FEDERAL HIGHWAY ADMINISTRATION NIGHTTIME VISIBILITY RULES TAKE EFFECT
New nighttime visibility rules have been adopted by the Federal Highway Administration (FHWA) and became effective on January 22, 2008. The final rules provide additional requirements for maintaining traffic sign nighttime visibility by means of “retroreflectivity”. Retroreflectivity describes the efficiency of a material in redirecting light back to its source. Retroreflectivity materials are engineered to redirect a majority of available light back toward the source, giving the sign a brighter appearance at night from the driver’s perspective. Most signs in the U.S. are made with retroreflective sheeting materials, but these materials degrade over time. The new rules are designed to ensure that traffic signs are maintained at a retroreflectivity level that will allow nighttime drivers to see them clearly. Cities must develop and implement a program to maintain retroreflective materials on traffic control signs at certain minimum levels as follows:
- January 2012: A city must implement an assessment or management method that is designed to maintain traffic sign retroreflectivity at or above the minimum levels shown in the new retroreflectivity table.
- January 2015: A city must replace any regulatory, warning, or ground-mounted guides (except street name signs) that are identified by the assessment or management method as failing to meet the minimum retroreflectivity levels.
- January 2018: A city must replace any street name signs and overhead guide signs that are identified by the assessment or management method as failing to meet the minimum retroreflectivity levels.
Under the rules, a city or other public agency would be in compliance with the new retroreflectivity provisions even if there are some individual signs that do not meet the minimum retroreflectivity levels at a particular point in time, as long as the city has a program designed to update traffic signs for retroreflectivity.
Information about the new retroreflectivity rules, including the new retroreflectivity table, can be viewed at the FHWA’s MUTCD website at: http://safety.fhwa.dot.gov/roadway_dept/retro/.
Please contact the TML Legal Department at 512-231-7400 or at legal@tml.org with questions. Sample assessment policies will be linked to as they become available.