U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
Adequately maintained retroreflective signs improve highway safety and prevent roadway departure crashes by bouncing light from vehicle headlights back toward the vehicle and the driver's eyes, making the signs appear brighter and easier to see and read. Because the retroreflective properties of traffic control devices deteriorate over time, highway agencies need to actively manage the maintenance of signs in order to ensure that they are clearly visible at night.
Methods for Maintaining Traffic Sign Retroreflectivity:
This 2007 report prepared by Texas Transportation Institute for the FHWA provides technical guidance on methods for maintaining traffic sign retroreflectivity in accordance with the new Federal rules. [Publication No. FHWA-HRT-08-026]
Maintaining Traffic Sign Retroreflectivity UPDATED!
This 4-page technical brief provides additional information on the sign retroreflectivity maintenance requirements in the MUTCD. This document is referenced in Paragraph 5 of 2009 MUTCD Section 2A.08. [Publication No. FHWA-SA-07-020 (Revised 2013)] No hard copies of this document are currently available from FHWA.
FHWA Guidance Memos on Sign Sheeting Products:
Clarifying Guidance on Application of Daytime Luminance Factors in 23 CFR 655 NEW!
This January 2013 memorandum provides background and guidance on applying the regulations to newer sheeting types.
Recommended Minimum Maintained Retroreflectivity Levels for Blue and Brown Traffic Signs
This April 2012 FHWA memorandum provides information on minimum maintained retroreflectivity levels for white-on-blue signs and white on brown signs. These levels were established through research, but because they were not available during the rulemaking process, it remains the option of agencies to apply the values as the monitor, install and replace signs.
Guidelines for Evaluating Public Interest Findings and Certifications for Retroreflective Sheeting for Traffic Control Signs:
This July 2006 FHWA memorandum provides guidelines to assist practitioners in making informed decisions regarding sign sheeting products.
Sign Sheeting Proprietary Products:
This January 2006 FHWA memorandum addresses issues regarding traffic sign sheeting and regulations concerning sole source requirements.
Guidelines when considering 3M Diamond Grade Cubed PIF Requests
This December 2007 FHWA memorandum determines that more information is needed and a PIF is not approved at this time.
For hard copies of documents with publication numbers, please send a request to firstname.lastname@example.org and include the publication number and title, along with the number of copies and your mailing address and phone number. Requests will be filled based on availability.