Development of Guidelines for Vehicle and Equipment Marking and Lighting (2024)

Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

2024 N A T I O N A L C O O P E R A T I V E H I G H W A Y R E S E A R C H P R O G R A M NCHRP RESEARCH REPORT 1085 Development of Guidelines for Vehicle and Equipment Marking and Lighting Gerald Ullman Laura Higgins Susan Chrysler Boniphace Kutela Texas A&M Transportation Institute The Texas A&M University System College Station, TX Je Muttart Suntasy Gernhard-Macha Crash Safety Research Center, LLC East Hampton, CT Subscriber Categories Highways • Safety and Human Factors Research sponsored by the American Association of State Highway and Transportation Ofcials in cooperation with the Federal Highway Administration

NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM Systematic, well-designed, and implementable research is the most effective way to solve many problems facing state departments of transportation (DOTs) administrators and engineers. Often, highway problems are of local or regional interest and can best be studied by state DOTs individually or in cooperation with their state universities and others. However, the accelerating growth of highway transporta- tion results in increasingly complex problems of wide interest to high- way authorities. These problems are best studied through a coordinated program of cooperative research. Recognizing this need, the leadership of the American Association of State Highway and Transportation Officials (AASHTO) in 1962 ini- tiated an objective national highway research program using modern scientific techniques—the National Cooperative Highway Research Program (NCHRP). NCHRP is supported on a continuing basis by funds from participating member states of AASHTO and receives the full cooperation and support of the Federal Highway Administration (FHWA), United States Department of Transportation, under Agree- ment No. 693JJ31950003. The Transportation Research Board (TRB) of the National Academies of Sciences, Engineering, and Medicine was requested by AASHTO to administer the research program because of TRB’s recognized objectivity and understanding of modern research practices. TRB is uniquely suited for this purpose for many reasons: TRB maintains an extensive com- mittee structure from which authorities on any highway transportation subject may be drawn; TRB possesses avenues of communications and cooperation with federal, state, and local governmental agencies, univer- sities, and industry; TRB’s relationship to the National Academies is an insurance of objectivity; and TRB maintains a full-time staff of special- ists in highway transportation matters to bring the findings of research directly to those in a position to use them. The program is developed on the basis of research needs iden- tified by chief administrators and other staff of the highway and transportation departments, by committees of AASHTO, and by the FHWA. Topics of the highest merit are selected by the AASHTO Special Committee on Research and Innovation (R&I), and each year R&I’s recommendations are proposed to the AASHTO Board of Direc- tors and the National Academies. Research projects to address these topics are defined by NCHRP, and qualified research agencies are selected from submitted proposals. Administration and surveillance of research contracts are the responsibilities of the National Academies and TRB. The needs for highway research are many, and NCHRP can make significant contributions to solving highway transportation problems of mutual concern to many responsible groups. The program, however, is intended to complement, rather than to substitute for or duplicate, other highway research programs. Published research reports of the NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM are available from Transportation Research Board Business Office 500 Fifth Street, NW Washington, DC 20001 and can be ordered through the Internet by going to https://www.mytrb.org/MyTRB/Store/default.aspx Printed in the United States of America NCHRP RESEARCH REPORT 1085 Project 05-24 ISSN 2572-3766 (Print) ISSN 2572-3774 (Online) ISBN 978-0-309-70934-7 Library of Congress Control Number 2023952227 © 2024 by the National Academy of Sciences. National Academies of Sciences, Engineering, and Medicine and the graphical logo are trade- marks of the National Academy of Sciences. All rights reserved. COPYRIGHT INFORMATION Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or persons who own the copyright to any previously published or copyrighted material used herein. Cooperative Research Programs (CRP) grants permission to reproduce material in this publication for classroom and not-for-profit purposes. Permission is given with the understanding that none of the material will be used to imply TRB, AASHTO, APTA, FAA, FHWA, FTA, GHSA, or NHTSA endorsement of a particular product, method, or practice. It is expected that those reproducing the material in this document for educational and not-for-profit uses will give appropriate acknowledgment of the source of any reprinted or reproduced material. For other uses of the material, request permission from CRP. NOTICE The research report was reviewed by the technical panel and accepted for publication according to procedures established and overseen by the Transportation Research Board and approved by the National Academies of Sciences, Engineering, and Medicine. The opinions and conclusions expressed or implied in this report are those of the researchers who performed the research and are not necessarily those of the Transportation Research Board; the National Academies of Sciences, Engineering, and Medicine; the FHWA; or the program sponsors. The Transportation Research Board does not develop, issue, or publish standards or spec- ifications. The Transportation Research Board manages applied research projects which provide the scientific foundation that may be used by Transportation Research Board sponsors, industry associations, or other organizations as the basis for revised practices, procedures, or specifications. The Transportation Research Board; the National Academies of Sciences, Engineering, and Medicine; and the sponsors of the National Cooperative Highway Research Program do not endorse products or manufacturers. Trade or manufacturers’ names or logos appear herein solely because they are considered essential to the object of the report.

e National Academy of Sciences was established in 1863 by an Act of Congress, signed by President Lincoln, as a private, non- governmental institution to advise the nation on issues related to science and technology. Members are elected by their peers for outstanding contributions to research. Dr. Marcia McNutt is president. e National Academy of Engineering was established in 1964 under the charter of the National Academy of Sciences to bring the practices of engineering to advising the nation. Members are elected by their peers for extraordinary contributions to engineering. Dr. John L. Anderson is president. e National Academy of Medicine (formerly the Institute of Medicine) was established in 1970 under the charter of the National Academy of Sciences to advise the nation on medical and health issues. Members are elected by their peers for distinguished contributions to medicine and health. Dr. Victor J. Dzau is president. e three Academies work together as the National Academies of Sciences, Engineering, and Medicine to provide independent, objective analysis and advice to the nation and conduct other activities to solve complex problems and inform public policy decisions. e National Academies also encourage education and research, recognize outstanding contributions to knowledge, and increase public understanding in matters of science, engineering, and medicine. Learn more about the National Academies of Sciences, Engineering, and Medicine at www.nationalacademies.org. e Transportation Research Board is one of seven major program divisions of the National Academies of Sciences, Engineering, and Medicine. e mission of the Transportation Research Board is to mobilize expertise, experience, and knowledge to anticipate and solve complex transportation-related challenges. e Board’s varied activities annually engage about 8,500 engineers, scientists, and other transportation researchers and practitioners from the public and private sectors and academia, all of whom contribute their expertise in the public interest. e program is supported by state transportation departments, federal agencies including the component administrations of the U.S. Department of Transportation, and other organizations and individuals interested in the development of transportation. Learn more about the Transportation Research Board at www.TRB.org.

C O O P E R A T I V E R E S E A R C H P R O G R A M S AUTHOR ACKNOWLEDGMENTS The research reported herein was performed under NCHRP Project 05-24 by the Texas A&M Trans- portation Institute of the Texas A&M University System, under the fiscal administration of the Texas A&M Sponsored Research Services. Crash Safety Research Center, LLC, served as a subcontractor on this research. Gerald Ullman was the principal investigator. The other authors of this report are Laura Higgins, Susan Chrysler, Boniphace Kutela, Jeff Muttart, and Suntasy Gernhard-Macha. The work was performed under the general supervision of Dr. Ullman. The authors gratefully acknowledge the assistance of numerous state and municipal department of transportation personnel who provided information regarding their vehicle marking and warning light practices. The authors gratefully acknowledge the assistance of staff from Whelen Engineering, Wanco, and Area Wide Protective in the performance of the various research tasks. CRP STAFF FOR NCHRP RESEARCH REPORT 1085 Waseem Dekelbab, Deputy Director, Cooperative Research Programs, and Manager, National Cooperative Highway Research Program Michael Brooks, Senior Program Officer Demisha Williams, Senior Program Assistant Natalie Barnes, Director of Publications Heather DiAngelis, Associate Director of Publications NCHRP PROJECT 05-24 PANEL Field of Traffic—Area of Illumination and Visibility John F. White, Lexington, SC (Chair) Douglas M. Burke, Ohio Department of Transportation, Columbus, OH Greg A. Hansen, Tumwater, WA Edward J. Hardiman, California Department of Transportation, Sacramento, CA John Hildreth, Western Carolina University, Cullowhee, NC Jason T. Kruse, Indiana Department of Transportation, Indianapolis, IN Roxane Y. Mukai, Maryland Transportation Authority, Baltimore, MD Martha C. Kapitanov, FHWA Liaison

NCHRP Research Report 1085 presents proposed guidelines for vehicle and equipment color, marking, and lighting practices. Static and dynamic tests were conducted to measure the effects of alternative vehicle marking and warning light treatments on driver perception of workers on foot and of moving work vehicles fitted with the treatments. Testing was also conducted to measure the effects of the alternative treatments on driver lane choice and speed. These guidelines will particularly benefit state department of transportation (DOT) operations personnel by more effectively identifying and communicating their presence to nearby motorists. The timely recognition of work vehicle activity by motorists represents a critical safety consideration within the roadway network. Roadway operations equipment used by state DOTs and transportation agencies for activities such as construction, maintenance, and incident response generally deploys on all types of roadways, during daytime and nighttime hours, and in all weather conditions. To improve motorist and worker safety, equipment must be readily seen and recognized; hence, appropriate colors, retroreflective markings, and warning lights must be provided on the equipment to alert motorists of potentially hazardous situations. Currently, a wide variety of warning lights, vehicle colors, and retro- reflective markings are found on equipment and vehicles used for similar purposes, creating concern that such variety negatively affects the awareness and responsiveness of motorists approaching these vehicles and equipment. Under NCHRP Project 05-24, “Guidelines for Vehicle and Equipment Color, Marking, and Lighting,” the Texas A&M Transportation Institute was asked to develop (1) guide- lines for the selection and application of color, retroreflective markings, and lighting to vehicles and equipment and (2) proposed language for consideration by AASHTO to update the Guidelines for the Selection and Application of Warning Lights on Roadway Operations Equipment. The research team determined that vehicle markings, especially unique ones, assist in nighttime detection of workers on foot; the use of arrayed warning lights, color, and flash speed may increase perception of hazard urgency but also increase distraction and visual discomfort; and irregular flash patterns reduce motorist detection of workers and percep- tion of hazard urgency. NCHRP Research Report 1085 describes the entire research effort and includes four appendices: • Appendix A: Prioritization of Vehicle Marking and Warning Light Attributes • Appendix B: Daytime Static Closed-Course Study Experimental Design and Statistical Analyses F O R E W O R D By Michael Brooks Staff Officer Transportation Research Board

• Appendix C: Nighttime Static Closed-Course Study Experimental Design and Statistical Analyses • Appendix D: Dynamic Closed-Course Study Experimental Design and Statistical Analyses NCHRP Research Report 1085 is accompanied by a slide presentation summarizing the project and a technical memorandum outlining potential implementation avenues for state DOTs and other transportation agencies. These materials are available on the National Academies Press website (nap.nationalacademies.org) and can be found by searching for NCHRP Research Report 1085: Development of Guidelines for Vehicle and Equipment Marking and Lighting. Finally, the proposed language for consideration by AASHTO, “Proposed Updated Language: AASHTO Guidelines for the Selection and Application of Vehicle Markings and Warning Lights on Roadway Operations Vehicles and Equipment,” is available for download at https://apps.trb.org/cmsfeed/TRBNetProjectDisplay.asp ?ProjectID=4359.

1 Summary 7 Chapter 1 Background 7 Introduction 7 Project Objective 7 Summary of Previous Research 14 Organization of the Report 15 Chapter 2 Prioritization of Study Attributes 15 Description of the Prioritization Process 16 Prioritization Results 19 Chapter 3 Static Closed-Course Studies 19 Overview 19 Daytime Studies of Vehicle Marking Alternatives 25 Nighttime Studies of Warning Light Attributes With and Without Vehicle Markings 40 Discussion of Vehicle Marking and Warning Light Attributes 43 Chapter 4 Dynamic Closed-Course Studies 43 Overview 44 Study Methodology 46 Results 54 Discussion 56 Chapter 5 Field Evaluation of Warning Light Treatments 56 Overview 57 Study Methodology 57 Results 60 Chapter 6 Conclusions and Proposed Guidelines 60 Conclusions 62 Proposed Guidelines 67 References A-1 Appendix A Prioritization of Vehicle Marking and Warning Light Attributes B-1 Appendix B Daytime Static Closed-Course Study Experimental Design and Statistical Analyses C O N T E N T S

C-1 Appendix C Nighttime Static Closed-Course Study Experimental Design and Statistical Analyses D-1 Appendix D Dynamic Closed-Course Study Experimental Design and Statistical Analyses Note: Photographs, figures, and tables in this report may have been converted from color to grayscale for printing. The electronic version of the report (posted on the web at nap.nationalacademies.org) retains the color versions.