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Lighting Design
  U.S. Department of Transportation Federal Highway Administration 1200 New Jersey Avenue, SEWashington, DC 20590202-366-4000 Federal Highway Administration Research and Technology Coordinating, Developing, and Delivering Highway Transportation Innovations This report is an archived publication and may contain dated technical, contact, and link information Federal Highway Administration > Publications > Research Publications > Safety > 08053 > Informational Report on Lighting Design for Midblock Crosswalks Publication Number: FHWA-HRT-08-053Date: April 2008 Informational Report on Lighting Design for Midblock Crosswalks PDF Version  (945 KB) PDF files can be viewed with the Acrobat® Reader® Table of Contents Foreword The overall goal of the Federal Highway Administration's (FHWA) Visibility Research Program is to enhance the safety of road users through near-term improvements of visibility on and along roadways. The program also promotes the cost-effective advancement of new practices and technologies to improve visibility.The following document summarizes the results of a series of studies that evaluated the visibility of pedestrians at nonintersection (midblock) crosswalks and provides information on lighting designs that will enhance the ability of drivers to detect those pedestrians. The research documented in FHWA-HRT-08-052 (NTIS publication number PB2008-106431), consisting of both static and dynamic experiments of driver performance, found that a vertical illuminance level in the crosswalk of 20 lx, measured at a height of 1.5 m (5 ft) from the road surface, provided adequate detection distances for most midblock crosswalks. This report will be of interest to traffic engineers, lighting designers, and city, State, and local authorities with responsibility for public safety.Michael F. TrentacosteDirector, Office of SafetyResearch and Development Notice Page 1 of 18Informational Report on Lighting Design for Midblock Crosswalks -FHWA-HRT-08-0533/1/2017  This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document.The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers' names appear in this report only because they are considered essential to the objective of the document. Quality Assurance Statement The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement. Technical Report Documentation Page 1. Report No. FHWA-HRT-08-053 2. Government Accession No.3. Recipient's Catalog No.4. Title and Subtitle Informational Report on Lighting Design for Midblock Crosswalks 5. Report Date  April 2008 6. Performing Organization Code:7. Author(s) Ronald B. Gibbons, Chris Edwards, Brian Williams, and Carl K.  Andersen. 8. Performing Organization Report No.9. Performing Organization Name and Address Virginia Tech Transportation Institute3500 Transportation Research PlazaBlacksburg, VA 24061 10. Work Unit No.11. Contract or Grant No. DTFH61-01-C-00049Task Order #4 12. Sponsoring Agency Name and Address Office of Safety Research and DevelopmentFederal Highway Administration6300 Georgetown PikeMcLean, VA 22101-2296 13. Type of Report and Period Covered Summary Report 14. Sponsoring Agency Code HRDS-05 15. Supplementary Notes Contracting Officer's Technical Representative (COTR): Carl Andersen, HRDS-05 16. Abstract This report provides information on lighting parameters and design criteria that should be considered when installing fixed roadway lighting for midblock crosswalks. The information is based on static and dynamic experiments of driver performance with regard to the detection of pedestrians and surrogates in midblock crosswalks. Experimental condition variables included lamp type (high-pressure sodium and metal halide), vertical illuminance level, color of pedestrian clothing, position of the pedestrians and surrogates in the crosswalk, and the presence of glare. Two additional lighting systems, a Probeam luminaire and ground-installed LEDs, were also evaluated. The research found that a vertical illuminance of 20 lx in the crosswalk, measured at a height of 1.5 m (5 ft) from the road surface, provided adequate detection distances in most circumstances. Although the research was constrained to midblock placements of crosswalks, the report includes a brief discussion of considerations in lighting crosswalks colocated with intersections. 17. Key Words18. Distribution Statement Page 2 of 18Informational Report on Lighting Design for Midblock Crosswalks -FHWA-HRT-08-0533/1/2017  crosswalk, midblock, lighting, lighting design, crosswalk lighting, vertical illuminanceNo restrictions. This document is available through the National Technical Information Service; Springfield, VA 22161. 19. Security Classif. (of this report) Unclassified 20. Security Classif. (of this page) Unclassified 21. No. of Pages 27 22. Price Form DOT F 1700.7 (8-72) Reproduction of completed page authorized. Metric Conversion Chart TABLE OF CONTENTS Chapter 1-Introduction BackgroundPurpose Chapter 2-Definitions Pedestrian Visibility Visibility Concepts IlluminanceVertical IlluminanceLuminanceDiffuse ReflectionContrastVisibility LevelContrast Polarity and Contrast VarianceVisual Background Chapter 3-Crosswalk Lighting Design Considerations Vertical Illuminance Luminaire SelectionLuminaire PlacementCrosswalk PlacementOther Lighting Considerations GlareLamp TypeCrosswalks at Intersections   Page 3 of 18Informational Report on Lighting Design for Midblock Crosswalks -FHWA-HRT-08-0533/1/2017  High Ambient Light LocationsChapter 4-Research Findings References LIST OF FIGURES Figure 1. Drawing. Vertical illuminance components.Figure 2. Equation. Vertical illuminance ( E  Vert  ) at a height of 1.5 m (5 ft).Figure 3. Equation. Luminance of a diffusely reflecting surface.Figure 4. Equation. Weber Contrast.Figure 5. Equation. Weber Contrast (modified).Figure 6. Equation. Visibility level (VL).Figure 7. Photograph. Contrast of dark-clothed and light-clothed pedestrians.Figure 8. Photograph. Visual background for a pedestrian at 61 m (200 ft) and at 305 m (1,000 ft) from a vehicle.Figure 9. Plot. Vertical illuminance plot for a 250-W HPS flat lens cobra-head-style luminaire mounted at 8.5 m (28 ft)Figure 10. Plot. Vertical illuminance plot for a 250-W HPS flat lens cobra-head-style luminaire mounted at 10 m (33 ft).Figure 11. Drawing. Traditional midblock crosswalk lighting layout.Figure 12. Drawing. New design for midblock crosswalk lighting layout.Figure 13. Drawing. Traditional intersection lighting layout.Figure 14. Drawing. New design for intersection lighting layout for crosswalks.Figure 15. Drawing. New design for wide roadway intersection lightinglayout for crosswalks. LIST OF ACRONYMS AND ABBREVIATIONS General Terms  ANSI/IESNA RP-8 America n National Standard Practice for Roadway LightingHPS high-pressure sodium (lamp)MHmetal halide (lamp) Measurements visual angle (subtended by an object)cd/m 2 candela per square meter ftfeetfc footcandlefLfootlambert   Page 4 of 18Informational Report on Lighting Design for Midblock Crosswalks -FHWA-HRT-08-0533/1/2017
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