[Federal Register Volume 90, Number 244 (Tuesday, December 23, 2025)]
[Notices]
[Pages 60228-60230]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-23762]
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DEPARTMENT OF TRANSPORTATION
Federal Motor Carrier Safety Administration
[Docket No. FMCSA-2024-0255]
Agency Information Collection Activities; Approval of a New
Information Collection Request: Study of Warning Devices for Stopped
Commercial Motor Vehicles
AGENCY: Federal Motor Carrier Safety Administration (FMCSA), Department
of Transportation (DOT).
ACTION: Notice and request for comments.
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SUMMARY: In accordance with the Paperwork Reduction Act of 1995, FMCSA
announces its plan to submit the Information Collection Request (ICR)
described below to the Office of Management and Budget (OMB) for review
and approval. This notice invites comments on a proposed information
collection titled ``Study of Warning Devices for Stopped Commercial
Motor Vehicles.'' It is an experimental study that requires data
collection for evaluating whether warning devices meaningfully
influence crash-relevant aspects of human performance in the presence
of a parked or disabled commercial motor vehicle (PDCMV), and if so,
how and to what extent. These data collection efforts are expected to
require the participation of 256 drivers. A total of 9 comments were
provided in response to the 60-day Federal Register notice (91 FR
1591). The total burden hours reported in the 60-day FR published on
January 8, 2025, has now been decreased by 128 hours after FMCSA
inadvertently included but has now removed the 128 hours from the
burden estimate. The 128 hours is the time estimated for respondents to
travel to and from the location where the collection of information
will occur.
DATES: Comments on this notice must be received on or before January
22, 2026.
ADDRESSES: Written comments and recommendations for the proposed
information collection should be submitted within 30 days of
publication of this notice to www.reginfo.gov/public/do/PRAMain. Find
this information collection by selecting ``Currently under 30-day
Review--Open for Public Comments'' or by using the search function.
FOR FURTHER INFORMATION CONTACT: Samuel White, Research Division, DOT,
FMCSA, 1200 New Jersey Avenue SE, Washington, DC 20590; 202-366-3068;
[email protected].
SUPPLEMENTARY INFORMATION:
[[Page 60229]]
Title: Study of Warning Devices for Stopped Commercial Motor
Vehicles
OMB Control Number: 2126-00XX.
Type of Request: New ICR.
Respondents: Drivers.
Estimated Number of Respondents: 256.
Estimated Time per Response: 2.0 to 2.5 Hours.
Expiration Date: This is a new ICR.
Frequency of Response: Once.
Estimated Total Annual Burden: 504.92 hours.
Background
PDCMVs on the road negatively impact traffic operations and
safety.\1\ To increase the conspicuity of PDCMVs and mitigate crash
risk, FMCSA requires specific warning devices to be carried \2\ on all
commercial motor vehicles (CMVs) and, except in the case of necessary
traffic stops, be deployed \3\ near the vehicle whenever it is stopped
on the road or shoulder. The Federal Motor Carrier Safety Regulations
prescribe specific rules \4\ concerning how and where the warning
devices must be placed, based on road and traffic attributes (e.g.,
whether the road is straight or curved, whether the vehicle is stopped
in a business or residential district, whether the road is divided or
undivided, etc.) as well as the presence of conditions affecting
visibility (e.g., time of day, physical obstructions, etc.). These
requirements follow from the basic notion that increasing the
conspicuity of a PDCMV makes it easier to see and recognize, thereby
reducing the risk of a crash involving passing motorists.
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\1\ Roberts, G. L., & Lynn, C. (2003). Passenger vehicle crashes
into stationary large trucks: incidence and possible countermeasures
(No. VTRC 03-CR17). Virginia Transportation Research Council.
\2\ 49 CFR 393.95. (2024). Emergency equipment on all power
units. https://www.ecfr.gov/current/title-49/section-393.95.
\3\ 49 CFR 392.22. (2024). Emergency signals; stopped commercial
motor vehicles. https://www.ecfr.gov/current/title-49/section-392.22.
\4\ Placement of warning devices--Special rules. 49 CFR
392.22(b)(2) (1998). https://www.ecfr.gov/current/title-49/part-392#p-392.22(b)(2).
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In addition, the National Highway Traffic Safety Administration
(NHTSA) prescribes performance and design specifications \5\ for
warning devices under 49 CFR 571.125 of the Federal Motor Vehicle
Safety Standards (FMVSS). For instance, this standard establishes
minimum specifications for factors affecting the conspicuity (including
reflectivity, color, luminance) of warning triangles, the most commonly
utilized type of warning device (due to their reusability, shelf life,
and fire-risk safety concerns compared to flares or fuses). The purpose
of this standard is ``to assure that the warning devices can be readily
observed during daytime and nighttime lighting conditions, have a
standardized shape for quick message recognition, and perform properly
when deployed.'' \6\
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\5\ FMVSS no. 125; Warning devices. 49 CFR 571.125 (2012).
https://www.ecfr.gov/current/title-49/subtitle-B/chapter-V/part-571/subpart-B/section-571.125.
\6\ FMVSS; Warning devices, 58 FR 27514 (May 10, 1993). https://archives.federalregister.gov/issue_slice/1993/5/10/27507-27517.pdf#page=8.
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Public interest in warning device requirements for PDCMVs has
increased in recent years for several reasons. For example, advances in
automated driving system (ADS) technology have raised critical
questions regarding potential barriers to regulatory compliance with
warning device safety standards \7\ and regulations \8\ which reference
or require a ``driver.'' In addition, alternative types of warning
devices developed by industry, including those intended to increase
driver safety during device deployment, have resulted in multiple
applications for exemption from the corresponding safety
regulations.9 10 These recent issues related to warning
device requirements also call attention to the historically unresolved
questions of whether the use of such devices improves traffic safety
and, if so, how and to what extent.
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\7\ Kim, A., Perlman, D., Bogard, D., & Harrington, R. (2016).
Review of federal motor vehicle safety standards (FMVSS) for
automated vehicles. John A. Volpe National Transportation Systems
Center, for NHTSA and USDOT Intelligent Transportation Systems Joint
Program Office. https://rosap.ntl.bts.gov/view/dot/12260.
\8\ Perlman, D., Bogard, D., Epstein, A., Santalucia, A., & Kim,
A. (2018). Review of the federal motor carrier safety regulations
for automated commercial vehicles: Preliminary assessment of
interpretation and enforcement challenges, questions, and gaps
(FMCSA-RRT-17-013). John A. Volpe National Transportation Systems
Center. https://rosap.ntl.bts.gov/view/dot/35426.
\9\ Parts and accessories necessary for safe operation; Pi
Variables, Inc; Application for an exemption, 88 FR 40920 (June 22,
2023). https://www.govinfo.gov/content/pkg/FR-2023-06-22/pdf/2023-13205.pdf.
\10\ Parts and accessories necessary for safe operation;
Exemption application from Waymo LLC, and Aurora Operations, Inc.,
88 FR 13489 (Mar. 3, 2023). https://www.govinfo.gov/content/pkg/FR-2023-03-03/pdf/2023-04385.pdf.
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Past attempts by the Federal Highway Administration
(FHWA)11 12 and other researchers \13\ to answer those
questions yielded generally inconclusive or inconsistent results, which
possibly influenced NHTSA's past decision not to pursue conducting its
own research on the topic.\14\ FMCSA (previously under FHWA) itself has
never conducted experimental research on the impact of using warning
devices. As the only regulatory authority which still requires CMV
operators to use warning devices, the responsibility to answer these
questions finally and definitively is best charged to FMCSA.
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\11\ Lyles, R. W. (1980). Effective warning devices for parked/
disabled vehicles (No. FHWA-RD-80-65 Final Rpt.). University of
Maine, Orono, for Federal Highway Administration.
\12\ Knoblauch, R.L., & Tobey, H.N. (1980). Safety aspects of
using vehicle hazard warning lights, Volume 2 (No. FHWA/RD-80-102).
Biotechnology, Inc., for Federal Highway Administration.
\13\ Allen, M.J., Miller, S.D., & Short, J.L. (1973). The effect
of flares and triangular distress signals on highway traffic.
Optometry and Vision Science, 50(4), 305-315.
\14\ Federal motor vehicle safety standards; Warning devices, 59
FR 49586 (September 29,1994).https://archives.federalregister.gov/issue_slice/1994/9/29/49585-49591.pdf#page=2.
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Given the increasing focus on ADS, questions surrounding the safety
of CMV drivers when deploying warning devices, and the availability of
new technology and alternative devices since these questions were last
explored in the 1980s, there is a need to thoroughly evaluate the
effectiveness of warning devices under current regulations. In
addition, advanced research instruments unavailable or not in use at
the time of all past research on this topic are now in common use and
would permit far more sophisticated analyses of the effects of warning
devices on driver behavior. This includes sensors which can precisely
measure and record the location of vehicles (e.g., differential Global
Positioning System), eye-tracking devices which allow the researcher to
determine the precise moment when a driver first glanced at a PDCMV,
and instrumented vehicles which record accurate, high-frequency data
related to drivers' interactions with a vehicle's controls.
FMCSA plans to implement these modern tools in a controlled
experiment at a closed-course, state-of-the-art driving research
facility that will allow the most comprehensive examination of the
effects of warning devices to date. The results of the study may
support future rulemaking related to warning devices and provide
baseline data necessary to inform Agency decisions on exemption
applications for alternative warning device products.
FMCSA published the 60-day Federal Register notice on January 8,
2025, and the comment period closed on March 10, 2025 (90 FR 1591). A
total of nine comments were received from the public. These comments
revolved around nine themes: regulatory considerations and impact,
environment or condition-based study factors, study factors for other
devices, automated vehicle considerations, safety benefits of
[[Page 60230]]
and effectiveness of warning devices, and risks or challenges with
warning devices. These are all important comments for FMCSA to consider
while conducting the study or when making decisions based on the
results of the study. However, none of the comments directly address
the proposed information collection or its associated costs/impacts. As
such, FMCSA summarizes the comments but provides no response. Many
comments touched on multiple issues; however, the comments below are
organized based on the primary feedback provided.
Regulatory Considerations and Impact
There is widespread recognition that regulatory gaps and
complexities hinder effective deployment and use of warning devices.
Commenters noted that current rules do not adequately address the
overuse of warning lights, and that knowledge gaps continue to weaken
the regulatory framework's effectiveness. Additionally, legal loopholes
and the complexity of implementing regulations were seen as barriers to
the adoption of improved safety measures. Nonetheless, many comments
supported FMCSA's ongoing regulatory efforts and encouraged further
research to improve and modernize safety rules.
Environment or Condition-Based Study Factors
Environmental factors were a consistent theme, with many comments
highlighting how visibility issues--compounded by driver inattention,
curves in the road, and lack of rumble strips--reduce the effectiveness
of warning devices. Visibility varies significantly across road types,
making it essential for studies to account for these conditions.
Several comments advocated for studies to explicitly consider how
different environmental scenarios impact both warning device
performance and driver response.
Study Factors for Other Devices
The public expressed concerns about the reliability and
effectiveness of alternative warning devices. Some noted that excessive
or competing lights, such as flashing beacons, can confuse drivers and
reduce recognition of genuine hazards. Others raised the issue of power
failure risks in beacons and the failure of some warning devices in
real-world conditions. There was strong support for the evaluation of
new warning technologies and a call to remain open to innovative
solutions that might enhance safety outcomes.
Automated Vehicle Considerations
With deployment nearing of driver-out ADS-equipped CMVs, commenters
raised important questions about how these technologies interface with
existing safety requirements. Many pointed out that automated vehicles
(AVs) lack the ability to deploy warning devices which introduces new
regulatory challenges. Concerns included the need for AVs to have
redundant safety systems and the potential mismatch between other
driver expectations and AV capabilities. The comments emphasized the
need for additional human-factors research, particularly regarding how
drivers maintain attention and readiness to assume control of ADS-
equipped CMVs. There was also a call for developing specific safety
solutions for ADS-equipped CMVs and addressing gaps in AV breakdown
procedures.
Safety Benefits of and Effectiveness of Warning Devices
Despite some concerns, many commenters acknowledged the critical
role of warning devices in preventing accidents. Proper use of these
devices was praised for offering early hazard detection and for being
simple yet effective. The comments reinforced the idea that even basic
tools can provide significant safety benefits when deployed correctly.
Public feedback also urged FMCSA to validate the effectiveness of these
tools through research and ensure that any new safety technologies meet
or exceed this benchmark.
Risks or Challenges With Warning Devices
The misuse or overuse of warning devices was a key concern, as it
can reduce their clarity and effectiveness in signaling real hazards.
Inattentive drivers, outdated devices, and the risk of device placement
on the roadside were all cited as challenges. Some commenters also
mentioned that certain warning devices may be dangerous, especially
when their deployment puts drivers at risk. These concerns underscore
the need for updated regulations and evaluations that reflect current
and emerging road conditions and technologies.
Public Comments Invited: You are asked to comment on any aspect of
this information collection, including: (1) whether the proposed
collection is necessary for the performance of FMCSA's functions; (2)
the accuracy of the estimated burden; (3) ways for FMCSA to enhance the
quality, usefulness, and clarity of the collected information; and (4)
ways that the burden could be minimized without reducing the quality of
the collected information.
Issued under the authority of 49 CFR 1.87.
Jonathan Mueller,
Acting Associate Administrator, Office of Research and Registration.
[FR Doc. 2025-23762 Filed 12-22-25; 8:45 am]
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