Nighttime Visibility
![vehicles in traffic at night](https://webarchive.library.unt.edu/web/20081105041034im_/http://safety.fhwa.dot.gov/images/garnish/orange_rain.jpg)
Nighttime visibility of signs and pavement markings provide critical information to drivers at night, help drivers navigate the road during nighttime hours, enhance traffic flow and driver mobility, and promotes safe driving.
Retroreflectivity is the scientific term that describes the ability of a surface to return light back to its source. Retroreflective signs and pavement markings bounce light from vehicle headlights back toward the vehicle and the driver's eyes, making signs and pavement markings visible to the driver.
Signs
- Announcement of Final Rule: Revision 2 of the 2003 Manual on Uniform Traffic Control Devices (MUTCD) was published in the Federal Register on December 21, 2007, and is effective as of January 22, 2008. The final rule provides additional requirements, guidance, clarification, and flexibility in maintaining traffic sign retroreflectivity that is already required by the MUTCD. The minimum retroreflectivity levels and maintenance methods consider changes in the composition of the vehicle population, vehicle headlamp design, and the demographics of drivers. The FHWA expects that the levels and maintenance methods will help to promote safety and mobility on the nation’s streets and highways.
- Frequently Asked Questions
- What has changed due to recent rulemaking for maintaining minimum sign retroreflectivity. [HTML] [PDF - 102KB]
- Flyer: New Sign Retroreflectivity Requirements [HTML] [PDF - 5.66 MB]
- Brochure: Maintaining Traffic Sign Reroreflectivity - 2007 [HTML] [PDF - 198 KB]
- News Article: New Sign Retroreflectivity Requirements [HTML] [PDF - 81.4 KB]
- 15 minute Presentation: New Sign Retro Requirements – [HTML] [PPT - 2.29 MB]
- Contact your local FHWA Division Office for more detailed information.
- Coming soon! Implementation Tool Kit for Small and Medium size Agencies
- Final Rule: Maintaining Sign Retroreflectivity [HTML] [PDF - 261 KB]
- Report: Methods for Maintaining Traffic Sign Retroreflectivity [HTML] [PDF - 683 KB]
- Background: Rulemaking process included a Notice of Proposed Amendment (NPA) and a Supplemental Notice of Proposed Amendment (SNPA) on Sign Retroreflectivity
- Other Sign Retroreflectivity Information:
Pavement Markings
The FHWA has prepared updated background information regarding pavement marking retroreflectivty:
- Report: “Updates to Research on Recommended Minimum Levels for Pavement Markings
- Report: “Preliminary Economic Impacts of Implementing Minimum Levels of Pavement Marking Retroreflectivity” [HTML] [PDF - 464 KB]
- 2007 Workshops: A Summary of the Results From FHWA’s Pavement Marking Retroreflectivity Workshops [HTML] [PDF - 426 KB]
- Other Pavement Marking Information:
Manual on Uniform Traffic Control Devices (MUTCD)
Retroreflectivity General Information
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