrees with the concerns Mobileye identified regarding the use of 
synthetic fixture lighting and with Intertek that specifying synthetic 
lighting could result in vehicle manufacturers programming systems to 
recognize unrealistic fixtures, thus decoupling compliance test 
performance from actual performance.\124\ The agency's intent was to 
specify a variety of light source technologies that are common in the 
market in order to assess how an ADB system performs with respect to 
light systems it will encounter while in actual use on the roads. This 
will discourage manufacturers from designing specifically to fixture 
lamps lacking characteristics typical of actual automotive lamps (e.g., 
non-uniform illuminance, variations in shape). Using actual vehicle 
lamps also reduces the cost of manufacture of the test fixture (since 
the highly specialized SAE fixture lighting is much more expensive). 
The agency agrees with Bosch that it is important that the lamps on the 
fixtures continue to be representative of vehicle lamps in use. To that 
end, NHTSA envisions future technical rulemakings to amend the lamps 
specified in the regulatory text.
---------------------------------------------------------------------------

    \124\ SAE J3069 MAR2021 added a note requiring that any pulse 
width modulation or similar frequency control be sufficiently above 
the commercial power grid frequency and updated the conical angle 
specification. Even with these changes, NHTSA still believes that 
the finalized vehicle lighting is more appropriate.
---------------------------------------------------------------------------

    The agency also does not believe that the synthetic light sources 
specified in SAE J3069 represent a worst-case scenario. As NHTSA 
explained in the NPRM, the minimum taillamp intensities allowed by 
FMVSS No. 108 (2.0 cd at H-V and as low as 0.3 cd at 20 degrees) are 
considerably lower than the 7.0 cd lamp specified in SAE J3069. NHTSA 
also does not agree with SAE that specifying actual vehicle headlamps 
would result in excessive variability, but continues to believe, as 
stated in the NPRM, that gradients in typical headlamp beam patterns 
would likely 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 (especially 
since the specified headlamps are from high-selling vehicles and 
therefore common on the road), and this should not be considered 
variability attributable to the test, but a failing of the ADB system. 
In any case, NHTSA's testing showed that the tested ADB system was 
generally able to recognize the fixtures fitted with these lamps. 
Comparative test data for the SAE fixtures and the final rule fixtures 
is presented in the discussions for each scenario (see Section 
VIII.C.8).
    The final rule also clarifies various aspects of the test 
procedures related to the fixture lamps. It clarifies that the stimulus 
headlamps will have the lower beam activated and aimed per the SAE 
Recommended Practice J599 Lighting Inspection Code (J599) procedures, 
as applicable. The final rule also specifies how to power the fixture 
lamps. SAE J3069 does not specify how to power the test-fixture 
lighting; this could leave open the possibility of powering the fixture 
in ways that are dissimilar to how actual automotive head and taillamps 
are powered, and potentially lead to ambiguities in how performance is 
measured. Accordingly, the final rule specifies that the lamps will 
have been energized for at least 5 minutes before each test scenario 
trial is performed.
    The agency considered Mobileye's comment that the fixture should 
resemble a ``standard'' vehicle but decided not to adopt this. Using a 
fixture incorporating vehicle elements (e.g., hood, grill) raises 
issues of which elements to specify and how to specify them. NHTSA did 
consider implementing a portion of a vehicle in the fixtures, such as a 
partial front or rear section of a vehicle that would include the 
original equipment lamps as mounted in the production vehicle. 
Including a portion of the actual vehicle body would provide a more 
real-world stimulus with the added detail of some elements of vehicle 
shape and light reflections on the body surfaces. However, while this 
option was not examined in NHTSA's research, our research did not 
demonstrate any significant difference in ADB response between actual 
stimulus vehicles and the test fixtures we are specifying, suggesting 
that adding detail elements to the fixture is not necessary.\125\
---------------------------------------------------------------------------

    \125\ SAE J3069 MAR2021 allows the fixture to be ``constructed 
in a manner that represents the intended vehicle type to avoid false 
readings that the stimulus fixture is not a vehicle'' (sections 
5.5.2.1 and 5.5.3.1). As noted in the text, we considered but did 
not examine this alternative. However, we believe, based on the 
results of our testing (see Section VIII.C.2, Test Fixtures vs. 
Stimulus Vehicles), that specifying actual vehicle lamps makes the 
fixtures sufficiently realistic so that the ADB system will 
recognize the fixture as a vehicle.
---------------------------------------------------------------------------

    With respect to Auto Innovators' comment regarding the possibility 
of a noncompliance of actual vehicle components used as a stimulus in a 
compliance test, NHTSA recognizes this possibility, but anticipates 
that the laboratory test procedures will provide for confirming that 
the vehicle lamps used on the test fixture comply with the applicable 
FMVSS No. 108 photometry requirements.
7. Test Fixture Placement
    The proposal specified stimulus vehicles in the adjacent left lane 
to evaluate oncoming glare. To evaluate preceding glare, it essentially 
specified the stimulus vehicle either in the same lane as the test 
vehicle or in the adjacent left lane.
    The final rule, while specifying test fixtures, generally follows 
the NPRM approach. The test fixture will be placed in the adjacent left 
lane (from the perspective of the test vehicle) to evaluate both 
oncoming glare and preceding glare, essentially the same placement as 
proposed.\126\ See Figure 10 (Figures 27-28 in the regulatory text). 
This corresponds to Fixture Position 2 in SAE J3069. The final rule 
does not specify fixtures situated similarly to SAE Positions 1 and 3. 
In the SAE test method, fixtures placed in those locations are 
primarily intended to simulate curves; the final rule includes curved-
path scenarios, so simulating curves with strategic fixture placement 
is not necessary. The final rule also specifies that the projection of 
the fixture lamp's optical axis onto the road surface should be tangent 
to the road edge at the location of the photometer, and that the 
fixture be centered in the lane.
---------------------------------------------------------------------------

    \126\ The test vehicle will be driven within the right adjacent 
lane and will not change lanes.

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[[Page 9948]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.010

BILLING CODE 4910-59-P
    NHTSA acknowledges that it is common in real-world driving for 
preceding vehicles to be located in the same lane or in the adjacent 
right lane. However, the agency believes that simply testing with the 
preceding fixture in the left adjacent lane will not result in a loss 
of information about ADB system performance. The purpose of the testing 
is to evaluate whether the ADB system is working in an integrated 
fashion; this can be done on either side. While real-world situations 
with a stimulus to the right side are common, it is reasonable to 
expect that if a system functions on the left it will also function on 
the right. Further, the final rule also has tests that include curves 
to the right, where the detection system is exercised (limited to 
oncoming and limited distances) on the right side of the field of view.
8. Test Scenarios \127\
---------------------------------------------------------------------------

    \127\ The test scenario numbering used in the preamble and in 
the final rule regulatory text (at Table XXII) differs somewhat from 
the test scenario number in the ADB test report and repeatability 
assessment docketed with this final rule.
---------------------------------------------------------------------------

a. Scenario 1: Oncoming Straight
    The NPRM proposed testing for oncoming glare in a straight-path 
test scenario at speeds from 60 mph to 70 mph at measurement distances 
of 15 m to 220 m.
Comments
    ALNA, Toyota, SAE, and the Alliance commented that the proposed 
glare limits are at or well below those regularly occurring today from 
lower beams, including, the commenters appeared to suggest, in a 
straight-path scenario. SAE and the Alliance stated that the glare 
limits are not reasonable if lower beams, including IIHS ``Good''-rated 
lower beams, would fail to comply. SAE provided a graphical analysis 
(based on IIHS data) of lower beam illuminance on a straight road (from 
0 m to 125 m) for nine MY 2017 IIHS Top Safety Picks, all with FMVSS 
108-compliant IIHS-rated ``Good'' headlamps. The graph shows that 
almost all those headlamps complied with the proposed glare limits at 
all proposed measurement distances.
Agency Response
    NHTSA is finalizing the proposed specifications for this scenario, 
including the proposal to evaluate illuminance from 15 m to 220 m. The 
rule thus evaluates glare across a broader range of distances than SAE 
J3069, which evaluates glare at 30 m, 60 m, 120 m, and 155 m, 
respectively. The reasons for choosing this range are discussed in the 
NPRM (83 FR at 51778-51781) and elsewhere in this preamble.
    The available data indicate that current lower beams can comply 
with the glare limits in this scenario. The IIHS data submitted by SAE 
show that the lower beams for the 9 vehicles for which data was 
provided were generally within the glare limits on a straight road for 
all the distances for which the final rule regulates glare. NHTSA's 
testing also shows that current lower beams would pass this scenario. 
NHTSA tested the lower beams of a MY 2019 Ford Fusion and MY 2016 Volvo 
XC90 in this scenario. The measured illuminance of the lower beams was 
found to be within the glare limits by a considerable margin at all 
distances. See Figure 11 and Figure 12.\128\
---------------------------------------------------------------------------

    \128\ The illuminance measured from the higher-mounted 
photometer representing the truck driver eye point, is, as expected, 
lower than that measured from the lower-mounted photometer intended 
to represent a passenger car driver's eye point. For that reason, 
some of the test data included in this preamble may not report the 
illuminance values measured from the higher-mounted illuminance 
meter.

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

[[Page 9949]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.011

    NHTSA's analysis and testing also indicate that current ADB systems 
can reasonably be expected to comply with this scenario. As Figure 7 
makes clear, the fixture is within the ADB camera's field of view at 
the beginning of the measurement range, at less than 5 degrees left of 
the center of the field of view. (As noted earlier, the field of view 
of current ADB systems extends to about 25 degrees left and right.) 
Accordingly, the ADB system should have sufficient time to detect and 
react to the fixture stimulus lamps and adjust the beam. The agency's 
ADB test data confirms this. For example, the ADB system we tested was 
within the glare limits at all distances when tested with the oncoming 
car/truck fixture. See Figure 13. Additionally, NHTSA's 2015 testing 
showed that an older ADB system was able to pass this scenario even 
when tested with stimulus vehicles, both moving and stationary.\129\
---------------------------------------------------------------------------

    \129\ 2015 ADB Test Report at p. 103 (Table 23) (results for 
Audi show adaptive beam within the glare limits at all distances on 
the straight scenario, with both a static and dynamic stimulus 
vehicle). Audi indicated that the shaded area of the adaptive beam 
complied with the FMVSS No. 108 lower beam requirements.
---------------------------------------------------------------------------

    The ADB system also passed the SAE scenario that is the closest 
analog to this scenario (with the car/truck test fixture in Position 
2), and NHTSA did not see a significant difference between performance 
on the NHTSA and SAE test protocols here.\130\ See Figure 13.
---------------------------------------------------------------------------

    \130\ Agency testing showed some anomalies when testing with the 
motorcycle fixtures (both the final rule fixture and the SAE 
fixture). For that reason, the results of that testing are discussed 
separately. See Appendix C.

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[[Page 9950]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.012

b. Scenario 2: Oncoming Small Left Curve
    The NPRM provided for testing oncoming glare on left curves with 
radii of 98 m to 116 m, at speeds from 20 mph to 30 mph, for the full 
range of 15 m to 220 m.
Comments
    In addition to general comments from several manufacturers that the 
proposal would require ADB systems to produce less glare than current 
FMVSS No. 108-compliant lower beams, particularly on curves, SAE 
provided a graphical analysis of IIHS data of illuminance from nine 
``Good''-rated lower beams from 0 m to 125 m on a 150 m left curve. The 
data show that almost all the lower beams were within the glare limits 
in this entire range, except that one vehicle occasionally exceeded the 
glare limits between 15 m and 60 m, one vehicle exceeded the glare 
limits at 15 m, and a couple of vehicles exceeded the glare limits 
between about 60 m and 90 m.
    The Alliance, SAE, OICA, and SMMT commented that current ADB 
systems would not comply with this scenario because it would 
necessitate a camera field of view wider than provided on current ADB 
systems. The Alliance stated that the camera visibility needed to 
detect a stimulus vehicle on this curve is almost 45 degrees (with a 
median) and 40 degrees (without a median). Both the Alliance and SAE 
contended that, should this scenario be retained, camera visibility 
would have to be extended, which would increase costs, potentially 
diminish performance in the more critical central portion of the 
visibility zone, and create dis-harmonization, limiting the 
availability of ADB systems in the United States. SAE also stated that 
upper beams at greater than 15 degrees left or right are not as bright 
as lower beams straight ahead, and at an angle of 40 degrees the light 
toward a stimulus vehicle driver is low. SAE stated that this is 
supported by the fact that millions of semiautomatic beam systems on 
the roads today are equipped with the same or similar forward vision 
cameras and detection algorithms as ADB systems and have not resulted 
in glare complaints. This suggests, SAE asserted, that wide angle 
visibility (i.e., beyond 25 degrees) is unnecessary and precludes any 
need to test on curves of these radii.
    Honda commented that the proposed 0.1 s or 1 m allowance for 
momentary spikes does not allow enough time for an ADB system to 
respond to sudden changes in stimulus lighting, and that this 
especially might be an issue on curves with a radius of 98 m-116 m, on 
which an opposing vehicle will enter the ADB system's field of view 
suddenly at a close distance.
Agency Response
    The final rule retains this scenario but modifies the distances at 
which illuminance from the ADB system is evaluated: The measurement 
range now begins at 59.9 m \131\ instead of the proposed 220 m. The 
reasons for this are explained below.
---------------------------------------------------------------------------

    \131\ In the regulatory text this is specified as ``less than 60 
m.'' Other distance specifications are stated similarly. The 
preamble discussion simplifies this for ease of exposition.
---------------------------------------------------------------------------

    First, the available data indicate that current, FMVSS 108-
compliant lower beams might not comply with the glare limits at 
distances greater than 60 m but would generally comply at closer 
distances. The IIHS data submitted by SAE show that almost all the 
tested lower beams were almost fully within the glare limits in the 
modified distance range (15 m-59.9 m), while some of the lower beams 
exceeded the glare limits for distances greater than 60 m. NHTSA's 
testing also shows that current lower beams would pass this modified 
scenario. NHTSA tested two vehicles with lower beams activated on an 85 
m left curve, and both vehicles performed well with considerable 
margins. See Figure 14.

[[Page 9951]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.013

    Next, NHTSA believes that this modified specification is within the 
capabilities of most current ADB systems. On a curve with a 100 m 
radius, at the highest vehicle speed specified for this scenario (30 
mph), the fixture will enter the camera's field of view (25 degrees) at 
77 m (see Figure 7). At the distance at which the final rule begins 
evaluating the system's illuminance (59.9 m), the fixture is therefore 
well within the camera's field of view (at about 21 degrees). The 
fixture is not only within the camera's FOV, but has been within the 
FOV for 1.24 s, which is a sufficient time for an ADB system to react. 
NHTSA acknowledges that for shorter radii in the specified range, the 
time elapsed between the fixture entering the system's field of view 
and the test vehicle reaching the beginning of the evaluation range 
(59.9 m), may not provide sufficient time for an ADB system to react 
and switch from an area of unreduced intensity (i.e., upper beam) to an 
area of reduced intensity. For example, on a curve with an 85 m radius 
at 30 mph, the fixture will enter the camera's field of view at 63 m. 
At 59.9 m, the fixture will have been within the system's FOV for 0.13 
s. The agency does not, however, expect this to result in a 
noncompliance because at that distance the headlamps are at a large 
enough angle to the photometer that the upper beam should be within the 
glare limits. (Agency testing generally showed that the upper beam was 
within the glare limits at angles greater than 20 degrees. There are no 
upper beam photometry requirements at angles wider than 12 degrees. At 
12 degrees, Table XVIII specifies (depending on the type of upper beam) 
a minimum of, at most, 1,500 cd (at horizontal) and 1,000 cd (at 2.5D).
    NHTSA's ADB test data bear this out. When NHTSA tested an ADB 
system at 29 mph on a curve at the upper bound of the range (115 m), 
the ADB system detected and reacted to the fixture prior to the 
measurement range. See Figure 15. On the other hand, when testing the 
ADB system on a curve at the lower bound of the radius range (85 m), 
the system did not react to the fixture and dim the beam until 41 m--
which is after the specified beginning of the measurement range (59.9 
m). See Figure 16. However, the illuminance (the upper beam) at these 
large angles was below the applicable glare limit, and the system was 
able to react and adapt the beam before the geometry was such that the 
narrower angle of the upper beam would exceed the glare limit.

[[Page 9952]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.014

    NHTSA also tested the SAE scenario that is the closest analog to 
this scenario (with the oncoming fixtures in Position 1) and observed 
no glare limit exceedances. See Figure 17. However, the illuminance 
was, for closer distances, significantly lower than the illuminance 
measured during the corresponding final rule scenario. This is because, 
as the test vehicle approaches the SAE fixture, the fixture moves more 
and more off-angle from the test vehicle as the distance closes, 
resulting in lower-than-expected illuminance.

[[Page 9953]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.015

    NHTSA notes that this scenario, as modified, does not evaluate 
illuminance from 60 m to 220 m, so it would not test whether the ADB 
system switched from an upper beam to an adaptive beam in this range. 
In the NPRM the agency tentatively concluded that it was important to 
regulate illuminance in the full range of 15 m-220 m. However, as 
explained above, NHTSA decided the full range is unnecessary because an 
upper beam projected at angles larger than 20 degrees is not glaring at 
distances beyond those at which we are evaluating illuminance in this 
scenario.
c. Scenario 3: Oncoming Medium Left Curve
    NHTSA proposed testing for oncoming glare on left curves with radii 
of 223 m to 241 m, at speeds of 40-45 mph, for the full range of 15-220 
m.
Comments
    NHTSA received one comment specifically related to this scenario. 
SAE provided a graphical analysis of IIHS illuminance data (out to 125 
m) for nine lower beams on a 250 m left curve showing that all the 
lower beams were within the glare limits, except for two headlamps that 
had some exceedances between 60 m and 110 m. As noted earlier, some 
commenters argued more generally that the proposed glare limits were so 
stringent that even currently-compliant lower beams would exceed them.
Agency Response
    The final rule modifies the measurement range, which now begins at 
150 m instead of the proposed 220 m. The rationale for this is 
analogous to the rationale for limiting the measurement distances for 
the small left curve.
    First, the available data indicate that compliant lower beams would 
generally comply with these requirements. As explained earlier, this 
(in conjunction with the requirement that areas of reduced intensity 
meet the corresponding lower beam laboratory photometric requirements) 
means that an area of reduced intensity, up to and including a full 
lower beam, will meet the same level of safety (with respect to both 
visibility and glare prevention) as current lower beams certified to 
FMVSS No. 108. The IIHS data submitted by SAE shows that almost all the 
tested lower beams complied with the glare limits for the distances for 
which data was reported. NHTSA's testing also shows that current lower 
beams would pass this modified scenario; both lower beams NHTSA tested 
had illuminance values within the glare limits by a considerable 
margin. See Figure 18.

[[Page 9954]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.016

    Next, NHTSA's analysis also indicates that the modified 
specifications are within the field-of-view and adaptation time 
capabilities of most current ADB systems. For example, on a 230 m curve 
at 45 mph, over two seconds elapse between the fixture entering the 
field-of-view and the vehicle reaching the measurement range (150 m), 
providing the ADB system sufficient time to react and adapt the beams. 
As with the small left curve, however, for shorter radii in the 
specified range, the time elapsed between the fixture entering the ADB 
system's field of view and the vehicle reaching the beginning of the 
measurement range may not provide sufficient time for the ADB system to 
adapt and switch from an area of unreduced intensity to an area of 
reduced intensity. For example, on a 210 m curve, only .57 seconds 
elapse. However, as with the small left curve, at those distances the 
headlamps are at a large enough angle to the photometers that the upper 
beam should be within the applicable glare limit.
    Again, NHTSA's ADB test data bears this out. NHTSA tested an ADB 
system on a 210 m left curve at 44 mph. See Figure 19. The measured 
illuminance values were within the glare limits except for two 
exceedances lasting less than 0.1 s (which would not be considered a 
noncompliance because they are within the allowance for momentary glare 
exceedances). The ADB system reacted to the fixture at 120 m. Prior to 
that (i.e., from 150 m to 121.9 m), the ADB system was projecting an 
upper beam, but the upper beam was within the glare limits.
    In comparison, when testing the most analogous SAE test scenario 
(with the fixture in Position 1) there were no glare limit exceedances, 
and, at closer distances, the SAE test scenario resulted in lower 
illuminance values than were measured on the actual left curve.
[GRAPHIC] [TIFF OMITTED] TR22FE22.017

[[Page 9955]]

    In addition, as noted earlier for the small left curve scenario, 
although the final rule reduces the start of the measurement distance 
in this scenario from 220 m to 150 m, this should not present a risk 
that oncoming vehicles will experience glare outside of 150 m for the 
reasons discussed earlier.
d. Scenario 4: Oncoming Large Left Curve
    The NPRM specified testing for oncoming glare on left curves with 
radii of 335-396 m, at speeds of 50-55 mph, from 15 m to 220 m.
Comments
    NHTSA did not receive any comments that related specifically to 
this curve. Commenters argued more generally that currently-compliant 
lower beams would not always comply with the glare limits, especially 
on curves, and that there might not be sufficient time for the ADB 
system to react to the stimulus lighting.
Agency Response
    The final rule adopts this scenario essentially as proposed (the 
largest-specified radius of curvature has been rounded up). Both a 
lower beam and an ADB system can reasonably be expected to comply with 
the glare limits throughout this range.
    The available data indicate that current FMVSS No. 108-compliant 
lower beams can comply with the glare limits in the full measurement 
range. The IIHS data submitted by SAE did not include a left curve with 
a radius this large. However, the IIHS data did include lower beam 
performance on a 250 m radius left curve and a straight road. As 
explained in the preceding section for the medium left curve scenario, 
all the IIHS-tested headlamps were essentially within the glare limits 
at all distances for which data was reported (out to about 125 m) on 
both the 250 m left curve and the straight road. Because the curve in 
this scenario is essentially between a 250 m left curve and a straight 
road, it is reasonable to extrapolate that the lower beams tested by 
IIHS would also have complied on left curves with radii greater than 
250 m. NHTSA's test data confirms this. Both the Fusion and the Volvo 
lower beams were within the glare limits on this curve. See Figure 20.
[GRAPHIC] [TIFF OMITTED] TR22FE22.018

[[Page 9956]]

    These specifications are also within the capabilities of current 
ADB systems. On a curve with a 335 m radius at the highest speed 
specified for this scenario (55 mph), the fixture will enter the 
camera's field of view (25 degrees) at 283 m (see Figure 7). At the 
distance at which we will begin evaluating the system's illuminance 
(220 m), the fixture is therefore well within the camera's field of 
view (at about 20 degrees), and has been within the FOV for 1.27 s, 
which is sufficient time for an ADB system to react.
    NHTSA's testing confirmed this. The ADB system tested was generally 
able to respond and shade the fixture in this scenario. See Figure 21. 
The system reacted at 185 m and performed well from a recognition 
standpoint. The area of reduced intensity exceeded the limits in the 
60-120 m range as well as the 30-60 m range. Because these exceedances 
last longer than 0.1 s. and occur while the vehicle pitch is less than 
0.3 degrees from the average pitch throughout the run, these 
exceedances would be considered possible noncompliances. However, these 
failures are relatively marginal, and the beam pattern could be 
modified to fully comply with this scenario.
[GRAPHIC] [TIFF OMITTED] TR22FE22.019

    As with the other oncoming left curve scenarios, the closest SAE 
test analogue is with an oncoming fixture in Position 1. Again, NHTSA's 
testing showed that, compared to NHTSA's test, the SAE test resulted in 
much lower illuminance at close distances than on an actual curve. See 
Figure 22. Thus, data indicate again that the two test methods can 
yield different results, and that the actual curve test is preferable 
because it would be more evaluative of real-world performance.
[GRAPHIC] [TIFF OMITTED] TR22FE22.020

BILLING CODE 4910-59-P
e. Scenario 5: Oncoming Medium Right Curve
    The NPRM proposed regulating glare on right curves with a radius of 
223 m to 241 m, at speeds of 40-45 mph, from 15 m to 220 m.
Comments
    SAE provided a graphical analysis of illuminance data for nine IIHS 
``Good''-rated lower beams on a 250 m radius right curve from 0 m to 
125 m and

[[Page 9957]]

stated that it demonstrated none of those lower beams would meet the 
proposed glare limits. Other commenters argued more generally that 
current lower beams would exceed the proposed glare limits, especially 
on curves. Intertek commented that NHTSA should limit the range for 
right-hand curves to account for lower beam patterns at 3 degrees 
right. Stanley ran simulations for a 232 m radius right curve and 
commented that the proposed glare limits appeared to be inconsistent 
with the current photometric requirement for lower beams at several 
points (especially from 1R to 3R). It asked that the agency reconsider 
the proposed glare limits and make them consistent with the current 
regulatory requirements for lower beams.
Agency Response
    The final rule retains this scenario but revises the measurement 
range to begin at 50 m instead of the proposed 220 m.
    NHTSA agrees with the commenters that current compliant lower 
beams--especially ones that perform well on the IIHS test--would likely 
not comply with the glare limits from 51 m-220 m. The IIHS data 
submitted by SAE show that almost all the lower beams tested by IIHS 
exceeded the glare limits at distances of 60 meters and greater on a 
250 m right curve. NHTSA also examined IIHS lower beam data for a 2020 
Toyota Camry with ``Good''-rated LED lower beams.\132\ IIHS measured 
that vehicle on a 250-m radius curve to have a 5-lux line at 79.5 m 
\133\ (70 m is the minimum without receiving demerits), which would 
exceed the applicable glare limit at that distance (0.6 lux).
---------------------------------------------------------------------------

    \132\ See www.iihs.org/ratings/vehicle/toyota/camry-4-door-sedan/2020#headlights (last accessed Dec. 18, 2020).
    \133\ Corresponding to approximately 0.3D, 7R.
---------------------------------------------------------------------------

    After considering the comments, NHTSA has determined that these 
results should have been generally expected based on a comparison of 
the oncoming glare limits and the longstanding Table XIX lower beam 
photometry requirements that regulate lower beam design. The oncoming 
glare limits were derived from the Table XIX left-side maxima (700 cd 
at 1U, 1.5 L to L and 1,000 cd at 0.5 U, 1.5L to L).\134\ On a right 
curve, however, the fixture enters the lower beam pattern from the 
right side and traces a trajectory across the beam pattern from right 
to left (See Figure 7). The Table XIX right-side maxima (1,400 cd at 
1.5U, 1R to R and 2,700 cd at 0.5U, 1R to 3R) are higher than the left-
side maxima. In addition, unlike on the left side, the right-side 
photometry is not limited at 0.5U extending indefinitely horizontally. 
The left-side photometry is limited by the line 0.5U, 1.5L-L. The 
right-side photometry is limited by 0.5U, 1R-3R. While right-side 
photometry is ultimately limited at 1.5U, 1R-R, this line provides 
considerably more flexibility to provide light down the right side. 
Consequently, the Table XIX right-side maxima, on which current lower 
beams are based, permit intensities that exceed the oncoming glare 
limits, which were derived from the left-side maxima. Indeed, data show 
that current compliant lower beams exceed the derived glare limits on 
the right side at distances greater than 50 m. More specifically, based 
on the IIHS data presented by SAE, exceedances at about 3R and greater 
(corresponding to measurement distances of greater than about 50 m) are 
found, and many fewer glare limits exceedances to the left of 3 degrees 
right. Accordingly, the final rule revises this scenario so that the 
measurement range does not start until 50 m.
---------------------------------------------------------------------------

    \134\ Feasibility Study, p. 23.
---------------------------------------------------------------------------

    The agency notes that even with this modification, the glare limits 
in this final rule are still (as Stanley suggested) more stringent than 
currently allowed by the Table XIX right-side maxima from 1R to 
3R.\135\ However, this level of stringency is reasonable and provides a 
manageable design range. The lower beam photometry was designed to 
provide a generic beam to prevent glare regardless of the actual road 
and traffic conditions; it was not customized to provide glare 
protection to oncoming vehicles on a right curve. Because most 
situations in which an oncoming vehicle can be glared will occur with 
the oncoming vehicle to the left, the existing Table XIX lower beam 
photometry requirements require shading the left side and permit more 
light on the right side. However, the adaptive driving beam is not, and 
need not be, an all-purpose beam like a conventional lower beam. It is 
clear in the photometry tables that the appropriate glare limits for 
oncoming situations are the left-side maxima in Table XIX, on which the 
oncoming glare limits are based. These limits should, to the extent 
possible, apply to oncoming glare, including from the right-side. In 
any case, the agency believes that current lower beams would generally 
comply with the glare limits as applied in this scenario with the 
revised measurement distance range.
---------------------------------------------------------------------------

    \135\ In Appendix A, we provide additional data and discussion 
on this.
---------------------------------------------------------------------------

    Indeed, both IIHS and NHTSA lower beam test data demonstrate that 
compliant lower beams, including high-rated IIHS beams, would generally 
be within the glare limits in this revised scenario. The IIHS data 
submitted by SAE shows that for distances between 15 m and 60 m, most 
of the lower beams were within the glare limits. Vehicles 1 and 7 seem 
to take the most advantage of the flexibilities provided toward the 
right side beyond 3 degrees in performing well in the IIHS right-curve 
test, and the lower beams on both vehicles were below the glare limits 
within 50 m. This demonstrates that a vehicle can both perform well on 
the IIHS right-curve distance rating and stay within the glare limits 
in this final rule's revised scenario.
    NHTSA's testing also showed that current lower beams can pass this 
revised scenario. NHTSA tested two lower beams on a 210 m right curve, 
and both were within the glare limits at all distances within the 
specified measurement range. See Figure 23. The agency also saw similar 
results in our 2015 testing, which (among other things) evaluated lower 
beam illuminance on a 231 m right curve, and found that the lower beams 
exceeded the glare limits at 60 meters and greater, and was within the 
glare limits from 15 m to 60 m.\136\
---------------------------------------------------------------------------

    \136\ 2015 ADB Test Report, p. 193 (Fig. 85, Mercedes Trial 82 
[lower beam]); p. 63 (Mercedes test vehicle modified by manufacturer 
to produce a FMVSS No. 108 compliant beam pattern).

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[[Page 9958]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.021

    NHTSA notes that these data from contemporary lower beams differ 
somewhat from data on 1990s-era lower beams presented in the 
Feasibility Study. Specifically, Figure 9 in the Feasibility Study, 
which displayed a lower beam pattern typical of MY 1997 vehicles, seems 
to indicate that lower beams would likely be within the oncoming glare 
limits on the right side of the beam pattern illustrated in Figure 9. 
However, as Auto Innovators pointed out in its comment, lower beam 
design has changed since 1997. NHTSA believes it is reasonable to 
assume that at least some manufacturers are supplying more light at or 
just above the horizon for horizontal angles greater than 3 degrees 
right (without violating the 1,400 cd maximum) than in the past in 
order to perform well on the IIHS tests.\137\ Lower beams that are 
designed to perform well on the IIHS test may thus be more likely to 
fail the glare limits in the ADB track test, even if the system is 
projecting an area of reduced intensity onto the fixture. This is 
compounded by the effect of vehicle pitch: With higher intensity light 
at larger vertical angles of the beam pattern, slight changes in pitch 
can push the higher intensity portion of the lower beam upwards and 
cause the oncoming glare limit to be exceeded. Further, at angles 
beyond 3 degrees right, the glare limits begin to veer dramatically 
from the flexibilities provided in the current Table XIX requirements 
(specifically, the right-side maxima). Accordingly, the oncoming glare 
limits, in conjunction with the revised measurement distances, are 
consistent with the angular limits of the current lower beam 
photometry. The track test continues the longstanding flexibilities for 
lower beam design on the right side beyond 3 degrees.
---------------------------------------------------------------------------

    \137\ Comment from Alliance for Automotive Innovation (July 31, 
2020) (NHTSA-2018-0090-0219), p. 11 (Fig. 5, Low-Beam Headlight 
Intensity Pattern from IIHS Headlight Rating.
---------------------------------------------------------------------------

    The modified specifications for this scenario are also within the 
capabilities of typical ADB systems. Because illuminance is evaluated 
starting at 50 m from the fixture, there is more than enough time for 
an ADB system to detect and react to the fixture (more than 7 seconds 
on a 230 m radius curve).
    The agency's ADB test data bear this out. When testing an ADB 
system on a 210-meter radius right curve, the illuminance was within 
the glare limits except for some limited exceedances, which can readily 
be addressed by minor changes in the design of the area of reduced 
intensity. See Figure 24. Similarly, the 2015 testing with actual 
stimulus vehicles showed that even an older ADB system was able to pass 
a right curve (231 m) oncoming scenario at 15 m to 50 m.\138\
---------------------------------------------------------------------------

    \138\ 2015 ADB Test Report, p. 193 (Fig. 85, Mercedes Trial 83 
[ADB]); p. 63 (Mercedes test vehicle modified by manufacturer to 
produce a FMVSS No. 108 compliant beam pattern).

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[[Page 9959]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.022

    The ADB system NHTSA tested had more exceedances when tested to the 
most closely analogous SAE J3069 scenario (with the test fixture in 
Position 3) compared to NHTSA's test. See Figure 25. This is because at 
the measurement distances in this scenario, Fixture Position 3 is in 
the bright (right-side) portion of the beam pattern, while the fixture 
in NHTSA's test scenario is in the less-bright portion of the beam 
pattern (center-right to center-left).
[GRAPHIC] [TIFF OMITTED] TR22FE22.023

    NHTSA notes that this scenario does not evaluate the illuminance 
from the ADB system from 50 m-220 m, so it would not test whether the 
ADB system switched from an upper beam to an adaptive beam in this 
range. NHTSA believes this is acceptable because the left curve 
scenarios generally test the ability of the ADB system to react and it 
is reasonable to expect similar reactions on the left and right side. 
The right curve test simply confirms the right side is performing 
similarly by applying the oncoming glare limits to narrow angles on the 
right side and providing greater flexibility at broader angles on the 
right side of the vehicle.
f. Scenario 6: Oncoming Large Right Curve
    The NPRM proposed regulating glare on right curves with a radius of 
335 m to 396 m at 50-55 mph from distances of 15 m to 220 m.

[[Page 9960]]

Comments
    As explained above regarding the medium right curve scenario, 
Stanley ran simulations for right curves with a radius of 366 m and 
commented that the oncoming glare limits were effectively more 
stringent than the current Table XIX photometry on the right side of 
the beam pattern. In addition, as noted earlier, commenters argued more 
generally that the proposed glare limits were so stringent that 
compliant lower beams would exceed them, and that there might not be 
sufficient time for the ADB system to react to the stimulus lighting.
Agency Response
    This final rule modifies the proposal, similar to the modifications 
for the medium right curve, in response to comments that current 
compliant lower beams might not comply with the NPRM's glare limits at 
all the proposed measurement distances. As explained earlier, this (in 
conjunction with the requirement that areas of reduced intensity meet 
the corresponding lower beam laboratory photometric requirements) means 
that an area of reduced intensity, up to and including a full lower 
beam, will meet the same level of safety (with respect to both 
visibility and glare prevention) as current lower beams certified to 
FMVSS No. 108. As NHTSA agrees with Stanley and other commenters that 
the proposed scenario permitted less glare than presently required of a 
lower beam on the right side of the beam pattern, NHTSA has narrowed 
this angle not to go beyond 3 degrees right, to provide flexibility at 
larger angles. The final rule therefore specifies testing on a right 
curve with a radius of 335--400 m at distances of 15 m to 70 m, at the 
proposed speeds of 50-55 mph.
    NHTSA believes that a lower beam that is FMVSS No. 108-compliant 
and performs well on the IIHS test would generally be able to comply 
with the glare limits in this scenario. The reasons for this are 
analogous to the reasons given earlier for revising the measurement 
distance in the medium right curve scenario. None of the IIHS data 
submitted by SAE was for a right curve of this diameter. NHTSA tested 
two lower beams on this scenario. See Figure 26. The Fusion lower beam 
was within the glare limits at all specified distances, while the Volvo 
lower beam exceeded the glare limits at distances from 60 m--70 m. This 
is likely because, as explained earlier, the Table XIX photometry 
requirements and the IIHS test have prompted some manufacturers to 
provide greater light on the right side. NHTSA believes such systems 
can comply with the requirements with minor modifications. This is also 
consistent with what Stanley points out in its comment.

[[Page 9961]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.024

    The agency also believes that the finalized requirements are within 
the capabilities of existing ADB systems, for reasons analogous to 
those provided for the medium right curve scenario above. The ADB NHTSA 
system tested was within the glare limits in this scenario except at 
distances greater than 60 m. See Figure 27. This is similar to the 
results for the Volvo lower beam and, we believe, can be addressed with 
minor system modifications. Agency test data also confirm that the most 
closely analogous SAE test scenario (Fixture Position 3) does not 
accurately replicate an actual right curve; the measured illuminance on 
this scenario was significantly higher than in the analogous SAE 
scenario. Thus, the data indicate again that the two test methods can 
yield different results, and that the actual curve test is preferable 
because it would be more evaluative of real-world performance.

[[Page 9962]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.025

g. Scenario 7: Preceding Straight
    The NPRM proposed testing for preceding glare in a variety of 
vehicle maneuvers, on both straight and curved roadway. It proposed 
scenarios in which a stimulus vehicle preceded the test vehicle in the 
same lane and in which the test vehicle overtakes the stimulus vehicle, 
and vice versa. We proposed evaluating glare out to 119.9 m.
Comments
    SAE commented, with respect to NHTSA's statement in the NPRM that 
the ECE ADB regulations require ADB cameras to be capable of sensing 
vehicles out to 400 m, that this only applies to opposing vehicles 
(headlamps), not preceding vehicles (rear lamps). For preceding 
vehicles (i.e., tail/rear position lamps), the ECE requirement is 
greater than 100 m. SAE also noted that ECE minimum photometric 
requirements for a rear position lamp is 4 cd versus the 2 cd minimum 
under FMVSS No. 108 for a taillamp. Thus, SAE stated, the ECE requires 
a shorter detection distance (100 m in the ECE versus 120 m in the 
NPRM) for a lamp whose absolute minimum intensity is two times that 
required by FMVSS No. 108.
    Auto Innovators found that there were very few test failures in 
this scenario (5 failures out of 109 valid test runs in its testing) 
and therefore suggested eliminating it because it would provide no 
additional benefit.
Agency Response
    The final rule scales back the proposal with respect to evaluating 
preceding glare. The final rule does not include any passing or same-
lane scenarios because it utilizes stationary fixtures. The final rule 
provides only for testing preceding glare with the fixture in the left 
adjacent lane, on both a straight path (this ``preceding straight'' 
test scenario) and on a left curve path (Scenario 8).
    The final rule also shortens the measurement distance to 100 m. As 
SAE suggested in its comment, the detection distance for ADB systems 
differs for oncoming versus preceding traffic. It is much more 
difficult for an ADB system to detect taillamps than headlamps, and the 
difficulty increases with greater forward distances. This is mainly 
due, as SAE notes, to the fact that headlamps are much brighter than 
taillamps. The NPRM stated that it is reasonable to expect ADB systems 
to detect oncoming vehicles at 220 m but did not mean to imply that 
this also applies to preceding vehicles. The final rule harmonizes with 
the ECE requirements in this respect.
    Agency test data indicate that current lower beams can comply with 
this revised scenario. NHTSA tested two vehicle lower beams, both of 
which performed well, with considerable margin. See Figures 28 and 29 
below.

[[Page 9963]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.026

    NHTSA's analysis also indicates that ADB systems can reasonably be 
expected to comply with this scenario. As explained earlier for the 
oncoming straight scenario, the preceding vehicle fixture--which is in 
the same location as it is for the oncoming straight scenario--is 
always within the ADB system's field of view, so that an ADB system 
will have more than sufficient time to react to and shade the fixture. 
NHTSA's test data bear this out. The Lexus ADB system performed well 
with considerable margins in this scenario with all fixtures (passenger 
car, truck, motorcycle). See Figure 30. On the SAE test run with the 
preceding fixtures in Position 2 (the closest analog to this final rule 
scenario), the ADB system passed with the car/truck fixtures, although 
the margins were lower. See Figure 31.
[GRAPHIC] [TIFF OMITTED] TR22FE22.027

[[Page 9964]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.028

h. Scenario 8: Preceding Medium Left Curve
    The NPRM included scenarios for testing preceding glare on short, 
medium, and large right and left curves, in same-lane and passing 
scenarios. It proposed evaluating glare from 15 m or 30 m (depending on 
the scenario) out to 119.9 m. The agency did not receive any comments 
specifically on the preceding curve scenarios.
    The final rule retains only one preceding curve scenario of those 
proposed. This scenario evaluates preceding glare on a medium left 
curve (with a radius from 210 m to 250 m) from 15 m to 100 m with the 
fixture in the left adjacent lane.
    After considering the comments questioning the number and 
complexity of the proposed test scenarios, NHTSA considered including 
only a preceding vehicle straight path scenario, hypothesizing that it, 
in addition to the full set of oncoming scenarios, would adequately 
probe ADB system performance. NHTSA's testing, however, showed that ADB 
systems encountered some difficulties preventing glare to preceding 
vehicles on curves. The 2015 ADB Test Report concluded that left curve 
same-direction maneuver scenarios in which the stimulus vehicle was 
stationary were associated with high measured illuminance values.\139\ 
NHTSA's recent testing showed that the ADB system, while performing 
adequately on oncoming left curve and preceding straight scenarios, had 
trouble with a preceding left curve scenario for short and medium 
curves, but handled the large curve well. See Figure 32.
---------------------------------------------------------------------------

    \139\ 2015 ADB Test Report, p. 173. See also pp. 114-123.

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

[[Page 9965]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.029

[[Page 9966]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.030

BILLING CODE 4910-59-C
    Accordingly, the final rule retains a preceding left curve scenario 
to help ensure that ADB systems respond appropriately when encountering 
preceding vehicles on curved roadways. NHTSA decided that one curve 
test would suffice and has opted for the medium curve. The ADB system 
we tested performed well on the large curve, and the short curvature 
would be a difficult test for the manufacturers to meet. The final rule 
does not add a right curve scenario for preceding vehicles because the 
2015 study showed that ADB systems generally performed well on same-
direction right curve maneuvers.\140\ Further, because the final rule 
truncates the measurement distances on right curves, preceding tests 
for right curves would not test the system in any significant ways that 
are not already covered by the other scenarios.\141\
---------------------------------------------------------------------------

    \140\ 2015 ADB Test Report, p. 173.
    \141\ For example, the Lexus has a late reaction (at 70 m) on 
the preceding medium left curve. If the recognition system is 
essentially symmetrical (i.e., the same for a right curve), the same 
late recognition (70 m) on a preceding right curve would not result 
in a failure, because the measurement distance for a right curve is 
truncated to 50 m (Scenario 5). As is the case for the left curve, 
the Lexus was under the right curve limits at distances less than 50 
m.
---------------------------------------------------------------------------

    The results from the SAE test fixture position most analogous to 
this final rule scenario (with the SAE fixture in Position 1) show that 
the ADB system passed the test with the car/truck fixture with wide 
margins. See Figure 33. Again, this contrasts with the results from the 
final rule test scenario and suggests that the SAE test does not 
sufficiently replicate a preceding situation on an actual curve.
i. Decision Not To Include Oncoming Short Right Curve Scenario
    The NPRM proposed evaluating illuminance on right curves with a 
radius of 98 m to 116 m at distances of 15 m to 220 m.
Comments
    SAE and Stanley commented--parallel to their arguments for the 
medium right curve--that contemporary lower beams would likely not 
comply with this scenario. SAE provided a graph of illuminance data for 
IIHS ``Good''-rated lower beams from about 0 m to 125 m on a 150 m 
radius right curve. SAE stated that these data show that many of those 
lower beams would not comply with the proposed glare limits at 
distances greater than 30 m. Other commenters stated more generally 
that the proposed glare limits were so stringent that even currently-
compliant lower beams would exceed them. Similarly, Stanley ran 
simulations for a right curve with a radius of 107 m and asserted that 
the glare limits were more stringent than the right-side intensities 
currently permitted by the standard.
    As noted above under the small left curve scenario, several 
commenters stated that curves of this size would require a camera field 
of view beyond the capabilities of existing systems, and/or would not 
allow a sufficient time for an ADB system to detect and react to the 
stimulus.
    SAE also commented that upper beams at greater than 15 degrees left 
or right are not as bright as lower beams straight ahead, and at an 
angle of 40 degrees the light toward a stimulus vehicle driver is low, 
further suggesting that requiring a camera field of view beyond 25 
degrees is unnecessary.
Agency Response
    The final rule does not include a short right curve scenario 
because NHTSA was persuaded by the comments.
    The reasons for this decision are similar to the reasons for 
modifying the measurement distances for the medium and large right 
curve scenarios. As explained earlier, NHTSA concluded that 
contemporary lower beams--especially beams that score well on the IIHS 
test--would likely not comply with the oncoming glare limits at 
distances corresponding to horizontal angles greater than 3 degrees--
that is, on a 100 m right curve, distances greater than 30 m (the 
distance at which the fixture would cross 3 degrees). This is 
consistent with the IIHS data submitted by SAE, which shows that none 
of the lower beams tested were within the oncoming glare limits between 
60 and approximately 120 m, and most of the lower beams tested were not 
within the oncoming glare limits from 30 m to 60

[[Page 9967]]

m. (From 15 m to 30 m, almost all the lower beams tested by IIHS were 
within the glare limits.) As such, the agency has confidence that 
including a small radius right curve scenario would have no positive 
impact on safety relative to that provided by current lower beams in 
this situation.
    Because, as explained above, the final rule specifies right curve 
scenarios only for measurement distances corresponding to horizontal 
angles to the left of 3R, this would leave only about 15 m of track 
length (and 1 second of test time) for this scenario. NHTSA concluded 
it was not useful to include such a short-duration scenario in the 
final rule.
9. Other Test Parameters and Conditions
a. Radius of Curvature
    NHTSA proposed testing using a curved path scenario (both left and 
right curves) with a variety of radii of curvature. The NPRM proposed 
testing on a ``small'' curve with radii of curvature from 98 m--116 m 
(320-380 ft); a ``medium'' curve with radii of curvature of 223 m-241 m 
(730-790 ft); and a ``large'' curve, 335 m-396 m (1100-1300 ft). The 
NPRM proposed that the curve on which testing is conducted be of a 
constant radius within the range listed in the test matrix.
Comments
    Manufacturers requested clarification or modification of the 
specifications and procedures related to the radius of curvature.
    The Alliance, Ford, and Toyota commented on measuring the radius of 
curvature. Ford requested clarification on how to measure the radius of 
curvature and all three commenters recommended following the IIHS 
protocol and measuring the radius of curvature from the center of the 
test vehicle's travel lane.
    Toyota suggested the final rule not specify a constant radius 
because it is not practical and is rarely the case in real-world 
situations.
    Honda, Toyota, and Auto Innovators requested clarification of the 
direction of curvature (left or right).
    OICA, SAE, SMMT, and Auto Innovators commented that the proposed 
road geometries do not exist at the proving grounds of many vehicle 
manufacturers. Auto Innovators commented that its testing contractor 
found that modifications to curvature radii were necessary to 
accommodate performance of the specified test scenarios at its 
facility, and that only the short-radius curve was within the NPRM 
specification.
Agency Response
    NHTSA has made a variety of changes in the final rule in response 
to these comments. With respect to measuring the radius of curvature, 
the final rule adopts regulatory text to specify that the curve is of a 
constant radius, as measured to the centerline of the path on which the 
test vehicle travels, within the range specified in the test matrix. In 
its latest testing, NHTSA used an inertial navigation system to follow 
a pre-programmed path for the centerline of the vehicle to follow. This 
was executed using a steering controller that followed the predefined 
path.
    When conducting its compliance testing, the agency may choose any 
radius within the range listed in the test matrix. The constant-radius 
specification is intended to indicate that the agency does not intend 
to test on compound curves (i.e., a curve with a non-constant radius of 
curvature). Considering that the manufacturer must certify that the 
vehicle will perform throughout the range of radii of curvature 
specified in the test matrix, NHTSA does not expect dramatic 
differences in results if the radius is not perfectly constant but 
contains minor variations throughout the run. The final rule also 
retains ranges for the radii of curvature, as opposed to a single 
radius of curvature with a relatively narrow tolerance. NHTSA believes 
the system should be able to function over at least these range of 
radii because they are representative of real-world roadway geometry.
    NHTSA agrees with Honda and Toyota about clearly specifying the 
direction of curvature and has done so in the regulatory text.
    With respect to the comment that the specified curves are not 
available at testing facilities, NHTSA was able to test on the curves 
specified in the final rule at the Transportation Research Center (TRC) 
Vehicle Dynamics Area (VDA). This test facility is publicly available 
to manufacturers.
    The final rule slightly modifies the specifications for the radii 
of curvature for all curves. NHTSA converted the center of the proposed 
range units from feet to meters and rounded the meter units.
b. Test Vehicle Speed and Acceleration
    The NPRM proposed, for each test scenario, a range of test vehicle 
speeds that NHTSA could select. The values proposed for speed, radius 
of curvature, and superelevation were 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] TR22FE22.031

where f is the coefficient of friction, V is the vehicle speed, R is 
the radius of curvature, and e is superelevation.\142\ The speeds 
ranged from a high of 70 mph for the straight scenario to 25 mph for 
the short-radius curve scenarios.
---------------------------------------------------------------------------

    \142\ See A Policy on Geometric Design of Highways and Streets. 
American Association of State Highway and Transportation Officials. 
Washington, DC (2011) (AASHTO Green Book), pp. 3-19 to 3-20.
---------------------------------------------------------------------------

    The NPRM proposed that for each test run, a speed conforming to the 
ADB test matrix would be selected and that the test vehicle would 
achieve this speed  0.45 m/s (1 mph) prior to reaching the 
data measurement distance and maintain this speed with ``no sudden 
acceleration or braking.''
Comments
    SAE, Toyota, and Honda recommended that, to simplify the test and 
reduce variability, the final rule specify a specific vehicle speed and 
tolerance for each scenario. Auto Innovators recommended that the 
maximum test speed be reduced from 70 mph to 55 mph because camera 
detection does not depend on vehicle speed; the majority of fatal 
nighttime crashes on curves occur at speeds of 55 mph or less; and 
certain vehicles (such as large trucks) would have difficulty reaching 
the specified test speeds given the lengths of courses available at 
test facilities. Toyota suggested providing a more specific 
specification for acceleration.
Agency Response
    The final rule retains the speed ranges and tolerances proposed for 
each scenario. The range of speeds reflects the real world (where 
different drivers may take the same curve at different speeds) and 
provides testing flexibility.

[[Page 9968]]

    The speeds set out in the final rule are generally higher than 
specified in SAE J3069, which states that ``[t]he speed of the vehicle 
for the full length of the 155 m test shall be above the ADB activation 
threshold of the vehicle as specified by the manufacturer.'' \143\ 
NHTSA believes that testing at speeds only marginally higher than the 
activation speed would not be representative of real-world driving, 
especially on the types of roads and situations (e.g., outdriving lower 
beam) in which ADB is most useful. The ADB systems NHTSA tested had 
activation speeds ranging from 19 to 43 mph.\144\ Safety concerns 
regarding glare, like many safety concerns, are also magnified at 
higher speeds.
---------------------------------------------------------------------------

    \143\ 5.5.6.1.
    \144\ 2015 ADB Test Report, p. 20.
---------------------------------------------------------------------------

    NHTSA disagrees with the suggestion that test speed does not impact 
ADB system performance, as the higher the test speed, the quicker the 
system must identify and shade the fixture. The proposal did not 
specify test speeds greater than 55 mph on curves; speeds above this 
were only proposed for straight-path scenarios. Regarding the concern 
that vehicles such as large trucks may have difficulty attaining test 
speeds in the distances available at track test facilities, the final 
rule specifies test fixtures and not stimulus vehicles, which should 
facilitate testing at the higher speeds. Further, the agency was able 
to achieve the maximum test speed of 70 mph on two different sections 
of the TRC facility for the straight scenario, using a class 8 truck 
tractor in the loaded and unloaded condition on the skid pad and the 
vehicle dynamics area (this is the surface that was used for all of the 
research testing). While complete lamp testing was not conducted using 
the class 8 truck tractor, the pitch and speed parameters were recorded 
along the path to demonstrate that a valid test was possible. Given the 
superiority of full-vehicle testing of ADB, the difficulties that a few 
vehicles may have in executing the test procedure do not appear 
insurmountable for heavy vehicles.
    Regarding Toyota's comment on the acceleration criteria, the 
proposal did address acceleration beyond the specification that ``no 
sudden acceleration or braking shall occur'' in that it also specified 
a tolerance of +/- 0.45 m/s (1 mph) for the nominal test speed. This 
tolerance is smaller than that used in the IIHS test procedure (3 km/h 
(.83 m/s)). In NHTSA's testing, the test driver was able to 
consistently maintain the speed within this tolerance. In addition, the 
final rule includes a vehicle pitch allowance that constrains 
acceleration in that if acceleration causes changes in vehicle pitch 
exceeding 0.3 degrees compared to the average pitch, then the measured 
illuminance at those points will not be considered in determining 
compliance.
c. Headlamp Aim
    The proposed test procedures specified several aspects of test 
vehicle preparation. This included that the headlamps would be aimed 
and the ADB system adjusted according to the manufacturer's 
instructions.
    FMVSS No. 108 requires that when a headlamp is installed on a motor 
vehicle, it must be aimable.\145\ The standard specifies compliance 
options for the aiming system. The principal options are vehicle 
headlamp aiming devices (VHAD) and visual/optical aiming devices 
(VOA).\146\
---------------------------------------------------------------------------

    \145\ S10.18.
    \146\ The standard specifies a third compliance option 
(mechanical aim), which involves an externally-applied mechanical 
device. This method is no longer in use and is not at issue in this 
rulemaking.
---------------------------------------------------------------------------

    A VHAD is an item of equipment installed on the vehicle and 
headlamp which is used for aiming the headlamp mechanically, such as 
with a bubble vial on the headlamp housing which has a closely 
specified geometric relationship to the headlamp beam's vertical 
location. A similar mechanical reference marking system is used for 
correct horizontal aim, essentially aligning the optical axis of the 
headlamp housing or reflector to the vehicle's longitudinal axis.
    VOA involves either projecting the beam onto a vertical surface and 
then adjusting the headlamp to an appropriate position as determined by 
an observer (visual aim), or projecting the beam into an optical device 
that is placed in front of the headlamp and then adjusting the headlamp 
until the beam conforms to the appropriate parameters (optical aim). 
VOA is used on most, if not all, vehicles currently sold in the U.S. 
The standard requires a relatively sharp horizontal cutoff in the lower 
beam pattern in order to aim the headlamps vertically. The standard 
does not permit horizontal aiming on VOA headlamps unless the headlamp 
is equipped with a horizontal VHAD.
Comments
    IIHS expressed concern that the NPRM allowed vehicle manufacturers 
to provide headlamp re-aiming procedures and ADB adjustments prior to 
testing, because for the systems to be effective in real-world driving, 
they need to function without adjustment when the consumer purchases 
the vehicle. IIHS explained that its headlighting system evaluations 
are conducted without changing the factory aim of the headlamps. They 
found that there is often a wide range of aim values between 
manufacturers, between some vehicles of the same make and model, and 
even between the left and right headlamp of the same vehicle, 
indicating that ADB effectiveness will be reduced if there is no 
incentive in the regulation for precise aiming at the factory. IIHS 
noted that this is even more important for ADB than for traditional 
headlighting systems since both the headlamps and the camera system 
require accurate alignment. IIHS further stated that just as NHTSA 
would not allow manufacturers to modify an air bag deployment algorithm 
prior to conducting FMVSS No. 208 compliance crash tests, the agency 
should not allow the ADB system to be modified to a condition that may 
not exist on any other production vehicle. IIHS provided data on 
factory aim variation for seven new vehicle models with VOR headlamps 
showing that most had aim values that would have a substantial effect 
on the measured visibility distances in the IIHS evaluation. IIHS 
stated that this indicates that conducting headlamp evaluations or 
compliance testing with re-aimed lamps is likely to reduce the real-
world relevance of the tests.
    Conversely, several commenters (Valeo, the Alliance, Volkswagen, 
SAE, Koito, Global, Honda, Auto Innovators, and Ford) requested that 
the final rule allow for horizontal aim adjustment on VOA ADB headlamps 
without equipping them with a horizontal VHAD (as the standard 
currently requires). The commenters highlighted the importance of 
horizontal aiming for ADB systems and requested that the final rule 
allow horizontal aim adjustment on VOA headlamps used in conjunction 
with an ADB system. They stated that in order to maximize the 
visibility benefits of ADB, the area of reduced intensity must be 
minimized, which can only be accomplished using both horizontal and 
vertical aiming. They commented that horizontal adjustment of the beam 
is critical in placing the area of reduced intensity accurately over 
the oncoming or preceding vehicles. If a horizontal aim access 
allowance were not incorporated into the final rule, automakers would 
be required to compensate for the expected horizontal vehicle variation 
into the size of the area of reduced intensity, resulting in greatly 
increasing this area, and lessening the additional light.
    The commenters noted that the standard prohibits horizontal aim on 
a

[[Page 9969]]

VOA headlamp unless a VHAD is provided, and stated that VHADs are 
unreliable, ineffective, lack the accuracy necessary for use with ADB 
systems, and are essentially obsolete. SAE suggested that NHTSA modify 
the current regulatory text in S10.18 and S14.2.5 to allow headlamps 
with adaptive driving beams to be adjusted according to the 
manufacturer's instructions.\147\ Auto Innovators commented that the 
method to horizontally aim ADB headlamps varies depending on the 
specific execution of the ADB system. Each involves an ADB-specific aim 
calibration mode to be activated either by a dealer or consumer when 
the vehicle is parked. This mode illuminates a horizontal aim feature 
utilizing one or more of the ADB-illuminated elements which have a 
sufficient vertical gradient that can be used for horizontal aim, just 
as one does today with vertical aim. The dealer or consumer would use 
this vertical gradient to properly calibrate the horizontal aim 
following instructions specified in the service manual or owner's 
manual.
---------------------------------------------------------------------------

    \147\ Ford noted that NHTSA has opined that horizontal aiming is 
permitted with VOA headlamps provided it is disabled or made 
inaccessible for consumers, but contended that this does not address 
the potential need for re-adjustment should the ADB system need to 
be aimed after sale to the consumer (for example, upon headlamp 
replacement due to vehicle damage).
---------------------------------------------------------------------------

    Several of these commenters pointed out that the ECE and Canadian 
requirements provide for horizontal aim with VOA headlamps and that 
effectively requiring horizontal VHADs would drive hardware 
disharmonization. Ford pointed out that SAE J3069 recognized the 
necessity of horizontal aiming for ADB systems, and that Canada, in 
adopting SAE J3069, specifically permitted horizontal aim.
    ALNA suggested applying tolerances for aiming the headlamps.
Agency Response
    The final rule follows the proposal and specifies that the 
headlamps will be aimed and the ADB system adjusted according to the 
manufacturer's instructions. In addition, the final rule provides that 
the test vehicle will be loaded within +/- 5 kg of the total vehicle 
weight during track testing prior to aiming the ADB headlamps. This is 
intended to indicate that NHTSA will not change the loading of the 
vehicle by more than 5 kg compared to what it is when the headlamps are 
aimed. This means that NHTSA will not aim the headlamps when the 
vehicle is at a lower weight compared to when the vehicle is fully 
instrumented and occupied by a test driver (which changes the pitch of 
the vehicle, and thus, the aim of the headlamps).
    NHTSA disagrees with IIHS and believes that manufacturers should be 
permitted to specify aiming procedures prior to the compliance tests. 
IIHS's suggestion is essentially that on-vehicle aim should be 
regulated. Even if this approach may have merit, it is outside the 
scope of this rulemaking, which extends the current requirements to ADB 
systems. The proposed specification is also consistent with the 
required laboratory testing, which involves aiming the headlamp prior 
to testing. Conventional laboratory testing of headlamps has long 
permitted aiming them prior to testing. This contributes to the 
repeatability of the test and sets a consistent standard to which 
headlamps must perform. This is important because the laboratory 
photometric requirements are the basis for the current track-based test 
procedure limits; if we were to consider practical limits that included 
variations in aim introduced through the distribution chain, the limits 
that are finalized might not be appropriate. In addition, as IIHS 
notes, ADB systems rely on accurate alignment of the headlamps and 
camera systems. Aiming the headlamps prior to the compliance test 
limits aim variation and isolates ADB performance. This approach 
ensures that the ADB compliance test will be performed with a 
headlighting beam pattern that, as manufactured, at least meets a 
minimum level of performance. The end customer or dealer can then aim 
the headlamps to align the system appropriately.
    The agency agrees that successful implementation of ADB using 
current technology requires the regulation to provide flexibility to 
permit headlamps to be aimed horizontally once installed on the vehicle 
to align the vehicle, camera, and headlamps. As explained below, while 
NHTSA agrees with the commenters that ADB systems should be exempt from 
several of the current requirements for horizontal VHADs, NHTSA does 
not agree that ADB-equipped VOA headlamps should be completely exempt 
from all the VHAD requirements.
    FMVSS No. 108 does not permit VOA headlamps to be visually aimed 
with respect to horizontal aim. NHTSA explained the reason for this in 
the 1997 final rule that permitted VOA aim headlamps.\148\ Because the 
lower beam of a headlamp designed to conform to Standard No. 108 does 
not have any visual cues for achieving correct horizontal aim when 
aimed visually or optically, and because it is not possible to add such 
visual features without damaging the beam pattern, horizontal aim 
should be either fixed and nonadjustable, or have a horizontal VHAD. 
The agency also noted that the negotiated rulemaking committee involved 
in that 1997 negotiated rulemaking ``considered features for horizontal 
visual/optical aiming but none were deemed sufficiently developed and 
designed to be usable.'' \149\ Accordingly, that final rule did not 
permit any horizontal movement of VOA headlamps, with the lamp 
essentially being correctly aimed as installed, unless the headlamp was 
equipped with a horizontal VHAD. The horizontal VHAD was included as a 
compliance option (and required to be set to zero) as a means for 
manufacturers to meet European requirements for both a horizontal and 
vertical aim adjustment. For these reasons, in 1999 NHTSA denied a 
petition for rulemaking to allow VOA headlamps to have a horizontal 
adjuster system that does not have the required 2.5-degree horizontal 
adjustment range or a VHAD indicator.\150\
---------------------------------------------------------------------------

    \148\ 62 FR 10710 (Mar. 10, 1997).
    \149\ Id., p. 10715.
    \150\ 66 FR 42985 (Aug. 16, 2001) (denial of rulemaking petition 
from Federal-Mogul Lighting Products).
---------------------------------------------------------------------------

    Although VHADs are not widely (if ever) used, NHTSA is not 
persuaded that a VHAD for horizontal aiming would not be feasible for 
ADB-equipped headlamps. The commenters did not present any information 
to show VHADs are necessarily incompatible with the aiming accuracy 
necessary for ADB systems. While VHAD devices used prior to the 
allowance of visual optical aiming in the U.S. may have been 
inaccurate, these limitations are not driven by the requirements placed 
on VHADs by the FMVSS.\151\ The minimum requirements in FMVSS No. 108 
for horizontal VHADs provide a floor below which accuracy cannot drop, 
but do not limit aiming accuracy.
---------------------------------------------------------------------------

    \151\ See S10.18.8.
---------------------------------------------------------------------------

    For example, the requirements in S10.18.8.1.2 that the VHAD include 
references and scales relative to the longitudinal axis of the vehicle, 
including a ``0'' mark and an equal number of graduations from the 
``0'' mark, limit neither precision nor accuracy. The horizontal VHAD 
need only be accurate enough to set at 0 in order to perform basic 
photometry testing in the lab. Other measurement cues (including more 
precise methods) may be used to more accurately aim the headlamps on 
the vehicle for the purposes of ADB functionality. The

[[Page 9970]]

regulation does not restrict this but allows the flexibility to 
customize such methods to accommodate any unique features present in 
any beam.
    Even if NHTSA were to agree with the commenters that VHADs were not 
optimal for ADB systems, the agency does not currently have, and the 
commenters did not provide, a workable alternative. For example, SAE's 
suggested amendments to S10.18 and S14.2.5 simply stated that ``if the 
headlamp is equipped with ADB, and has horizontal aim, it shall be 
adjusted according to the manufacturer's instructions.'' If the 
commenters sought allowance of horizontal VOA aim for ADB systems, they 
did not provide information on how this would work in practice. Unlike 
the lower beam pattern in Europe, where the lower beam pattern has a 
vertical cutoff component and uses VOA for horizontal aim, the U.S. 
lower beam pattern has no such required cutoff or other cues--meaning 
horizontal VOA in FMVSS No. 108 is not currently feasible.\152\ If the 
beam pattern were to include cues that could be used to visually aim 
the headlamps horizontally, such a procedure could be workable. Such 
procedures, however, have not been developed for the United States 
market for visual/optical horizontal aim of the headlamps, and they 
would need to include, among other things, a cut-off requirement 
analogous to the current requirements for the horizontal cutoff for the 
lower beam.\153\ In addition, such requirements would limit the 
flexibility of beam pattern design currently permitted by the standard. 
This could limit the potential for innovative safety solutions 
generally afforded by this final rule. On the other hand, if the 
commenters referred to non-VOA methods, they were not presented to the 
agency.
---------------------------------------------------------------------------

    \152\ The ECE horizontal aim test procedure is in R112 Annex 9. 
This procedure is not suitable for headlamps in the U.S. because it 
relies on features in the beam pattern, such as the kink, that are 
not required to be present in a lower beam pattern by FMVSS No. 108.
    \153\ See S10.18.9.1.
---------------------------------------------------------------------------

    NHTSA agrees, however, that several of the requirements for 
horizontal VHADs (in S10.18.8.1.2.1-4) are not necessary for ADB 
systems. S10.18.8.1.2.1 requires that each graduation must represent a 
change in the horizontal position of the mechanical axis not greater 
than 0.38[deg] (2 in at 25 ft) to provide for variations in aim at 
least 0.76[deg] (4 in at 25 ft) to the left and right of the 
longitudinal axis of the vehicle, and must have an accuracy relative to 
the zero mark of less than 0.1[deg]. As the commenters alluded to, this 
minimum accuracy of graduation is likely not adequate for aligning the 
camera and headlamps. NHTSA expects that a more accurate method will be 
utilized to align the lamps and the camera and does not expect this 
alignment procedure to be manually conducted by non-expert vehicle 
owners. Similarly, S10.18.8.1.2.2-3 pertain to the readability of those 
graduations. S10.18.8.1.2.4 specifies minimum horizontal indicator and 
aiming ranges. Those limits are not relevant to ADB aim because they 
are intended to align the lamp with the vehicle, whereas ADB systems 
require the alignment of the lamp with the camera. NHTSA expects that 
this alignment range will be determined by each manufacturer 
appropriate for their camera installation and body tolerances. 
Consequently, the final rule exempts ADB systems from these 
requirements.
    With respect to harmonization, the agency recognizes that VHADs add 
some additional cost, but the option to use a horizontal VHAD was 
actually intended to facilitate harmonization by giving manufacturers a 
way to meet both the ECE requirements (which require both a horizontal 
and vertical aim adjustment) and the U.S. requirements (which require 
only vertical aimability). A VOA headlamp intended for sale in both the 
European and U.S. markets would likely have a vertical aiming screw and 
a horizontal VHAD, while one intended for use only in the U.S. market 
need only provide for vertical adjustment.\154\ In practice, 
manufacturers wishing to sell essentially the same headlamp design in 
both markets, but not utilize a horizontal VHAD, would typically design 
a lamp with both a vertical and horizontal aiming screw, and lock out 
(or make inaccessible) the horizontal screw in the U.S.-market version.
---------------------------------------------------------------------------

    \154\ 66 FR 42985, 42986 (Aug. 16, 2001).
---------------------------------------------------------------------------

d. Road Surface
    The NPRM proposed several specifications related to the quality of 
the test track surface, including that the tests would be conducted on 
a dry, uniform, solid-paved surface; that the road surface have an 
International Roughness Index (IRI) measurement of less than 1.5 m/km; 
and that the test course surface be composed of concrete or asphalt. 
The proposal also included an allowance for momentary glare exceedances 
that might be related to, among other things, imperfections in the road 
surface. SAE J3069 specifies an identical IRI value and that the test 
course surface be uniform, straight, flat and represent a typical road 
surface.
Comments
    Intertek commented that the IRI is not simple to measure 
quantitatively and that requiring a road surface quality of 1.5 m/km 
will impose unnecessary restrictions on the test track. The commenter 
recommend instead using the SAE J3069 value of 3 m/km.\155\ Auto 
Innovators commented that, for its testing, longitudinal lane IRI 
measurements were within the NPRM specification, averaging near 0.475 
m/km, but that atypical IRI measurements across transverse lanes (east/
west) are unknown and may impact testing on curves.
---------------------------------------------------------------------------

    \155\ SAE J3069 JUN2016 states, in section 7.1, that it is 
recommended that the road have an IRI of less than 1.5 m/km, while 
the text accompanying Figure 5 states that the IRI should be less 
than 3. SAE J3069 MAR2021 corrects the text in Figure 5 to state 
1.5.
---------------------------------------------------------------------------

    ALNA commented that test ground conditions and variations should be 
reflected in the requirements and suggested applying tolerances in 
order to reflect variations such as ground unevenness. Toyota commented 
that the NPRM did not sufficiently define the test track conditions and 
that failure to do so would affect compliance test results.
Agency Response
    The final rule deletes the IRI specification. The purpose of the 
IRI specification was to limit angular changes between the vehicle and 
the illuminance meters throughout the test run. This was anticipated to 
provide a boundary limit for which a vehicle manufacturer could certify 
performance of its vehicle. In other words, the ADB system was not 
expected to perform to the limits specified in the NPRM on a bumpy or 
wavy road. However, during NHTSA's most recent testing, it was found 
that a more direct approach--pitch adjustment--could be used to limit 
this orientation. IRI values are a general measurement of road 
roughness, but, in the context of the track test in this rule, are 
essentially a proxy for vehicle pitch: A test conducted on a test track 
surface with a low IRI will generally have less pitch variation than a 
test conducted on a surface with a high IRI. Directly measuring vehicle 
pitch eliminates the need for the IRI parameter.
    NHTSA believes that directly accounting for vehicle pitch addresses 
Auto Innovators' concern that the transverse IRI may influence test 
results (by influencing vehicle pitch, which in turn influences test 
results) on curve scenarios. The area of the test facility that NHTSA 
used for its most recent

[[Page 9971]]

testing had an IRI of 1.46 m/km in the EW direction and an IRI of 1.61 
m/km in the NS direction. In conducting its testing, however, NHTSA 
nested the straight, right, and left curves of each radius on the TRC 
VDA large-area test facility. As such, those IRI measurements are not 
direct measurements of the longitudinal or transverse paths taken 
during ADB testing. While the final rule limits the number of 
scenarios, it retains 6 different curved-path scenarios, including 
various radii for right and left curves. These paths may have slight, 
but potentially meaningful, differences in longitudinal IRI. While this 
longitudinal test surface roughness measurement is possible along each 
path, requiring a new IRI measurement any time the path is altered 
would be unnecessarily burdensome, considering it is possible to 
instead directly measure vehicle pitch. Additionally, the IRI can 
change over time, especially considering large temperature changes; it 
is possible that a path that in one season is under 1.5 m/km will 
exceed that value in a different season. Replacing the IRI parameter 
with a procedure for directly measuring and limiting the pitch 
variation of the test vehicle eliminates these concerns.
    With respect to the comments by ALNA and Toyota, the commenters did 
not identify specific additional ways to specify the test conditions. 
For the reasons given here and elsewhere in the preamble, NHTSA 
believes the final rule sufficiently accounts for test surface 
conditions to control for the major sources of testing variability--
including vehicle pitch--related to the test track.
e. Ambient and Reflected Light
    The NPRM proposed to control for ambient and reflected light, which 
can interfere with test results, in a few ways.\156\ Ambient 
illumination recorded by the photometers must be at or below 0.2 lux; 
testing must be conducted on dry pavement, and with no precipitation; 
the test road must be free of retroreflective material; and the 
pavement must not be bright white (to avoid intense reflections). 
Notwithstanding such controls, some degree of ambient light is 
unavoidable. Accordingly, in testing for compliance the agency proposed 
to zero-calibrate the photometers. SAE J3069 similarly specifies that 
the test track does not contain retroreflective material and that 
testing be conducted during clear weather on dry pavement.
---------------------------------------------------------------------------

    \156\ Ambient light refers to light emitted from a source other 
than the ADB system. This may include moonlight, light pollution 
from nearby buildings, or light coming from the test fixture itself. 
Reflected light refers to light from the ADB vehicle's headlamps 
reflected off the road or other surfaces (including rain or fog 
droplets) onto the photometric receptors.
---------------------------------------------------------------------------

Comments
    Intertek tentatively agreed with NHTSA's assessment of the impact 
of stray and ambient light on the test. Some commenters, however, 
stated that the proposal did not sufficiently control for ambient 
light. The Alliance and Volkswagen commented that ambient light can 
change throughout the data collection (e.g., due to clouds, the moon) 
during a test, which could introduce uncontrolled variability and 
difficulty in repeatability and reproducibility of test results. ALNA 
suggested applying tolerances for variations in test course surface 
conditions including ground reflectivity.
    Volkswagen commented that the presence of reflectors in the 
environment could cause test results to vary and that the NPRM did not 
address environmental conditions such as fog, dust, or pollution which 
exist in real-world testing and can introduce variability that will 
present challenges for repeatability and reproducibility. Mobileye 
commented that the track test requirements should specify that fog and 
dust should not be present when performing testing. TSEI recommended 
the agency clarify how ambient conditions should be treated.
Agency Response
    The final rule adopts the proposed test procedures, but modifies 
the photometer zero-adjustment procedure to reflect the fact that the 
test uses fixtures, not stimulus vehicles. The meters will continue to 
be zero-calibrated for each scenario tested.
    With respect to the comment about ambient light changing throughout 
the test, NHTSA found that the ambient light did not change 
significantly during a test session. Further, NHTSA's testing method 
accounted for ambient conditions by measuring ambient illuminance 
either immediately before or after each test trial and subtracting that 
value from the recorded test data. The repeatability analysis, which 
included testing on different nights, showed that the night on which 
testing occurred did not appear to be a significant source of 
variation. The commenters did not recommend any alternative methods to 
account for ambient or reflected light. SAE J3069 does not specify how 
ambient conditions or reflected lighting are to be treated aside from 
requiring that ``[n]o 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.'' \157\ Although 
the final rule does not specify a baffle, the regulatory text does not 
prohibit it if it provides more accurate results for a particular 
location. The agency did not study adding baffles in a systematic way 
because testing did not show stray light to be a significant 
contributor to variability.
---------------------------------------------------------------------------

    \157\ 5.5.2.1 and 5.5.3.1.
---------------------------------------------------------------------------

    With respect to reflectivity, as noted above, the proposal (and 
final rule) specifies that the test road be free of retroreflective 
material and that the pavement may not be bright white. With respect to 
tolerances, although the agency does not expect reflectivity to affect 
the illuminance measurements, the allowance for momentary exceedances 
would be applied to spikes in illuminance caused by any such factors. 
NHTSA is not aware of any standardized way of accounting for dust or 
fog, and the commenters did not identify any such method. In any case, 
the same test conducted on different nights did not lead to much 
variation in results. Certainly, if ambient environmental conditions 
were such that there was an unusual concentration of particulates--or 
any other unusual conditions that would be likely to affect test 
results--NHTSA would not attempt to conduct compliance testing. In 
addition, NHTSA's testing showed that the ambient light did not appear 
to fluctuate dramatically in the relatively short times it took to 
perform a test run. And, as noted above, the recorded test data was 
adjusted by subtracting the ambient illuminance. The agency therefore 
believes that test outcomes will generally not be affected by changes 
in ambient light.
f. Superelevation
    Superelevation refers to the degree of banking of a road. The NPRM 
specified that the test track have a superelevation of 0% to 2%. We 
explained that it was desirable to minimize the degree of banking 
because photometry design as well as the existing and derived glare 
limits are based on flat surfaces.
Comments
    Auto Innovators commented that it found that modifications to the 
specified superelevation were necessary to accommodate the track 
lengths at its test facility.
Agency Response
    The VDA test pad, on which NHTSA's most recent testing was 
conducted, has

[[Page 9972]]

a slope of 1% in the direction between the two loops. That means that 
the largest superelevation that we tested was less than 1%. The 
superelevation would be 1% had we tested across the width of the pad 
and 0% had we tested along the length of the pad. All the recent NHTSA 
tests were conducted somewhere between these two extremes. Accordingly, 
every test scenario traversed had a superelevation of less than 1% 
(based on the TRC site plan).\158\
---------------------------------------------------------------------------

    \158\ See TRC site plan at www.trcpg.com/wp-content/uploads/2016/10/Vehicle-Dynamics-Area.pdf last accessed on February 16, 
2021.
---------------------------------------------------------------------------

    We recognize that superelevation could, conceivably, influence test 
results.\159\ Depending on the details of the curve/fixture location, a 
large superelevation can either increase or decrease the likelihood 
that the measured illuminance will exceed the relevant glare limit. 
Superelevation effectively rotates the beam pattern around the 
centerline of the vehicle. If the rotation causes the pattern to rotate 
down with respect to the sensor location, it is less likely that the 
measured illuminance will exceed the glare limit; if, on the other 
hand, the rotation causes the pattern to rotate up with respect to the 
sensor location, the measured illuminance is more likely to exceed the 
glare limit. More specifically, on a left curve a positive 
superelevation will always make it less likely that the glare limit 
will be exceeded because the fixture is always on the left side of the 
beam pattern and the superelevation causes a rotation of the beam 
pattern counterclockwise. For the portions of a right curve at which 
the photometric receptors are to the left of the beam pattern, a 
positive superelevation will increase the likelihood that the measured 
illuminance will exceed the glare limit because the beam pattern is 
rotated clockwise for a positive superelevation on a right curve. 
Finally, for straight-path test scenarios, a large positive 
superelevation will always be more stringent because the ``crown'' in 
the road rotates the beam pattern clockwise and the fixture is always 
to the left.
---------------------------------------------------------------------------

    \159\ In addition, the wider the specified range of 
superelevation, the more stringent the test, because the vehicle 
must perform over a larger range of superelevation angles.
---------------------------------------------------------------------------

    We do not expect superelevation to have a meaningful impact on the 
test results, especially compared to the effect of vehicle pitch, which 
can materially impact test results. For this reason, we concluded that 
it was not necessary to include an adjustment for superelevation.
g. Lane Divisions
    The NPRM specified that the test track lanes may have a median of 
up to 6.1 m (20 ft) wide and should not have any barrier taller than 
0.3 m (12 in.) less than the mounting height of the stimulus vehicle's 
headlamps. SAE J3069 does not specify any lane divisions or medians but 
does specify that the test track area be free from obstructions and 
retroreflective markings.
Comments
    Mobileye commented that roads with narrow curves do not typically 
have such wide medians, and this will place the stimulus vehicle at a 
very wide angle to the host vehicle. Intertek questioned the need to 
consider medians or barriers and suggested that the median be limited 
to a standard lane divider. SL Corporation commented that a traffic 
barrier is not necessary and may make it difficult for ADB systems to 
accurately detect oncoming traffic, recommending that final rule 
provide a more detailed specification if retained. SAE questioned the 
inclusion of a 20-ft median for a 320-ft curve because medians of that 
size are typically found only on higher speed interstate roads which do 
not contain curves of that sharpness.
Agency Response
    NHTSA agrees with commenters that a median or barrier is not useful 
for testing. These features are not included in the final rule.
h. Hills
    The NPRM did not propose testing on sloped (dipped or hilly) roads, 
explaining that even headlighting systems 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 headlighting systems and FMVSS-compliant lower beams 
glared oncoming and preceding vehicles on roads with dips.\160\ NHTSA 
tentatively concluded that to require this performance of ADB systems 
would be neither practical nor consistent with the approach of this 
rulemaking (extending the existing lower beam glare requirements to ADB 
systems).
---------------------------------------------------------------------------

    \160\ 2015 ADB Test Report, pp. 102, 108, 114.
---------------------------------------------------------------------------

Comments
    AAA asserted that the track test should include scenarios with 
undulating roadways and hills but seemed to suggest that this might be 
limited to ADB systems with higher-intensity upper beams (i.e., at the 
ECE maximum). AAA commented that ADB technology has the ability to 
avoid glaring other drivers in these situations, and that including 
this in the test will create pressure to more quickly and successfully 
address this.
Agency Response
    The final rule does not include testing on dips or hills for 
several reasons. First, this approach would be more stringent than 
current requirements. Current lower beams create glare for other 
drivers on hills. The general approach of this rulemaking was to extend 
the current headlamp requirements to ADB systems, not to increase the 
stringency of existing requirements for ADB systems. Second, NHTSA's 
testing indicated that current ADB systems did not perform well on hill 
scenarios. Although including such scenarios in the track test could 
help speed the development of ADB systems with these advanced 
capabilities, it would likely make the systems more costly and slow 
deployment. Finally, NHTSA has not developed test procedures for such 
scenarios. This would take additional time and resources and would 
require developing a complex test track that would be specific to ADB 
testing. However, while it is outside the scope of the current 
rulemaking to test ADB systems to ensure that they produce less glare 
than current headlamps, NHTSA intends to monitor this issue and will 
consider future action if warranted.
10. Data Acquisition and Measurement
a. Photometers
    The proposed regulatory text specified that the photometer must be 
capable of a minimum measurement unit of 0.01 lux.
Comments
    Intertek suggested specifying that the photometric receiver have a 
cosine response and be spectrally matched to the photonic response of 
the human eye. It also suggested an accuracy limit of +/- 5% nominal 
over the full range of illuminance from 0.01 lux to the upper limit 
(about 100 lux).
Agency Response
    NHTSA's testing utilized a Minolta T10A illuminance meter. The 
manufacturer's specifications indicated that it has a spectral response 
within 6% of the (CIE) human eye photopic vision [V([lgr])] and a 
cosine correction characteristic within 3%. The photometers used in 
agency research

[[Page 9973]]

were capable of measuring light within 3% of the ideal cosine response. 
NHTSA agrees with Intertek's suggestion and has modified the regulatory 
text to include photometer specifications drawn from S14.2.5.7.3 and to 
specify a cosine response within 3%.
    The agency also notes that the IIHS headlamp testing procedures 
\161\ used baffles on the photometry equipment at 25 degrees to ensure 
that the light captured was more directly attributable to the test 
vehicle light source, and not to stray lighting that may be captured by 
the photometer. This 25-degree angle is roughly equivalent to the 
angles of incidence of light received from the light source when the 
test vehicle is approaching the stimulus through a curve on the roadway 
surface and equates to the angles at which ADB systems are typically 
scanning for targets to shade. NHTSA finds the IIHS test method 
specifications closely match our intent and has adopted similar 
language to include a 25-degree angle of incidence.
---------------------------------------------------------------------------

    \161\ See supra note 93.
---------------------------------------------------------------------------

b. Sampling Rate
    The NPRM proposed to sample illuminance at a rate of at least 200 
Hz. SAE J3069 specifies a sampling rate of 10 Hz, and IIHS test methods 
sample illuminance at 200 Hz.
Comments
    Volkswagen commented that sampling at 200 Hz would lead to a more 
complex selection of measuring equipment and analysis for each 
experiment and supported the SAE J3069 specification. Global requested 
that NHTSA explain the appropriateness of this minimum sampling rate 
and whether a maximum sampling rate should be specified.
    Intertek commented that 200 Hz is near or exceeding the capability 
of most high-grade light meters and recommended reducing the sampling 
rate to 100 Hz in order to resolve illuminance in the ranges necessary 
for this test. Intertek also stated that reducing the sampling time to 
100 Hz is supported by the allowance of momentary exceedances up to 0.1 
seconds in duration (100 Hz would include 10 measurements within that 
0.1 seconds) and suggested determining acceptance based on a time-
averaged sampling rate at 10 Hz to account for very fast variances in 
the illuminance level as well as the human eye response.
Agency Response
    After considering the comments, the final rule adopts a sampling 
rate of at least 100 Hz. NHTSA is balancing the need for precise data 
collection with the cost and availability of equipment. NHTSA agrees 
that 200 Hz is faster than the minimum needed to verify compliance, 
particularly considering the 0.1 second allowance, but the SAE sampling 
rate of 10 Hz simply provides too little data to ensure that ADB 
performance is within the specified glare limits. While a 200 Hz 
sampling rate matches that used by NHTSA in both its most recent 
research and in the research reported in the 2015 ADB Test Report (as 
well as that used by IIHS), and did not present any issues, NHTSA 
agrees with Intertek that a sampling rate as low as 100 Hz would 
provide adequate date collection to detect exceedances lasting near the 
0.1 s allowance. As described by Intertek, a 100 Hz data collection 
method collects 10 readings within 0.1 s. This is adequate to judge a 
short exceedance, and an extra 10 readings provided by a 200 Hz rate 
would not substantially change that ability. A sampling rate of 10 Hz 
however would collect only a single reading over 0.1 s, making it 
difficult to judge the actual time a short exceedance lasts. The agency 
considered adding a maximum sampling rate but does not believe doing so 
is necessary because the final rule specifies an allowance for 
momentary glare exceedances (up to 0.1 s) as well as a low-pass filter 
with a cutoff frequency of 35 Hz.
    NHTSA is not incorporating time-averaged sampling due to concerns 
that the delay associated with time-averaging would make it difficult 
to properly synchronize illuminance and distance. This is particularly 
important at higher vehicle speeds. Time-averaging (depending on the 
parameters) could also collect illuminance levels from one location 
over time and report that data at a moment while the vehicle is closer 
to the fixture. This would have the result of shifting illuminance 
levels down because all tests are arranged such that the vehicle 
approaches the fixture, and never moves away from it.
c. Noise and Filtering
    The NPRM did not specify any filters other than the 0.1 s or 1m 
spike allowance, and the proposal did not explore this issue although 
it sought comment on it. The IIHS test procedure does specify that 
photometric sensor signals be filtered through a low-pass filter with a 
cutoff frequency of 35 Hz. This allows for accurate measurement of all 
existing types of headlamp light sources, including pulse width 
modulated systems like LEDs. IIHS test methods sample illuminance at 
200 Hz, and any ambient offset for the measurements is based on the 
minimum ambient illumination from 1-5 seconds after the test vehicle 
has passed the measurement location.
Comments
    Global requested that the agency clarify which standards OEMs will 
be permitted to use when removing test data noise from measured data, 
and suggested incorporating any such standards in the final rule or the 
formal compliance test procedure (NHTSA understands this to refer to 
the laboratory test procedure, which is not part of the regulatory text 
but is published separately by the Office of Vehicle Safety 
Compliance). Intertek suggested that to ensure that all the energy is 
accounted for, the minimum data acquisition rate should be 100 Hz, and 
the data should be subject to averaging or boxcar smoothing to reduce 
the effective sampling rate to a frequency of 10 Hz. Intertek 
alternatively suggested an integrating photometer with a period of 100 
ms. The final product would then be the filtered illuminance (with PWM, 
pitch, and other sources of noise averaged out) reported with a 
frequency of 10 Hz (or another frequency such as 25 or 33 Hz based on 
the human eye response), or if boxcar averaging, it could be reported 
at 100 Hz (with the understanding that each measurement carries 10 Hz 
of averaging).
Agency Response
    In response to Global's request, the final rule specifies that 
NHTSA will use a low-pass filter with a 35 Hz cutoff frequency.\162\
---------------------------------------------------------------------------

    \162\ As NHTSA has pointed out in the past, the FMVSS specify 
the procedures NHTSA will use in compliance testing. While 
manufacturers must exercise reasonable care in certifying that their 
products meet applicable standards, they are not required to follow 
the compliance test procedures set forth in a standard.
---------------------------------------------------------------------------

    The low pass filter essentially reduces high-frequency noise by 
adjusting each data point by comparing it to the average of the 
neighboring data. Any individual points that are higher than the 
immediately adjacent points are reduced, and any points lower than the 
immediately adjacent points are increased. As long as the general data 
trends in the underlying signal are true (low frequency--allowed to 
pass), then the signal will not be distorted by smoothing. This filter 
is suitable for the types of measurements collected as it

[[Page 9974]]

results in the most complete response to noise without detrimental 
effects on the data. Because the noise effects are assumed to be evenly 
distributed with a standard deviation (d), the noise remaining in the 
measurements will be approximately d over the square root of the smooth 
width (m) of 35 samples at the 100 Hz we are collecting data. At the 
finalized low-pass filter rate, that reduces the noise to less than 
0.03 of the standard deviation of the noise in the lux. Filtering will 
not eliminate the measurement noise and will result in a slight 
reduction of the peak lux values measured during the track test. The 
agency does not expect this to affect test results, however, both 
because the reduction in the peak value is limited by the higher 
sampling rate (100 Hz versus 10 Hz for SAE) and because even at the 
broad width of the smoothing filter, the filter only smooths values 
over roughly a third of the ``sudden spike'' timing, allowing for 
differentiation of a spike from a non-compliance.
    The box-car averaging has the advantage of filtering out both 
signal and test condition noise. Such data treatment is useful for 
smoothing rapidly changing signal data, such as that type of data that 
may result from vibratory effects as the test vehicle moves across the 
track test bed. It is essentially equivalent to using a low pass 
filter, as specified in the IIHS test procedure. The final rule is 
therefore consistent with Intertek's comments.
d. Allowance for Momentary Glare Exceedances
    The NPRM proposed an allowance for momentary glare exceedances (or 
``spikes'') of not greater than 0.1 second in duration or spanning 1 m 
of vehicle travel. This was intended to account for variations in 
illumination due to uncontrolled testing variables, such as minor 
imperfections in the road surface.\163\ Minor imperfections in the road 
surface can cause glare exceedances by affecting vehicle pitch.
---------------------------------------------------------------------------

    \163\ This is different from an allowance for an adaptation time 
(referred to as ``reaction time'' in SAE J3069) which we understand 
as referring to another possible reason for a testing allowance: To 
account for the operation of the ADB system itself, because, as the 
discussion in SAE J3069 points out, ``ADB cannot react 
instantaneously.'' This is discussed in Section VIII.C.5 above.
---------------------------------------------------------------------------

Comments
    Some commenters believed the proposed allowance was insufficient. 
Toyota stated that the requirements to minimize glare go beyond the 
levels currently specified in the standard and beyond what is needed to 
meet a safety need and that, given the strict allowance for momentary 
glare, additional test parameters would need to be defined; for 
example, the vehicle pitch can vary (due to the condition of the road, 
suspension, tires, and the vehicle's acceleration), potentially 
affecting the compliance result. Similarly, SAE and Volkswagen 
commented that a 0.1 second allowance is insufficient, would frequently 
be exceeded even by compliant lower beams (for example, due to 
momentary changes in vehicle pitch), and it would be unreasonable to 
expect an ADB system to comply with the glare limits in the numerous 
proposed test scenarios with only that allowance. Auto Innovators 
proposed that NHTSA increase this allowance to 2.5 seconds, based on 
the human response time to the sudden appearance of an opposing or 
preceding vehicle. ALNA agreed that it is appropriate to apply 
tolerances in order to cover on-road application and reflect variations 
in test ground conditions.
    SAE, Global, Ford, and the Alliance stated that in order to account 
for otherwise uncontrolled-for test variability, NHTSA should follow 
SAE J3069 such that the glare limits may be exceeded if the ADB 
illuminance does not exceed 125% of the lower beam illuminance from the 
vehicle measured under the same conditions. SAE, Global and Ford 
commented that this better represents real-world conditions and 
compensates for environmental factors such as dips and bumps in the 
road, reflectivity of lane markers, ambient light, and vehicle pitch.
    Global commented that the term ``spike'' is not defined and 
recommended that it be defined relative to accommodating the natural 
behavior of certain headlamp light sources to have a ``spike'' of light 
intensity during the sequence of use.
    Global also pointed out that in the proposed regulatory text (``no 
longer that 1 meter'') ``that'' should be replace with ``than.''
    Auto Innovators commented that the distance exceedance limit should 
be eliminated because specifying both a time and distance specification 
is duplicative, and timing is more relevant to real-world driving.
Agency Response
    The final rule retains the 0.1 second component of the momentary 
glare exceedance allowance and adds (as discussed in the next section) 
an allowance for vehicle pitch.
    The momentary glare exceedance allowance accounts for testing-
related variability caused by noise and uncontrolled test factors (such 
as uncontrolled ambient illuminance).\164\ NHTSA believes that 2.5 
seconds is an inordinately long time for a ``momentary'' exceedance, 
for the reasons discussed earlier.\165\ The agency also declines to 
follow SAE J3069 and allow ADB illuminance to exceed lower beam 
illuminance by up to 25%. The reasons for this are discussed in Section 
VIII.C.4, Maximum Illuminance Criteria (Glare Limits). NHTSA agrees 
with Global that there was a typographic error in the proposed 
S14.9.3.12.8.1 (now at S14.9.3.12.2), which has been corrected in the 
final rule. The agency also agrees that even at the slowest test speed 
of 25 mph the limiting factor is time, not distance, and has removed 1 
m from the text as it serves no practical purpose.
---------------------------------------------------------------------------

    \164\ NHTSA, in its testing, did not observe any test-related 
variable other than pitch that led to a glare exceedance. While some 
limited glare exceedances lasting less than 0.1 seconds were not 
caused by pitch, these appeared to result from marginal performance 
from the ADB system. The 0.1 second allowance means that such 
exceedances would not be considered a noncompliance.
    \165\ See Section VIII.C.5, ADB Adaptation Time.
---------------------------------------------------------------------------

    NHTSA is removing the term ``spike'' and replacing it with a 
clearer description of the adjustment: The agency will not consider, in 
determining compliance, ``single illuminance values or consecutive 
illuminance values occurring over a span of no more than 0.1 seconds 
that exceed the applicable maximum illuminance[.]'' The momentary glare 
exceedance duration may end in at least two ways. First, the 
illuminance value can drop below the applicable glare limit. Second, 
the glare limit itself might change (i.e., increase). This could happen 
if the exceedance is experienced just before the glare limit changes. 
In either case, if the glare limit is not exceeded for more than 0.1 s, 
the exceedance will not be considered a noncompliance.
e. Vehicle Pitch
    Pitch refers to rotation of a vehicle about its transverse axis 
appearing as an opposing vertical motion of the front and rear ends of 
a vehicle. When a vehicle's pitch increases, the vehicle's front end, 
and therefore the angle of its headlamps, will raise in an upward 
direction away from the road surface. Conversely, when pitch decreases, 
the vehicle's front end will lower, and the headlamps light will be 
cast downward towards the road surface.
    The amount of glare perceived by other roadway users may be more 
pronounced when the headlamp is pitched upward. Common causes of 
changes in vehicle pitch angle include vehicle loading condition or 
weight

[[Page 9975]]

distribution, tire inflation that deviates from specifications, 
irregularities or pitting in the road surface, vehicle suspension 
characteristics, and vehicle acceleration. As mentioned above, the NPRM 
did not propose any adjustments to correct directly for or take vehicle 
pitch into account as part of the compliance track testing, although it 
specifically sought comment on this.
    In the IIHS test method, pitch effects are corrected by measuring 
road surface pitch changes through a self-leveling horizontal rotary 
laser system every 5 m along the test track surface. The pitch angles 
at each measured position are measured, and photometers placed at 
different heights provide the illuminance data for each measurement 
location. Once this illuminance data is collected, a pitch correction 
factor is calculated that is used to offset any exceedance of glare 
limits based on the roadway conditions.
Comments
    As noted in the section above on allowances for momentary glare 
exceedances, several commenters noted the potential effect of vehicle 
pitch on test results. For this reason, Ford recommended NHTSA adopt 
the IIHS pitch correction protocol. Ford commented that pitch 
correction is essential to produce results that are independent of 
differences in vehicle suspensions and are repeatable at different test 
tracks and different locations on the test tracks themselves. Ford 
noted that dynamic testing makes illuminance more difficult to measure 
because throughout the driving event, the vehicle pitch changes and 
effects from instrumentation inaccuracies increase proportionately. On 
the other hand, Intertek claimed that pitch correction would not be 
necessary unless there is a sustained change in pitch longer than 0.1 
seconds.
Agency Response
    After analyzing the comments and its own testing NHTSA has modified 
the proposal by adding in an explicit allowance for pitch variation: 
The agency will not consider any illuminance measurements recorded 
while the vehicle pitch exceeds the average pitch recorded throughout 
the entire measurement distance range specified for that scenario by 
more than 0.3 degrees.
    Although the NPRM did not propose any adjustments to directly take 
vehicle pitch into account, the NPRM requested comment on this issue. 
Further, the proposed test procedures controlled for the following 
factors that could affect pitch:
     Vehicle loading and suspension--the headlamps will be 
aimed when the vehicle is loaded as it will be during testing, and the 
gas tank (if the vehicle is equipped with one) is maintained at lease 
three-quarters full. The tires will be within 1 psi of recommended cold 
pressure.
     Road surface--the road surface must have an IRI 
measurement of less than 1.5 m/km.
     Vehicle acceleration--the vehicle speed must be maintained 
within 1 mph of the target test speed throughout the test run.
    In addition to these procedures, as explained above, the proposal 
also contained an allowance for momentary glare exceedances that was 
intended to account for variations in illumination due to uncontrolled 
testing variables, including minor imperfections in the road surface 
that can cause glare exceedances by affecting vehicle pitch.
    Despite these specifications, NHTSA's test data revealed two 
situations in which vehicle pitch still impacted measured illuminance 
and were not accounted for in the provisions listed above.
    First, NHTSA repeatedly observed small cyclical pitch changes 
related to road surface undulations, which affected illuminance 
measurements. For one example, see Figure 34.
[GRAPHIC] [TIFF OMITTED] TR22FE22.032

    Here, where the maximum pitch occurs (at about 85 m), there is a 
peak in the illuminance reading. The highest illuminance value (at 
about 31 m) also coincides with a positive spike in pitch. (In these 
instances, the pitch did not exceed the average pitch by more than 0.3 
degrees, so if this were a compliance test, these values would still be 
considered when assessing compliance; in any case, in this instance, 
all illuminance values are still within the glare limits).
    To better understand the sources of the pitch oscillations 
identified in testing, NHTSA collected pitch information both when the 
test vehicle was moving, and when it was stationary at the same (or as 
close as possible) location on the test surface. See Table 7. The pitch 
measurements were similar, indicating that dynamic contributors were 
generally small. Accordingly, although the testing did not show any 
instances where pavement-related vehicle pitching led to a glare 
exceedance that would be excused through the final pitch variation 
allowance, the agency recognizes the possibility for this to occur and 
has thus accounted for pitch in the regulatory text.

[[Page 9976]]

           Table 7--Vehicle Pitch in Static and Dynamic States
------------------------------------------------------------------------
                                                                 Pitch
                           Distance                              (deg.)
------------------------------------------------------------------------
Speed: 41 mph:
    148.982..................................................        0.3
    119.254..................................................       0.46
    59.605...................................................       0.51
    29.926...................................................       0.64
    15.145...................................................       0.65
Speed: 0 mph (static):
    149.058..................................................       0.17
    119.274..................................................       0.51
    59.650...................................................       0.46
    29.939...................................................       0.63
    15.152...................................................       0.63
------------------------------------------------------------------------

    Second, NHTSA observed pitch changes related to acceleration. For 
example, NHTSA tested the lower beams on the Fusion at 69 mph in a 
straight-path scenario. See Figure 35. When the vehicle reached the 
beginning of the illuminance measurement range (220 m) it had not yet 
attained the target speed, so it was still accelerating and pitching 
upward, resulting in an ``exceedance'' of the applicable glare limit. 
The pitch of 1.1 degrees during the exceedance was greater than 0.3 
degrees over the average pitch of 0.68 degrees. This shows that pitch 
in excess of the proposed allowance could lead to an exceedance of the 
glare limits.\166\
---------------------------------------------------------------------------

    \166\ Because the target speed had not yet been attained, had 
this been a compliance test, the measured illuminance value would 
not be having been considered in determining compliance. We also 
note that this glare exceedance lasted for more than 0.1 second, so 
it would not have been addressed with the momentary glare allowance.
[GRAPHIC] [TIFF OMITTED] TR22FE22.033

    Based on these instances of vehicle pitch fluctuations impacting 
measured illuminance (due to either the road surface or acceleration), 
the final rule includes an allowance for vehicle pitch variation. 
NHTSA's testing demonstrated that it is generally possible to maintain 
pitch within less than 0.3 degrees of the average pitch recorded 
throughout the entire measurement distance. We believe that no 
allowance for pitch, or a higher pitch variation allowance (e.g., ``by 
no more than 0.4 degrees)--resulting in a more stringent test--could 
lead manufacturers to design headlamps providing sub-optimal visibility 
(because manufacturers might aim the headlamps down to minimize the 
possible effects of pitch during a compliance test).
    We believe this adjustment methodology is preferable to the IIHS 
pitch correction procedure for the purposes of this rule. The IIHS test 
procedure relies on interpolation, which introduces inaccuracy (without 
knowing the linearity of the beam pattern). The final rule methodology 
does not interpolate but instead measures pitch directly. By 
controlling pitch to 0.3 degrees or less and regulating performance 
only within that range, we are directly measuring the aspect of 
performance that matters to safety. The IIHS procedure also requires 
that the vehicle path be mapped with respect to pitch prior to running 
the test. The final rule procedure does not require this, which 
simplifies the test procedure.
11. Repeatability
    The NPRM included an analysis of the repeatability of the test data 
from the 2015 ADB Test report.\167\ That test data was based on the 
proposed test procedures, which utilized dynamic stimulus vehicles.
---------------------------------------------------------------------------

    \167\ NPRM, pp. 51789-51798.
---------------------------------------------------------------------------

Comments
    NHTSA received a variety of comments on the repeatability of the 
proposed test. One commenter, Intertek, agreed with NHTSA's 
repeatability analysis. Other commenters expressed concerns that the 
proposed test procedures were not repeatable based upon the complexity 
of the proposed test procedures and a variety of test conditions that 
might affect repeatability. Commenters identified several factors they 
argued would adversely affect repeatability.\168\
---------------------------------------------------------------------------

    \168\ A number of comments about repeatability were related to 
the proposal to use stimulus vehicles. Because the final rule does 
not use stimulus vehicles, we need not address those comments as the 
issue is moot.
---------------------------------------------------------------------------

    Auto Innovators, MEMA, the Alliance, TSEI, and Volkswagen commented 
that the proposed track testing was overly complicated and expressed 
concerns that it would not lead to repeatable results.
    SAE commented generally that test results (both for tests conducted 
on the same track and for tests conducted on different tracks) would be 
sensitive to the environment because lighting measurements are affected 
by small changes in conditions. Other commenters echoed this and 
identified unspecified test conditions that they argued could introduce 
uncontrolled variability, causing acceptable levels of repeatability 
and reproducibility of the test scenarios to be extremely challenging 
to achieve, particularly given the stringency of the requirements. The 
Alliance and Volkswagen commented that, although the NPRM requires the 
photometers to be zero-calibrated to the ambient light, the ambient 
light can change throughout the data collection, introducing 
uncontrollable variability. Volkswagen

[[Page 9977]]

also stated that the presence of reflectors in the environment may also 
cause variances by redirecting part of the test vehicle lights into the 
photometers. Volkswagen also commented that the NPRM only specified 
that there be no precipitation and a dry road surface, but other 
environmental conditions such as fog, dust, or pollution could affect 
results. TSEI identified variation in road materials and reflectivity, 
weather conditions, and road surface as other factors. Toyota 
identified the test vehicle's suspension, tires, and acceleration/
deceleration during the test as affecting repeatability; it stated that 
it is unclear whether any test track meets the ideal conditions 
specified in the proposal, and, if so, whether such a test track can be 
reasonably accessible to conduct compliance testing.
    Auto Innovators commented that to evaluate testing variability, one 
member company repeated a test series using a vehicle tested by FTTA 
and cited in the NPRM. The full test series was repeated under the same 
conditions using comparable measurement equipment. The commenter stated 
that, despite careful attention to test setup and test conditions, the 
results varied from those obtained by FTTA to the extent that the 
variation altered the compliance status of the vehicle.
Agency Response
    The final rule substantially reduces the complexity of the test, 
especially by using test fixtures instead of stimulus vehicles and 
streamlining the test scenarios. Further, while it is true that 
lighting measurements can be sensitive to small changes in conditions, 
NHTSA's testing has shown that measurement of headlamp illuminance 
using the whole vehicle, rather than a component-level test, can be 
accomplished in a repeatable manner.\169\ NHTSA has identified, and the 
test parameters and conditions specified in the final rule control for, 
the major sources of test-related variability, including vehicle pitch. 
This final rule also includes a data filter, which will smooth out the 
measured illuminance data, in addition to the proposed allowance for 
momentary glare exceedances, which should address any otherwise 
uncontrolled ambient illumination, among other things.
---------------------------------------------------------------------------

    \169\ 2105 ADB Test Report, p. 172.
---------------------------------------------------------------------------

    NHTSA conducted a series of tests to determine the level of 
variability in the track test finalized today, as well as the SAE J3069 
test method.\170\ To do this, NHTSA analyzed data from testing using 
the original-equipment lower beams on a FMVSS-certified 2016 Volvo 
XC90. Multiple runs of each test scenario were conducted to permit 
different types of repeatability analyses, including: Same night 
(gauge); different night (test procedure); and different headlamp 
aiming technician (reproducibility). Data from these test trials were 
analyzed for each measurement distance sub-range (interval), 
calculating the mean, standard deviation, 95% confidence interval, and 
95% prediction interval.\171\ Sample results of Test Number 1 
(straight--oncoming) for the sub-range of 120 m to 220 m are shown 
below in Tables 8 through 10. (Throughout this section, ``Test Number'' 
refers to the scenario test numbers as reported in the repeatability 
report. Please see Table 1 (NHTSA Test Matrix) in that report. The test 
scenarios in the repeatability report are the same as the test 
scenarios specified in Table XXII of this final rule, but the numbering 
of the test scenarios differs.) Data similar to this (i.e., 10 test 
repetitions, 10 separate test days, and 3 headlamp aiming technicians) 
were collected for every final rule scenario. Testing with the lower 
beam headlamps activated (the test vehicle was not ADB-equipped) 
allowed the agency to isolate variability to factors related to the 
test and to be certain that ADB performance itself did not contribute 
to variability. Oncoming and same direction data were collected during 
the same run, using receptor heads (i.e., light sensors) placed in the 
appropriate positions.
---------------------------------------------------------------------------

    \170\ See Mazzae, E.N., Baldwin, G.H.S., Satterfield, K., & 
Browning, D.A. 2021. Adaptive Driving Beam Headlamps Test 
Repeatability Assessment. Washington, DC: National Highway Traffic 
Safety Administration. The discussion here is a summary of that 
report, which has been placed in the docket for this rulemaking.
    \171\ NHTSA has used similar analyses before to assess the 
reliability and repeatability of test methods developed for FMVSS. 
As an example, refer to the test report ``Repeatability, 
Reproducibility, and Sameness of Quiet Vehicle Test Data'' 
supporting the development of FMVSS No. 141, Minimum sound level for 
hybrid and electric vehicles. See Docket number NHTSA-2016-0125-0006 
at www.regulations.gov.

                Table 8--NHTSA Test No. 1, 220 m-120 m, Gauge (Measurement System) Repeatability
----------------------------------------------------------------------------------------------------------------
                                                                                                   Difference
                                                                                                 between pitch
                                                                                                 maximum (sub-
                                 Repetition    Car  eye point    Cycle  eye      Truck  eye     range) and pitch
    Descriptive statistic        (all in one        (lux)       point  (lux)    point  (lux)    average (entire
                                   night)                                                         measurement
                                                                                                   distance)
                                                                                                   (degrees)
----------------------------------------------------------------------------------------------------------------
                                            1          0.0688          0.0751          0.0652             0.0900
                                            2          0.0666          0.0802          0.0602             0.1600
                                            3          0.0751          0.0724          0.0618             0.1400
                                            4          0.0665          0.0764          0.0560             0.1000
                                            5          0.0686          0.0675          0.0561             0.1100
                                            6          0.0711          0.0722          0.0599             0.1000
                                            7          0.0709          0.0730          0.0542             0.1100
                                            8          0.0830          0.0763          0.0590             0.1000
                                            9          0.0693          0.0822          0.0574             0.0900
                                           10          0.0736          0.0822          0.0625             0.1400
Mean.........................  ..............          0.0714          0.0758          0.0592  .................
StdDev (S)...................  ..............          0.0049          0.0048          0.0034  .................
Min..........................  ..............          0.0665          0.0675          0.0542  .................
Max..........................  ..............          0.0830          0.0822          0.0652  .................
95% C.I. Margin of Error (+/-  ..............          0.0035          0.0034          0.0024  .................
 )...........................
95% C.I. Upper Limit.........  ..............          0.0749          0.0791          0.0617  .................
95% C.I. Lower Limit.........  ..............          0.0678          0.0724          0.0568  .................
95% Prediction Interval        ..............          0.0117          0.0113          0.0080  .................
 Margin of Error (+/-).......

[[Page 9978]]

 
95% P.I. Upper Limit.........  ..............          0.0831          0.0870          0.0673  .................
95% P.I. Lower Limit.........  ..............          0.0596          0.0645          0.0512
----------------------------------------------------------------------------------------------------------------

                      Table 9--NHTSA Test No. 1, 220 m-120 m, Test Procedure Repeatability
----------------------------------------------------------------------------------------------------------------
                                                                                                   Difference
                                                                                                 between pitch
                                 Repetition                                                      maximum (sub-
    Descriptive statistic         (one per     Car  eye point    Cycle  eye      Truck  eye     range) and pitch
                                   night)           (lux)       point  (lux)    point  (lux)    average (entire
                                                                                                  test  number
                                                                                               range)  (degrees)
----------------------------------------------------------------------------------------------------------------
                                            1          0.0839          0.0905          0.0774             0.1048
                                            2          0.0847          0.0805          0.0564             0.1072
                                            3          0.0796          0.0857          0.0662             0.1030
                                            4          0.0713          0.0772          0.0522             0.1313
                                            5          0.0745          0.0865          0.0634             0.1061
                                            6          0.0777          0.0865          0.0614             0.1260
                                            7          0.0717          0.0745          0.0554             0.1226
                                            8          0.0794          0.0718          0.0559             0.1271
                                            9          0.0817          0.0884          0.0679             0.1210
                                           10          0.0815          0.0686          0.0581             0.0990
Mean.........................  ..............          0.0786          0.0810          0.0614  .................
StdDev (S)...................  ..............          0.0048          0.0076          0.0076  .................
Min..........................  ..............          0.0713          0.0686          0.0522  .................
Max..........................  ..............          0.0847          0.0905          0.0774  .................
95% C.I. Margin of Error (+/-  ..............          0.0034          0.0055          0.0054  .................
 )...........................
95% C.I. Upper Limit.........  ..............          0.0820          0.0865          0.0668  .................
95% C.I. Lower Limit.........  ..............          0.0752          0.0755          0.0560  .................
95% Prediction Interval        ..............          0.0113          0.0181          0.0179  .................
 Margin of Error (+/-).......
95% P.I. Upper Limit.........  ..............          0.0899          0.0991          0.0794  .................
95% P.I. Lower Limit.........  ..............          0.0673          0.0629          0.0435
----------------------------------------------------------------------------------------------------------------

                                                Table 10--NHTSA Test No. 1, 220 m-120 m, Reproducibility
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                                           Difference
                                                                                                                                         between pitch
                                                                                                                                         maximum (sub-
            Descriptive statistic                      Aimer             Repetition     Car eye point     Cycle eye       Truck eye     range) and pitch
                                                                                            (lux)        point (lux)     point (lux)    average (entire
                                                                                                                                          test  number
                                                                                                                                       range)  (degrees)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                              A                                     1          0.0545          0.0599          0.0578             0.1323
                                              B                                     1          0.0673          0.0672          0.0581             0.1522
                                              B                                     2          0.0658          0.0662          0.0556             0.0977
                                              C                                     1          0.0632          0.0631          0.0545             0.0983
                                              C                                     2          0.0676          0.0663          0.0540             0.1549
Mean........................................  .......................  ..............          0.0637          0.0645          0.0560  .................
StdDev (S)..................................  .......................  ..............          0.0054          0.0030          0.0019  .................
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The standard deviation is a measurement of the variation within the 
data set. The 95th percentile confidence interval is the estimate of 
the upper and lower illuminance values in which there is a 95% 
probability that the true mean falls within this interval. The 
confidence interval is calculated using the equation
[GRAPHIC] [TIFF OMITTED] TR22FE22.034

[[Page 9979]]

    Where the margin of error is calculated using t as the upper 
critical value for the t distribution with n-1 degrees of freedom, S as 
the standard deviation, n as sample size. The confidence interval is 
then calculated by summing the mean (x) and the margin of error. The 
95th percentile prediction interval is the estimate of the interval of 
which there is a 95% probability that future measurements will be 
within. The prediction interval is calculated using the equation:
[GRAPHIC] [TIFF OMITTED] TR22FE22.035

    Where the margin of error is calculated using t as the upper 
critical value for the t distribution with n-1 degrees of freedom, S as 
the standard deviation, and n as the sample size. The prediction 
interval is then calculated by summing the mean (x) and the margin of 
error.
    Note that CI95 and PI95 are 
dependent on the number of values collected (t0.975 is large 
for small sample sizes and decreases as more data are collected). That 
is to say, the more data collected for a distribution, the more 
confident we can be of where the true mean is located and where future 
measurement values will fall. While a standard deviation can be 
calculated for a very small sample size, CI and PI will be large for 
small samples, even if the population standard deviation is small. 
Taken together, the standard deviation and the prediction interval can 
be used to quantify the repeatability of the test procedure. The 
smaller the standard deviations and the tighter the prediction 
interval, the smaller the range of values we will expect future values 
to be within, indicating a tighter precision of measurement system.
    The magnitude of the prediction intervals can be used to determine 
how a vehicle with a similar headlighting system and beam pattern is 
likely to perform with respect to the glare limits. The prediction 
interval indicates the range within which a similar vehicle's measured 
illuminance value is 95% likely to fall (5% chance of not falling 
within the range). If the upper end value of the prediction interval is 
less than the glare limit for a measurement distance sub-range, then a 
similar vehicle's measured value is at least 95% likely to be less than 
the glare limit when tested by NHTSA.\172\ Because the repeatability of 
the measurement system and test procedure produced small standard 
deviations, the variability of the illuminance values should not differ 
substantially, even if the maximum illuminance value for other 
headlighting systems is higher. This assumption holds true provided the 
headlamp beam pattern under test demonstrates similar gradients in and 
around the measurement locations.
---------------------------------------------------------------------------

    \172\ For example, if this analysis produces a 95% prediction 
interval of 0.180 lux and the limit is 1.8, a system with a true 
performance of 1.62 or less will have a 95% or greater probability 
of receiving a passing score if the agency were to do a compliance 
test, using a single run.
---------------------------------------------------------------------------

    Table 11 below pools the standard deviation for the oncoming 
straight and left curve scenarios (Test Number 1,3,4,7--each of these 
tests provide similar means), and the same direction straight and left 
curve scenarios (Test Number 2,5), and lists the standard deviation 
observed for the oncoming right medium curve (Test Number 6) and 
oncoming-right large curve (Test Number 8) for each measurement 
distance sub-range.

                              Table 11--Test Procedure: Standard Deviation Results
----------------------------------------------------------------------------------------------------------------
                                                           Same direction
                                        Oncoming NHTSA       NHTSA test       Oncoming right     Oncoming right
                NHTSA                  test numbers  1,     numbers 2, 5        NHTSA test         NHTSA test
                                        3, 4, 7  (lux)         (lux)         number 6  (lux)    number 8  (lux)
----------------------------------------------------------------------------------------------------------------
Measurement Distance Sub-Range:                        All standard deviations were at or below:
                                     ---------------------------------------------------------------------------
    220 m-120 m.....................             0.0076  .................  .................  .................
    150 m-120 m.....................             0.0068  .................  .................  .................
    119.9 m-60 m....................             0.0156  .................  .................  .................
    100 m-60 m......................  .................             0.0153  .................  .................
    70 m-60 m.......................  .................  .................  .................             0.5996
    59.9 m-30 m.....................             0.0599             0.0494  .................             0.5921
    50 m-30 m.......................  .................  .................             0.9648  .................
    29.9 m-15 m.....................             0.0713             0.1324             0.0651             0.0602
----------------------------------------------------------------------------------------------------------------

                                                           Table 12--Prediction Interval Margin of Error Values of the Test Procedure
                                                                                          [NHTSA Test]
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                 Glare
Measurement distance sub-range   limit    Test number 1      Test number 2      Test number 3      Test number 4      Test number 5      Test number  6      Test number 7      Test number  8
                                 (lux)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
                                                     95th Percentile Prediction Interval Car Eye Point/Passenger Side Mirror (Values in lux)
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
220 m-120 m...................     0.3  0.0113 (3.8%)....  .................  .................  .................  .................  ..................  0.0128 (4.3%)....  ..................
150 m-120 m...................     0.3  .................  .................  .................  0.0145 (4.8%)....  .................  ..................  .................  ..................
119.9 m-60 m..................     0.6  0.0357 (6.0%)....  .................  .................  0.0238 (4.0%)....  .................  ..................  0.0171 (2.9%)....  ..................
70 m-60 m.....................     0.6  .................  .................  .................  .................  .................  ..................  .................  1.4225 (237%) *
50 m-30 m.....................     1.8  .................  .................  .................  .................  .................  2.2890 (127%) *...  .................  ..................
59.9 m -30 m..................     1.8  0.0741 (4.1%)....  .................  0.0690 (3.8%)....  0.0933 (5.2%)....  .................  ..................  0.0812 (4.5%)....  1.4047 (78%) *
29.9 m-15 m...................     3.1  0.1436 (4.6%)....  .................  0.1672 (5.4%)....  0.1693 (5.5%)....  .................  0.1534 (4.9%).....  0.1637 (5.3%)....  0.1427 (4.6%)
100 m-60 m....................     4.0  .................  0.0331 (0.8%)....  .................  .................  0.0189 (0.5%)....  ..................  .................  ..................

[[Page 9980]]

 
59.9 m-30 m...................    18.9  .................  0.0963 (0.5%)....  .................  .................  0.1121 (0.6%)....  ..................  .................  ..................
29.9 m-15 m...................    18.9  .................  0.2348 (1.2%)....  .................  .................  0.3141 (1.7%)....  ..................  .................  ..................
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    The prediction intervals shown in Table 12 are small compared to 
the limits that are finalized for each measurement distance sub-range. 
For instance, we found that within the sub-range of 120 m to 220 m Test 
Number 1 resulted in a prediction interval of 0.0113 lux as compared to 
the limit of 0.3 lux. This interval represents 3.8% of the limit.
    Both measurement system (gauge) repeatability results and full test 
repeatability results revealed NHTSA test scenarios involving right 
curves (Test Numbers 6 and 8) to be less repeatable than the other test 
scenarios (marked with * in the table). Unsurprisingly, these two 
scenarios showed a pattern of higher standard deviations with respect 
to the other NHTSA test scenarios. SAE Test Drive 3, in which the test 
fixture was located to the right of the test vehicle also showed a 
pattern of higher standard deviations as compared to the other 
scenarios. As is the case with many U.S. vehicle lower beam headlamps, 
the 2016 Volvo XC90 lamps produced beam patterns with a higher right-
side horizontal cutoff. The variability of measurements recorded on the 
right side of the vehicle (right curve scenarios) is attributable to 
the cutoff at the right portion of the headlamp pattern of this vehicle 
projecting near the location of the lower-mounted light sensors. The 
lower beam headlamps tested in this repeatability study exceeded the 
glare limits for these two-measurement distance sub-ranges as well. An 
ADB pattern designed to meet the requirements finalized today will need 
to provide a greater angular distance between the cutoff and the light 
sensors to meet the minimum glare requirements as described earlier in 
the right curve discussion. With such a design, the agency anticipates 
that similar repeatability will be obtained for right curves as was 
demonstrated for the other scenarios.
    Breaking down the 8 NHTSA test scenarios by measurement distance 
sub-range and measurement points (light sensor locations) gives a total 
of 99 data points. The finalized test method found the same pass/fail 
results for 97 of the 99 data points in every one of the 10 test 
procedure repetitions. For the vehicle's lower beam headlamps under 
test, 94 of those data points, without fail, were under the glare limit 
criteria and 3 of the data points consistently exceeded the glare 
limits. The vehicle consistently failed to meet the glare criteria for 
Test Number 6 (medium right curve) at the car eye point for the sub-
range 50 m-30 m. It also consistently failed to meet the glare 
criterion for Test Number 8 (Large Right Curve) at the Car Eye and 
Cycle Eye point for the sub-range 70 m-60 m. The 2 data points with 
inconsistent results (sometimes the test reported that the vehicle met 
the criteria and other times it reported a failure) were also found on 
these two right curve tests. Test Number 6 had mixed results at the 
cycle eye point for the sub-range 50 m-30 m and Test Number 8 had mixed 
results at the car eye point for the sub-range 59.9 m-30 m. As 
discussed above, we do not expect any mixed results for an ADB beam 
pattern designed to meet the track test finalized today.
    NHTSA also conducted testing to examine the possibility of 
variability introduced by different technicians visually aiming the 
headlamps. This reproducibility analysis examined the effects of three 
different technicians performing headlamp aiming prior to running a 
test set. This analysis found only small differences in illuminance 
measurements between datasets associated with different headlamp aiming 
operators. The pooled standard deviations for each orientation are 
shown in Table 13 below.

          Table 13--Reproducibility: Standard Deviation Results
------------------------------------------------------------------------
                                      Oncoming NHTSA     Same direction
                                     test numbers 1,       NHTSA test
                                      3, 4, 6, 7, 8       numbers 2, 5
                                          (lux)              (lux)
------------------------------------------------------------------------
Measurement Distance Sub-Range:      All standard deviations were below:
                                   -------------------------------------
    220 m-120 m...................             0.0055  .................
    150 m-120 m...................             0.0069  .................
    119.9 m-60 m..................             0.0123  .................
    100 m-60 m....................                N/A             0.0153
    70 m-60 m.....................             0.0122  .................
    59.9 m-30 m...................             0.0366             0.0521
    50 m-30 m.....................             0.0355  .................
    29.9 m-15 m...................             0.0933             0.1264
------------------------------------------------------------------------

    NHTSA also assessed the repeatability of the SAE J3069 test (Table 
14). We found that the SAE test resulted in similar variability of both 
measured illuminance and test outcomes.

[[Page 9981]]

                              Table 14--Test Procedure: Standard Deviation Results
----------------------------------------------------------------------------------------------------------------
                                                           Same direction
                                        Oncoming NHTSA       NHTSA test       Oncoming right     Oncoming right
                NHTSA                  test numbers  1,     numbers 2, 5        NHTSA test         NHTSA test
                                        3, 4, 7  (lux)         (lux)         number 6  (lux)    number 8  (lux)
----------------------------------------------------------------------------------------------------------------
Measurement Distance Sub-Range:                        All standard deviations were at or below:
                                     ---------------------------------------------------------------------------
    220 m-120 m.....................             0.0076  .................  .................  .................
    150 m-120 m.....................             0.0068  .................  .................  .................
    119.9 m-60 m....................             0.0156  .................  .................  .................
    100 m-60 m......................  .................             0.0153  .................  .................
    70 m-60 m.......................  .................  .................  .................             0.5996
    59.9 m-30 m.....................             0.0599             0.0494  .................             0.5921
    50 m-30 m.......................  .................  .................             0.9648  .................
    29.9 m-15 m.....................             0.0713             0.1324             0.0651             0.0602
----------------------------------------------------------------------------------------------------------------

 
                                      Oncoming SAE test    Preceding SAE                         Preceding SAE
                 SAE                     drives 1, 2      test drives  10,  Oncoming SAE test    test drive 12
                                            (lux)          11, 12  (lux)      drive 3  (lux)         (lux)
----------------------------------------------------------------------------------------------------------------
Measurement Distance:                                  All standard deviations were at or below:
                                     ---------------------------------------------------------------------------
    155.............................             0.0141             0.0228             0.1234             0.1436
    120.............................             0.0132             0.0231             0.1489             0.1909
    60..............................             0.0219             0.0226             0.2464             0.3020
    30..............................             0.0380             0.0341             0.0413             0.3503
----------------------------------------------------------------------------------------------------------------

D. Laboratory (Component-Level) Testing

1. Need for Laboratory Testing
    The NPRM proposed that an ADB system would also be subject to the 
existing component-level laboratory-based upper and lower beam 
photometry requirements. With respect to the adaptive beam, the NPRM 
proposed that an area of reduced intensity meet the applicable Table 
XIX lower beam photometry requirements (maxima and minima), and that an 
area of unreduced intensity meet the applicable Table XVIII upper beam 
photometry requirements. The NPRM proposed that when the ADB system is 
producing a lower beam, that beam be subject to all the Table XIX lower 
beam requirements, and when producing an upper beam, the beam be 
subject to all the Table XVIII upper beam photometric requirements. The 
NPRM proposed to require that the system provide only a lower beam when 
the vehicle is travelling less than 25 mph (unless overridden by the 
driver).\173\
---------------------------------------------------------------------------

    \173\ For a general explanation of the laboratory photometry 
requirements, see the NPRM at p. 51770.
---------------------------------------------------------------------------

    This differed from SAE J3069 in some respects. SAE J3069 only 
specifies that the lower beam maxima are not exceeded within the area 
of reduced intensity, and that the lower beam minima be met in the area 
of unreduced intensity. (These provisions reference the relevant SAE 
photometric standards; the proposal instead appropriately referenced 
the upper and lower beam photometric requirements in Tables XVIII and 
XIX of the standard.)
Comments
    Some commenters supported the inclusion of at least some laboratory 
testing requirements. AAA and Intertek supported applying the existing 
upper beam photometric requirements to the upper beam, Consumer Reports 
supported requiring that the part of the adaptive beam that is cast 
near other vehicles not exceed the current lower beam maxima, and the 
part of the adaptive beam that is cast onto unoccupied roadway not 
exceed the current upper beam maxima. Consumer Reports also supported 
applying the lower beam minima to areas of reduced intensity and the 
upper beam minima to areas of unreduced intensity. Zoox supported 
applying the existing laboratory requirements to the upper and lower 
beams.
    In contrast, both SAE and Global disagreed that photometric 
component testing is necessary in addition to vehicle testing. SAE 
explained that, when SAE J3069 was published, component level testing 
was included as an additional metric to aid in lamp manufacturers' 
process controls and also because it is a familiar compliance method. 
The SAE J3069 rationale accordingly explained that, if vehicle-level 
testing of ADB systems were to be included in FMVSS No. 108, ``any need 
for laboratory photometric requirements may be reconsidered for 
removal.'' SAE therefore requested that the final rule not include 
component testing.
Agency Response
    The final rule retains the laboratory testing requirements because 
the full-vehicle track test alone may not be sufficient to ensure that 
an ADB system provides adequate visibility and does not glare other 
vehicles, as discussed further below. Accordingly, the final rule 
applies the existing laboratory testing requirements to any beam an ADB 
system may provide (a lower beam, an upper beam, or an adaptive driving 
beam). (The different types of beams classified in the final rule are 
discussed in Section VIII.D.2.)
    The full vehicle track test and the laboratory-based component test 
are complementary. The full vehicle dynamic track test only evaluates 
glare; it does not evaluate visibility. The final requirements include 
laboratory testing requirements that ensure that the ADB system always 
provides the driver with a minimum level of visibility.
    The laboratory testing requirements generally assure adequate 
visibility by specifying minimum levels of light at certain locations 
(test points) that roughly correspond to different locations on the 
road. As explained in Section VIII.D.2, we have modified the proposal 
to give manufacturers greater flexibility in determining which areas of 
the roadway receive an area of reduced intensity or an area of 
unreduced intensity. For the former, the appropriate minimum visibility 
is the applicable lower beam minima; for the

[[Page 9982]]

latter, the appropriate minimum visibility is the applicable upper beam 
minima. Similarly, the lower beam minima indicate the appropriate 
minimum visibility for the lower beam, and the upper beam minima for 
the upper beam.
    Laboratory testing will complement the track test to minimize glare 
to other vehicles. The laboratory testing requirements minimize glare 
by specifying photometric maxima at certain test points. The track test 
evaluates whether an ADB system glares a test fixture in specific 
scenarios. While the final track test requirements encompass many 
common scenarios (e.g., a single oncoming vehicle in the adjacent 
lane), they do not test every conceivable scenario. Laboratory testing 
will therefore help serve as a backstop to the track test. Moreover, 
the track test evaluates glare out to 220 meters. Extremely bright 
upper beams (for example, an ECE-approved upper beam that exceeds the 
current FMVSS No. 108 75,000 cd upper beam maximum) could create glare 
further than this distance. The laboratory testing requirements will 
therefore also ensure that upper beams are not exceedingly bright. 
(Indeed, if the current upper beam maxima did not apply to the upper 
beam of an ADB system, upper beam maximum intensity would effectively 
be unregulated). Accordingly, the final rule specifies that the lower 
beam and an area of reduced intensity must not exceed any applicable 
Table XIX (lower beam) maxima, and the upper beam and areas of 
unreduced intensity must not exceed any applicable Table XVIII (upper 
beam) maxima.
2. Definitions of Areas of Reduced and Unreduced Intensity
    The NPRM proposed (in S9.4.1.6.6-.7) that ``when the system is 
producing a lower beam with an area of reduced light intensity designed 
to be directed towards oncoming or preceding vehicles, and an area of 
unreduced intensity in other directions,'' the system must meet the 
Table XIX (lower beam) photometric requirements within the area of 
reduced intensity and the Table XVIII (upper beam) photometric 
requirements in the within the area of unreduced intensity. The 
proposed rule did not otherwise define the areas of reduced and 
unreduced intensity.
Comments
    Several commenters suggested clarifications to the definitions or 
references to the areas of reduced and unreduced intensity. ALNA, Zoox, 
and Valeo commented that the definitions of the area of reduced 
intensity and/or area or unreduced intensity were unclear. Mercedes 
suggested expanding the definition of the area of reduced intensity to 
include portions of the roadway other than those occupied by other 
vehicles because sophisticated ADB systems are capable of dimming areas 
of the beam pattern directed towards retroreflective signs or wet road 
surfaces in order to minimize glare to the driver. Stanley requested 
confirmation that the area of reduced intensity corresponds to the 
windshield area of an oncoming vehicle and the area of unreduced 
intensity refers to the area outside of the area of reduced intensity. 
Ford suggested edits to clarify the regulatory text setting out the 
dimmed and undimmed area requirements. It suggested that instead of 
referring to the lower beam, the regulatory text refer to the 
``adaptive driving beam,'' and suggested rearranging the regulatory 
text. Valeo similarly commented that classifying the adaptive beam as a 
lower beam is misleading because it is actually a modified driving or 
upper beam and suggested including a definition of ``adaptive driving 
beam.'' Intertek suggested requiring that the system emit a base lower 
beam, which is only augmented by adding light to the portions of the 
beam in which a preceding or oncoming vehicle is not detected, to the 
limit that when there are no preceding or coming vehicles detected the 
emitted beam is a compliant upper beam. This would, it contended, 
ensure that the augmented lower beam is always compliant to the 
applicable lower beam photometry requirements. Zoox commented that the 
NPRM appeared to assume that the adaptive beam is a defined, static 
beam pattern that is generated based on camera recognition of oncoming 
or preceding traffic. It stated that the laboratory test requirements 
should be technology neutral with respect to the manner and method of 
controlling and producing an adaptive beam.
    Some commenters requested that the agency establish more specific 
laboratory test requirements. Zoox commented that the proposed 
laboratory test requirements were not clear on how to determine which 
portion of an adaptive beam is to be checked against the lower beam or 
upper beam minima and maxima. For example, a system may progressively 
dim an LED array across the headlamp width as vehicle distance closes 
for oncoming traffic. The ADB pattern may also differ for oncoming 
versus preceding traffic. Zoox requested clarification of which test 
points would apply and how they would be evaluated. SL and Intertek 
commented that specific test requirements need to be established 
because it would be impracticable to test the hundreds of possible 
adaptive beam patterns.
Agency Response
    The final rule does not adopt the proposed regulatory text that 
referred to an area of reduced intensity as being ``designed to be 
directed towards oncoming or preceding vehicles,'' and to the area of 
unreduced intensity as being directed ``in other directions.'' The 
proposed text implied that an area of reduced intensity must be 
directed towards oncoming or preceding vehicles and that an area of 
unreduced intensity must be directed towards unoccupied portions of the 
roadway. The final rule defines a new beam type, an ``adaptive driving 
beam,'' and adopts the definition of this in SAE J3069 MAR2021 as ``a 
long-range light beam for forward visibility, which automatically 
modifies portions of the projected light to reduce glare to traffic 
participants on an ongoing, dynamic basis.'' It requires that areas of 
reduced intensity conform to the Table XIX test points, areas of 
unreduced intensity conform to the Table XVIII test points and allows 
for a 1-degree transition zone between areas of reduced and unreduced 
intensity.
    The final rule is intended to give manufacturers the flexibility to 
design systems that provide an area of reduced intensity not only to 
prevent glare to oncoming or preceding vehicles, but also in other 
situations in which a dimmed beam would be beneficial (such as towards 
retroreflective signs). Creating a new ``adaptive driving beam'' 
classification, distinct from the existing lower and upper beam 
definitions, accomplished this.\174\ The intent behind these changes is 
to essentially, as Intertek suggested, provide that the system emit a 
lower beam, which is only augmented by adding light to the portions of 
the beam in which a preceding or oncoming vehicle is not detected, to 
the limit that when there are no preceding or coming vehicles \175\ the 
emitted beam is an upper beam.
---------------------------------------------------------------------------

    \174\ This is also related to comments that recommended not 
specifying the upper beam minima in the area of unreduced intensity. 
The final rule retains the specification of the upper beam minima in 
the area of unreduced intensity, but now gives manufacturers the 
flexibility to use an area of reduced intensity on roadway not 
occupied by oncoming or preceding vehicles. This is discussed in 
more detail in Section VIII.D.4.
    \175\ Or other situations, such as the presence of 
retroreflective signs, in which it would be appropriate or optimal 
to provide less than a full upper beam.

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

[[Page 9983]]

    Manufacturers will therefore have the flexibility to design the 
system to produce areas of reduced intensity and areas of unreduced 
intensity as they see fit, subject to several requirements or 
constraints:
     The adaptive driving beams must consist only of area(s) of 
reduced intensity, area(s) of unreduced intensity, and transition 
zone(s).
     When the ADB system is operating in manual mode, the 
system must provide only an upper beam or a lower beam. This was 
implicit in the proposed regulatory text but is made explicit in the 
final rule.
     When the ADB system is operating in automatic mode, the 
system must provide an adaptive driving beam. The adaptive driving beam 
is subject to several requirements, including the following:
    [ssquf] The adaptive driving beam must be designed to conform to 
the track test requirements.
    [ssquf] For speeds below 20 mph, the system must provide only lower 
beams (unless manually overridden).
    [ssquf] In an area of reduced intensity, the adaptive driving beam 
must be designed to conform to the Table XIX (lower beam) photometry 
requirements.
    [ssquf] In an area of unreduced intensity, the adaptive driving 
beam must be designed to conform to the Table XVIII (upper beam) 
photometry requirements.
    [ssquf] A 1-degree transition zone is permitted between any areas 
of reduced and unreduced intensity.
    These requirements are discussed in more detail in the following 
sections (except for the track test requirements, which were discussed 
in Section VIII.C).
    In conducting its compliance testing, NHTSA will request 
information from the manufacturer on how to power and control the 
headlamp.\176\ The lower and upper beams will be aimed prior to 
testing, and the aim will remain unchanged during testing. Testing of 
the lower and upper beams will be the same as it is currently. To test 
the adaptive driving beam, NHTSA will activate the headlamp in the 
goniometer according to the manufacturer's instructions to produce an 
adaptive driving beam pattern that is consistent with an ADB pattern 
that would appear in the real world with areas of reduced intensity, 
unreduced intensity, and/or transition zone(s). The ADB pattern 
generated will result in light directed toward all the test points in 
Tables XVIII and XIX. The issue then becomes which fixed test point 
falls within an area of reduced intensity, an area of unreduced 
intensity, or a transition zone. NHTSA will have manufacturers identify 
the portion(s) of the adaptive beam which are areas of reduced 
intensity and which are areas of unreduced intensity. The areas of 
reduced intensity must conform to the requirements for the test points 
in Table XIX, and the area of unreduced intensity must conform to the 
requirements for the test points in Table XVIII. Procedures for 
determining the transition for lower beams (similar to how the cutoff 
is determined, i.e., a scan) can be used to determine whether the 
transition zone exceeds 1 degree. Appendix B provides an example of how 
this would work in practice.
---------------------------------------------------------------------------

    \176\ This will include, as requested by Auto Innovators, 
calibration of any sensors required for ADB system performance in 
the laboratory prior to testing.
---------------------------------------------------------------------------

    Although NHTSA will rely on manufacturers to inform it on how to 
produce the beam--to some extent determining the precise contours of 
the beam--this will still adequately ensure both visibility and glare 
prevention. The adaptive driving beam may only consist of areas of 
reduced intensity conforming to Table XIX, areas of unreduced intensity 
conforming to Table XVIII, and/or transition zones between such areas. 
With respect to visibility, the beam must meet either the lower beam 
minima or the upper beam minima (other than in a transition zone). The 
driver will at a minimum always have the visibility provided by a 
traditional lower beam regardless of the size of the dimmed portion, up 
to and including a situation where the entire beam is an area of 
reduced intensity (i.e., a lower beam).
    This approach should also help ensure adequate glare minimization. 
First and most important, the system must be designed to conform to the 
track test requirements, which evaluate the adaptive driving beam in 
specific scenarios. Second, the laboratory testing requirements will 
ensure that any areas of reduced intensity (up to and including a 
pattern equivalent to a full lower beam) do not exceed the Table XIX 
(lower beam) maxima, and any areas of unreduced intensity (up to and 
including a pattern equivalent to a full upper beam), do not exceed the 
Table XVIII (upper beam) maxima.\177\
---------------------------------------------------------------------------

    \177\ We would expect manufacturers to design systems that avoid 
glare even in scenarios not included in the track test. A system 
that did not appropriately shade other vehicles, if not a non-
compliance, could potentially be a safety-related defect.
---------------------------------------------------------------------------

    These modifications should address the concerns raised by 
commenters about which Table XVIII or XIX test points apply to various 
portions of the adaptive beam. The agency agreed with many of Ford's 
suggested revisions to the proposed regulatory text and is 
incorporating many of the suggestions into the final rule. The agency 
does not believe that this presents too many cases to test or for a 
manufacturer to certify. While it is true that an ADB system will be 
capable of generating many different adaptive driving beam patterns, it 
is reasonable to require that each beam pattern comply with the 
applicable test points. As with all the FMVSSs, these requirements 
would not require vehicle manufacturers to test every single case, or 
to test at all; they may certify their vehicles using other means. 
Manufacturers must use due care to ensure, however, that the system is 
designed to conform with the FMVSS requirements when tested by NHTSA 
when we use the test procedure specified in the FMVSS.
    With respect to Zoox's comment regarding technological neutrality, 
the agency intends the requirements to be technology-neutral, and 
compatible with ADB systems that use bulbs and shutters, or LED arrays, 
as well as any sensing technology. The requirements do not assume that 
an adaptive beam is a static beam pattern. (As explained above, the ADB 
pattern is dynamic; the laboratory testing will evaluate snapshots of 
the dynamic ADB pattern while the dynamic aspects of ADB are tested 
using the track test). Although the areas of reduced and unreduced 
intensity will be subject to the longstanding lower and upper beam 
laboratory photometric requirements, manufacturers will still have the 
flexibility to design systems that provide a wide array of different 
beam patterns to accommodate not only other cars on the road, but also 
retroreflective signs among other things, and bicyclist and 
pedestrians.
3. Requirements for Area of Reduced Intensity
    The NPRM applied the Table XIX lower beam photometric requirements, 
both minima and maxima, to areas of reduced intensity. This differed 
from SAE J3069, which specifies only the lower beam maxima in this 
area.
Comments
    While Consumer Reports appeared to support requiring the lower beam 
minima in this area, and Intertek supported requiring both the lower 
beam maxima and minima, several commenters contended that if a 
laboratory test was required for the area of reduced intensity, it 
should specify the lower beam maxima (perhaps with some adjustments) 
but not the lower beam minima. (Some commenters argued that the maxima 
above 10

[[Page 9984]]

degrees should not apply. This is discussed in Section VIII.D.6.)
    Volkswagen, SAE, SL, GM, Koito, Mercedes, the Alliance, IIHS, AAA, 
Zoox, and Valeo commented that specifying the lower beam minima would 
limit the ability of ADB systems to reduce glare below current lower 
beam levels. The Alliance further commented that it would restrict 
hardware design, entail separate development programs for different 
markets, and add significant cost. IIHS commented that requiring the 
lower beam minima would effectively create a lower beam ``cutoff'' 
within the area of reduced intensity and mean that drivers of other 
vehicles below the horizontal axis of the ADB headlamps could 
experience excessive glare. IIHS and AAA stated that current lower 
beams produce high levels of glare in common situations such as 
cresting hills, driving on bumpy roads, or the higher headlamp mounting 
height of pickups and many SUVs, and that ADB systems have the ability 
to reduce glare below these levels if the lower beam minima are not 
specified.
    Zoox suggested that market forces would ensure sufficient 
visibility because, in order to avoid customer complaints of lack of 
illumination, manufacturers are unlikely to provide ADB illumination 
below the current lower beam minima. SL commented that the NPRM 
disregarded the upper area of the cut-off line in this region.
Agency Response
    The final rule adopts the proposed requirements for an area of 
reduced intensity, including that it meet the Table XIX minima. NHTSA 
believes requiring an area of reduced intensity to meet the lower beam 
minima is justified because the rule does not include any ``false 
positive'' tests, i.e., tests to ensure that an ADB system does not 
mistakenly dim the beam in the absence of any oncoming or preceding 
vehicles. The sensitivity of the system is largely left to the 
manufacturer to design, provided it responds to the stimulus test 
fixtures in the track test and passes the photometry tests. If a 
manufacturer produces a very sensitive system that shades for things 
that are not actually other vehicles, a beam pattern that provides less 
visibility than a current lower beam would be less safe than the 
current standard. Requiring the lower beam minima be met in the area of 
reduced intensity ensures that the driver will always have a minimum 
amount of light providing adequate visibility.
    NHTSA does recognize that it would likely be possible to revise the 
current lower-beam minima, as applied to ADB systems, to allow for 
reductions in intensity below the currently-required limits without 
risking safety. However, NHTSA does not have data, and no data were 
supplied, that would allow it to establish the minimum size and roadway 
scenario for an area of reduced intensity with less light below the 
cutoff. Without such data, NHTSA does not have a clear basis on which 
to revise or remove the current lower beam minima.
    As some commenters pointed out, requiring the dimmed portion of the 
ADB beam to meet the lower-beam minima means that an ADB system might 
not be able to reduce glare below current levels in some situations. 
This would likely occur in situations, as AAA alludes to, on undulating 
roadways and hills where the ADB vehicle crests a hill and there is an 
oncoming or preceding vehicle in front of it, in which case the lower 
beam minima might coincide with that vehicle. In light of the concerns 
noted above, NHTSA believes that accepting some level of glare in such 
situations--which is already present with current lower beams--is a 
reasonable trade-off to ensure adequate visibility for the driver. This 
will result in disharmonization with the ECE regulations, which permit 
the area of reduced intensity to project intensities below the lower 
beam minima. However, this is justified for the reasons given above. 
Specifying the lower beam minima will result in a situation that is 
unchanged from present, in terms of both safety, costs, and 
disharmonization.
    NHTSA recognizes that market forces are more likely to ensure 
adequate visibility than mitigate glare, thereby potentially obviating 
the need to specify any minima. As noted in the NPRM, ``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.'' 
The agency believes such an argument has merit, and closely considered 
the matter. As more experience is gained with these systems the agency 
may consider modifying or eliminating this requirement. For now, 
however, given the importance of visibility, the agency will err on the 
side of caution and apply the lower beam minima to the dimmed portion 
of the beam.
    Potential issues of glare due to headlamp mounting height on 
pickups and SUVs can be addressed with the on-vehicle aim of the 
headlamps, much as it is currently addressed.\178\ Manufacturers might 
also be able to further minimize glare if they use on-vehicle dynamic 
aiming. In the past, NHTSA has explained that for headlamp systems 
capable of dynamically re-aiming the headlamps (for example, based on 
the steering angle), the laboratory photometry requirements ``must be 
met in the nominal position of the lower beam headlamp (i.e., 
considering the location of the axis of reference to coincide with the 
longitudinal axis of the vehicle).'' \179\ This means, for example, 
that an ADB system that dynamically re-aimed the headlamps downward 
when cresting a hill with an oncoming vehicle (which, in line with 
AAA's comments, is the prime concern motivating the request to not 
apply the lower beam minima) could effectively shift down the dimmed 
area so as not to glare the oncoming vehicle.
---------------------------------------------------------------------------

    \178\ See SAE J599 Lighting Inspection Code.
    \179\ Letter from NHTSA to Kiminori Hyodo, Koito Manufacturing 
Co., Ltd. (Feb. 10, 2006). See also 68 FR 7101 (Feb. 12, 2003) 
(discussing application of laboratory photometry requirements to 
adaptive frontal-lighting systems).
---------------------------------------------------------------------------

    Although the final rule does not disregard the cut-off as suggested 
by SL, the final rule modified the right curve scenarios to consider 
the fact that the Table XIX (lower beam) photometry requirements permit 
greater illuminance on the right side than on the left side.
4. Requirements for Area of Unreduced Intensity
    The NPRM applied the current Table XVIII upper beam photometric 
requirements (both the minima and the maxima) to the area of unreduced 
intensity. This differed from SAE J3069, which specifies the lower beam 
minima and does not specify any maxima.
Comments
    Several commenters (GM, SL, ALNA, Koito, SAE, TSE, Auto Innovators, 
and Texas Instruments) asserted that NHTSA should specify the lower 
beam minima instead of the upper beam minima. SAE commented that SAE 
J3069 intentionally replaced the upper beam minima with lower beam 
minima to assure a performance comparable to the wider lower beam 
versus the narrower upper beam. SAE also stated that specifying the 
lower beam minima would harmonize with ADB systems already in use in 
other regions. Texas Instruments commented that while it might be 
appropriate to require mechanical shutter and low-resolution ADB 
systems to meet the lower beam minima, the proposal would negatively 
impact many of the potential safety

[[Page 9985]]

improvements enabled by high-resolution ABD systems, such as luminous 
intensity optimization on retroreflective street signs and 
differentially illuminating the face and body of a pedestrian. TSEI 
similarly commented that specifying the lower beam minima would provide 
a greater degree of design freedom, and also claimed that requiring the 
system to meet the upper beam minima in the area of unreduced intensity 
(in combination with the requirements for the area of reduced 
intensity) would create potentially insurmountable technical challenges 
because ADB systems require a transition zone between the area of 
reduced intensity and the area of unreduced intensity.
    A few commenters (SAE, GM, and Koito) supported the proposal to 
specify the existing upper beam maxima in the area of unreduced 
intensity.\180\ However, several commenters urged NHTSA to either not 
specify any maxima or, alternatively, to adopt the higher maximum 
allowed by the ECE. These commenters contended that adopting the higher 
maximum would lead to greater safety benefits than the proposed 
specification. Global commented that there are no safety reasons to 
specify the upper beam maxima in the absence of other road users. The 
Alliance commented that the safety benefits of ADB would be limited by 
not allowing ADB systems to exceed the current upper beam maxima, and 
recommended that, if NHTSA decides to specify a maximum, it should 
harmonize with the ECE maximum of 430,000 cd (215,000 per headlamp). It 
contended that, while glare is a concern, it is difficult to determine 
glare as a direct cause to crashes or fatalities, referring to past 
agency reports finding that evidence linking headlamp glare and crash 
risk is difficult to obtain, and noting that the percentage of 
accidents that could be at least partly related to headlamp glare is no 
more than 1%. Notwithstanding the many consumer complaints regarding 
glare noted by the agency, the Alliance stated that it was not aware of 
any agency action to investigate issues related to headlamp glare. On 
the other hand, the Alliance pointed out that in 2012, 70% of 
pedestrian fatalities occurred at night, and by 2016 this had increased 
to 75%. The Alliance also referred to the NPRM discussion that 
referenced a study from the Insurance Institute for Highway Safety 
finding that pedestrian deaths in dark conditions increased 56% from 
2009 to 2016. Volkswagen supported the Alliance's comments and cited 
studies it said showed headlamp intensities exceeding the current FMVSS 
No. 108 upper beam maximum (last updated in 1978) would significantly 
increase visibility and therefore safety. Mercedes also encouraged 
NHTSA to adopt the ECE maximum because it could increase forward 
visibility by 40% compared to the FMVSS No. 108 maximum.
---------------------------------------------------------------------------

    \180\ SAE appears to suggest this approach if NHTSA does not 
adopt a transition zone. As we discuss in Section VIII.D.5, the 
final rule adopts a transition zone.
---------------------------------------------------------------------------

    IIHS commented that, for properly-functioning ADB systems, an upper 
beam maximum was either not necessary or that the higher ECE maximum 
should apply. IIHS stated that the proposal would prevent ADB systems 
from realizing their full visibility-enhancing potential. They stated 
that if NHTSA is concerned that there are scenarios where ADB systems 
may not properly detect and shadow other vehicles, it would be 
preferable to include these in the set of dynamic tests rather than 
limit ADB output to the same level as manually-controlled upper beams. 
AAA commented that European specifications require camera recognition 
and reaction at distances of 400 meters (1,312 feet), and that if ADB 
systems are effective at this distance, the intensity limits could be 
increased to the ECE maximum. It suggested that additional criteria for 
raising the upper beam maximum should include proven ability to quickly 
adapt to changes in vehicle elevation, as result from driving on 
undulating roadways and hills.
Agency Response
    The final rule follows the NPRM and specifies the existing upper 
beam minima, not the lower beam minima. Because ADB systems can detect 
other vehicles, the areas of the beam directed where other vehicles are 
not present should be an upper beam. Because the track test evaluates 
the ability of the ADB system to appropriately recognize and shade 
other vehicles, requiring the upper beam minima should not result in 
glare to other motorists.
    However, NHTSA agrees with the comments about the possible safety-
enhancing effects of allowing manufacturers to shade areas of the 
roadway in addition to those occupied by other vehicles (e.g., 
retroreflective signs). The final rule therefore gives manufacturers 
the flexibility to design an ADB system that provides an area of 
reduced intensity to any area of the roadway, not just areas occupied 
by other vehicles (see Section VIII.D.2). This essentially gives 
manufacturers the flexibility to meet the lower beam minima instead of 
the upper beam minima for any part of the roadway it chooses, and more 
closely harmonizes with SAE J3069. Because we have modified the 
proposal to allow manufacturers the flexibility to provide an area of 
reduced intensity on parts of the roadway that are not occupied by 
other vehicles, they will have the ability to innovate and optimize 
luminous intensity for objects such as retroreflective signs and other 
roadway users. We also believe this will, in conjunction with the 
transition zone allowance, address the transition zone issue (see 
Section VIII.D.5). With respect to SAE's comment about the 
preferability of a wider lower beam, nothing in the final rule prevents 
this wider beam pattern in an area of unreduced intensity. The lower 
beam pattern extends to test points at 20L and 20R, whereas the upper 
beam test points only extend to 12L and 12R.
    The final rule follows the NPRM in specifying the existing Table 
XVIII upper beam maximum for the area of unreduced intensity. NHTSA has 
decided not to adopt the higher ECE upper beam maximum. Table XVIII 
specifies a maximum at H-V of 75,000 cd per headlamp, or 150,000 cd for 
a headlighting system. The purpose of this maximum is to control glare 
that would occur if the upper beam is improperly activated (i.e., when 
other vehicles are within 500 ft) \181\ and to control glare to 
vehicles that are more than 500 ft away, which is the distance outside 
of which most States permit upper beam use.\182\
---------------------------------------------------------------------------

    \181\ 43 FR 32416, 32417 (July 27, 1978) (final rule increasing 
upper beam headlamp intensity to 75,000 cd).
    \182\ 61 FR 54981, 54982 (Oct. 23, 1996) (denial of rulemaking 
petition to increase the upper beam maximum intensity to 140,000 
cd). See also NPRM, p. 51779 n.75. Table XVIII also specifies an 
upper beam maximum at 4D-V. This regulates foreground light that 
affects a driver's ability to see objects far down the road. High 
levels of foreground illumination tend to draw a driver's attention 
away from the distant road scene to the foreground because the 
foreground light appears brighter than the road scene further away. 
In addition, high foreground intensities reduce the ability to see 
dimly illuminated objects further down the road. See 62 FR 31008, 
31010 (June 6, 1997) (denial of petition for reconsideration). The 
magnitude of this maximum is based on the H-V maximum. Because we 
are not adjusting the H-V maximum we do not need to consider the 4D-
V maximum.
---------------------------------------------------------------------------

    While NHTSA agrees with the commenters that brighter upper beams 
would lead to safety benefits in the form of increased visibility in 
the absence of other road users, NHTSA remains concerned about 
potential glare from brighter upper beams in situations in which an ADB 
system might not recognize and shade other vehicles. The final rule 
includes a track test that evaluates an ADB system's ability to 
recognize and shade other vehicles in a

[[Page 9986]]

variety of scenarios. The NPRM proposed an even greater variety of 
scenarios that the agency could test, but many commenters argued that 
the proposed testing was onerous and impracticable. Pursuant to these 
comments, the final rule significantly streamlines the scenarios that 
NHTSA may test. While the final rule includes a sufficient variety of 
track test scenarios to reasonably ensure that an ADB system does not 
glare other motorists, the track test does not include--nor could NHTSA 
feasibly test--every scenario that an ADB system might encounter in the 
real world. Maintaining the current upper beam maximum as a backstop to 
the dynamic tests will help assure that if an ADB system fails to 
properly detect and dim lighting towards another vehicle (whether due 
to topography, sudden appearance, or any other situation that leads the 
ADB system to fail to recognize and shade another vehicle), the system 
will not produce glare beyond what a current FMVSS 108-compliant upper 
beam would.
    If the final rule were to adopt the higher ECE maximum, an 
expansion of the track test scenarios might be warranted to ensure that 
these brighter beam patterns do not glare other motorists. There are at 
least two ways the agency might consider expanding the track test 
scenarios. First, testing the ADB system for glare beyond the 220 m 
proposed and included in this final rule. As explained in the NPRM, 
testing out to 220 m is appropriate because at this distance, the glare 
from an upper beam at the current implied system maximum of 150,000 cd 
would be 3.1 lux, which is equivalent to the glare cutoff implied by 
many State upper beam-use laws.\183\ Adopting the ECE system maximum of 
430,000 cd could justify testing out to 372 m (the distance at which 
430,000 cd equals 3.1 lx.). This is consistent with AAA's suggestion 
that the upper beam maximum could be increased if NHTSA dynamically 
tested headlamp illuminance at ranges of up to 400 meters. Second, 
NHTSA might consider additional test scenarios related to other 
concerns that might be associated with brighter beam patterns. For 
example, as AAA suggested, expanding the track test scenarios might be 
appropriate to ensure that the brighter upper beam does not glare other 
road users, for example, by testing the ability of the system to 
quickly adapt to changes in vehicle elevation.
---------------------------------------------------------------------------

    \183\ See NPRM n. 75 and accompanying text.
---------------------------------------------------------------------------

    NHTSA, however, is not currently prepared to expand the track test 
scenarios in this way. In order to extend the distances at which we 
evaluate glare in the track test, the agency would likely want to 
consider, among other things, the appropriate glare limits at those 
distances and whether the existing test procedures would need to be 
modified to accommodate greater testing distances (for example, the 
availability of test tracks with those distances).\184\ Further 
research might also include the development of additional test 
scenarios appropriate for higher-intensity headlamps.\185\ In short, 
NHTSA is not currently prepared to make any further changes to the 
proposal related to a brighter upper beam. The goal of this rulemaking 
is to extend the existing photometry requirements to enable the safe 
introduction of ADB systems, and to expeditiously finalize this rule to 
enable deployment of ADB systems.
---------------------------------------------------------------------------

    \184\ The research on which the track test requirements are 
based developed those requirements and test procedures only for 
testing glare--commensurate with the current FMVSS No. 108-compliant 
upper beams--out to 220 m, not at the greater distances that would 
be necessary with ECE-approved upper beams.
    \185\ NHTSA's earlier research did include some testing related 
to ADB performance on hills. However, such scenarios were not 
proposed because of relatively poor ADB system performance in those 
trials. See 2105 ADB Test Report at p. 102.
---------------------------------------------------------------------------

    Because NHTSA is not prepared to extend the test requirements to 
ensure that ADB systems with a higher maximum intensity would operate 
safely, increasing the photometric maximum, without also adding such 
additional test requirements, would result in a situation where glare 
past 220 m was not regulated. Some commenters stated that there is 
insufficient data to conclude that the disbenefits from glare at these 
distances outweigh the benefits from greater visibility and pointed to 
the increase in pedestrian fatalities. NHTSA agrees that evidence 
linking headlamp glare and crash risk is difficult to obtain, that 
there are benefits to increased visibility, and that there has been an 
increase in pedestrian fatalities. However, we note that NHTSA has 
previously declined to increase the upper beam maximum beyond 150,000 
cd to the ECE maximum because of a lack of data on whether any 
improvements would outweigh any associated disbenefits associated with 
potential increases in glare.\186\ We are not aware of any compelling 
new research on the issue, and the comments did not identify any such 
research. Accordingly, we have no reason to revise our previous 
conclusions that the current upper beam maximum appropriately balances 
the benefits of visibility and the disbenefits of glare. In short, 
NHTSA is presently unable to conclude that more than doubling the 
maximum permitted intensity from 75,000 cd to 215,000 cd (per headlamp) 
would provide a significant enough advantage to warrant risking the 
potential negative externalities of glare.\187\ Nevertheless, ADB 
systems will still provide increased visibility outside of the area of 
reduced intensity, as well as increase upper beam use, which will help 
prevent crashes.
---------------------------------------------------------------------------

    \186\ Most recently, in 2009 NHTSA denied a petition for 
rulemaking from The Groupe de Travail ``Bruxelles 1952'' and SAE to 
amend FMVSS No. 108 to, among other things, increase the upper beam 
maximum to 140,000 cd. 74 FR 42639 (Aug. 24, 2009). NHTSA declined 
to increase the maximum because of a lack of data to allay the 
concern that the benefits due to increased visibility might be 
outweighed by the disbenefits from increased glare. Similarly, when 
NHTSA increased the (implied) system-level upper beam maximum from 
75,000 to 150,000 in 1978, it referred to contemporaneous research 
``demonstrating that an increase in photometrics to a maximum of 
150,000 cp will enhance seeing ability without any significant 
increase in glare form properly aimed headlights, but that 
photometric output exceeding 150,000 cp results in only a marginal 
increase in visibility with an increase in glare.'' 43 FR 32416 
(July 27, 1978). See also 61 FR 54981 (Oct. 23, 1996) (denial of 
rulemaking petition to increase upper beam system-level maximum to 
140,000 cd) (citing the 1978 rulemaking notice and stating that 
``the agency has done no similar research work on upper beam 
headlamps since then nor is it aware of other safety research in 
this area'').
    \187\ While we agree with the Alliance that adopting the ECE 
maximum would enhance harmonization, we still believe that there is 
a headlamp harmonization window. See 61 FR 54981.
---------------------------------------------------------------------------

5. Transition Zone
    The NPRM applied the Table XIX lower beam photometric requirements 
to areas of reduced intensity and the Table XVIII upper beam 
photometric requirements to areas of unreduced intensity. The NPRM did 
not provide for a transition zone between areas of reduced and 
unreduced intensity.
Comments
    Many commenters (SAE, ALNA, the Alliance, Global, Valeo, Honda, SL, 
Stanley, Koito, Mercedes, Volkswagen, Toyota, and TSEI) pointed out 
that the proposed photometric requirements could not be met without 
allowing for a transition zone between the areas of reduced and 
unreduced luminous intensity. Mercedes, Volkswagen, Toyota, Auto 
Innovators, and TSEI specifically agreed with SAE's comments on this 
issue.
    SAE commented that a transition zone can only be minimized, not 
eliminated, and because the transition between reduced and unreduced 
areas does not comply with either upper or lower beam photometry it 
must be eliminated in the photometric testing. Without a transition 
zone, an ADB system would

[[Page 9987]]

be expected to modify its illumination from very low light levels to 
above 40,000 cd over a zero angle, which is physically impossible. SAE 
gave an example of an area of reduced intensity around the upper beam 
minimum at 1U, 3L, with the edge of the area of reduced intensity to 
the left of 3L, and the area of unreduced intensity at 3L. SAE pointed 
out that in this example, the upper beam minimum of 5,000 cd and lower 
beam maximum of 700 cd (at 1.5 U, 1.5 L to L) are impossible to 
coincidentally satisfy, even with the 0.25 degree re-aim allowance in 
FMVSS No. 108, because the transition from the unreduced intensity to 
the reduced intensity is much larger than 0.25 degrees. To illustrate 
this, SAE provided a horizontal scan through an ADB headlamp beam 
pattern showing a transition zone of greater than 1 degree for the 
minimum at (1U, 3L) to be met. SAE noted that similar issues will occur 
in other parts of the beam pattern. Toyota similarly commented that the 
absence of a transition zone leads to a distinctive vertical line 
between the area of reduced intensity and the area of unreduced 
intensity. It has been Toyota's experience that a sharp cutoff 
distracts drivers and leads to customer complaints that the sharp 
cutoff reduces visibility over bumps, dips, and twisty roads. Toyota 
also noted that ADB systems it sells in other markets include a 
transition zone and it has received positive consumer feedback.
    There were a variety of comments related to how the agency might 
account for a transition zone in the final rule. SAE suggested that the 
transition zone be ``disregarded.'' SAE recommended several different 
alternative modifications to the proposal if final rule were not to 
disregard the transition zone. These included specifying only the lower 
beam maximum values in the area of reduced intensity, and not minimum 
values; excluding the boundaries of 10U to 90U from the lower beam 
maxima requirements; specifying the lower beam minima instead of the 
upper beam minima in the area of unreduced intensity; and modifying the 
regulatory text by adding ``fully'' before the text describing the area 
of reduced intensity. SAE also recommended reorganizing the regulatory 
text of S9.4.1.6.6-.7.\188\ Some of SAE's suggestions were echoed by 
other commenters. Global suggested that the final rule should allow for 
a mid-beam independent of the lower or upper beam. SL suggested that 
the manufacturer be permitted to set the boundary area or that the 
final rule should specify light intensity criteria for the transition 
zone.
---------------------------------------------------------------------------

    \188\ SAE stated that these recommendations are also intended to 
address the veiling glare issue. See Section VIII.D.6, Veiling 
Glare.
---------------------------------------------------------------------------

Agency Response
    NHTSA agrees with commenters that the final rule should allow for a 
transition zone between areas of reduced and unreduced intensity. The 
final rule allows for a 1-degree transition zone between an area of 
reduced intensity and an area of unreduced intensity, within which the 
Table XVIII and XIX requirements will not apply, except that the 
maximum at H-V in Table XVIII as specified in Table II for the specific 
headlamp unit and aiming method may not be exceeded at any point in a 
transition zone. Manufacturers essentially will be free to determine 
the areas of reduced and unreduced intensity and, therefore, the 
boundaries of the transition zone. In addition, the vehicle will still 
need to pass the track test.
    In considering how to account for a transition zone NHTSA consulted 
photometric requirements specified in other technical standards and 
comparable foreign regulations. Because SAE J3069 does not explicitly 
define or identify a transition zone,\189\ the agency researched 
references to aiming tolerances in other SAE-recommended practices for 
headlamps. J2838 Full Adaptive Forward Lighting Systems specifies 
aiming procedures for adaptive lighting systems. Section 6.5 includes 
provisions for adjusting vertical and horizontal aim, including 
expected aiming tolerances, and provides for a +/- 0.5 degree (or 1 
full degree) vertical tolerance to transition between the lower beam 
zones and the upper beam zones. The J2838 procedures, though not 
specifically for a transition zone, suggest that a similar 1 degree 
transition between areas of reduced and unreduced intensity in an 
adaptive driving beam pattern would be appropriate.
---------------------------------------------------------------------------

    \189\ SAE J3069 MAR2021 added a definition for the transition 
zone (``The area in the ADB where the unreduced intensity 
transitions to the non-glare zone''). It states that the prior 
version assumed the existence of a transition zone and that this 
definition was added for clarity. The transition zone allowed in 
this final rule is similar in concept, but is more specific in order 
to provide a more objective test procedure for the purposes of 
compliance testing.
---------------------------------------------------------------------------

    This is consistent with the ECE requirements for adaptive front 
lighting systems. NHTSA could not find reference to a direct 
specification of a transition zone in either ECE R.48 or R.123. Section 
6.22.6.3 of R.48 does, however, specify a +/- 0.5 degree tolerance for 
the cutoff of a lower beam. Similarly, Section 6.3.5 of R.123 specifies 
a +/- 0.5 degree vertical and +/- 1 degree horizontal tolerance for 
aiming of systems prior to testing to ensure photometric requirements 
are met for ADB systems. Annex 8 of R.123 cites the same cutoff and 
aiming provisions cited in SAE J2838 mentioned above.
    A 1 degree transition should resolve the concerns of and be 
consistent with the information presented by the commenters. SAE raised 
the example of an adaptive driving beam pattern with an area of reduced 
intensity with vertical cutoffs around 3L and 6L.\190\ As SAE pointed 
out, there is an upper beam minimum of 5,000 cd at 1U 3L and a lower 
beam maximum of 700 cd from 1U-1.5 L to L. As SAE also correctly 
pointed out, it would impossible for an adaptive driving beam with an 
area of reduced intensity with a vertical cutoff around 3L to 
simultaneously satisfy both the upper beam minimum and the lower beam 
maximum without a transition zone. A 1 degree transition zone resolves 
this issue and gives the system room to gradually modify the intensity. 
The data presented by SAE \191\ shows that a real-world ADB system 
could comply with the final requirements: The upper beam minimum at 1U 
3L would fall within the transition zone, and the area of reduced 
intensity would comply with the lower beam maximum. SAE's example also 
indicates that 1 degree is sufficient for a cutoff between an area of 
unreduced intensity and an area of reduced intensity because it shows 
that it takes the beam less than 1 degree to transition from 
intensities characteristic of an upper beam (e.g., 5,000 cd) to 
intensities characteristic of a lower beam (e.g., 700 cd). In addition 
to the transition zone, the existing provision (in S14.2.5.5) for a 
0.25 degree re-aim in any direction at any test point would also apply. 
NHTSA believes that this specification for a transition zone, together 
with allowing manufacturers the flexibility to project an area of 
reduced intensity on areas of the roadway other than oncoming and 
preceding vehicles, also resolves the other concerns raised by the 
commenters.
---------------------------------------------------------------------------

    \190\ SAE comment (NHTSA-2018-0090-0167), p. 6 (Fig. 2).
    \191\ Id.
---------------------------------------------------------------------------

6. Veiling Glare
    The NPRM extended the Table XIX lower beam photometric requirements 
to areas of reduced intensity. These include a maximum of 125 cd in the 
region of 10U to 90U and 90L to 90R.

[[Page 9988]]

The purpose of these test points controlling veiling glare is to limit 
back-scatter in environmental conditions such as fog, mist, and snow.
Comments
    Some commenters opposed applying the veiling glare limits to the 
area of reduced intensity. ALNA commented that these maxima are not 
necessary because the increased safety provided by an ADB system 
justifies less strict self-glare (back-scatter) requirements. SAE 
commented that if the final rule did not include a transition zone, the 
area from 10U to 90 U should be excluded from photometric testing 
because light from areas of unreduced intensity can fall into the area 
of reduced intensity, exceeding the veiling glare requirement in the 
10U to 90U zone. GM commented similarly.
Agency Response
    The concerns the commenters expressed about the veiling glare 
limits are addressed by two of the modifications to the proposal. 
First, as explained in the preceding section, in response to the 
comments the final rule added a transition zone between areas of 
reduced and unreduced intensity. Second, the final rule modifies the 
proposal to give manufacturers the flexibility, in designing the 
adaptive beam, to illuminate portions of the roadway other than those 
occupied by oncoming or preceding vehicles with either an area of 
reduced intensity or area of unreduced intensity. An adaptive beam may 
therefore provide an area of unreduced intensity that covers the 
entirety of the 10U to 90U region, for which the Table XVIII upper beam 
requirements do not contain any test points. NHTSA believes that these 
modifications resolve the commenters' concerns about veiling glare 
exceedances.\192\
---------------------------------------------------------------------------

    \192\ SAE J3069 MAR2021 excludes the boundaries of 10U to 90U 
and 90L to 90R from the requirement in that practice that the non-
glare zone (area of reduced intensity) meet the lower beam maximum 
values specified in SAE J1383. The modifications to the proposal are 
consistent with this.
---------------------------------------------------------------------------

E. Minimum Activation Speed

    The NPRM proposed that an ADB system must produce a lower beam 
below 25 mph, explaining that since the primary purpose of ADB is to 
provide additional light at relatively higher speeds, it may be likely 
that the potential disbenefits from glare outweigh the potential 
benefits from additional illumination at lower speeds.
Comments
    One commenter, Consumer Reports, supported requiring the lower beam 
as a default any time the vehicle is traveling at a speed below 25 mph 
in order to limit glare in circumstances where upper beams are not 
intended for use.
    Other commenters, however, disagreed with the proposal. Toyota, 
Honda, and Ford stated that there should be no speed restriction on ADB 
activation. SAE, Koito, Valeo, Zoox, and Volkswagen asserted that ADB 
operation should not be restricted to 25 mph and above. Texas 
Instruments and Harley Davidson commented that ADB activation below 25 
mph should be allowed in certain circumstances. The commenters made a 
variety of arguments in support of these positions.
    Some commenters suggested that the benefits of allowing ADB at 
lower speeds outweighed any potential glare disbenefits. SAE stated 
that the potential disbenefits from glare would be mitigated as ADB 
systems become more advanced and able to recognize and respond 
appropriately in low speed-environments. Honda commented that there is 
a safety need for visibility at lower speeds and calculated that, based 
on 2011 to 2016 GES data for pedestrian accidents, approximately 40% of 
nighttime accidents occur when the vehicle speed is estimated to be 
under 25 mph (when the vehicle speed can be estimated). Toyota 
commented that there are not any data that show a safety need to 
regulate the activation speed.
    SAE commented that there is no single driving speed where the 
benefits of ADB disappear to the point where automatic deactivation 
should be required. They stated that changes in the driving environment 
are not necessarily correlated with vehicle speed and it is the changes 
in driving environment where the driver most benefits from an adaptive 
driving beam. (Honda had a similar comment.) SAE asserted that sudden 
deprivation of light based only on a specific speed threshold presents 
potential safety risks and is contrary to the purpose of ADB. Toyota 
stated that there was customer demand for ADB to be operable in urban 
areas and in residential areas where visibility can be extremely low 
and the speed limit is typically 25 mph, and believed it can provide 
safety benefits, especially because there is a higher probability for 
drivers to interact with pedestrians or cyclists in these areas. Honda 
commented that ADB should provide active forward illumination under 
certain environmental lighting conditions to address safety needs.
    Valeo, Toyota, and Ford suggested that there should be no speed 
limitation because FMVSS No. 108 contains no such speed restriction for 
semiautomatic beam switching devices. SAE, Valeo, and Ford similarly 
stated that FMVSS No. 108 does not contain a speed threshold for manual 
switching between lower and upper beams. SAE commented that a 
deactivation threshold speed of 25 mph may also encourage drivers to 
exceed this speed where it is the posted limit or when road conditions 
warrant lower speeds in order to maintain activation of the adaptive 
driving beam. SAE also commented that if drivers want to override ADB 
operation they can do so manually.
    Zoox recommended that the agency consider reducing the minimum 
speed to 20 mph so ADB use would be available for lower-speed city use, 
especially to see pedestrians and cyclists on the roadway shoulder. 
Texas Instruments commented that high-resolution ADB systems can change 
this perceived disbenefit/benefit relationship, and that NHTSA should 
exempt high-resolution systems to allow innovative uses of hazard 
marking applications in urban settings.
    Harley Davidson commented that activation of the adaptive beam 
below 25 mph should be allowed on motorcycles because they lean during 
cornering and use the upper beam for more than just additional light 
down the road. They claim that the beam pattern projected from a 
leaning motorcycle differs significantly from the beam pattern of a 
four-wheel vehicle, and that this is particularly pronounced during 
low-speed maneuvering where the vehicle dynamics required to maneuver 
through a 90-degree intersection often results in a more severe lean of 
the vehicle than required during higher speed turns with a larger turn 
radius. They claimed that when traffic conditions allow, motorcycle 
riders use the upper beam during these low-speed maneuvers to take 
advantage of the enhanced illumination in the direction the rider is 
looking. Harley Davidson further contended that motorcycle cornering 
lighting systems have been developed to enhance the lower beam 
illumination during vehicle leaning, and that ADB systems are 
potentially an enhancement to current systems, which are can operate at 
all speeds.
Agency Response
    After considering the comments, NHTSA has decided to retain a 
minimum activation speed, but has

[[Page 9989]]

lowered it to 20 mph to give greater flexibility to manufacturers 
wishing to provide a hysteresis in the system design. (Hysteresis is 
the difference in the activation or deactivation speed of the system 
based on whether the vehicle is increasing or decreasing speed.)
    NHTSA believes that lower beams generally provide adequate 
visibility at speeds below 25 mph, given typical driver reaction time 
and vehicle stopping distances. This is consistent with the information 
that Toyota provided in its petition for rulemaking, which indicated 
that lower beams provide sufficient illumination up to about 30 mph (or 
about 160 ft).\193\ This is also consistent with many of the ADB 
systems NHTSA tested, which had activation speeds between 20 mph and 40 
mph and deactivation speeds from 15 mph to 25 mph.\194\ A more recent 
model NHTSA tested (a MY 2018 Lexus NX built for the European market) 
had three ADB modes, and the lowest activation speed was 9 mph (with a 
deactivation speed of 7.5 mph).
---------------------------------------------------------------------------

    \193\ Toyota rulemaking petition, Appendix C. Consumer Reports, 
in its comment, estimated a longer lower beam seeing distance (300 
ft) but still supported the proposed minimum activation speed.
    \194\ 2015 ADB Test Report, p. 91.
---------------------------------------------------------------------------

    A 20 mph activation speed is also supported by research on glare 
and driving performance. In 2008 NHTSA published a summary of this 
research and found that in areas with high ambient light levels such as 
city downtown areas, lower-beam headlamps provide sufficient visibility 
because driving speeds are lower in urban areas (i.e., under 30-40 mph) 
and because ambient light levels (from street lighting or other 
sources) are usually higher; the study also noted that lower beam 
intensities might even be able to be reduced in these areas to reduce 
glare to other drivers without strongly affecting forward 
visibility.\195\ This is also consistent with NHTSA's data on nighttime 
crashes involving pedestrians and cyclists.
---------------------------------------------------------------------------

    \195\ DOT HS 811 043 (2008) at I-9 (citing and discussing 
research).
---------------------------------------------------------------------------

    Even if increased illumination at speeds under 20 mph were to 
result in incremental benefits,\196\ omitting a minimum activation 
speed could require expanding the dynamic track test scenarios to 
evaluate ADB performance in the types of environments (e.g., urban) and 
situations (e.g., intersections) associated with these lower speeds. 
This is particularly important because the early ADB systems tested 
were not able to pass low-speed scenarios such as intersection 
scenarios.\197\ While it is likely true that the capabilities of ADB 
systems have advanced since then--including but not limited to the 
development of high-resolution systems--that does not obviate the need 
for testing. However, the agency has not yet proposed or fully 
developed the appropriate test scenarios to evaluate ADB performance in 
these types of environments and speeds. To do so, NHTSA would have to 
consider a number of factors, such as the relevant scenarios for 
testing. Because such test scenarios have yet to be developed, the 
agency is currently unable to test whether ADB systems would create 
glare in those situations. Development of such test scenarios would 
take additional time and resources. In the interests of facilitating 
ADB deployment--especially in situations (i.e., at speeds over 20 mph) 
at which it will provide the most benefit--NHTSA believes it is 
expedient to finalize a rule with a minimum activation speed instead of 
developing such additional test scenarios.
---------------------------------------------------------------------------

    \196\ See id., p. I-9 (``Modifications to low beam patterns have 
been suggested and demonstrated to provide incremental benefits in 
terms of visibility, but light levels comparable to those from 
typical high beam headlamps appear to be desirable in terms of 
forward lighting, particularly for faster driving speeds. Yet these 
same light levels would almost certainly be undesirable by drivers 
facing them in nighttime driving situations.'').
    \197\ See 2015 ADB Test Report, p. 172 (``All of the ADB systems 
produced considerably more glare in intersection scenarios than was 
seen with lower beam mode.'').
---------------------------------------------------------------------------

    Because NHTSA is not extending the testing scenarios to include 
typical low speed/urban environment scenarios, allowing ADB activation 
at these lower speeds would allow glare in these situations to be 
essentially unregulated. A few commenters suggested that the likely 
benefits from enhanced visibility in these situations outweighed the 
potential disbenefits from glare, or that ADB systems would be able to 
mitigate any potential disbenefits from glare at lower speeds. However, 
in light of the studies indicating that lower beams generally provide 
adequate visibility at speeds under 25 mph and NHTSA's testing showing 
that ADB systems may not yet reliably adapt to lower-speed scenarios, 
the agency is not yet confident that any possible incremental benefits 
to increased illumination (above present lower beam levels) below 20 
mph would be likely to offset the possible disbenefits due to 
glare.\198\
---------------------------------------------------------------------------

    \198\ While there are no speed limitations in the current 
requirements for semiautomatic beam switching devices (which date to 
the 1960s), we believe that a minimum speed is justified for ADB 
systems for the reasons given above. Such a requirement may or may 
not also be appropriate for conventional semiautomatic beam 
switching devices, but such a requirement is out of the scope of 
this rulemaking, which is focused on ADB systems. However, we also 
note that ADB systems differ from conventional semiautomatic beam 
switching devices because ADB systems provide more illumination than 
a lower beam. We similarly note that the fact that there are no 
current speed limitations on manual upper beam use is not relevant, 
because ADB is automatic, not manual.
---------------------------------------------------------------------------

    If a driver desires additional illumination at speeds under 20 mph, 
the driver can manually switch to the upper beam mode. This balances 
the concerns of glare and visibility better than (as suggested in the 
comments) allowing activation of the adaptive beam below 20 mph and 
relying on the driver to manually override the ADB and activate the 
lower beam if that would be more appropriate (and the ADB system does 
not automatically switch). This is both because such situations will be 
relatively infrequent and because glare is a negative externality 
\199\--that is, the driver has more incentive to switch to upper beam 
mode to obtain more visibility in the relatively rare situations in 
which it is needed at lower speeds than to override the adaptive beam 
and switch to lower beam mode to avoid glaring others. Commenters did 
not provide data supporting their contention that specifying a minimum 
activation speed will encourage drivers to exceed the minimum 
activation speed in order to maintain ADB operation; drivers that 
recognize they lack adequate visibility can switch to upper beam mode. 
The agency expects this to be more likely than a driver increasing 
speed when they feel that the headlamps are not providing enough 
visibility.
---------------------------------------------------------------------------

    \199\ A negative externality occurs when one party's actions 
impose uncompensated costs on another party. Glare is a negative 
externality because motorists exposed to glare are uncompensated for 
the disability or discomfort they experience.
---------------------------------------------------------------------------

    NHTSA has decided not to allow a lower activation speed for 
motorcycles. Riders are provided a manual switch that activates the 
upper beam in situations where the rider recognizes the need for 
additional lighting. As such, the factors to consider for motorcycles 
are the same as those for other motor vehicles discussed above.

F. Operator Controls, Indicators, Malfunction Detection, and Operating 
Instructions

    The NPRM included a variety of system requirements for ADB systems 
that were either extensions of existing requirements for semiautomatic 
beam switching devices or new requirements that would apply only to ADB 
systems. These included requirements for controls, telltales, and 
malfunction detection. Manufacturers would be free to devise 
supplemental telltales as long

[[Page 9990]]

as they did not impair the required elements.
    The NPRM proposed extending existing semiautomatic beam switching 
device requirements for manual override, fail-safe operation,\200\ and 
an automatic referred dimming indicator to apply both to conventional 
semiautomatic beam switching devices (classified in the proposed 
regulatory text as ``Option 1'' systems) and adaptive driving beam 
systems (to as ``Option 2'' systems). With respect to the manual 
override requirements, the proposal extended the current requirement 
that a semiautomatic beam switching device include a convenient means 
for the driver to switch beams. With respect to the automatic dimming 
indicator requirement, the proposal followed the approach taken in SAE 
J3069.\201\ The NPRM proposed requiring a telltale informing the driver 
when the ADB system is activated.\202\ The agency tentatively decided 
against following the approach of ECE Regulation 48, which requires the 
upper beam telltale be used to indicate ADB activation, because the 
NPRM did not classify the adaptive driving beam as an upper beam. The 
NPRM also did not propose requiring a telltale indicating an enabled 
ADB system is projecting an adaptive driving beam because providing the 
driver with a visual indication of the type of beam an ADB system is 
providing is not necessary for safe driving and could distract the 
driver. For similar reasons, the NPRM also proposed revising the 
existing upper beam indicator requirement in S9.5 to state that the 
upper beam indicator need not activate when the ADB system is 
activated.
---------------------------------------------------------------------------

    \200\ The regulatory text in FMVSS No. 108 has long used the 
unhyphenated ``fail safe.'' To maintain continuity, this final rule 
maintains that spelling in the regulatory text.
    \201\ SAE J3069 S6.8 and discussion at p. 2.
    \202\ We note that the automatic dimming indicator (indicating 
that the semiautomatic beam switching device is controlling the 
headlamps automatically) is different than the upper beam indicator 
(indicating that the upper beams are activated).
---------------------------------------------------------------------------

    NHTSA also proposed adopting additional requirements with no 
analogs in the current semiautomatic beam switching device 
requirements. The NPRM proposed that the ADB system must be capable of 
detecting system malfunctions (including but not limited to sensor 
obstruction); notify the driver of a fault or malfunction; and disable 
the system until the fault is corrected. Most of these are also 
specified in SAE J3069.
    NHTSA also identified and sought comment on a requirement in Table 
I-a that might affect design choices for the headlamp and/or ADB 
controls. This requirement states the ``wiring harness or connector 
assembly of each headlighting system must be designed so that only 
those light sources intended for meeting lower beam photometrics are 
energized when the beam selector switch is in the lower beam position, 
and that only those light sources intended for meeting upper beam 
photometrics are energized when the beam selector switch is in the 
upper beam position, except for certain systems listed in Table II.'' 
This could mean that the headlamp and ADB controls could not be 
designed so the ADB system is activated when the beam selector switch 
is in the lower beam position, because the adaptive driving beam might 
utilize upper beam light sources, which would violate Table I-a because 
upper beam light sources would be activated when the beam selector 
switch is in the lower beam position.
Comments
    NHTSA received several comments on the manual override 
requirements. The United Drive-In Theatre Owners Association and a 
number of drive-in theatre owner/operators asked that ADB systems be 
required to provide manual deactivation. Many of these commenters 
expressed concern that ADB systems could interfere with the enjoyment 
of drive-in movies. Consumer Reports also recommended applying the 
manual override requirement to ADB systems. One commenter (Victor Hunt) 
suggested requiring a warning to the driver when the ADB system has 
been manually overridden. Ford and Zoox suggested modifying the manual 
override regulatory text. Both commenters noted that under the current 
standard, when only lower beams and upper beams are provided, switching 
to ``the opposite beam'' is clear since there are only two options. 
However, when ADB is additionally provided it becomes less clear, 
because ADB essentially introduces a third beam. To address this, Ford 
recommended deleting the reference to the ``opposite'' beam in 
S9.4.1.2. Zoox recommended that this requirement apply only to systems 
certified to S9.4.1.5.The proposed fail-safe requirements (which 
mirrored the current regulatory text) required simply that a failure of 
the automatic control portion of the device must not result in the loss 
of manual operation of both upper and lower beams. Consumer Reports 
supported applying the existing requirements to ADB systems. Global and 
Subaru recommended that the system should fail-safe to the upper beam 
mode, while Zoox suggested requiring the system to default to a lower 
beam until the fault is corrected.
    Global and AAA commented on the wiring harness requirement. Global 
stated that this might adversely affect design choices because it could 
mean that the ADB system may not be activated when the beam selector 
switch is in the lower beam position. To address this, Global 
recommended adding an exception for ADB systems to Table I-a. Global 
alternatively recommended that there could be three operational modes 
that a driver could choose: Lower beam, upper beam, and adaptive 
driving beam. AAA recommended amending Table I-a to account for 
distributed control modules and recommended amending the regulatory 
text so that the current language applies to distinct light sources, 
which by design operate independently, and adding additional language 
that the requirement is not applicable to headlamp beam systems that 
are controlled at the headlamp component level.
    Ford supported not requiring the upper beam indicator to be 
activated when the ADB system is activated because Ford believed it 
would be distracting for driver, is unnecessary because ADB is designed 
not to glare, and harmonizes with SAE and Canada. Consumer Reports 
agreed with extending the existing automatic dimming indicator 
requirements to ADB systems and agreed that an indicator for the type 
of beam ADB is providing or the upper beam indicator should not be 
required. AAA also supported the proposed requirements for telltale 
indicators and supported the focus on reducing driver distraction and 
encouraged that additional indicators be designed so as not to 
contribute to driver distraction.
    Consumer Reports agreed with the additional operational 
requirements in FMVSS No. 108 for ADB systems to detect system 
malfunctions (including sensor obstruction), notify the driver of a 
fault or malfunction, and automatically disable the system until any 
detected fault is corrected. Subaru recommended that S9.4.1.6.2 be 
amended to clarify that the ADB disablement requirement is only 
applicable for non-mechanical failures because, if a mechanical portion 
of the ADB system fails, the fault will not be able to be corrected 
because the mechanism will be unable to function mechanically.
    Zoox suggested edits to the regulatory text, commenting that 
S9.4.1.3, S9.4.1.6.1 and S9.4.1.6.2 are very similar and may be 
duplicative. It recommended that a system certified to

[[Page 9991]]

S9.4.1.5 must meet S9.4.1.3 for fail-safe operation, while a system 
certified to S9.4.1.6 must meet S9.4.1.6.1 and .2 for fail-safe 
operation. Further, instead of using ``shall work in manual mode'' in 
S9.4.1.6.2, Zoox suggested the following alternatives to accommodate 
both human and AI drivers: ``if a manual mode is provided, the lighting 
system shall work in manual mode. . .'' or ``the lighting system shall 
permit control of the beam(s) by the driver until the fault is 
corrected.''
    Brent Peterson commented that upper beam light often creates 
detrimental back scatter under certain weather conditions (e.g., fog or 
rain) and that the driver may not know how to respond.
Agency Response
    NHTSA agrees that a manual override is necessary and, as proposed, 
is extending the manual override requirements to ADB systems.
    The final rule does not require a specific warning when the driver 
chooses to switch the beam from the one provided by the ADB system. 
Because switching from the beam provided is an action initiated by the 
driver, a warning seems unnecessary because the driver would presumably 
know the action was initialized and the required automatic dimming 
indicator would indicate that the ADB system is no longer active. The 
final rule does not prohibit such a warning, provided the warning does 
not interfere with the functionality of the upper beam indicator.
    NHTSA agrees with Ford and Zoox's suggested changes to the manual 
override requirements. The regulatory text incorporates Ford's 
recommended language (``The device must include a means convenient to 
the driver for switching the beam from the one provided.'') The agency 
believes this language provides sufficient flexibility for switch 
design while ensuring that the driver is provided control over beam 
switching for situations where the ADB system does not provide what the 
driver needs for visibility and glare prevention. NHTSA is also 
similarly amending the definition of ``semiautomatic beam switching 
device'' to reflect the fact that the final rule adopts ``adaptive 
driving beam'' as a third type of beam, and have amended that 
definition to clarify that when a semiautomatic beam switching device--
whether or not an ADB system (i.e., certified to either Option 1 or 
Option 2)--is in manual mode, the driver may obtain either the lower 
beam or upper beam.\203\
---------------------------------------------------------------------------

    \203\ The term ``manual'' in this definition, as well as in 
S9.4.1.2 and S9.4.1.3, has a general meaning that encompasses both 
hand-operated and foot-operated controls. See S9.4 (``Each vehicle 
must have a means of switching between lower and upper beams 
designed and located so that it may be operated conveniently by a 
simple movement of the driver's hand or foot.'').
---------------------------------------------------------------------------

    The final rule does not adopt the commenters' suggested changes to 
the fail-safe requirements but gives the manufacturer the flexibility 
to determine whether the ADB system defaults to the lower or upper beam 
in the event of an ADB system failure. Requiring an ADB system to 
default to an upper beam would not ensure that other roadway users are 
not glared; if, however, the ADB system were required to default to the 
lower beam, visibility could be diminished. Because the appropriate 
beam depends on a variety of situation-specific factors (e.g., presence 
of other roadway users, the speed of the ADB vehicle, overall 
visibility)--reflected in the conflicting comments on what the 
appropriate fail-safe should be--NHTSA is giving manufacturers the 
flexibility to determine the appropriate system response.
    NHTSA has adopted Global's suggestion and added to Table I-a an 
exception for ADB systems. The simultaneous activation of a full lower 
beam and a full upper beam will continue to be prohibited for ADB 
systems \204\ (except momentarily in certain situations and except for 
certain systems listed in Table II \205\). The final rule does not 
adopt AAA's suggestion to account for distributed control modules 
because the current language is sufficiently clear to apply to both 
traditional wiring as well as serial communication between the vehicle 
and the headlamps. For example, with respect to powering the headlamp, 
S14.2.5.4 specifies that headlamps are tested at 12.8 V-DC as measured 
at the terminals of the lamp. This provision applies whether the 
terminals of the lamp are also the terminals of the light sources or 
the headlamp distributes this power to the appropriate light sources 
(whether integral beam headlamp sources or replaceable light sources). 
In essence, the wiring harness or connector assembly requirements 
listed in Table I-a and Table I-c are the same whether they apply to 
the basic vehicle wiring harness, or to the internal wiring within the 
headlamp as instructed by the ADB system through a serial line.
---------------------------------------------------------------------------

    \204\ For an ADB system in manual mode, for which the only beams 
permitted are lower and upper beams, simultaneous activation of 
lower and upper beams (subject to some limited exceptions) is 
prohibited by the current language in S9.4, which requires that 
``except as provided by S6.1.5.2, the lower and upper beams must not 
be energized simultaneously except momentarily for temporary 
signaling purposes or during switching between beams.'' However, to 
make this clear, we have added a cross-reference to S9.4 in S4 in 
the ADB requirements. For an ADB system in automatic mode, we have 
also clarified that the system may only switch between lower, upper, 
and adaptive driving beams and may not simultaneously activate any 
of those beams.
    \205\ See S6.1.5.2, S9.4, Table I-a, and Table II.
---------------------------------------------------------------------------

    The final rule adopts the proposed telltale and malfunction 
provisions. With respect to the telltale requirements, we have 
clarified the proposal by requiring that the driver be provided with a 
visible warning that an ADB system malfunction exists. With respect to 
the malfunction provisions, the final rule does not adopt Subaru's 
suggested changes to the malfunction requirements. If the ADB system is 
not able to operate safely in automatic mode due to a malfunction, the 
automatic mode should be deactivated, regardless of whether the 
malfunction is mechanical. We have modified the proposed regulatory 
text to make clear that the system is not required to be deactivated if 
the malfunction does not prevent the system from operating in automatic 
mode safely and in conformance with the requirements applicable to such 
systems. The proposal would have required that, in the event of a 
malfunction, the ADB system must be ``disabled.'' However, in order to 
be less design restrictive, the final regulatory text simply requires 
that the headlighting system must operate in manual mode in the event 
of such a malfunction.
    In response to Zoox's comment regarding editorial changes to 
S9.4.1.3, S9.4.1.6.1, and S.9.4.1.6.2, the agency does not believe 
these provisions are duplicative. The longstanding requirements for 
semiautomatic beam switching devices at S9.4.1.3 requires that a 
failure of the automatic control portion of the device must not result 
in the loss of manual operation and control of both upper and lower 
beams; neither S9.4.1.6.1 nor S9.4.1.6.2 clearly requires this. The 
final rule also does not adopt Zoox's suggested edits regarding fully 
autonomous vehicles. The appropriate fail-safe requirements in the 
event that a fully automatic (with no manual controls) ADB system fails 
raises a variety of issues that are outside the scope of this 
rulemaking.
    NHTSA agrees that upper beams may cause backscatter under certain 
weather conditions but does not believe this merits regulatory 
requirements for dealing with backscatter. The agency encourages 
manufacturers to provide, as part of the required operating 
instructions, information or instructions to the vehicle operator 
explaining the conditions in which an upper beam or an adaptive beam 
may or may not be optimal or appropriate.

[[Page 9992]]

G. Accommodation of Different Technologies

    In the NPRM, we explained that our intent was to ensure that ADB 
systems operate robustly, while not unduly restricting manufacturer 
design flexibility.
Comments
    NHTSA received a variety of comments regarding the appropriateness 
of the requirements for high-resolution ADB systems. Infineon commented 
that the final rule must allow for innovation (e.g., high-resolution 
systems). Texas Instruments also highlighted the existence of high-
resolution pixelated ADB systems that make it possible to design more 
flexible and precise beam patterns. It commented that the final rule 
should exempt high-resolution ADB systems from the requirement that the 
upper beam minima be met in areas of unreduced intensity and suggested 
allowing variable light levels between the lower beam minima and the 
upper beam maxima. It also asserted that the final rule should exempt 
high-resolution systems from the 25-mph minimum activation speed 
requirement to avoid blocking innovative uses of high-resolution 
lighting in urban settings. Texas Instruments also commented that the 
proposal did not consider advanced functions other than ADB (such as 
symbol generation) and requested that NHTSA consider including guidance 
in the regulations on how such systems could be deployed, possibly by 
considering them supplemental lighting. Volkswagen requested that NHTSA 
reconsider its past interpretation of the lower beam headlamp 
requirements as applied to LEDs (namely, that an integral beam headlamp 
that uses multiple LEDs would be compliant as long as the LEDs were 
designed to operate or fail as though they are wired in series) to 
accommodate high-definition ADB systems.
    Zoox commented that the final rule should permit highly-automated 
vehicles, those without manual controls for human drivers, to certify 
to the ADB requirements. Zoox also suggested deleting or modifying (by 
replacing ``must'' with ``may'') the operating instructions requirement 
in S9.4.1.1 to accommodate highly automated vehicles.
    Honda stated that manufacturers may employ multiple methods to 
produce an ADB beam, such as an enhanced lower beam, an enhanced upper 
beam, or a separate mid beam (essentially a partial upper beam in 
addition to a lower beam). Honda requested clarification on how NHTSA 
would interpret such ADB variations, and how this may impact technology 
innovation in this area. Honda also stated that opportunities exist to 
provide lighting patterns that are physically directed above lower beam 
levels and below higher beam levels. The goal of such a mid-beam 
lighting pattern would be to further balance the needs of visibility 
and glare prevention and expand potential ADB operation speeds and 
environments. They noted that since such a mid-beam would not solely be 
able to comply with the existing lower beam requirements, this mid beam 
would still require the lower beam to be activated. Honda requested 
clarification on how NHTSA would interpret the standard with respect to 
this.
Agency response
    NHTSA believes the final rule is generally technology neutral, and 
accommodates high-resolution technologies, provided they meet the 
rule's performance criteria. The agency disagrees with Texas 
Instruments' comment that the final rule should exempt high-resolution 
systems from certain requirements because the final rule is intended to 
be performance-based and technology neutral.
    However, as explained earlier, we have modified the proposal in 
response to the comments to provide more flexibility in beam design. 
The final rule does not limit the number or shape of areas of reduced 
or unreduced intensity, and permits localized dimming of the beam 
within the photometric limits of the region of the beam in which it is 
located (e.g., an area of reduced intensity may vary in intensity based 
on the surrounding environment provided that intensity stays within the 
corresponding maximum and minimum limits for the lower beam applicable 
to the direction of light). The final rule also provides for a 
transition zone. While the rule specifies the upper beam minima in the 
area of unreduced intensity, the definitions of the areas of reduced 
and unreduced intensity have been revised to give manufacturers more 
flexibility in beam design.\206\ The minimum activation speed has also 
been lowered to provide more flexibility to manufacturers.\207\
---------------------------------------------------------------------------

    \206\ See Section VIII.D, Laboratory (Component-Level) Testing.
    \207\ See Section VIII.E, Minimum Activation Speed.
---------------------------------------------------------------------------

    We are not revising the rule in response to the comments by Texas 
Instruments and Zoox regarding advanced functions such as on-road 
symbols and highly autonomous vehicles because those issues are outside 
the scope of this rulemaking. Volkswagen's comment regarding NHTSA's 
interpretation of the requirements with respect to LED failures applies 
to LED headlamps generally, not just ADB systems, and is also outside 
the scope of this rulemaking.
    With respect to Honda's comments, the final rule has two sets of 
requirements for an adaptive driving beam: The laboratory requirements 
and the track test requirements. Any ``mid-beam'' patterns would be 
tested according to these requirements and test procedures. For 
example, if Honda wishes to provide greater intensities than 1,400 at 
the 1.5 U line as required for a lower beam, but less than the 5,000 cd 
that is required at the upper beam test point 1U, 3R, the requirements 
finalized today would prohibit this (unless if it were within a 
transition zone, which may not exceed 1.0 degree in either the 
horizontal or vertical direction). As explained previously, this 
assures drivers that both glare protection and visibility of an ADB 
lighting system will be equivalent to that of an upper and lower beam. 
The reduced and unreduced intensity areas only need to meet the lower 
and upper beam requirements, not the levels of intensity provided by 
actual upper and lower beams installed on the vehicle. In the example 
above, if that point is an area of unreduced intensity, 5,000 cd is all 
that is required at 1U, 3R, even though many upper beams produce more 
than 30,000 cd in that area. In this way, aspects of a middle beam are 
permitted. For instance, if the upper beam installed on the vehicle 
produces high levels of reflected light from a sign in the 1U, 3R 
region, but a shaded area meeting the lower beam requirements are more 
limiting than desired because, the upper beam may be reduced to as 
little as 5,000 cd. The agency believes this provides flexibility to 
customize a headlighting system to achieve the performance described by 
Honda.
    Accordingly, the final rule does not adopt Honda's suggested edits 
of the NPRM's regulatory text. Nor does the rule adopt its suggestion 
that the lower beam (or area of reduced intensity) need only comply 
with the maximum photometric requirements of Table XIX \208\; as 
explained earlier in this document (Section VIII.D, Laboratory 
(Component-Level) Testing), the final rule retains the Table XIX 
requirements (both minima and maxima) for areas of

[[Page 9993]]

reduced intensity (and does not alter the lower beam requirements). 
However, the final rule does modify the regulatory text to clarify 
which photometry requirements apply to areas of reduced and unreduced 
intensities--for example, for an area of reduced intensity, the Table 
XIX test points that correspond (with respect to angular location) to 
that area of reduced intensity apply.
---------------------------------------------------------------------------

    \208\ Honda's comment referred to ``Table XVIII'', but since 
these are the upper beam requirements, and Honda's edit concerned 
the lower beam, we assume Honda meant to refer to Table XIX, which 
contains the lower beam photometric requirements.
---------------------------------------------------------------------------

H. Requirements for Semiautomatic Beam Switching Devices Other Than ADB 
and Applicability of Compliance Options

    The proposal retained the existing semiautomatic beam switching 
requirements for standard systems (i.e., beam switching devices that 
switch only between an upper beam and a single lower beam), explaining 
that these requirements have been in the standard for several decades, 
and while they might be updated, the focus of the rulemaking was on 
amending the standard to allow the adoption of ADB systems. The 
proposal classified these requirements as compliance Option 1, and the 
requirements for ADB systems as compliance Option 2.
Comments
    Valeo commented that ADB is essentially an advanced type of 
semiautomatic headlamp beam switching device and suggested that it 
could be certified to the existing requirements for these devices 
(classified under Option 1 in the proposal), without any of the 
proposed restrictions and vehicle level testing. Conversely, Global 
commented that a standard semiautomatic beam switching feature should 
be permitted to certify to the new ADB requirements (Option 2).
    Bosch and Volkswagen requested that NHTSA update the semiautomatic 
beam switching device requirements for conventional automatic ``hi-
beam'' systems (Option 1) to harmonize with SAE J656 (FEB 2010). Bosch 
commented that the current semiautomatic beam switching requirements 
(in S9.4.1 and 14.9.3.11 of the standard) are based on a 1969 SAE 
standard (SAE J565), and beam switching technology has evolved 
considerably since then. Bosch urged NHTSA to issue a supplemental 
notice of proposed rulemaking or a separate rulemaking proceeding to 
update the requirements to account for such advancements, including the 
use of camera-based systems and advanced light sources. Volkswagen 
pointed out that SAE J565 allows for a system without sensitivity 
adjustment, which modern camera-based systems no longer use, and 
modernized the luminous intensity minimum and maximum value 
requirements.
Agency Response
    The NPRM did not discuss, and, other than Valeo's comment, the 
commenters did not raise, the issue of whether an ADB system could be 
certified to the first option. NHTSA agrees that an ADB system is a 
type of semiautomatic beam switching device, but not necessarily that 
ADB systems were allowed by the standard prior to today's amendments. 
As explained in the NPRM, NHTSA's understanding has been that most, if 
not all, ADB systems would not have complied with at least some of the 
requirements that apply to semiautomatic beam switching devices. Among 
other things, most ADB systems would not comply with the semiautomatic 
beam switching device requirements that existed prior to today's rule 
(and are now classified as compliance Option 1) because they would not 
always comply with the existing photometry requirements. Accordingly, 
NHTSA expects that ADB systems will be certified to Option 2 and not 
Option 1.
    The NPRM also did not address whether standard semiautomatic beam 
switching systems could be certified to Option 2. The proposed 
regulatory text (along with the preamble) implied that semiautomatic 
headlamp beam switching devices other than ADB systems could only be 
certified to Option 1 and that ADB systems could only be certified to 
Option 2. In light of the fact that the proposal did not squarely raise 
this issue, and the fact that this approach maintains the status quo 
with respect to conventional semiautomatic beam switching devices, the 
final rule retains the proposed labels for the two compliance options. 
The final regulatory text provides that standard semiautomatic beam 
switching systems may only be certified to Option 1.
    As Bosch suggested in its comment, updating the Option 1 
semiautomatic beam switching requirements to account for advances in 
technology is outside the scope of this rulemaking. NHTSA will consider 
this idea as a suggestion for future rulemaking.

I. Physical Test Requirements

    The NPRM explained that FMVSS No. 108 sets forth a variety of 
performance requirements for semiautomatic beam switching devices (in 
S14.9.3.11), including a series of physical tests (e.g., vibration 
requirements). The NPRM did not propose to subject the switch 
controlling the ADB system to any physical test requirements, 
explaining that the existing physical test requirements date from the 
1960s and do not appear to extend usefully to modern ADB technologies. 
The NPRM also did not propose any new physical test requirements, based 
upon a tentative belief that market forces would ensure an ADB system's 
switching device will operate robustly. The proposal explained, 
however, that other FMVSS No. 108 headlamp requirements would apply to 
ADB systems, including the physical test requirements in S14.6 (e.g., 
an abrasion test and a chemical resistance test).
Comments
    Global concurred that new physical test requirements were 
unnecessary. Intertek agreed that ADB systems should be subject to all 
existing physical test requirements for current headlamps.
Agency Response
    The final rule follows the proposal and does not contain any 
physical tests specific to ADB systems. ADB systems will be subject to 
the physical test requirements applicable to all headlamp systems.

J. Other Requirements

Comments
    A few commenters mentioned unique challenges presented by the 
requirements for vertical headlamp arrangement for vehicles with high-
mounted headlamps. The Alliance and Ford commented that glare increases 
as vehicle mounting heights increase and stated that this may result in 
light trucks, utility and crossover vehicles not meeting NHTSA's glare 
requirements. They asserted that this fact could either exclude a 
significant portion of the new vehicle population from utilizing ADB 
technology or increase vehicle cost and complexity by necessitating 
additional hardware and components. To address this, they requested 
making the vertical beam arrangement requirement in S6.1.3.5.1 
optional. Toyota similarly stated that vehicles with headlamps mounted 
higher than the height from which glare limits were derived (0.62 m) 
would have difficulty meeting the proposed glare limits and could 
prevent introduction of ADB on a significant number of trucks and SUVs. 
Toyota stated that the 0.62 m height is based on the typical height of 
a passenger vehicle, which is not representative of the current vehicle 
fleet. Toyota stated that the shift in the fleet mix from the time this 
limit was derived makes it difficult for OEMs to meet the requirements 
at nominal or zero aim for these high-volume vehicles. Toyota suggested 
that

[[Page 9994]]

the design would have to aim the lower beams downward on higher-mounted 
headlamps in order to meet the glare limits for ADB, thereby 
deteriorating the lower beam visibility provided to the driver. Toyota 
claimed that this would reduce the safety benefits of ADB by either 
sacrificing optimal lower beam performance or limiting the introduction 
of ADB on a significant number of vehicles.
    Related to this, Subaru commented specifically on the proposed 
requirements for headlamp arrangement,\209\ stating that it seemed to 
imply that a vehicle without parking lamps might somehow be permitted 
by the rule. They requested that NHTSA clarify this provision and asked 
whether it would simply mean a vehicle must illuminate the outermost 
lamps when the ADB system is active.
---------------------------------------------------------------------------

    \209\ See S9.4.1.6.8 in the proposed regulatory text. (``When 
the ADB system is activated, the lower beam may be provided by any 
combination of headlamps or light sources, provided there is a 
parking lamp. If parking lamps meeting the requirements of this 
standard are not installed, the ADB system may be provided using any 
combination of headlamps but must include the outermost installed 
headlamps to show the overall width of the vehicle.'') The NPRM 
considered the adaptive driving beam to be a lower beam. As 
explained earlier, under the final rule the adaptive driving beam is 
defined as a new beam type and is accordingly not considered a lower 
beam.
---------------------------------------------------------------------------

Agency Response
    With respect to the comments about vehicles with high-mounted 
headlamps, this issue is also present with respect to the lower beams 
on those vehicles. As such, those vehicles already tend to have their 
headlamps aimed downward, to avoid glaring oncoming or preceding 
vehicles. While manufacturers might feel the need to aim the headlamps 
somewhat lower to accommodate an adaptive driving beam, that would be 
likely to have the greatest impact on areas of reduced intensity, not 
areas of unreduced intensity (due to the characteristics of lower beam 
and upper beam patterns), and would not likely have an outsized impact 
on visibility.
    Additionally, as suggested by the Alliance and Ford, manufacturers 
might wish to alter the vertical arrangement of the headlamps and/or 
light sources. However, the commenters who commented about high-mounted 
headlamps appeared to overlook that the proposed rule permitted (in 
S9.4.1.6.8) the adaptive driving beam to be provided by any combination 
of headlamps. In light of the comments, the final rule retains the 
proposed provision (now codified at S9.4.1.6.5) but modifies and 
clarifies the regulatory text to reflect that the adaptive driving beam 
is now considered a new beam type and not a lower beam as was initially 
proposed.
    Regarding Subaru's comment, the proposed S9.4.1.6.8 was not 
intended to imply that parking lamp requirements were being eliminated. 
The standard requires parking lamps on all passenger cars, and MPVs, 
trucks, and buses less than 2032 mm in overall width. Today's final 
rule does not alter this requirement. On vehicles for which parking 
lamps are not required, the final rule requires that the adaptive 
driving beam may be provided using any combination of headlamps but 
must include the outermost installed headlamps to show the overall 
width of the vehicle.
    The final rule amends 10.14.1, 10.15.1 and 10.16.1 to require that 
a headlamp system provide not more than two adaptive driving beams; 
this parallels the same requirement for upper beams and lower beams. 
The final rule does not amend 10.13.1 because ADB does not appear 
feasible for sealed beam systems.

K. Information Reporting

    The NPRM did not propose any reporting requirements related to ADB 
system performance in the field.
Comment
    Consumer Reports commented that NHTSA should require manufacturers 
to submit detailed and timely information regarding the performance of 
ADB systems and the consumer experience with them as they are 
introduced. They suggested that this information be made available in 
aggregate form publicly, at a minimum, and include crash reduction 
estimates, near-miss statistics that are reasonably related to 
lighting, and consumer satisfaction data, including documentation of 
the technology's impact on glare experienced by other drivers.
Agency Response
    NHTSA is not adopting the information collection requirement 
suggested by Consumer Reports. If, after ADB systems have been 
deployed, the agency sees a need to obtain detailed information on the 
performance of ADB systems, it will address the matter at that time.

L. Aftermarket Compliance

    Motor vehicle manufacturers are required to certify that their 
vehicles comply with all applicable FMVSS, including FMVSS No. 
108.\210\ FMVSS No. 108 also applies to replacement equipment (i.e., 
equipment sold on the aftermarket to replace original equipment 
installed on the vehicle).\211\ 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 be capable of 
replacing.\212\ Each replacement lamp 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 device is 
installed on the vehicle.\213\ A manufacturer of replacement equipment 
is responsible for certifying that equipment.\214\
---------------------------------------------------------------------------

    \210\ 49 U.S.C. 30115.
    \211\ 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.'').
    \212\ S6.7.1.1.
    \213\ S6.7.1.2.
    \214\ 49 U.S.C. 30115; Letter from NHTSA to George Van Straten, 
Van Straten Heated Tail Light Co., Inc. (Aug. 11, 1989).
---------------------------------------------------------------------------

    The NPRM stated that 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, and sought comment on this.
Comments
    TSEI requested clarification of whether the rule permits 
aftermarket ADB systems and stated that the benefits of ADB systems 
would be the same for aftermarket systems as for original equipment. 
Intertek supported allowing aftermarket parts, and believed that it is 
entirely feasible in aftermarket certification to rent or purchase the 
vehicle for which the ADB headlamp or switch is designed in order to 
conduct vehicle-level testing, and that while technical challenges 
could make aftermarket systems/parts cost-prohibitive, that will be 
driven by market demand.
Agency Response
    The final rule permits certification of aftermarket ADB systems and 
parts. There would seem to be essentially two categories of aftermarket 
ADB systems. The first is an aftermarket ADB system replacing an 
original-equipment system; the second is an aftermarket ADB system 
replacing a non-ADB headlamp. In either case, the aftermarket ADB 
headlamp would be a ``replacement'' headlamp subject to FMVSS No. 108 
because it would be ``replacing like equipment on vehicles to which the 
standard applies.'' \215\ As such, the

[[Page 9995]]

aftermarket manufacturer will need to certify the headlamp to FMVSS No. 
108; that is, the headlamp ``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.'' This would include the ADB 
requirements, as well as any other applicable requirements. 
Accordingly, an aftermarket manufacturer could certify and sell ADB 
headlamps, if the product complies and the manufacturer was able to 
make a good-faith certification.\216\
---------------------------------------------------------------------------

    \215\ S3.3.
    \216\ See also 70 FR 65972, 65974 (Nov. 1, 2005) (Notice of 
Interpretation) (``To the extent the vehicle manufacturer could have 
certified the vehicle using the replacement lamp, instead of the 
lamp it actually used, we believe the replacement lamp should be 
viewed as being designed to conform to FMVSS No. 108.'')
---------------------------------------------------------------------------

    As noted in the NPRM, it might be difficult as a practical matter 
for aftermarket manufacturers to make the necessary certification. For 
example, if an aftermarket supplier wanted to develop an ADB system for 
a vehicle not originally equipped with ADB, it would need to certify 
that the aftermarket ADB system was designed to conform with this final 
rule and that it would not otherwise take the vehicle out of compliance 
with any other standards. Because the final rule requires specific 
switching conditions, the aftermarket system may need to replace the 
interior lighting control systems to allow for control of the ADB 
system. On the other hand, the final rule significantly simplifies the 
test procedures the agency will use to determine compliance, which 
could ease the certification of aftermarket systems.

M. Exemption Petitions

    In 2016, Volkswagen submitted a petition for a temporary exemption 
(under 49 CFR part 555) from some of the requirements of FMVSS No. 108 
to sell up to 2,500 exempted vehicles equipped with ADB systems during 
each of the 12-month periods covered by the requested exemption. NHTSA 
published a notice of receipt of this petition on September 11, 2017 
and provided a 30-day comment period.\217\ BMW of North America, LLC 
(BMW) submitted a similar petition, dated October 27, 2017. On March 
22, 2018, NHTSA published a notice of receipt of the BMW petition and 
requested additional information from both petitioners.\218\ Both 
Volkswagen and BMW subsequently submitted additional information to the 
docket. Prior to today, NHTSA had not made a decision on either 
petition.
---------------------------------------------------------------------------

    \217\ 82 FR 42720 (Docket No. NHTSA-2017-0018).
    \218\ 83 FR 12650 (Docket No. NHTSA-2017-0018).
---------------------------------------------------------------------------

Comments
    The Alliance, Volkswagen, and Auto Innovators requested NHTSA grant 
these petitions to facilitate gathering of usage and performance data.
Agency Response
    NHTSA believes that the publication of this final rule obviates the 
need for the requested exemptions. NHTSA is today publishing a separate 
notice of decision denying the petitions (Docket No. NHTSA-2017-0018).

N. Compliance Date

    This final rule is effective on the date of publication in the 
Federal Register. The Alliance requested that the final rule be 
effective on publication. This final rule permits the certification of 
vehicles equipped with ADB systems if a manufacturer chooses to equip a 
vehicle with such a system. NHTSA believes there is good cause to 
permit ADB systems meeting FMVSS No. 108 quickly as possible because 
the systems produce increased illumination without increasing glare, 
and have the potential to offer significant safety benefits in avoiding 
collisions with pedestrians, cyclists, and roadside objects. Good cause 
exists for these amendments to be made effective immediately pursuant 
to 49 U.S.C. 30111(d), which allows an FMVSS to become effective sooner 
than 180 days after publication of the standard if an earlier effective 
date is in the public interest.

O. Regulatory Alternatives

    In developing the final rule, NHTSA considered the ECE ADB 
requirements and SAE J3069. As explained earlier, the ECE requirements 
are not sufficiently objective to be incorporated into an FMVSS. 
Accordingly, the main regulatory alternative NHTSA considered was SAE 
J3069.
    The proposal deviated from SAE J3069 in several ways; the NPRM 
explained this in detail. In general, we explained that there were two 
major differences.
    First, the proposed vehicle-level track test was more realistic and 
complex than the SAE J3069 track test. SAE J3069 specifies testing 
using a straight-path scenario (and simulating curves with fixture 
placement), and instead of using oncoming or preceding stimulus 
vehicles, uses stationary test fixtures positioned at specified 
locations adjacent to the test track. The proposed test permitted NHTSA 
to test using scenarios having curved paths (with various radii of 
curvature) using a broad range of FMVSS-certified vehicles as oncoming 
or preceding vehicles.
    Second, the proposal specified additional component-level 
photometric requirements to regulate both glare and visibility that 
were not included in the SAE document. We proposed to require that an 
area of reduced intensity be designed to conform to the Table XIX lower 
beam photometry requirements (both maxima and minima). This differed 
from SAE J3069, which only specified the lower beam maxima for the area 
of reduced intensity. We similarly proposed that an area of unreduced 
intensity conform with the Table XVIII upper beam photometric maxima 
and minima. SAE J3069 required only that the lower beam minima be met 
in this area.
    NHTSA tentatively concluded that the differences between the 
proposal and SAE J3069 were needed to ensure the ADB systems meet the 
dual safety needs of glare prevention and visibility.
Comments
    Many commenters asserted that NHTSA should adopt either SAE J3069 
or the ECE requirements. Concerns about the proposal not harmonizing 
with either the SAE or ECE requirements were mainly focused on the 
broad acceptance of existing systems in the world market and the 
additional costs associated with development of systems that would 
comply with the proposal. No data were presented to quantify any 
additional development or system costs to comply with the proposed 
rule.
    As noted at various points earlier in this document, a few 
commenters did support a variety of specific departures from SAE J3069. 
More generally, Intertek agreed that the SAE J3069 approach may not be 
sufficient to validate ADB performance over the full range of typical 
real-world situations; it supported a more rigorous track test than 
specified in SAE J3069, but also believed that the full set of proposed 
test scenarios might not be necessary.
    Many commenters, however, strongly supported harmonization with SAE 
J3069 and/or the ECE requirements in order to align with requirements 
or approaches in other markets. Honda, Global, GM, SAE, CEI, Toyota, 
the Alliance, Mobileye, and OSRAM specifically supported SAE J3069. 
MEMA, Infineo, Valeo, and NAFA supported either SAE J3069 or the ECE 
requirements. Ford, Volkswagen, SMMT, Mobileye, OICA, NAFA, and Hella 
supported global harmonization generally, and Seastrunk and Montgomery 
supported harmonizing with the ECE requirements. Mobileye

[[Page 9996]]

supported making relatively minor changes to SAE J3069 (such as more 
realistic lamps). Commenters made a variety of arguments related to 
this.
    A number of commenters (Global, MEMA, EMA, Intertek, CEI, 
Volkswagen, SAE, Mobileye, the Alliance, Hella, OSRAM, SMMT, Ford, and 
OICA) commented or supported the comments of others that the proposed 
departures from the SAE and ECE standards would lead to additional 
costs, both because the different requirements would require different 
hardware, components, and/or software and because the proposed testing 
was more complex. Global also commented that the lower costs would come 
with no diminution in performance and an increase in visibility. SAE 
commented that SAE J3069 was designed to harmonize with the ECE 
requirements in order to allow common headlamps, controllers, and 
sensors across markets; any aspects not harmonized could be 
accommodated in headlamp aim or software calibration differences to 
avoid hardware differences. OSRAM, SMMT, Volkswagen, Ford, MEMA, and 
OICA agreed with or echoed SAE's comment. Hella commented that the NPRM 
will demand completely different headlamp systems and additionally 
different forward sensor designs compared to those already in use. This 
means, that additional development is needed to establish an ADB system 
in the US when compared to the rest of the world. EMA added that its 
members have been developing ADB systems based on the ECE requirements 
and have no experience with the proposed requirements; moreover, heavy-
duty vehicles are often engaged in cross-border operation that makes 
harmonized requirements even more appropriate. Intertek estimated that 
that the proposed track testing could cost as much as two to four times 
more than testing to the SAE standard, which itself is around three 
times costlier than current headlamp testing.
    Several commenters (MEMA, the Alliance, Ford, Volkswagen, OICA, 
Hella, GM, SAE, CEI, and SMMT) stated that the proposal would 
disharmonize with Canada. MEMA noted that the Canadian regulations 
accept either ECE R123 or SAE J3069, and stated that the proposal was 
inconsistent with a Memorandum of Understanding between the U.S. and 
Canada regarding regulatory cooperation.\219\ The Alliance commented 
that while there have been longstanding differences with headlighting 
requirements between the U.S. and Europe, differences between the U.S. 
and Canada have been minimal. Ford commented that harmonization makes 
sense given the close integration of the two markets.
---------------------------------------------------------------------------

    \219\ The comment cited the Memorandum of Understanding Between 
the Treasury Board of Canada Secretariat and OIRA Regarding the 
Canada[hyphen]United States Regulatory Cooperation Council, June 4, 
2018.
---------------------------------------------------------------------------

    Infineon, EMA, Volkswagen, the Alliance, CEI, and NAFA commented 
that the increased costs associated with the proposal would increase 
the cost to consumers, hindering ADB adoption and the accompanying 
safety benefits. CEI also contended that reduced consumer demand for 
ADB systems could also reduce manufacturer investment in lighting 
system research and development. NAFA highlighted the potential impact 
on adoption by vehicle fleets for which cost is important.
    Global, Volkswagen, and the Alliance suggested that the 
disharmonized aspects of the proposal would not lead to safety benefits 
or could decrease safety benefits. For example, Volkswagen stated that, 
compared to the proposal, SAE J3069 would lead to ADB systems providing 
better visibility. Volkswagen also stated that there is no evidence 
that the ECE requirements are leading to excessive glare, and that it 
has developed numerous ADB systems for other markets and tested to the 
SAE standard, and has not received any complaints from customers or 
regulatory authorities about glare. A few commenters (GM, Toyota, MEMA, 
Global, Volkswagen) also stated that J3069 would provide a more 
objective, practicable, and/or repeatable test procedure.
Agency Response
    NHTSA agrees with the commenters that harmonization is an important 
goal. Moreover, the National Technology Transfer and Advancement Act 
directs Federal agencies to use voluntary consensus standards in lieu 
of government-unique standards.\220\ This directive, however, is not 
absolute. The NTTAA goes on to provide that an agency may decline to 
use existing consensus standards if it determines that such standards 
are inconsistent with applicable law or otherwise impractical.\221\ 
``Impractical'' includes circumstances in which the use of consensus 
standards would fail to serve the agency's regulatory needs; be 
inconsistent with a provision of law; or be less useful than the use of 
another standard.\222\
---------------------------------------------------------------------------

    \220\ National Technology Transfer and Advancement Act of 1995, 
Public Law 104-113, 12(d)(1), 110 Stat. 775 (1996).
    \221\ Id. at Sec.  12(d)(3).
    \222\ Office of Management and Budget, Circular No. A-119, ] 
5(c)(ii), Federal Participation in the Development and Use of 
Voluntary Consensus Standards and in Conformity Assessment 
Activities (Jan. 26, 2016).
---------------------------------------------------------------------------

    In light of these requirements, as well as the requirements of 49 
U.S.C. 30111, and in response to the comments, NHTSA has modified the 
proposal to more closely follow SAE J3069 where warranted, but to 
deviate from that standard where necessary. The most important of these 
changes were specifying stationary stimulus test fixtures instead of 
dynamic stimulus vehicles and substantially simplifying the number and 
complexity of the test scenarios. However, there are several aspects of 
the final rule for which NHTSA ultimately concluded that deviation from 
SAE J3069 is warranted because J3069 did not adequately address glare 
or visibility. The major differences are summarized in Table 12. The 
preceding sections of this document discuss in detail the ways in which 
the final rule follows and differs from SAE J3069, and explains why we 
believe these departures are justified.

  Table 15--Summary of Major Differences Between the Final Rule and SAE
                                  J3069
------------------------------------------------------------------------
          Test elements               Final rule           SAE J3069
------------------------------------------------------------------------
Track test:
    Glare limit applicability...  Applies the glare   Applies the glare
                                   limits throughout   limits only at 30
                                   the measurement     m, 60 m, 120 m,
                                   range specified     and 155 m.
                                   for each scenario.
    Fixture lighting............  Specifies actual    Specifies lamp
                                   vehicle lamp..      assemblies
                                                       intended to
                                                       simulate vehicle
                                                       lamps.
    Test track geometry.........  Specifies actual    Specifies a
                                   curves of various   straight path and
                                   sizes.              uses fixture
                                                       placement to
                                                       simulate curves.

[[Page 9997]]

 
    Compliance criteria.........  Specifies           Allows measured
                                   allowances for      illuminance to
                                   momentary glare     exceed an
                                   and vehicle pitch   applicable glare
                                   fluctuations.       limit if it does
                                                       not exceed 125%
                                                       of the lower beam
                                                       illuminance under
                                                       the same
                                                       conditions.
    Specifications related to     Specifies vehicle   Recommends the
     smoothness of road surface.   pitch allowance.    test track have
                                                       an International
                                                       Roughness Index
                                                       of less than 1.5
                                                       m/km.
Laboratory Test:
    Area of reduced intensity...  Specifies lower     Specifies lower
                                   beam (Table XIX)    beam maxima.
                                   minima and maxima.
    Area of unreduced intensity.  Specifies upper     Specifies lower
                                   beam (Table         beam minima.
                                   XVIII) minima and
                                   maxima.
Physical tests..................  Not specified.....  Specifies various
                                                       physical tests.
Minimum activation speed........  20 mph............  Not specified.
------------------------------------------------------------------------

    NHTSA recognizes that the final rule is more demanding than SAE 
J3069 in several respects, and further recognizes that this will result 
in some additional costs to develop and test these systems. The agency 
believes these additional costs are justified because the departures 
from the SAE test methods are warranted to properly address either 
glare or visibility concerns. NHTSA is not persuaded that the test 
procedures represent a significant cost burden over testing ADB systems 
per the SAE J3069 test. Much of the development work the industry has 
conducted on ADB systems for use in markets that permit certification 
to the UNECE or SAE standards would directly apply to the performance 
tests finalized today. As explained throughout this document, NHTSA has 
adopted parameters similar to either the SAE standard or the UNECE 
standard where appropriate.
    For these same reasons, the agency believes that the resulting 
disharmonization will not hinder ADB deployment. Similarly, NHTSA 
concludes that the disharmonization with Canada is justified, and is 
not inconsistent with the Memorandum of Understanding, which provides, 
among other things, that the countries' respective regulations continue 
to apply, and that closer alignment of regulations would be consistent 
with their respective national laws and policies.
    NHTSA also concludes the final rule is practicable. As explained in 
previous sections in the preamble, ADB systems performed the same on 
many of the final rule scenarios and the most closely analogous SAE 
scenarios. As also explained above, there are likely certain test 
scenarios (for example, right direction curves) with which some current 
ADB systems may not comply; however, in these instances NHTSA believes 
that manufacturers should be able to modify existing systems to meet 
the requirements.
    NHTSA has also concluded that the final rule is objective and 
repeatable. The final rule sets out a rational test procedure that 
yields a clear answer based upon readings obtained from measuring 
instruments and is capable of producing identical results when test 
conditions are exactly duplicated.\223\ Further, the final rule 
establishes the specific scenarios the agency may test, including 
ranges and values for key testing parameters, and specific numeric 
limits for the maximum allowable illuminance at certain distances. 
NHTSA believes that the final rule specifies the test parameters that 
contribute to most of the test-related variability, and that there is 
no ambiguity with respect to the parameter values (e.g., differing 
radii of curvature) NHTSA may select in compliance testing. To further 
evaluate the repeatability of the track test, NHTSA conducted a 
repeatability analysis, which shows that the test is repeatable (see 
Section VIII.C.11, Repeatability).
---------------------------------------------------------------------------

    \223\ See Chrysler Corp. v. Dept. of Transp., 472 F.2d 659, 676 
(6th Cir. 1972) (construing ``objective'').
---------------------------------------------------------------------------

P. Overview of Benefits and Costs

    The NPRM considered 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).\224\ Based on this qualitative analysis, NHTSA tentatively 
concluded that ADB systems should be permitted (because the proposal 
would lead to higher net benefits compared to the status quo in which 
ADB systems are not deployed) and that the proposed requirements and 
test procedures would lead to higher net benefits than SAE J3069.\225\
---------------------------------------------------------------------------

    \224\ NHTSA has not quantified the costs and benefits of the 
proposal for the reasons discussed in the NPRM and below in Section 
X, Rulemaking Analyses and Notices (in connection with the 
discussion of Executive Order 12866).
    \225\ For additional information, see the NPRM, pp. 51799-51801.
---------------------------------------------------------------------------

Comments
    With regard to allowing the introduction of ADB systems, as noted 
earlier, all the industry and public-interest commenters supported 
amending the standard to allow the introduction of ADB technology. Many 
of the drive-in theatre owner/operators indicated some level of support 
for the rule (assuming it provides for manual control). The majority of 
comments from individual members of the public supported the proposal, 
frequently on the grounds that it would likely reduce glare or increase 
safety. Some individual commenters, and some owner/operators of drive-
in movie theatres, opposed the proposal and/or expressed concern that 
the introduction of ADB systems could lead to increased glare.
    With respect to the proposed requirements and test procedures, most 
industry commenters stated that the proposed requirements were too 
stringent, and did not meet the need for safety because they 
overemphasized glare prevention at the expense of visibility. \226\ 
Several commenters (Mobileye, the Alliance, IIHS, Auto Innovators, 
Toyota, Volkswagen) contended that the proposal did not maximize 
overall benefits because it prioritized glare prevention over enhanced 
visibility and stated that the final rule should instead place greater 
weight on the benefits from enhanced visibility. For example, Mobileye 
commented that the proposal would not allow OEMs to tune an ADB system 
to

[[Page 9998]]

provide optimal visibility to drivers. Mobileye contended that the 
result would be that the benefit of providing a driver with higher 
visibility will be diminished with negligible gain in preventing glare. 
IIHS also argued that, in terms of safety, the glare problem appears 
relatively small (glare was cited in only 1% of non-daylight crashes in 
the National Motor Vehicle Crash Causation Survey). Auto Innovators 
similarly commented that NHTSA's own research indicates that it is 
difficult to determine glare as a direct cause of crashes or 
fatalities.\227\ Auto Innovators noted that NHTSA's own research has 
shown that while glare was a contributing factor in only about 0.3% of 
nighttime fatal crashes \228\ over 70% of pedestrian fatalities occur 
at night.\229\ Auto Innovators also pointed to IIHS research finding 
that between 2009 and 2016, pedestrian deaths in dark conditions 
increased 56%\230\ and a report from the Government Accountability 
Office finding that the number of pedestrians killed annually in motor 
vehicle crashes increased 43% between 2008 and 2018 and recommending 
NHTSA take additional actions to address pedestrian safety.\231\ Toyota 
also asserted that glare is predominantly an issue of inconvenience and 
discomfort, and that the proposal was not justified by data showing 
that glare is a safety concern that requires such stringency.
---------------------------------------------------------------------------

    \226\ There were numerous comments as to why specific aspects of 
the proposal were too stringent (for example, testing on small right 
curves). These specific comments are addressed in the preceding 
sections of the preamble. This section deals with more general 
comments about the overall stringency of the requirements and the 
relative benefits of visibility and glare prevention.
    \227\ Comment from Alliance for Automotive Innovation (NHTSA-
2018-0090-0219), p. 8 (citing Nighttime Glare and Driving 
Performance, Report to Congress, National Highway Traffic Safety 
Administration, Department of Transportation (2007)).
    \228\ Id. (citing National Highway Traffic Safety 
Administration. 2014. Traffic Safety Facts 2012 Data: Pedestrians, 
DOT HS 811 888. Washington, DC: National Highway Traffic Safety 
Administration.).
    \229\ Id. (citing National Highway Traffic Safety 
Administration. 2018 (Revised). Traffic Safety Facts 2016 Data: 
Pedestrians, DOT HS 812 493. Washington, DC: National Highway 
Traffic Safety Administration.).
    \230\ Id. (citing www.iihs.org/iihs/sr/statusreport/article/53/3/1.).
    \231\ Id., pp. 8-9 (citing Government Accountability Office. 
(2020, April). NHTSA Needs to Decide Whether to Include Pedestrian 
Safety Tests in Its New Car Assessment Program. (Publication No. 
GAO-20-419) (retrieved from www.gao.gov/assets/710/706348.pdf.).
---------------------------------------------------------------------------

    Similarly, many commenters contended that the proposal, 
particularly the track test, was costly, burdensome, and impracticable. 
See Section VIII.C.1, Practicability of Proposed Test Scenarios. Honda 
also stated more generally that the proposed dynamic track test 
procedure did not strike the appropriate balance between effectiveness 
and practicality. On the other hand, AAA recommended that the 
requirements be technology-forcing with respect to improvements in both 
glare prevention and visibility, and not simply adhere to established 
minimums because absent such requirements such improvement may not be 
made.
    A few commenters commented that the final rule would better balance 
visibility and glare if it exempted ADB systems from some or all the 
laboratory photometric requirements. In this context, IIHS specifically 
asserted that the Table XIX lower beam requirements should not apply to 
ADB, the Alliance suggested that none of the laboratory requirements 
should apply to ADB, and Volkswagen stated that the upper beam maximum 
should not apply.
    Mobileye and the Alliance argued that the proposal's emphasis on 
glare was also unnecessary because market forces would sufficiently 
incentivize glare prevention. Mobileye explained that OEMs are more 
likely to hear from owners of ADB-equipped vehicles about problems with 
glare than with visibility. The Alliance commented that manufacturers 
are concerned with customer safety and satisfaction; for example, 
automatic high beam systems are evaluated from both driver and other 
motorist perspectives via intracompany test drive scenarios, some of 
which include the presence of simulated ``other motorists.'' The 
Alliance asserted that the deployment of ADB systems will result in a 
decrease in the volume of glare complaints received by NHTSA.
    As noted in the regulatory alternatives section, many commenters 
recommended adopting SAE J3069. Some commenters (Global, Volkswagen, 
the Alliance) suggested that the disharmonized aspects of the proposal 
would not lead to safety benefits or could decrease safety benefits. 
Commenters also claimed that the proposal would be more costly than SAE 
J3069 and/or the ECE requirements because the disharmonization would 
result in additional development and component costs.
Agency Response
    With respect to the costs and benefits of the final rule compared 
to the current baseline in which ADB systems are not deployed, NHTSA 
has concluded that because the rulemaking expands the set of consumer 
choices (compared to the status quo), it is an enabling regulation. 
NHTSA also concludes that, because it expects positive benefits and 
cost savings,\232\ this final rule will lead to higher net benefits 
compared to the status quo in which ADB systems are not deployed.
---------------------------------------------------------------------------

    \232\ As we explained in the NPRM, the estimated cost savings of 
an enabling regulation include the full opportunity costs of the 
previously foregone activities (i.e., the sum of consumer and 
producer surplus, minus any fixed costs). NPRM at p. 51800.
---------------------------------------------------------------------------

    With respect to the costs and benefits of the proposal compared to 
SAE J3069, in the NPRM NHTSA tentatively concluded that although the 
proposal was likely more costly than SAE J3069 (due to higher 
compliance testing and equipment costs), these higher costs were likely 
outweighed by the higher safety-related benefits (and lower glare 
disbenefits). We therefore tentatively concluded that the likely net 
benefits of the proposal were greater than if we adopted SAE J3069 in 
every respect. As we explain below, however, after considering the 
comments NHTSA has concluded that more closely following SAE J3069 in 
certain respects would lead to higher net benefits than the proposal 
through lower costs (testing and equipment) and higher benefits 
(visibility) without meaningfully increasing disbenefits (glare). We 
believe the final rule appropriately balances benefits and costs and 
that the net benefits of the final rule are greater than if we adopted 
SAE J3069 in every respect.
    As an initial matter, NHTSA agrees with the commenters that it is 
difficult to precisely determine the risk from glare; that pedestrian 
fatalities are on the rise; and therefore that improved visibility 
could help to address this trend. Nevertheless, in the absence of 
empirical evidence to the contrary, the agency still believes that 
glare poses a non-trivial safety risk that justifies some departures 
from the SAE standard.
    NHTSA agrees with the commenters that the proposed track test to 
evaluate glare was too stringent in a couple of ways. First, the 
proposed track test somewhat overemphasized glare at the expense of 
visibility. This includes that lower beams that currently comply with 
FMVSS No. 108 may not have complied with some of the proposed 
scenarios. NHTSA also recognizes that the proposed requirements may 
have led manufacturers to tune ADB systems to be overly conservative in 
order to have acceptable compliance margins, potentially diminishing 
the visibility benefits that ADB can provide. Second, the agency agrees 
that the proposed track test procedure included redundant scenarios, 
and that the final rule can more closely follow SAE J3069 without 
sacrificing the evaluative power of the test.
    The modifications we have made to the proposal address those issues 
regarding stringency. The most important of the modifications are the 
reduced number of test scenarios and the specification of stationary 
test

[[Page 9999]]

fixtures instead of dynamic stimulus vehicles to follow SAE J3069 more 
closely and reduce the complexity of testing. However, the final track 
test procedure continues to depart from SAE J3069 in a few ways, 
especially in that it retains the use of curved test path scenarios and 
uses fixtures fitted with actual vehicle lamps. The agency believes 
that the final test scenarios are efficient yet sufficient to determine 
whether an ADB system prevents glare to other motorists, and that the 
final rule strikes an appropriate balance between visibility and glare 
prevention, and between safety and practicability. The reasons for the 
agency's specific choices are explained earlier in the preamble.
    NHTSA believes the final rule is neither cost-prohibitive nor 
impracticable compared to the alternatives. As explained in Section 
VIII.O (Regulatory Alternatives), design and development costs will not 
significantly differ from those that would have been incurred by 
compliance with the SAE or ECE standards. On the other hand, with 
respect to AAA's comment that the final rule be technology-forcing, 
NHTSA believes the final rule is somewhat technology forcing with 
respect to glare: While the requirements are generally within the 
capabilities of current ADB system, there are some respects in which 
tested ADB performance fell short (for example, appropriately 
responding to the motorcycle fixture). ADB systems may therefore need 
to be improved or modified to certify to some aspects of the 
requirements. With respect to visibility, the final rule does depart 
from SAE J3069 in requiring the lower beam minima in an area of reduced 
intensity and the upper beam minima in an area of unreduced intensity.
    With respect to the comments about market incentives to mitigate 
glare, NHTSA does not doubt that OEMs are attentive to owner concerns 
but believes that vehicle owners are less likely to notify OEMs about 
issues with glaring other motorists. Manufacturers pointed to the lack 
of warranty claims or vehicle owner complaints about glare issues (and 
Volkswagen noted that it has not received any owner complaints about 
ADB systems causing glare). Of course, this could indicate that there 
are no glare issues, but it also could indicate that glare issues go 
unreported. In any case, the fact that glare is largely an externality 
would seem to make glare mitigation less likely to be incentivized by 
market signals.
    NHTSA also believes that the final component-level laboratory 
testing requirements strike an appropriate balance between visibility 
and glare. In particular, the agency believes (and the comments did not 
convince us otherwise) that specifying the lower beam photometric 
minima for areas of reduced intensity and the upper beam minima in 
areas of unreduced intensity are important for guaranteeing a minimum 
level of visibility. Conversely, as discussed earlier in the preamble, 
it is important to specify the current upper beam maximum for areas of 
unreduced intensity.

IX. Appendix to FMVSS No. 108 (Table of Contents)

    When NHTSA re-wrote FMVSS No. 108 (the final rule for which was 
published in 2007), it added an appendix that contained a table of 
contents for the standard.\233\ The Office of the Federal Register no 
longer allows appendices to sections, and Sec.  571.108 is the only 
section in Part 571 to have a table of contents. Because the appendix 
may be a useful aid to users of the standard, rather than simply 
deleting the appendix NHTSA is moving it to the end of subpart B of 
Part 571.
---------------------------------------------------------------------------

    \233\ 72 FR 68234 (Dec. 4, 2007). This was an administrative 
rewrite; it did not impose any new substantive requirements on 
manufacturers.
---------------------------------------------------------------------------

X. Rulemaking Analyses and Notices

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

    We have considered the potential impact of this final rule under 
Executive Order 12866, Executive Order 13563, and DOT Order 2100.6A. 
This final rule is not significant and so was not reviewed by OMB under 
E.O. 12866 and is not of special note to the Department under DOT Order 
2100.6A. Pursuant to E.O. 12866 and the Department's policies, we have 
identified the problem this rule addresses, assessed the benefits and 
costs, and considered alternatives. These analyses have been provided 
in preceding sections of the preamble; benefits and costs are 
summarized in Section VIII.P. As explained below, NHTSA has determined 
that quantifying the benefits and costs is not practicable for this 
rulemaking.
    Quantifying the benefits of the rule--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 systems (as well as the potential penetration rate of ADB systems). 
For example, headlamp state (on-off, upper-lower beam) is not reflected 
in the data for many pedestrian crashes. Nevertheless, in the NPRM we 
attempted to broadly estimate the magnitude of the target 
population.\234\
---------------------------------------------------------------------------

    \234\ See Appendix A in the NPRM. Toyota's rulemaking petition 
also includes a target population analysis using a different 
methodology. Letter from Tom Stricker, Toyota Motor North America, 
Inc. to NHTSA, Appendix D (Mar. 29, 2013).
---------------------------------------------------------------------------

    Quantification of costs is similarly not practicable. The only 
currently-available ADB systems are in foreign markets such as Europe. 
We believe, as explained in the discussion of regulatory alternatives 
and elsewhere in the preamble, that an ECE-approved ADB system 
(modified to have FMVSS 108-compliant photometry) would, with some 
further modifications, be able to comply with the rule's requirements 
(see the discussion of regulatory alternatives). For the reasons 
explained in detail in the preamble, we believe that the final 
requirements are generally within the capabilities of existing ADB 
systems, although some adjustments might be necessary. We also note 
that this final rule does not require manufacturers to equip their 
vehicles with ADB systems. The requirements of this final rule specify 
minimum performance requirements for the lighting systems that only 
apply if manufacturers choose to equip vehicles with ADB systems.
    Although NHTSA has concluded that quantification of costs and 
benefits is not practicable, we have qualitatively assessed the 
benefits and costs of the final rule. As we explain in Section VIII.P, 
Overview of Benefits and Costs, we believe the final rule appropriately 
balances benefits and costs and that the net benefits of the final rule 
are greater compared to both the status quo in which ADB systems are 
not deployed and if we adopted SAE J3069 in every respect.

Executive Order 13609: Promoting International Regulatory Cooperation

    The policy statement in section 1 of Executive Order 13609 provides 
that the regulatory approaches taken by foreign governments may differ 
from those taken by the United States to address similar issues, and 
that in some cases the differences between them might not be necessary 
and might impair the ability of American businesses to export and 
compete internationally. It further recognizes that in meeting shared 
challenges involving health, safety, 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 and can reduce, eliminate, or prevent

[[Page 10000]]

unnecessary differences in regulatory requirements.
    This rule is different than comparable foreign regulations. For the 
reasons described in this preamble, these differences are justified 
because they have the potential to enhance safety.

Executive Order 13132 (Federalism)

    NHTSA has examined this 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]compliance 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 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 rule and 
does not foresee any potential State requirements that might conflict 
with it. We 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 rule and these laws. A 
vehicle equipped with a compliant and properly functioning ADB system 
should not glare other vehicles. Moreover, the rule requires an ADB-
equipped vehicle to provide the driver with a means of manually 
overriding the automatically provided beam. Therefore, if, for any 
reason the driver determines that the automatically provided beam is 
not appropriate, the driver can manually switch to the appropriate beam 
(e.g., lower beam). NHTSA does not intend this rule to 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 in this final rule. 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.\235\ 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 (1) ``[b]briefly provide sufficient evidence and analysis 
for determining whether to prepare an environmental impact statement or 
a finding of no significant impact'' and (2) ``[b]briefly discuss the 
purpose and need for the proposed action, alternatives . . ., and the 
environmental impacts of the proposed action and alternatives, and 
include a listing of agencies and persons consulted.'' 40 CFR 
1501.5(c). This section serves as the Final Environmental Assessment 
(Final EA).
---------------------------------------------------------------------------

    \235\ 42 U.S.C. 4332(2)(C).
---------------------------------------------------------------------------

Purpose and Need
    This notice 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 
the NPRM, NHTSA concluded that FMVSS No. 108 does not currently permit 
ADB technology.
Alternatives
    NHTSA 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. 
In the final rule, NHTSA incorporates elements from these standards, 
but departs from them in significant ways, which are also described 
above.
Environmental Impacts of the Proposed Action and Alternatives
    This final rule is anticipated to result in increased upper beam 
use as well as greater illumination provided by the adaptive driving 
beams (in patterns designed to prevent glare to other motorists). As a 
result, the primary

[[Page 10001]]

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.\236\ 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 
over illumination (excess artificial lighting for a specific 
activity).\237\ 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.\238\
---------------------------------------------------------------------------

    \236\ National Park Service, Light Pollution. https://www.nps.gov/subjects/nightskies/lightpollution.htm (last accessed 
Sept. 26, 2018).
    \237\ Chepesiuk, R. 2009. Missing the Dark: Health Effects of 
Light Pollution. Environmental Health Perspectives, 117(1), A20-A27.
    \238\ Id.
---------------------------------------------------------------------------

    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 rule requires that the part of an ADB beam 
that is cast near other vehicles not exceed the current lower 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 upper beam use and the sculpting of the adaptive driving 
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 not only reduce the potential for glare to 
other drivers but also limit the potential impact of light pollution.
    Second, we note that ADB systems remain optional. Because of the 
added costs associated with the technology, NHTSA does not anticipate 
that manufacturers would make these systems standard equipment in all 
their vehicle models at this time. Thus, only a percentage of the on-
road fleet will feature ADB systems, while new vehicles without the 
systems are 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).\239\ 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.
---------------------------------------------------------------------------

    \239\ 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 rule requires ADB 
systems to produce a lower beam at speeds below 20 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 should not experience changes in light 
levels produced from motor vehicles as a result of this rule. In 
moderately crowded, urban environments, nighttime vehicles may travel 
above 20 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 the adaptive 
driving beam. 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 final rule 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 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 rule compared to the other regulatory 
alternatives (ECE requirements and SAE J3069). For example, the rule 
requires that the area of unreduced intensity meet the upper beam 
minima and the area of reduced intensity meet the lower beam minima. 
The SAE standard only requires that the area of unreduced intensity 
meet the lower beam minima. However, NHTSA also proposes that the area 
of unreduced intensity may not exceed the upper beam maxima, whereas 
the SAE standard does not specify any maxima for the undimmed portion. 
Thus, while the final rule establishes requirements for minimum levels 
of light, it also limits the maximum level of light in the area of 
unreduced intensity; both differ from the SAE standard. This combined 
with the wide variations still permitted under the final rule and the 
SAE standard make it difficult to compare them with any level of 
certainty.

[[Page 10002]]

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.
Agencies and Persons Consulted
    This preamble describes the various materials, persons, and 
agencies consulted in the development of the proposal.
Finding of No Significant Impact
    I have reviewed this EA. Based on the EA, I conclude that any of 
the impacts anticipated to result from the alternatives under 
consideration will not have a significant effect on the human 
environment and that a ``finding of no significant impact'' is 
appropriate. This statement constitutes the agency's ``finding of no 
significant impact,'' and an environmental impact statement will not be 
prepared. 40 CFR 1501.6(a).

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 final rule 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 
final rule would fall under North American Industry Classification 
System (NAICS) No. 336111, Automobile Manufacturing, which has a size 
standard of 1,500 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 this rule. I certify that this 
rule will not have a significant economic impact on a substantial 
number of small entities. Most of the affected entities are not small 
businesses. The rule will not establish a mandatory requirement on 
regulated persons.

National Technology Transfer and Advancement Act and 1 CFR Part 51

    Under the National Technology Transfer and Advancement Act of 1995 
(NTTAA),\240\ ``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.'' \241\ However, if the use of such technical 
standards would be ``inconsistent with applicable law or otherwise 
impractical, a Federal agency or department may elect to use technical 
standards that are not developed or adopted by voluntary consensus 
standards bodies[.]'' \242\ 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 SAE. The NTTAA directs the 
agency to provide Congress, through OMB, explanations when the agency 
decides not to use available and applicable voluntary consensus 
standards. Circular A-119 directs that evaluating whether to use a 
voluntary consensus standard should be done on a case-by-case 
basis.\243\ An agency should consider, where applicable, factors such 
as the nature of the agency's statutory mandate and the consistency of 
the standard with that mandate.\244\
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    \240\ National Technology Transfer and Advancement Act of 1995, 
Public Law 104-113, 110 Stat. 775 (1996).
    \241\ Id. at Sec.  12(d)(1).
    \242\ Id. at Sec.  12(d)(3).
    \243\ Office of Management and Budget, Circular No. A-119, ] 
5(a)(i), Federal Participation in the Development and Use of 
Voluntary Consensus Standards and in Conformity Assessment 
Activities (Jan. 26, 2016).
    \244\ Id.
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    SAE has published a voluntary consensus standard (SAE J3069 
JUN2016) for ADB systems.\245\ The Competitive Enterprise Institute 
(CEI), in its comments, specifically referenced the NTTAA, arguing that 
the NPRM unnecessarily departed from SAE J3069.
---------------------------------------------------------------------------

    \245\ SAE has recently published a revised version, SAE J3069 
MAR2021.
---------------------------------------------------------------------------

    NHTSA has modified the proposal to more closely follow SAE J3069 
where warranted, but to deviate from that standard where necessary. The 
most important of these changes were specifying stationary test 
fixtures instead of dynamic stimulus vehicles and substantially 
simplifying the number and complexity of the test scenarios. However, 
there are several aspects of the final rule for which NHTSA ultimately 
concluded that deviation from SAE J3069 is warranted because SAE J3069 
did not adequately address glare or visibility. The major differences 
are summarized in Section VIII.O, Regulatory Alternatives. The 
preceding sections of this document discuss in detail the ways in which 
the final rule follows and differs from SAE J3069, and explain why we 
believe these departures are justified.
    The CIE 1931 Chromaticity Diagram was previously approved for 
incorporation by reference in the section where it appears as of 
February 6, 2012.

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

[[Page 10003]]

rulemaking modifies two existing information collection requirements. 
First, this rulemaking modifies the requirements for manufacturers to 
provide instructions for operating semiautomatic headlamp switching 
devices. Prior to this final rule, the standard required manufacturers 
to provide instructions on how to operate the device correctly, 
including: How to turn the automatic control on and off; how to adjust 
the sensitivity control; and any other specific instructions applicable 
to the device. This rule modifies the requirement by excluding ADB 
systems from the requirement to provide instructions on how to adjust 
the sensitivity control if they are not equipped with a sensitivity 
control. The rule also modifies the requirements regarding providing 
instructions for vehicle headlamp aiming devices (VHAD). Prior to this 
rule, the standard required manufacturers to provide instructions 
advising that the headlighting system is properly aimed if the 
appropriate vertical plane (as defined by the vehicle manufacturer) is 
perpendicular to both the longitudinal axis of the vehicle, and a 
horizontal plane when the vehicle is on a horizontal surface, and the 
VHAD is set at ``0'' vertical and ``0'' horizontal. The final rule 
changes the standard to require manufacturers to provide instructions 
advising the vehicle owner what to do if the headlighting system 
requires aiming using the VHAD.
    NHTSA is separately publishing a notice requesting comment on 
NHTSA's intention to request approval for a modification to its 
previously approved information collection request titled 
``Consolidated Vehicle Owner's Manual Requirements for Motor Vehicles 
and Motor Vehicle Equipment.'' The document (Docket Number: NHTSA-2021-
0059) will provide details about the burden associated with the 
information collection and will provide a 60-day comment period.

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 2016 results in $148 million 
(111.416/75.324 = 1.48). The assessment may be included in conjunction 
with other assessments, as it is here.
    This rule is not likely to result in expenditures by State, local 
or tribal governments of more than $148 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 final rule and has concluded that the requirements are the most 
cost-effective alternatives that achieve the objectives of the rule.

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 documents 
received into any of our dockets by the name of the individual 
submitting the document (or signing it, 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, (Volume 65, Number 70; Pages 19477-78) or you may visit 
www.dot.gov/privacy.html.

Appendices to the Preamble

Appendix A. Comparison of Oncoming Glare Limits to Table XIX Right-Side 
Photometric Maxima

    To analyze the dynamic track test procedure requirements in the 
narrow right-side region of the beam from 1R to 3R and compare it to 
the current Table XIX requirements (particularly .5 U, 1R-3R, which has 
a minimum of 500 cd and a maximum of 2,700 cd), the agency calculated 
the horizontal angle for each headlamp (right and left) at each extreme 
of each right curve. See Figure A.1. These calculations assume a 
headlamp mounting height of 0.4 m below the oncoming photometer height 
(1.1 m above ground), or a headlamp height of 0.7 m above the ground. 
Additionally, they assume a headlamp separation distance of 1.1 m and a 
lane width of 3.66 m.
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[GRAPHIC] [TIFF OMITTED] TR22FE22.036

[[Page 10005]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.037

    For the medium radius, right curve, the most stringent angle toward 
the right side of the beam pattern will occur on the 210 m curve at 
2.17 (right lamp) and 3.42 (left lamp) degrees right and 0.46U (close 
to 0.5U). As Stanley pointed out, this is very close to the 0.5U, 1R-3R 
line, for which Table XIX specifies a minimum of 500 cd and a maximum 
of 2,700 cd. The per lamp maximum of 2,250 cd implied by the applicable 
oncoming glare limit (1.8 lux) is slightly more stringent than 2,700 
cd.
    For the large radius right curve, the most stringent angle toward 
the right side of the beam pattern will occur on the 335 m curve at 
2.67 (right lamp) and 3.57 (left lamp) degrees right and 0.33U (below 
the 0.5U line). This angle (which is dependent on the mounting height 
of the lamps) is below the 0.5U, 1R-3R line. The implied maximum of 
1,470 per lamp is more stringent than 2,700 cd.

Appendix B. Example of Laboratory Photometric Testing of Adaptive 
Driving Beam

    As explained in the preamble, in conducting its compliance testing, 
NHTSA will request information from the manufacturer on how to power 
and control the headlamps. To test the adaptive driving beam, we will 
activate a headlamp in the goniometer according to the manufacturer's 
instructions to produce an adaptive driving beam pattern that is 
consistent with an ADB pattern that would appear in the real-world with 
areas of reduced intensity, unreduced intensity, and/or transition 
zone(s). Specific patterns will conform to any real-world scenario 
determined by NHTSA. The ADB pattern generated will result in light 
directed toward all the test points in Tables XVIII and XIX. The issue 
then becomes which fixed test point falls within an area of reduced 
intensity, an area of unreduced intensity, or a transition zone. NHTSA 
will have manufacturers identify the portion(s) of the adaptive beam 
are areas of reduced intensity and which are areas of unreduced 
intensity. The areas of reduced intensity must conform to the 
requirements for the test points in Table XIX that correspond to that 
area of reduced intensity. The area of unreduced intensity must conform 
to the requirements for the test points in Table XVIII that correspond 
to that area of unreduced intensity. Procedures for determining the 
transition for lower beams (similar to how the cutoff is determined, 
i.e., a scan) can be used to determine whether the transition zone 
exceeds 1 degree.
    For example, NHTSA could request from the manufacturer information 
on powering the headlamp and controlling it such that an area of 
reduced intensity area is centered horizontally around 0.5U 1.2R. A 
hypothetical isocandela pattern is provided in Table B.1. produced by 
the headlamp (simplified to a resolution of 0.1 degree for ease of 
visualization).

[[Page 10006]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.038

[[Page 10007]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.039

[[Page 10008]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.040

[[Page 10009]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.041

    In this area of reduced intensity, NHTSA would check to ensure that 
the applicable Table XIX minima and maxima are met. For this area of 
the beam pattern, we would check the following lines within the lower 
beam requirements.

1.5U 1R to 3R Min 200 cd
1.5U 1R to R Max 1,400 cd
0.5U 1R to 3R Max 2,700 cd

    NHTSA would scan along 1.5 U to determine at what location the 1.5 
U line begins to fail the lower beam photometric requirements. This 
establishes the beginning of the transition zone. In the hypothetical 
case shown above, the lower beam meets these requirements at 1.2R 
[1,027] (where we asked for an area of reduced intensity) and continues 
to comply at 1.3R [1,027] continuing right until 1.5U, 1.9R [4,020] 
where it fails the Maximum 1,400 cd limit. So, for this case the 
transition zone begins at 1.9 R. Similarly, the 0.5 U line complies 
with the lower beam at 1.2 R [550 cd]. The 0.5 U line continues to 
comply until, again, 1.9R. Considering this, the transition zone begins 
at 1.9R and can continue for no more than 1 degree, or through the 
location of 2.9R. As such, upper beam points extending past this 
location must be met. As such, the beam pattern must meet the upper 
beam test point 1U, 3R which requires a minimum of 5,000 cd for a UB2 
lamp. In this case, the value is 31,000 and therefore compliant with 
the area of unreduced intensity tested at that location. Additionally, 
the upper beam point H, 3R minimum of 15,000 must be met along with all 
the upper beam points at 6R, 9R, 12R and all points left of V. A 0.25 
degree re-aim is permitted in S14.2.5.5.
    Considering the left edge of the area of reduced intensity, we 
would scan along the 1.5 U and 0.5 U right side lines and discover that 
the transition zone begins at 0.4 degrees R (traveling to the left). As 
such, the transition zone is permitted to extend 1 degree to the left 
from the left edge, or through 0.5 degrees L. The ADB pattern is not 
required to produce a compliant upper beam at the test point location 
of H-V as that may still be within the transition zone. If, however, an 
ADB beam pattern is produced with the left edge of the transition zone 
beginning at an angle greater than 1 degree R, the upper beam H-V point 
must be met for the area of unreduced intensity.
    This example also demonstrates how, although no photometry 
requirements apply to the transition zone, the photometry in the 
transition zone is not unconstrained. In this example, the edge of the 
area of reduced intensity is at 1.8R. That means that it must be at 
least 200 cd but not more than 1400 cd. At the 3R point it must be at 
least 5,000 cd. The transition zone will be between these two points. 
With respect to potential concerns, illuminance above 1,400 cd is not 
the concern, some exceedance is expected as the light transitions. It 
might be a concern if the intensity drops below 200 cd, however, this 
is very unlikely. As the commenters point out, it is difficult 
physically, and not preferred by drivers to have such extreme cutoffs. 
There is no reason for a manufacturer to allow the intensity to drop 
below 200 cd through the transition zone.

Appendix C. ADB Performance With Motorcycle Test Fixture

    Our testing showed consistently poor performance when the ADB 
system was tested against the motorcycle fixture and lamps we are 
finalizing.\246\ See Table C.1. The agency is concerned that if ADB 
systems do not adequately react to motorcycles in the real world that 
any safety benefits provided by ADB introduction could be negated by 
additional glare related risk to motorcyclists. Many of the failures 
listed below are not attributable to headlamp beam pattern design but 
are fundamental failures of the ADB system to react to the motorcycle 
lamps installed on the test fixture.
---------------------------------------------------------------------------

    \246\ As mentioned earlier, in its recent revisions to SAE 
J3069, SAE revised the specifications for the placement of the 
illuminance meters (corresponding to two side-view mirrors) on the 
same direction motorcycle fixture so that they are now 0.4 m from 
the centerline of the rear position lamp as opposed to 0.2 m. This 
change would not be expected to meaningfully impact our test results 
because the vehicle we tested did not produce a particularly narrow 
reduced area as a result of recognizing a motorcycle as compared to 
a passenger car. As such, a 200 mm horizontal difference would have 
no meaningful impact on the applicability of the research.

                                              Table C.1--ADB Performance With Final Rule Motorcycle Fixture
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           15.0-29.9            30.0-59.9            60.0-119.9          120.0-220.0
--------------------------------------------------------------------------------------------------------------------------------------------------------
Oncoming.........................  Straight............           61  PASS...............  PASS...............  PASS...............  FAIL.
Same Direction...................  Straight............           61  PASS...............  PASS...............  PASS...............
Oncoming.........................  85-L................           26  FAIL...............  FAIL...............
Oncoming.........................  210-L...............           41  PASS...............  FAIL...............  FAIL...............  PASS.
Same Direction...................  210-L...............           41  FAIL...............  FAIL...............  FAIL...............
Oncoming.........................  210-R...............           41  PASS...............  FAIL...............
Oncoming.........................  335-L...............           51  PASS...............  PASS...............  FAIL...............  FAIL.
Oncoming.........................  335-R...............           51  PASS...............  FAIL...............  FAIL...............
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The plots below (Figure C.1) are representative of the types of 
failures we observed when testing. That is, the ADB system was often 
late in reacting to the test fixture.

[[Page 10010]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.042

    While we are confident in the realism of the finalized test 
procedure, we did consider potential sources of variation within the 
test to see if the safety need and practicality of the test could be 
better optimized. As part of this investigation, we considered the 
lamps that are installed on the fixture and compared the ADB systems 
performance using the lamps specified in SAE J3069. See Table C.2 and 
Figure C.1. The motorcycle lamps we have chosen are not the source of 
the system's lack of performance as similar failures were observed when 
using the SAE specified lamps.

                                              Table C.2--ADB Performance With SAE J3069 Motorcycle Fixture
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                           15.0-29.9            30.0-59.9            60.0-119.9          120.0-220.0
--------------------------------------------------------------------------------------------------------------------------------------------------------
Oncoming.........................  Straight............           61  PASS...............  PASS...............  FAIL...............  FAIL.
Same Direction...................  Straight............           61  PASS...............  PASS...............  PASS...............
Oncoming.........................  85-L................           26  FAIL...............  FAIL...............
Oncoming.........................  210-L...............           41  PASS...............  PASS...............  FAIL...............  PASS.
Same Direction...................  210-L...............           41  FAIL...............  FAIL...............  FAIL...............
Oncoming.........................  210-R...............           41  PASS...............  PASS...............
Oncoming.........................  335-L...............           51  PASS...............  PASS...............  FAIL...............  FAIL.
Oncoming.........................  335-R...............           51  PASS...............  PASS...............  FAIL...............
--------------------------------------------------------------------------------------------------------------------------------------------------------

                                                                                                                [GRAPHIC] [TIFF OMITTED] TR22FE22.043
                                                                                                                
    We also considered if the fixture itself was a contributing factor 
in the system's lack of performance when encountering motorcycles. This 
does not seem to be the case based on the 2015 research, which exposed 
those ADB systems, installed to a complete three-wheel motorcycle. Some 
of those vehicles also demonstrated a lack of ability to react to the 
motorcycle stimulus. That research observed that ``Motorcycle scenario 
values . . . show, on average, the Audi headlighting system produced 
substantially higher glare in the 30 to 120 m range, up to 
approximately 9 times greater than that seen for lower beam mode 
(quotient values ranging from 6.13 to 9.69) and ``preceding motorcycle 
scenarios appeared to challenge ADB's ability to maintain glare within 
derived lower beam limit values. In both the stationary and moving 
preceding motorcycle scenarios, ADB mode for all four test vehicles 
showed illuminance levels exceeding lower beam levels and exceeding 
lower

[[Page 10011]]

beam glare limit values in at least one distance range.'' \247\
---------------------------------------------------------------------------

    \247\ 2015 ADB Test Report, pp. 109, 114.
---------------------------------------------------------------------------

    Although, as discussed previously, we do not believe that the SAE 
test adequately replicates the real world, we also considered how well 
the vehicle we tested performed on the SAE J3069 test. Overall, it 
performed better against the SAE J3069 test then the finalized test, 
however it did have dramatic failures on that test well. Figure C.3 
depicts a sample of these failures.
BILLING CODE 4910-59-C
[GRAPHIC] [TIFF OMITTED] TR22FE22.044

    In conclusion, the agency has determined that ADB systems must 
protect motorcyclist against increases in glare in the same way as 
other motor vehicle drivers. We have considered the ability of ADB 
systems to achieve the finalized level of performance but are unwilling 
to degrade overall safety. As such, we are finalizing today's rule to 
include a fixture with a specified motorcycle headlamp and a taillamp 
and testing ADB systems using the same real-world geometries for the 
motorcycle fixture as for the car and truck fixture.

Appendix D. List of Comments Cited in Preamble

------------------------------------------------------------------------
          Commenter                            Comment ID
------------------------------------------------------------------------
AAA..........................  NHTSA-2018-0090-0158.
Alliance for Automotive        NHTSA-2018-0090-0219.
 Innovation.
Alliance of Automobile         NHTSA-2018-0090-0138.
 Manufacturers.
Association of Global          NHTSA-2018-0090-0182.
 Automakers.
Automotive Lighting North      NHTSA-2018-0090-0068.
 America.
Competitive Enterprise         NHTSA-2018-0090-0145.
 Institute.
Consumer Reports.............  NHTSA-2018-0090-0191.
Ford Motor Company...........  NHTSA-2018-0090-0162.
General Motors...............  NHTSA-2018-0090-0181.
GTB--The International         NHTSA-2018-0090-0070.
 Automotive Lighting and
 Light Signalling Expert
 Group.
Harley-Davidson Motor Company  NHTSA-2018-0090-0148.
HELLA GmbH & Co. KGaA........  NHTSA-2018-0090-0085.
Honda (American Honda Motor    NHTSA-2018-0090-0179.
 Company).
Insurance Institute for        NHTSA-2018-0090-0149.
 Highway Safety.
International Organization of  NHTSA-2018-0090-0089.
 Motor Vehicle Manufacturers.
Intertek.....................  NHTSA-2018-0090-0143.
Koito Manufacturing Company..  NHTSA-2018-0090-0173.
League of American Bicyclists  NHTSA-2018-0090-0157.
Mercedes-Benz USA............  NHTSA-2018-0090-0147.
Mobileye, An Intel company...  NHTSA-2018-0090-0140.
Montgomery, Bryan............  NHTSA-2018-0090-0069.
Motor & Equipment              NHTSA-2018-0090-0175.
 Manufacturers Association.
NAFA Fleet Management          NHTSA-2018-0090-0067.
 Association.
North American Lighting......  NHTSA-2018-0090-0163.
Osram Sylvania...............  NHTSA-2018-0090-0177.
Peterson, Brent..............  NHTSA-2018-0090-0030.
Robert Bosch.................  NHTSA-2018-0090-0159.

[[Page 10012]]

 
SAE International............  NHTSA-2018-0090-0167.
Seastrunk, Jay...............  NHTSA-2018-0090-0200.
SL Corporation...............  NHTSA-2018-0090-0183.
Society of Motor               NHTSA-2018-0090-0156.
 Manufacturers and Traders.
Stanley Electric Company.....  NHTSA-2018-0090-0189.
Subaru.......................  NHTSA-2018-0090-0217.
Texas Instruments............  NHTSA-2018-0090-0161.
Toyota Motor North America...  NHTSA-2018-0090-0172.
Transportation Safety          NHTSA-2018-0090-0193.
 Equipment Institute.
Truck and Engine               NHTSA-2018-0090-0165.
 Manufacturers Association.
United Drive-In Theatre        NHTSA-2018-0090-0153.
 Owners Association.
Valeo Lighting Systems.......  NHTSA-2018-0090-0142.
Victor Hunt..................  NHTSA-2018-0090-0028.
Volkswagen Group of America..  NHTSA-2018-0090-0154.
Zoox.........................  NHTSA-2018-0090-0178.
------------------------------------------------------------------------

List of Subjects in 49 CFR Part 571

    Imports, Motor vehicle safety, Motor vehicles, and Tires.

    In consideration of the foregoing, NHTSA amends 49 CFR part 571 as 
set forth below.

PART 571--FEDERAL MOTOR VEHICLE SAFETY STANDARDS

0
1. The authority citation for part 571 of title 49 continues to read as 
follows:

    Authority: 49 U.S.C. 322, 30111, 30115, 30117, 30166; delegation 
of authority at 49 CFR 1.95.

0
2. Amend Sec.  571.108 by:
0
a. Adding, in alphabetical order, definitions of ``Adaptive driving 
beam,'' ``Headlighting system midpoint'' and ``Transition zone'' to 
paragraph S4;
0
b. Revising the definition of ``Semiautomatic headlamp beam switching 
device'' in paragraph S4;
0
c. Revising paragraphs S9.4.1, S9.4.1.1, S9.4.1.2, S9.4.1.3, S9.4.1.4, 
and S9.4.1.5;
0
d. Adding paragraphs S9.4.1.5.1 through S9.4.1.5.3 in numerical order;
0
e. Revising paragraph S9.4.1.6;
0
f. Adding paragraphs S9.4.1.6.1 through S9.4.1.6.5 in numerical order;
0
g. Removing S9.4.1.7;
0
h. Revising the introductory text of paragraph S9.5;
0
i. Revising paragraphs S10.14.1, S10.15.1, S10.16.1, S10.18.8.1.2, and 
S10.18.8.2.1;
0
j. Adding paragraphs S14.9.3.12 through S14.9.3.12.6.3;
0
k. Revising the entries for ``Lower Beam Headlamps'' and ``Upper Beam 
Headlamps'' in table I-a and table I-c;
0
l. Adding tables XXI and XXII, and figures 23 through 30 in numerical 
order; and
0
m. Removing the appendix to the section.
    The revisions and additions read as follows:

Sec.  571.108  Standard No. 108; Lamps, reflective devices, and 
associated equipment.

* * * * *
S4 Definitions
    Adaptive driving beam means a long-range light beam for forward 
visibility, which automatically modifies portions of the projected 
light to reduce glare to traffic participants on an ongoing, dynamic 
basis.
* * * * *
    Headlighting system midpoint means the intersection of a horizontal 
plane through the test vehicle's headlamp light sources, a vertical 
plane through the test vehicle's headlamp light sources and a vertical 
plane through the test vehicle's centerline.
* * * * *
    Semiautomatic headlamp beam switching device is one which provides 
either automatic or manual control of beam switching at the option of 
the driver. When the control is automatic the headlamp beams switch 
automatically. When the control is manual, the driver may obtain either 
the lower beam or the upper beam manually regardless of the conditions 
ahead of the vehicle.
* * * * *
    Transition zone means the portion of an adaptive driving beam that 
occurs between an area of reduced intensity and an area of unreduced 
intensity.
* * * * *
    S9.4.1 Semiautomatic headlamp beam switching devices. As an 
alternative to S9.4, a vehicle may also be equipped with a 
semiautomatic means of switching beams that complies with 9.4.1.1 
though S9.4.1.4 and either 9.4.1.5 (Option 1) or 9.4.1.6 (Option 2).
    S9.4.1.1 Operating instructions. Each semiautomatic headlamp 
switching device must include operating instructions to permit a driver 
to operate the device correctly, including: How to turn the automatic 
control on and off; how to adjust the sensitivity control (for Option 1 
and if provided for Option 2); and any other specific instructions 
applicable to the device.
    S9.4.1.2 Manual override. The device must include a means 
convenient to the driver for switching the beam from the one provided.
    S9.4.1.3 Fail safe operation. A failure of the automatic control 
portion of the device must not result in the loss of manual operation 
and control of the upper and lower beams.
    S9.4.1.4 Automatic dimming indicator. There must be a convenient 
means of informing the driver when the device is controlling the 
headlamps automatically. For headlighting systems certified to Option 
1, the device shall not affect the function of the upper beam indicator 
light.
    S9.4.1.5--Option 1 (Semiautomatic headlamp beam switching devices 
other than Adaptive Driving Beam systems).
    S9.4.1.5.1 Lens accessibility. The device lens must be accessible 
for cleaning while the device is installed on a vehicle.
    S9.4.1.5.2 Mounting height. The center of the device lens must be 
mounted no less than 24 inches above the road surface.
    S9.4.1.5.3 Physical tests. Each semiautomatic headlamp beam 
switching device must be designed to conform to all applicable 
performance requirements of S14.9.3.11.
    S9.4.1.6--Option 2 (Adaptive Driving Beam systems).
    S9.4.1.6.1 The system must be capable of detecting system 
malfunctions (including but not limited to sensor obstruction).
    S9.4.1.6.2 If the system detects a malfunction that prevents the 
system from operating in automatic mode safely and in conformance with 
these requirements, the headlighting system must operate in manual mode 
until the

[[Page 10013]]

malfunction is corrected and must provide the driver with a visible 
warning that the malfunction exists.
    S9.4.1.6.3 When operating in manual mode, the system must provide 
only switching between lower and upper beams as provided in S9.4.
    S9.4.1.6.4 When operating in automatic mode, the system must only 
switch between lower, upper, and adaptive driving beams. The adaptive 
driving beams must be designed to conform to the requirements of this 
section.
    S9.4.1.6.4.1 The adaptive driving beams must consist only of 
area(s) of reduced intensity, area(s) of unreduced intensity, and 
transition zone(s).
    S9.4.1.6.4.2 The adaptive driving beams must be designed to conform 
to the photometry requirements of Table XXI when tested according to 
S14.9.3.12, and, for replaceable bulb headlighting systems, when using 
any replaceable light source designated for use in the system.
    S9.4.1.6.4.3 In an area of reduced intensity, the adaptive driving 
beams must be designed to conform to the photometric intensity 
requirements of Table XIX as specified in Table II for the specific 
headlamp unit and aiming method, when tested according to the procedure 
of S14.2.5, and, for replaceable bulb headlighting systems, when using 
any replaceable light source designated for use in the system.
    S9.4.1.6.4.4 In an area of unreduced intensity, the adaptive 
driving beams must be designed to conform to the photometric intensity 
requirements of Table XVIII as specified in Table II for the specific 
headlamp unit and aiming method, when tested according to the procedure 
of S14.2.5, and, for replaceable bulb headlighting systems, when using 
any replaceable light source designated for use in the system.
    S9.4.1.6.4.5 A transition zone not to exceed 1.0 degree in either 
the horizontal or vertical direction is permitted between an area of 
reduced intensity and an area of unreduced intensity. The Table XVIII 
and Table XIX photometric intensity requirements do not apply in a 
transition zone, except that the maximum at H-V in Table XVIII as 
specified in Table II for the specific headlamp unit and aiming method 
may not be exceeded at any point in a transition zone.
    S9.4.1.6.4.6 For vehicle speeds below 32 kph (20 mph), the system 
must provide only lower beams (unless manually overridden according to 
S9.4.1.2).
    S9.4.1.6.4.7 The adaptive driving beams must not be energized 
simultaneously with the lower or upper beams except as provided in 
Table II.
    S9.4.1.6.5 The adaptive driving beams may be provided by any 
combination of headlamps or light sources, provided parking lamps are 
installed. If parking lamps meeting the requirements of this standard 
are not required according to Table I and are not installed, the 
adaptive driving beams may be provided using any combination of 
headlamps but must include the outermost installed headlamps to show 
the overall width of the vehicle.
* * * * *
    S9.5 Upper beam headlamp indicator. Each vehicle must have a means 
for indicating to the driver when the upper beams of the headlighting 
system are activated. The upper beam headlamp indicator is not required 
to be activated when an Adaptive Driving Beam system is operating in 
automatic mode.
* * * * *
    S10.14.1 Installation. An integral beam headlighting system must 
consist of the correct number of designated headlamp units as specified 
for the applicable system in Table II-c. The units must have their 
upper and lower beams activated as specified in Table II-c, and their 
adaptive driving beams (if so equipped) activated as specified in 
S9.4.1.6.5. A system must provide in total not more than two upper 
beams, two lower beams, and, optionally, two adaptive driving beams.
* * * * *
    S10.15.1 Installation. A replaceable bulb headlighting system must 
consist of either two or four headlamps as specified for the applicable 
system in Table II-d. The headlamps must have their upper and lower 
beams activated as specified in Table II-d, and their adaptive driving 
beams (if so equipped) activated as specified in S9.4.1.6.5. A system 
must provide in total not more than two upper beams, two lower beams, 
and, optionally, two adaptive driving beams, and must incorporate not 
more than two replaceable light sources in each headlamp.
* * * * *
    S10.16.1 Installation. A combination headlighting system must 
consist of the correct number of designated headlamp units as specified 
for the applicable system in Table II-b. The units must have their 
upper and lower beams activated as specified in Table II-b, and their 
adaptive driving beams (if so equipped) activated as specified in 
S9.4.1.6.5. A system must provide in total not more than two upper 
beams, two lower beams, and, optionally, two adaptive driving beams. 
When installed on a motor vehicle, the headlamps (or parts thereof) 
that provide the lower beam must be of the same type and provide a 
symmetrical effective projected luminous lens area when illuminated.
* * * * *
    S10.18.8.1.2 Horizontal aim. The VHAD must include references and 
scales relative to the longitudinal axis of the vehicle necessary to 
assure correct horizontal aim for photometry and aiming purposes. A 
``0'' mark must be used to indicate alignment of the headlamps relative 
to the longitudinal axis of the vehicle. In addition, an equal number 
of graduations from the ``0'' position representing equal angular 
changes in the axis relative to the vehicle axis must be provided. If 
the horizontal VHAD is part of an adaptive driving beam system, 
S10.18.8.1.2.1 through S10.18.8.1.2.4 are not required.
* * * * *
    S10.18.8.2.1 Instructions must be provided either on a label 
permanently affixed to the vehicle adjacent to the VHAD, or in the 
operator's manual, advising the vehicle owner what to do if the 
headlighting system requires aiming using the VHAD.
* * * * *
    S14.9.3.12 Test for compliance with adaptive driving beam 
photometry requirements.
    S14.9.3.12.1 Test scenarios.
    S14.9.3.12.1.1 Any of the scenarios specified in Table XXII and 
Figures 27, 28, 29, and 30 may be tested. Where a range of values is 
specified, the vehicle shall be able to meet the requirements at all 
values within the range.
    S14.9.3.12.1.2 Any speed that conforms to the speeds specified for 
that test scenario will be selected for the test vehicle. The vehicle 
will achieve and maintain this speed  0.45 m/s (1 mph) 
prior to reaching, and then throughout, the measurement distance range 
specified for that scenario. Once the test speed is achieved and 
maintained, no sudden steering inputs, acceleration, braking, or 
anything that causes a change in vehicle pitch that affects the results 
of the test shall occur.
    S14.9.3.12.1.3 For test scenarios involving curves, any radius 
within the allowable range specified for that test scenario may be 
selected. The curve shall nominally consist of a constant radius path 
and be referenced to the headlighting system midpoint. The actual path 
of the test vehicle shall not deviate from the nominal path by more 
than +/- 0.5 m throughout the measurement distance range.

[[Page 10014]]

    S14.9.3.12.1.4 The test vehicle shall be driven within the lane and 
will not change lanes.
    S14.9.3.12.1.5 The measurement distance is the linear distance 
measured from the headlighting system midpoint to the most forward 
point of the relevant photometric receptor head mounted on the test 
fixture.
    S14.9.3.12.1.6 The illuminance values for each photometer, the 
instantaneous pitch of the test vehicle, and the measurement distance 
shall be recorded and synchronized throughout the measurement distance 
range specified for that scenario.
    S14.9.3.12.2 Compliance criteria. The maximum calculated 
illuminance for each measurement distance interval specified in Table 
XXI that is applicable to the scenario being tested, as determined 
according to S14.9.3.12.2.1, shall not exceed the applicable maximum 
illuminance listed in Table XXI.
    S14.9.3.12.2.1 The maximum calculated illuminance for each 
measurement distance interval specified in Table XXI that is applicable 
to the scenario being tested will be the highest illuminance recorded 
in that distance interval, excluding any illuminance value(s) that meet 
any of the following conditions:
    (a) A single illuminance value exceeding the applicable maximum 
illuminance in Table XXI (i.e., the illuminance value is not 
immediately preceded or followed by an illuminance value exceeding the 
applicable maximum illuminance); or
    (b) consecutive illuminance values occurring over a span of no more 
than 0.1 seconds exceeding the applicable maximum illuminance in Table 
XXI; or
    (c) any illuminance values collected while the vehicle pitch 
exceeds the average pitch recorded throughout the entire measurement 
distance range specified for that scenario in Table XXII by more than 
0.3 degrees.
    S14.9.3.12.3 Stimulus test fixtures. Testing shall be conducted 
using the stimulus test fixtures specified in this section and Figures 
23 through 26.
    S14.9.3.12.3.1 Headlamps. The headlamps specified in Fig. 23 
(Opposite Direction Car/Truck) shall be a right- and left-hand 2018 
Ford F-150 Halogen headlamp (part # KL3Z13008C KL3Z13008D) using any 
replaceable light source designated for use in the system and, 
separately, a right- and left-hand 2018 Toyota Camry LED headlamp (part 
# 8111006C40/8115006C40). The headlamps specified in Fig. 25 (Opposite 
Direction Motorcycle) shall be a 5.75-inch round headlamp kit from a 
2018 Harley Davidson Sportster (part #68297-05B) using an HB2 
replaceable light source. Each headlamp shall energize the lower beam 
only, powered at 12.8 volts DC +/- 500 mV when measured at the lamp 
terminals, and shall have been energized for a minimum of 5 minutes 
before each test trial. The measurement locations specified in Figures 
23 and 25 shall be measured to the optical axis marking of the 
headlamps.
    S14.9.3.12.3.2 Taillamps. The taillamps specified in Fig. 24 (Same 
Direction Car/Truck) shall be a right and left-hand 2018 Ford F-150 
incandescent rear combination lamp (part # JL3Z13405H/JL3Z13404H) and, 
separately, a right and left-hand 2018 Toyota Camry rear combination 
lamp (part # 81550-06730/81560-06730). The taillamps specified in Fig. 
26 (Same Direction Motorcycle) shall be a 2018 Harley Davidson Roadster 
layback LED taillamp assembly (part #67800355). The taillamps shall be 
powered at 12.8 volts DC +/- 500 mV when measured at the lamp terminals 
and shall have been energized for a minimum of 5 minutes before each 
test trial. The measurement locations specified in Figures 24 and 26 
shall be measured to the center of the taillamp.
    S14.9.3.12.3.3 Photometers. Photometers must be capable of a 
minimum measurement unit of 0.01 lux. The color response of the 
photometer must be corrected to that of the 1931 CIE Standard Observer 
(2-degree) Photopic Response Curve, as shown in the CIE 1931 
Chromaticity Diagram (incorporated by reference, see Sec.  571.5), with 
a cosine correction characteristic within 3%. The photometer lenses on 
the test fixture shall be clean and free from dirt and debris, and the 
photometers will be zero-calibrated for each test to account for 
ambient light. The illuminance values from the photometers shall be 
collected at a rate of at least 100 Hz and a maximum 25-degree angle of 
incidence.
    S14.9.3.12.3.4 The projection of the fixture lamp's optical axis 
onto the road surface shall be parallel to a tangent of the road edge 
at the location of the photometer.
    S14.9.3.12.3.5 The test fixture shall be centered in the lane.
    S14.9.3.12.4 Test vehicle preparation.
    S14.9.3.12.4.1 Tires on the test vehicle shall be inflated to the 
manufacturer's recommended cold inflation pressure  7 kPa 
(1 psi). If more than one recommendation is provided, the tires are 
inflated to the cold inflation pressure  7 kPa (1 psi) that 
corresponds to the lowest loaded condition listed.
    S14.9.3.12.4.2 Before initiating testing, if the test vehicle is 
equipped with a fuel tank it shall be filled to approximately 100% of 
capacity with the appropriate fuel and maintained to at least 75% 
capacity throughout the testing.
    S14.9.3.12.4.3 Headlamps on the test vehicle shall be aimed 
according to the vehicle manufacturer's instructions. The test vehicle 
shall be loaded within +/- 5 kg of the total vehicle weight during 
track testing prior to aiming the adaptive driving beam headlamps.
    S14.9.3.12.4.4 The adaptive driving beam system shall be adjusted 
according to the manufacturer's instructions.
    S14.9.3.12.4.5 To the extent practicable, adaptive driving beam 
system sensors and the windshield on the test vehicle (if an adaptive 
driving beam system sensor is behind the windshield) shall be clean and 
free of dirt and debris.
    S14.9.3.12.4.6 The headlamp lenses of the test vehicle shall be 
clean and free from dirt and debris.
    S14.9.3.12.4.7 The adaptive driving beam system shall be activated 
according to the manufacturer's instructions and all other 
independently controlled lamps, such as fog lamps, shall be turned off.
    S14.9.3.12.5 Test road
    S14.9.3.12.5.1 The test road shall have a longitudinal grade 
(slope) that does not exceed 2%.
    S14.9.3.12.5.2 The lane width shall be any width from 3.05 m (10 
ft) to 3.66 m (12 ft).
    S14.9.3.12.5.3 The lanes shall be adjacent to one another.
    S14.9.3.12.5.4 The tests are conducted on a uniform, solid-paved 
surface.
    S14.9.3.12.5.5 The test road surface may be concrete or asphalt and 
shall not be bright white.
    S14.9.3.12.5.6 The test road surface may have pavement markings but 
shall be free of retroreflective material or elements that affect the 
outcome of the test.
    S14.9.3.12.6 Other test parameters and conditions
    S14.9.3.12.6.1 Testing shall be conducted on dry pavement and with 
no precipitation.
    S14.9.3.12.6.2 Testing shall be conducted when the ambient 
illumination at the test road as recorded by the photometers is at or 
below 0.2 lux.
    S14.9.3.12.6.3 Photometer data signals shall be passed through a 
low-pass filter with a cutoff frequency of 35 Hz.
* * * * *

[[Page 10015]]

                                Table I-a--Required Lamps and Reflective Devices
----------------------------------------------------------------------------------------------------------------
         Lighting device           Number and color    Mounting location    Mounting height    Device activation
----------------------------------------------------------------------------------------------------------------
                  All Passenger Cars, Multipurpose Passenger Vehicles (MPV), Trucks, and Buses
----------------------------------------------------------------------------------------------------------------
Lower Beam Headlamps............  White, of a         On the front, at    Not less than 55.9  The wiring harness
                                   headlighting        the same height,    cm nor more than    or connector
                                   system listed in    symmetrically       137.2 cm.           assembly of each
                                   Table II.           about the                               headlighting
                                                       vertical                                system must be
                                                       centerline, as                          designed so that
                                                       far apart as                            only those light
                                                       practicable.                            sources intended
                                                                                               for meeting lower
                                                                                               beam photometrics
                                                                                               are energized
                                                                                               when the beam
                                                                                               selector switch
                                                                                               is in the lower
                                                                                               beam position,
                                                                                               and that only
                                                                                               those light
                                                                                               sources intended
                                                                                               for meeting upper
                                                                                               beam photometrics
                                                                                               are energized
                                                                                               when the beam
                                                                                               selector switch
                                                                                               is in the upper
                                                                                               beam position,
                                                                                               except for
                                                                                               certain systems
                                                                                               listed in Table
                                                                                               II and
                                                                                               semiautomatic
                                                                                               headlamp beam
                                                                                               switching devices
                                                                                               certified to
                                                                                               S9.4.1.6.
                                                                                              Steady burning,
                                                                                               except that may
                                                                                               be flashed for
                                                                                               signaling
                                                                                               purposes or (for
                                                                                               semiautomatic
                                                                                               headlamp beam
                                                                                               switching devices
                                                                                               certified to
                                                                                               S9.4.1.6) vary in
                                                                                               intensity for
                                                                                               adaptive driving
                                                                                               beam
                                                                                               functionality.
Upper Beam Headlamps............  White, of a         On the front, at    Not less than 22
                                   headlighting        the same height,    inches (55.9 cm)
                                   system listed in    symmetrically       nor more than 54
                                   Table II.           about the           inches (137.2 cm).
                                                       vertical
                                                       centerline, as
                                                       far apart as
                                                       practicable.
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

* * * * *

[[Page 10016]]

                                TABLE I-c--Required Lamps and Reflective Devices
----------------------------------------------------------------------------------------------------------------
         Lighting device           Number and color    Mounting location    Mounting height    Device activation
----------------------------------------------------------------------------------------------------------------
                                                 All Motorcycles
----------------------------------------------------------------------------------------------------------------
Lower Beam Headlamps............  White, of a         On the front, at    Not less than 22    The wiring harness
                                   headlighting        the same height,    inches (55.9 cm)    or connector
                                   system listed in    symmetrically       nor more than 54    assembly of each
                                   S10.17.             about the           inches (137.2 cm).  headlighting
                                                       vertical                                system must be
                                                       centerline, as                          designed so that
                                                       far apart as                            only those light
                                                       practicable. See                        sources intended
                                                       additional                              for meeting lower
                                                       requirements in                         beam photometrics
                                                       S10.17.1.1,                             are energized
                                                       S10.17.1.2, and                         when the beam
                                                       S10.17.1.3.                             selector switch
                                                                                               is in the lower
                                                                                               beam position,
                                                                                               and that only
                                                                                               those light
                                                                                               sources intended
                                                                                               for meeting upper
                                                                                               beam photometrics
                                                                                               are energized
                                                                                               when the beam
                                                                                               selector switch
                                                                                               is in the upper
                                                                                               beam position,
                                                                                               except for
                                                                                               certain systems
                                                                                               listed in Table
                                                                                               II and
                                                                                               semiautomatic
                                                                                               headlamp beam
                                                                                               switching devices
                                                                                               certified to
                                                                                               S9.4.1.6.
                                                                                              Steady burning,
                                                                                               except that may
                                                                                               be flashed for
                                                                                               signaling
                                                                                               purposes or (for
                                                                                               semiautomatic
                                                                                               headlamp beam
                                                                                               switching devices
                                                                                               certified to
                                                                                               S9.4.1.6) vary in
                                                                                               intensity for
                                                                                               adaptive driving
                                                                                               beam
                                                                                               functionality.
                                                                                              The upper beam or
                                                                                               the lower beam,
                                                                                               but not both, may
                                                                                               be wired to
                                                                                               modulate from a
                                                                                               higher intensity
                                                                                               to a lower
                                                                                               intensity in
                                                                                               accordance with
                                                                                               S10.17.5.
Upper Beam Headlamps............  White, of a         On the front, at    Not less than 55.9
                                   headlighting        the same height,    cm nor more than
                                   system listed in    symmetrically       137.2 cm.
                                   S10.17.             about the
                                                       vertical
                                                       centerline, as
                                                       far apart as
                                                       practicable. See
                                                       additional
                                                       requirements in
                                                       S10.17.1.1,
                                                       S10.17.1.2, and
                                                       S10.17.1.3.
 
                                                  * * * * * * *
----------------------------------------------------------------------------------------------------------------

* * * * *

      Table XXI--Adaptive Driving Beam Photometry Requirements (1)
------------------------------------------------------------------------
                                              Maximum
                                            illuminance       Maximum
    Measurement distance interval (m)        Opposite       illuminance
                                             direction    same direction
                                               (lux)           (lux)
------------------------------------------------------------------------
Greater than or equal to 15.0 and less               3.1            18.9
 than 30.0..............................
Greater than or equal to 30.0 and less               1.8            18.9
 than 60.0..............................
Greater than or equal to 60.0 and less               0.6             4.0
 than 120.0.............................
Greater than or equal to 120.0 and less              0.3             N/A
 than or equal to 220...................
------------------------------------------------------------------------
\(1)\ For purposes of determining conformance with these specifications,
  an observed value or a calculated value shall be rounded to the
  nearest 0.1 lux, in accordance with the rounding method of ASTM
  Practice E29 Using Significant Digits in Test Data to Determine
  Conformance with Specifications.

* * * * *

[[Page 10017]]

                                                  Table XXII--Adaptive Driving Beam System Test Matrix
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                     Test vehicle                          Radius of curve                       Superelevation    Measurement distance
          Scenario No.               speed (kph)         Orientation             (m.)          Curve direction         (%)              range (m)
--------------------------------------------------------------------------------------------------------------------------------------------------------
1...............................  96.6-112.7 [60-70  Opposite Direction.           Straight  N/A...............             0-2  Greater than or equal
                                               mph]                                                                               to 15 and less than or
                                                                                                                                  equal to 220.
2...............................   40.2-48.3 [25-30  Opposite Direction.             85-115  Left..............             0-2  Greater than or equal
                                               mph]                                                                               to 15 and less than
                                                                                                                                  60.
3...............................   64.4-72.4 [40-45  Opposite Direction.            210-250  Left..............             0-2  Greater than or equal
                                               mph]                                                                               to 15 and less than or
                                                                                                                                  equal to 150.
4...............................   80.5-88.5 [50-55  Opposite Direction.            335-400  Left..............             0-2  Greater than or equal
                                               mph]                                                                               to 15 and less than or
                                                                                                                                  equal to 220.
5...............................   64.4-72.4 [40-45  Opposite Direction.            210-250  Right.............             0-2  Greater than or equal
                                               mph]                                                                               to 15 and less than or
                                                                                                                                  equal to 50.
6...............................   80.5-88.5 [50-55  Opposite Direction.            335-400  Right.............             0-2  Greater than or equal
                                               mph]                                                                               to 15 and less than or
                                                                                                                                  equal to 70.
7...............................  96.6-112.7 [60-70  Same Direction.....           Straight  N/A...............             0-2  Greater than or equal
                                               mph]                                                                               to 15 and less than or
                                                                                                                                  equal to 100.
8...............................   64.4-72.4 [40-45  Same Direction.....            210-250  Left..............             0-2  Greater than or equal
                                               mph]                                                                               to 15 and less than or
                                                                                                                                  equal to 100.
--------------------------------------------------------------------------------------------------------------------------------------------------------

* * * * *
BILLING CODE 4910-59-P
[GRAPHIC] [TIFF OMITTED] TR22FE22.045

[[Page 10018]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.046

[GRAPHIC] [TIFF OMITTED] TR22FE22.047

[[Page 10019]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.048

[GRAPHIC] [TIFF OMITTED] TR22FE22.049

[[Page 10020]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.050

[GRAPHIC] [TIFF OMITTED] TR22FE22.051

[[Page 10021]]

[GRAPHIC] [TIFF OMITTED] TR22FE22.052

BILLING CODE 4910-59-C
* * * * *

0
3. Amend Subpart B by adding Appendix A to Sec.  571.108 to read as 
follows:
    Appendix A to Subpart B to Sec.  571.108 Table of Contents.
Sec.
571.108 Standard No. 108; Lamps, reflective devices, and associated 
equipment.
S1 Scope.
S2 Purpose.
S3 Application.
S4 Definitions.
S5 References to SAE publications.
S6 Vehicle requirements.
S6.1 Required lamps, reflective devices, and associated equipment by 
vehicle type.
S6.1.1 Quantity.
S6.1.1.1 Conspicuity systems.
S6.1.1.2 High-mounted stop lamps.
S6.1.1.3 Truck tractor rear turn signal lamps.
S6.1.1.4 Daytime running lamps.
S6.1.2 Color.
S6.1.3 Mounting location.
S6.1.3.3 License plate lamp.
S6.1.3.4 High-mounted stop lamps.
S6.1.3.4.1 Interior mounting.
S6.1.3.4.2 Accessibility.
S6.1.3.5 Headlamp beam mounting.
S6.1.3.5.1 Vertical headlamp arrangement.
S6.1.3.5.2 Horizontal headlamp arrangement.
S6.1.3.6 Auxiliary lamps mounted near identification lamps.
S6.1.4 Mounting height.
S6.1.4.1 High-mounted stop lamps.
S6.1.5 Activation.
S6.1.5.1 Hazard warning signal.
S6.1.5.2 Simultaneous beam activation.
S6.2 Impairment.
S6.2.3 Headlamp obstructions.
S6.3 Equipment combinations.
S6.4 Lens area, visibility and school bus signal lamp aiming.

[[Page 10022]]

S6.4.1 Effective projected luminous lens area requirements.
S6.4.2 Visibility.
S6.4.3 Visibility options.
S6.4.3(a) Lens area option.
S6.4.3(b) Luminous intensity option.
S6.4.4 Legacy visibility alternative.
S6.4.5 School bus signal lamp aiming.
S6.5 Marking.
S6.5.1 DOT marking.
S6.5.2 DRL marking.
S6.5.3 Headlamp markings.
S6.5.3.1 Trademark.
S6.5.3.2 Voltage and trade number.
S6.5.3.3 Sealed beam headlamp markings.
S6.5.3.4 Replaceable bulb headlamp markings.
S6.5.3.5 Additional headlamp markings.
S6.6 Associated equipment.
S6.6.3 License plate holder.
S6.7 Replacement equipment.
S6.7.1 General.
S6.7.2 Version of this standard.
S7 Signal lamp requirements.
S7.1 Turn signal lamps.
S7.1.1 Front turn signal lamps.
S7.1.1.1 Number.
S7.1.1.2 Color of light.
S7.1.1.3 Mounting location.
S7.1.1.4 Mounting height.
S7.1.1.5 Activation.
S7.1.1.6 Effective projected luminous lens area.
S7.1.1.7 Visibility.
S7.1.1.8 Indicator.
S7.1.1.9 Markings.
S7.1.1.10 Spacing to other lamps.
S7.1.1.10.2 Spacing measurement for non-reflector lamps.
S7.1.1.10.3 Spacing measurement for lamps with reflectors.
S7.1.1.10.4 Spacing based photometric multipliers.
S7.1.1.11 Multiple compartment lamps and multiple lamps.
S7.1.1.11.4 Lamps installed on vehicles 2032 mm or more in overall 
width.
S7.1.1.12 Ratio to parking lamps and clearance lamps.
S7.1.1.13 Photometry.
S7.1.1.14 Physical tests.
S7.1.2 Rear turn signal lamps.
S7.1.2.1 Number.
S7.1.2.2 Color of light.
S7.1.2.3 Mounting location.
S7.1.2.4 Mounting height.
S7.1.2.5 Activation.
S7.1.2.6 Effective projected luminous lens area.
S7.1.2.7 Visibility.
S7.1.2.8 Indicator.
S7.1.2.9 Markings.
S7.1.2.10 Spacing to other lamps.
S7.1.2.11 Multiple compartments and multiple lamps.
S7.1.2.11.4 Lamps installed on vehicles 2032 mm or more in overall 
width.
S7.1.2.12 Ratio to taillamps and clearance lamps.
S7.1.2.13 Photometry.
S7.1.2.14 Physical tests.
S7.1.3 Combined lamp bulb indexing.
S7.2 Taillamps.
S7.2.1 Number.
S7.2.2 Color of light.
S7.2.3 Mounting location.
S7.2.4 Mounting height.
S7.2.5 Activation.
S7.2.6 Effective projected luminous lens area.
S7.2.7 Visibility.
S7.2.8 Indicator.
S7.2.9 Markings.
S7.2.10 Spacing to other lamps.
S7.2.11 Multiple compartments and multiple lamps.
S7.2.11.4 Taillamps installed on vehicles 2032 mm or more in overall 
width.
S7.2.12 Ratio.
S7.2.13 Photometry.
S7.2.14 Physical tests.
S7.3 Stop lamps.
S7.3.1 Number.
S7.3.2 Color of light.
S7.3.3 Mounting location.
S7.3.4 Mounting height.
S7.3.5 Activation.
S7.3.6 Effective projected luminous lens area.
S7.3.7 Visibility.
S7.3.8 Indicator.
S7.3.9 Markings.
S7.3.10 Spacing to other lamps.
S7.3.11 Multiple compartments and multiple lamps.
S7.3.11.4 Lamps installed on vehicles 2032 mm or more in overall 
width.
S7.3.12 Ratio to taillamps.
S7.3.13 Photometry.
S7.3.14 Physical tests.
S7.3.15 Combined lamp bulb indexing.
S7.4 Side marker lamps.
S7.4.1 Number.
S7.4.2 Color of light.
S7.4.3 Mounting location.
S7.4.4 Mounting height.
S7.4.5 Activation.
S7.4.6 Effective projected luminous lens area.
S7.4.7 Visibility.
S7.4.8 Indicator.
S7.4.9 Markings.
S7.4.10 Spacing to other lamps.
S7.4.11 Multiple compartments and multiple lamps.
S7.4.12 Ratio.
S7.4.13 Photometry.
S7.4.13.2 Inboard photometry.
S7.4.14 Physical tests.
S7.5 Clearance and identification lamps.
S7.5.1 Number.
S7.5.2 Color of light.
S7.5.3 Mounting location.
S7.5.4 Mounting height.
S7.5.5 Activation.
S7.5.6 Effective projected luminous lens area.
S7.5.7 Visibility.
S7.5.8 Indicator.
S7.5.9 Markings.
S7.5.10 Spacing to other lamps.
S7.5.11 Multiple compartments and multiple lamps.
S7.5.12 Ratio.
S7.5.12.1 Clearance lamps.
S7.5.12.2 Identification lamps.
S7.5.13 Photometry.
S7.5.14 Physical tests.
S7.6 Backup lamps.
S7.6.1 Number.
S7.6.2 Color of light.
S7.6.3 Mounting location.
S7.6.4 Mounting height.
S7.6.5 Activation.
S7.6.6 Effective projected luminous lens area.
S7.6.7 Visibility.
S7.6.8 Indicator.
S7.6.9 Markings.
S7.6.10 Spacing to other lamps.
S7.6.11 Multiple compartments and multiple lamps.
S7.6.12 Ratio.
S7.6.13 Photometry.
S7.6.14 Physical tests.
S7.7 License plate lamps.
S7.7.1 Number.
S7.7.2 Color of light.
S7.7.3 Mounting location.
S7.7.4 Mounting height.
S7.7.5 Activation.
S7.7.6 Effective projected luminous lens area.
S7.7.7 Visibility.
S7.7.8 Indicator.
S7.7.9 Markings.
S7.7.10 Spacing to other lamps.
S7.7.11 Multiple compartments and multiple lamps.
S7.7.12 Ratio.
S7.7.13 Photometry.
S7.7.14 Physical tests.
S7.7.15 Installation.
S7.7.15.4 Incident light from single lamp.
S7.7.15.5 Incident light from multiple lamps.
S7.8 Parking lamps.
S7.8.1 Number.
S7.8.2 Color of light.
S7.8.3 Mounting location.
S7.8.4 Mounting height.
S7.8.5 Activation.
S7.8.6 Effective projected luminous lens area.
S7.8.7 Visibility.
S7.8.8 Indicator.
S7.8.9 Markings.
S7.8.10 Spacing to other lamps.
S7.8.11 Multiple compartments and multiple lamps.
S7.8.12 Ratio.
S7.8.13 Photometry.
S7.8.14 Physical tests.
S7.9 High-mounted stop lamps.
S7.9.1 Number.
S7.9.2 Color of light.
S7.9.3 Mounting location.
S7.9.4 Mounting height.
S7.9.5 Activation.
S7.9.6 Effective projected luminous lens area.
S7.9.7 Visibility.
S7.9.8 Indicator.
S7.9.9 Markings.
S7.9.10 Spacing to other lamps.
S7.9.11 Multiple compartments and multiple lamps.
S7.9.12 Ratio.
S7.9.13 Photometry.
S7.9.14 Physical tests.
S7.10 Daytime running lamps (DRLs).
S7.10.1 Number.
S7.10.2 Color of light.
S7.10.3 Mounting location.
S7.10.4 Mounting height.
S7.10.5 Activation.
S7.10.6 Effective projected luminous lens area.

[[Page 10023]]

S7.10.7 Visibility.
S7.10.8 Indicator.
S7.10.9 Markings.
S7.10.10 Spacing to other lamps.
S7.10.10.1 Spacing to turn signal lamps.
S7.10.11 Multiple compartments and multiple lamps.
S7.10.12 Ratio.
S7.10.13 Photometry.
S7.10.14 Physical tests.
S7.11 School bus signal lamps.
S7.11.1 Number.
S7.11.2 Color of light.
S7.11.3 Mounting location.
S7.11.4 Mounting height.
S7.11.5 Activation.
S7.11.6 Effective projected luminous lens area.
S7.11.7 Visibility.
S7.11.8 Indicator.
S7.11.9 Markings.
S7.11.10 Spacing to other lamps.
S7.11.11 Multiple compartments and multiple lamps.
S7.11.12 Ratio.
S7.11.13 Photometry.
S7.11.14 Physical tests.
S8 Reflective device requirements.
S8.1 Reflex reflectors.
S8.1.1 Number.
S8.1.2 Color.
S8.1.3 Mounting location.
S8.1.4 Mounting height.
S8.1.5 Activation.
S8.1.6 Effective projected luminous lens area.
S8.1.7 Visibility.
S8.1.8 Indicator.
S8.1.9 Markings.
S8.1.10 Spacing to other lamps or reflective devices.
S8.1.11 Photometry.
S8.1.12 Physical tests.
S8.1.13 Alternative side reflex reflector material.
S8.2 Conspicuity systems.
S8.2.1 Retroreflective sheeting.
S8.2.1.2 Retroreflective sheeting material.
S8.2.1.3 Certification marking.
S8.2.1.4 Application pattern.
S8.2.1.4.1 Alternating red and white materials.
S8.2.1.5 Application location.
S8.2.1.6 Application spacing.
S8.2.1.7 Photometry.
S8.2.2 Conspicuity reflex reflectors.
S8.2.2.1 Certification marking.
S8.2.2.2 Application pattern.
S8.2.2.2.1 Alternating red and white materials.
S8.2.2.2.2 White material.
S8.2.2.3 Photometry.
S8.2.3 Conspicuity system installation on trailers.
S8.2.3.1 Trailer rear.
S8.2.3.1.1 Element 1--alternating red and white materials.
S8.2.3.1.2 Element 2--white.
S8.2.3.1.3 Element 3--alternating red and white materials.
S8.2.3.2 Trailer side-alternating red and white materials.
S8.2.4 Conspicuity system installation on truck tractors.
S8.2.4.1 Element 1--alternating red and white materials.
S8.2.4.2 Element 2--white.
S9 Associated equipment requirements.
S9.1 Turn signal operating unit.
S9.1.2 Physical tests.
S9.2 Turn signal flasher.
S9.2.2 Physical tests.
S9.3 Turn signal pilot indicator.
S9.3.4 Indicator size and color.
S9.3.6 Turn signal lamp failure.
S9.4 Headlamp beam switching device.
S9.4.1 Semi-automatic headlamp beam switching device.
S9.4.1.1 Operating instructions.
S9.4.1.2 Manual override.
S9.4.1.3 Fail safe operation.
S9.4.1.4 Automatic dimming indicator.
S9.4.1.5 Option 1 (Semiautomatic Headlamp Beam Switching Devices 
other than Adaptive Driving Beam systems).
S9.4.1.5.1 Lens accessibility.
S9.4.1.5.2 Mounting height.
S9.4.1.5.3 Physical tests.
S9.4.1.6 Option 2 (Adaptive Driving Beam systems).
S9.4.1.7 Physical tests.
S9.5 Upper beam headlamp indicator.
S9.5.1 Indicator size and location.
S9.6 Vehicular hazard warning signal operating unit.
S9.6.2 Operating unit switch.
S9.6.3 Physical tests.
S9.7 Vehicular hazard warning signal flasher.
S9.7.2 Physical tests.
S9.8 Vehicular hazard warning signal pilot indicator.
S9.8.4 Indicator size and color.
S10 Headlighting system requirements.
S10.1 Vehicle headlighting systems.
S10.2 [Reserved].
S10.3 Number.
S10.4 Color of light.
S10.5 Mounting location.
S10.6 Mounting height.
S10.7 Activation.
S10.8 Effective projected luminous lens area.
S10.9 Visibility.
S10.10 Indicator.
S10.11 Markings.
S10.12 Spacing to other lamps.
S10.13 Sealed beam headlighting systems.
S10.13.1 Installation.
S10.13.2 Simultaneous aim.
S10.13.3 Photometry.
S10.13.4 Physical tests.
S10.14 Integral beam headlighting systems.
S10.14.1 Installation.
S10.14.2 Aimability.
S10.14.3 Simultaneous aim.
S10.14.4 Markings.
S10.14.5 Additional light sources.
S10.14.6 Photometry.
S10.14.7 Physical tests.
S10.15 Replaceable bulb headlighting systems.
S10.15.1 Installation.
S10.15.2 Aiming restrictions.
S10.15.3 Replacement lens reflector units.
S10.15.4 Markings.
S10.15.5 Additional light sources.
S10.15.6 Photometry.
S10.15.7 Physical tests.
S10.16 Combination headlighting systems.
S10.16.1 Installation.
S10.16.2 Photometry.
S10.16.3 Physical tests.
S10.17 Motorcycle headlighting systems.
S10.17.1 Installation.
S10.17.1.1 Single headlamp.
S10.17.1.2 Two headlamps with both beams.
S10.17.1.3 Two headlamps, upper beam and lower beam.
S10.17.2 Motorcycle replaceable bulb headlamp marking.
S10.17.3 Photometry.
S10.17.4 Physical tests.
S10.17.5 Motorcycle headlamp modulation system.
S10.17.5.1 Modulation.
S10.17.5.2 Replacement modulators.
S10.17.5.2.1 Replacement performance.
S10.17.5.2.2 Replacement instructions.
S10.18 Headlamp aimability performance requirements (except 
motorcycles).
S10.18.1 Headlamp mounting and aiming.
S10.18.2 Headlamp aiming systems.
S10.18.3 Aim adjustment interaction.
S10.18.4 Horizontal adjustment-visually aimed headlamp.
S10.18.5 Optical axis marking.
S10.18.5.1 Optical axis marking-vehicle.
S10.18.5.2 Optical axis marking-lamp.
S10.18.5.3 Optical axis marking-visual/optical aim headlamp.
S10.18.6 Moveable reflectors.
S10.18.7 External aiming.
S10.18.7.1 Headlamp aiming device locating plates.
S10.18.7.2 Nonadjustable headlamp aiming device locating plates.
S10.18.8 On-vehicle aiming.
S10.18.8.1 Aim.
S10.18.8.1.1 Vertical aim.
S10.18.8.1.2 Horizontal aim.
S10.18.8.2 Aiming instructions.
S10.18.8.3 Permanent calibration.
S10.18.8.4 Replacement units.
S10.18.8.5 Physical tests.
S10.18.9 Visual/optical aiming.
S10.18.9.1 Vertical aim, lower beam.
S10.18.9.1.1 Vertical position of the cutoff.
S10.18.9.1.2 Vertical gradient.
S10.18.9.1.3 Horizontal position of the cutoff.
S10.18.9.1.4 Maximum inclination of the cutoff.
S10.18.9.1.5 Measuring the cutoff parameter.
S10.18.9.2 Horizontal aim, lower beam.
S10.18.9.3 Vertical aim, upper beam.
S10.18.9.4 Horizontal aim, upper beam.
S10.18.9.5 Photometry.
S10.18.9.6 Visual/optical aiming identification marking.
S11 Replaceable light source requirements.
S11.1 Markings.
S11.2 Ballast markings.
S11.3 Gas discharge laboratory life.
S11.4 Physical tests.
S12 Headlamp concealment device requirements.
S12.7 Certification election.
S13 Replaceable headlamp lens requirements.
S14 Physical and photometry test procedures and performance 
requirements.
S14.1 General test procedures and performance requirements.
S14.1.2 Plastic optical materials.

[[Page 10024]]

S14.1.4 Samples.
S14.1.5 Laboratory facilities.
S14.2 Photometric test procedures.
S14.2.1 Photometry measurements for all lamps except license lamps, 
headlamps, and DRLs.
S14.2.1.1 Mounting.
S14.2.1.2 School bus signal lamp aiming.
S14.2.1.3 Measurement distance.
S14.2.1.4 Location of test points.
S14.2.1.5 Multiple compartment and multiple lamp photometry of turn 
signal lamps, stop lamps, and taillamps.
S14.2.1.6 Bulbs.
S14.2.2 License plate lamp photometry.
S14.2.2.1 Illumination surface.
S14.2.2.2 Test stations.
S14.2.3 Reflex reflector and retroreflective sheeting photometry.
S14.2.3.1 Mounting.
S14.2.3.2 Illumination source.
S14.2.3.3 Measurement distance.
S14.2.3.4 Test setup.
S14.2.3.5 Photodetector.
S14.2.3.6 Photometry surface.
S14.2.3.7 Procedure.
S14.2.3.8 Measurements.
S14.2.3.8.1 Reflex reflectors.
S14.2.3.8.2 Retroreflective sheeting.
S14.2.3.8.3 Reflex reflector photometry measurement adjustments.
S14.2.4 Daytime running lamp (DRL) photometry measurements.
S14.2.5 Headlamp photometry measurements.
S14.2.5.1 Mounting.
S14.2.5.3 Measurement distance.
S14.2.5.4 Seasoning and test voltage.
S14.2.5.5 Aiming.
S14.2.5.5.1 Mechanically aimable headlamps using an external aimer.
S14.2.5.5.2 Mechanically aimable headlamps equipped with a VHAD.
S14.2.5.5.3 Visually aimable lower beam headlamps-vertical aim.
S14.2.5.5.4 Visually aimable lower beam headlamps-horizontal aim.
S14.2.5.5.5 Visually aimable upper beam headlamps-vertical aim.
S14.2.5.5.6 Visually aimable upper beam headlamps-horizontal aim.
S14.2.5.5.7 Simultaneous aim Type F sealed beam headlamps and beam 
contributor integral beam headlamps.
S14.2.5.5.8 Motorcycle headlamp-upper beam headlamps designed to 
comply with Table XX.
S14.2.5.5.9 Motorcycle headlamp-lower beam headlamps designed to 
comply with Table XX.
S14.2.5.6 Positioner.
S14.2.5.7 Photometer.
S14.2.5.7.2 Sensor.
S14.2.5.8 Location of test points.
S14.2.5.9 Beam contributor photometry measurements.
S14.2.5.10 Moveable reflector aimed headlamp photometry 
measurements.
S14.3 Motorcycle headlamp out of focus test procedure and 
performance requirements.
S14.3.1 Procedure.
S14.3.2 Performance requirements.
S14.4 General test procedures and performance requirements.
S14.4.1 Color test.
S14.4.1.1 Samples.
S14.4.1.2 General procedure.
S14.4.1.3 Visual method.
S14.4.1.3.1 Visual method procedure.
S14.4.1.3.2 Visual method performance requirements.
S14.4.1.3.2.1 Red.
S14.4.1.3.2.2 Yellow (Amber).
S14.4.1.3.2.3 White.
S14.4.1.4 Tristimulus method.
S14.4.1.4.1 Tristimulus method procedure.
S14.4.1.4.2 Tristimulus method performance requirements.
S14.4.1.4.2.1 Red.
S14.4.1.4.2.2 Yellow (Amber).
S14.4.1.4.2.3 White (achromatic).
S14.4.1.4.2.4 Green.
S14.4.1.4.2.5 Restricted Blue.
S14.4.1.4.2.6 Signal Blue.
S14.4.2 Plastic optical materials tests.
S14.4.2.1 Samples.
S14.4.2.2 Outdoor exposure test.
S14.4.2.2.3 Procedure.
S14.4.2.2.4 Performance requirements.
S14.4.2.3 Heat test.
S14.4.2.3.1 Procedure.
S14.4.2.3.2 Performance requirements.
S14.5 Signal lamp and reflective device physical test procedures and 
performance requirements.
S14.5.1 Vibration test.
S14.5.1.1 Procedure.
S14.5.1.2 Performance requirements.
S14.5.2 Moisture test.
S14.5.2.1 Procedure.
S14.5.2.2 Performance requirements.
S14.5.3 Dust test.
S14.5.3.1 Samples.
S14.5.3.2 Procedure.
S14.5.3.3 Performance requirements.
S14.5.4 Corrosion test.
S14.5.4.1 Procedure.
S14.5.4.2 Performance requirements.
S14.6 Headlamp physical test procedures and performance 
requirements.
S14.6.1 Abrasion test.
S14.6.1.1 Procedure.
S14.6.1.1.1 Abrading pad.
S14.6.1.1.2 Abrading pad alignment.
S14.6.1.1.3 Abrasion test procedure.
S14.6.1.2 Performance requirements.
S14.6.2 Chemical resistance test.
S14.6.2.1 Procedure.
S14.6.2.1.1 Test fluids.
S14.6.2.1.2 Fluid application.
S14.6.2.1.3 Test duration.
S14.6.2.2 Performance requirements.
S14.6.3 Corrosion test.
S14.6.3.1 Procedure.
S14.6.3.2 Performance requirements.
S14.6.4 Corrosion-connector test.
S14.6.4.1 Procedure.
S14.6.4.2 Performance requirements.
S14.6.5 Dust test.
S14.6.5.1 Procedure.
S14.6.5.2 Performance requirements.
S14.6.6 Temperature cycle test and internal heat test.
S14.6.6.1 Samples.
S14.6.6.2 General procedure.
S14.6.6.3 Temperature cycle test.
S14.6.6.3.1 Procedure.
S14.6.6.3.2 Performance requirements.
S14.6.6.4 Internal heat test.
S14.6.6.4.1 Procedure.
S14.6.6.4.2 Performance requirements.
S14.6.7 Humidity test.
S14.6.7.1 Procedure.
S14.6.7.2 Performance requirements.
S14.6.8 Vibration test.
S14.6.8.1 Samples.
S14.6.8.2 Procedure.
S14.6.8.3 Performance requirements.
S14.6.9 Sealing test.
S14.6.9.1 Procedure.
S14.6.9.2 Performance requirements.
S14.6.10 Chemical resistance test of reflectors of replaceable lens 
headlamps.
S14.6.10.1 Procedure.
S14.6.10.1.1 Test fluids.
S14.6.10.1.2 Fluid application.
S14.6.10.1.3 Test duration.
S14.6.10.2 Performance requirements.
S14.6.11 Corrosion resistance test of reflectors of replaceable lens 
headlamps.
S14.6.11.1 Procedure.
S14.6.11.2 Performance requirements.
S14.6.12 Inward force test.
S14.6.12.1 Procedure.
S14.6.12.2 Performance requirements.
S14.6.13 Torque deflection test.
S14.6.13.1 Procedure.
S14.6.13.2 Performance requirements.
S14.6.14 Retaining ring test.
S14.6.14.1 Procedure.
S14.6.14.2 Performance requirements.
S14.6.15 Headlamp connector test.
S14.6.15.1 Procedure.
S14.6.15.2 Performance requirements.
S14.6.16 Headlamp wattage test.
S14.6.16.1 Procedure.
S14.6.16.2 Performance requirements.
S14.6.17 Aiming adjustment test-laboratory.
S14.6.17.1 Procedure.
S14.6.17.2 Performance requirements.
S14.6.18 Aiming adjustment test-on vehicle.
S14.6.18.1 Procedure.
S14.6.18.2 Performance requirements.
S14.7 Replaceable light source physical test procedures and 
performance requirements.
S14.7.1 Deflection test for replaceable light sources.
S14.7.1.1 Procedure.
S14.7.1.2 Performance requirements.
S14.7.2 Pressure test for replaceable light sources.
S14.7.2.1 Procedure.
S14.7.2.2 Performance requirements.
S14.7.3 Replaceable light source power and flux measurement 
procedure.
S14.7.3.1 Seasoning.
S14.7.3.1.1 Resistive filament source.
S14.7.3.1.2 Discharge source.
S14.7.3.2 Test voltage.
S14.7.3.3 Luminous flux measurement.
S14.7.3.3.1 Resistive filament light source setup.
S14.7.3.3.3.2 Discharge light source setup.
S14.8 Vehicle headlamp aiming devices (VHAD) physical test 
procedures and performance requirements.
S14.8.1 Samples.
S14.8.2 Scale graduation test.
S14.8.2.1 Procedure.
S14.8.2.2 Performance requirements.
S14.8.3 Cold scale graduation test.
S14.8.3.1 Procedure.
S14.8.3.2 Performance requirements.
S14.8.4 Hot scale graduation test.
S14.8.4.1 Procedure.
S14.8.4.2 Performance requirements.

[[Page 10025]]

S14.8.5 Thermal cycle test.
S14.8.5.1 Procedure.
S14.8.5.2 Performance requirements.
S14.8.6 Corrosion test.
S14.8.6.1 Procedure.
S14.8.6.2 Performance requirements.
S14.8.7 Photometry test.
S14.8.7.1 Procedure.
S14.8.7.2 Performance requirements.
S14.9 Associated equipment physical test procedures and performance 
requirements.
S14.9.1 Turn signal operating unit durability test.
S14.9.1.1 Power supply specifications.
S14.9.1.2 Procedure.
S14.9.1.3 Performance requirements.
S14.9.2 Vehicular hazard warning signal operating unit durability 
test.
S14.9.2.1 Procedure.
S14.9.2.2 Performance requirements.
S14.9.3 Turn signal flasher and vehicular hazard warning flasher 
tests.
S14.9.3.1 Standard test circuit.
S14.9.3.1.1 Test circuit setup.
S14.9.3.2 Power supply specifications.
S14.9.3.2.1 Starting time, voltage drop, and flash rate and percent 
current ``on'' time tests.
S14.9.3.2.2 Durability tests.
S14.9.3.3 Turn signal flasher starting time test.
S14.9.3.3.1 Samples.
S14.9.3.3.2 Procedure.
S14.9.3.3.3 Performance requirements.
S14.9.3.4 Turn signal flasher voltage drop test.
S14.9.3.4.1 Samples.
S14.9.3.4.2 Procedure.
S14.9.3.4.3 Performance requirements.
S14.9.3.5 Turn signal flasher flash rate and percent current ``on'' 
time test.
S14.9.3.5.1 Samples.
S14.9.3.5.2 Procedure.
S14.9.3.5.3 Performance requirements.
S14.9.3.6 Turn signal flasher durability test.
S14.9.3.6.1 Samples.
S14.9.3.6.2 Procedure.
S14.9.3.6.3 Performance requirements.
S14.9.3.7 Vehicular hazard warning signal flasher starting time 
test.
S14.9.3.7.1 Samples.
S14.9.3.7.2 Procedure.
S14.9.3.7.3 Performance requirements.
S14.9.3.8 Vehicular hazard warning signal flasher voltage drop test.
S14.9.3.8.1 Samples.
S14.9.3.8.2 Procedure.
S14.9.3.8.3 Performance requirements.
S14.9.3.9 Vehicular hazard warning signal flasher flash rate and 
percent ``on'' time test.
S14.9.3.9.1 Samples.
S14.9.3.9.2 Procedure.
S14.9.3.9.3 Performance requirements.
S14.9.3.10 Vehicular hazard warning signal flasher durability test.
S14.9.3.10.1 Samples.
S14.9.3.10.2 Procedure.
S14.9.3.10.3 Performance requirements.
S14.9.3.11 Semiautomatic headlamp beam switching device tests.
S14.9.3.11.1 Test conditions.
S14.9.3.11.2 Sensitivity test.
S14.9.3.11.2.1 Samples.
S14.9.3.11.2.2 Procedure.
S14.9.3.11.2.3 Performance requirements.
S14.9.3.11.2.3.1 Operating limits.
S14.9.3.11.3 Voltage regulation test.
S14.9.3.11.3.1 Procedure.
S14.9.3.11.3.2 Performance requirements.
S14.9.3.11.4 Manual override test.
S14.9.3.11.4.1 Procedure.
S14.9.3.11.4.2 Performance requirements.
S14.9.3.11.5 Warmup test.
S14.9.3.11.5.1 Procedure.
S14.9.3.11.5.2 Performance requirements.
S14.9.3.11.6 Temperature test.
S14.9.3.11.6.1 Procedure.
S14.9.3.11.6.2 Performance requirements.
S14.9.3.11.7 Dust test.
S14.9.3.11.7.1 Procedure.
S14.9.3.11.7.2 Performance requirements.
S14.9.3.11.8 Corrosion test.
S14.9.3.11.8.1 Procedure.
S14.9.3.11.8.2 Performance requirements.
S14.9.3.11.9 Vibration test.
S14.9.3.11.9.1 Procedure.
S14.9.3.11.9.2 Performance requirements.
S14.9.3.11.10 Sunlight test.
S14.9.3.11.10.1 Procedure.
S14.9.3.11.10.2 Performance requirements.
S14.9.3.11.11 Durability test.
S14.9.3.11.11.1 Procedure.
S14.9.3.11.11.2 Performance requirements.
S14.9.3.11.12 Return to upper beam test.
S14.9.3.11.12.1 Procedure.
S14.9.3.11.12.2 Performance requirements.
S14.9.3.12 Test for compliance with adaptive driving beam photometry 
requirements.
S14.9.3.12.1 Test Scenarios.
S14.9.3.12.2 Compliance Criteria.
S14.9.3.12.3 Stimulus test fixtures.
S14.9.3.12.4 Test vehicle preparation.
S14.9.3.12.5 Test road.
S14.9.3.12.6 Other test parameters and conditions.
Table I-a Required lamps and reflective devices All passenger cars, 
multipurpose passenger vehicles (MPV), trucks, and buses
Table I-b Required lamps and reflective devices All trailers
Table I-c Required lamps and reflective devices All motorcycles
Table II-a Headlighting systems Sealed beams
Table II-b Headlighting systems Combination
Table II-c Headlighting systems Integral beams
Table II-d Headlighting systems Replaceable bulb
Table III Marking requirements location
Table IV-a Effective projected luminous lens area requirements
Table IV-b Effective projected luminous lens area requirements
Table IV-c Effective projected luminous lens area requirements
Table V-a Visibility requirements of installed lighting devices
Table V-b Visibility requirements of installed lighting devices Lens 
area visibility option
Table V-c Visibility requirements of installed lighting devices 
Luminous intensity visibility option
Table V-d Visibility requirements of installed lighting devices 
(Legacy visibility alternative)
Table VI-a Front turn signal lamp photometry requirements
Table VI-b Front turn signal lamp photometry requirements
Table VII Rear turn signal lamp photometry requirements
Table VIII Taillamp photometry requirements
Table IX Stop lamp photometry requirements
Table X Side marker lamp photometry requirements
Table XI Clearance and identification lamps photometry requirements
Table XII Backup lamp photometry requirements
Table XIII-a Motorcycle turn signal lamp alternative photometry 
requirements
Table XIII-b Motor driven cycle stop lamp alternative photometry 
requirements
Table XIV Parking lamp photometry requirements
Table XV High-mounted stop lamp photometry requirements
Table XVI-a Reflex reflector photometry requirements
Table XVI-b Additional photometry requirements for conspicuity 
reflex reflectors
Table XVI-c Retroreflective sheeting photometry requirements
Table XVII School bus signal lamp photometry requirements
Table XVIII Headlamp upper beam photometry requirements
Table XIX-a Headlamp lower beam photometry requirements
Table XIX-b Headlamp lower beam photometry requirements
Table XIX-c Headlamp lower beam photometry requirements
Table XX Motorcycle and motor driven cycle headlamp photometry 
requirements
Table XXI Adaptive Driving Beam Photometry Requirements
Table XXII Adaptive Driving Beam Test Matrix
Figure 1 Chromaticity diagram
Figure 2 Flasher performance chart
Figure 3 Replaceable bulb headlamp aim pads
Figure 4 Headlamp connector test setup
Figure 5 Headlamp abrasion test fixture
Figure 6 Thermal cycle test profile
Figure 7 Dirt/Ambient test setup
Figure 8 Replaceable light source deflection test setup
Figure 9 Environmental test profile
Figure 10 Replaceable light source pressure test setup
Figure 11 Trailer conspicuity treatment examples
Figure 12-1 Trailer conspicuity detail I
Figure 12-2 Trailer conspicuity detail II
Figure 13 Tractor conspicuity treatment examples
Figure 14 92 x 150 Headlamp aim deflection test setup
Figure 15 Types G and H headlamp aim deflection test setup
Figure 16 Types A and E headlamp aim deflection test setup
Figure 17 Type B headlamp aim deflection test setup
Figure 18 Types C and D headlamp aim deflection test setup

[[Page 10026]]

Figure 19 License plate lamp target locations
Figure 20 License plate lamp measurement of incident light angle
Figure 21 Vibration test machine
Figure 22 Flasher standard test circuit
Figure 23 Car/Truck opposite direction stimulus test fixture 
dimensions
Figure 24 Car/Truck same direction stimulus test fixture dimensions
Figure 25 Motorcycle opposite direction stimulus test fixture 
dimensions
Figure 26 Motorcycle same direction stimulus test fixture dimensions
Figure 27 Opposite direction test scenarios
Figure 28 Same direction test scenarios
Figure 29 Left Curve Test Scenarios
Figure 30 Right Curve Test Scenarios
* * * * *

    Issued under authority delegated in 49 CFR 1.95, 501.4, and 
501.5.
Steven S. Cliff,
Deputy Administrator.
[FR Doc. 2022-02451 Filed 2-18-22; 8:45 am]
BILLING CODE 4910-59-P