Standards for Reflective Traffic Posts
Reflective traffic posts must meet standards set by the MUTCD. This post will examine and summarize these guidelines. Please note that this is a high-level introduction to the topic. Detailed information is available in table 2A-3 of the MUTCD current edition.
Everyday practicalities prohibit public agencies from devoting all of their resources to testing reflective traffic posts. For this reason, the Department of Transportation understands that a small number of signs may fail to meet retroreflectivity standards at any given time. This is acceptable, as long as the agency is making a conscientious effort to maintain its signage overall. Local authorities are also free to use whatever maintenance methods work best for them. That being said, the MUTCD does prescribe five ways of maintaining acceptable levels of retroreflectivity. These are:
- Nighttime visual inspections. With this method, a trained sign inspector who is at least 60 years old conducts appraisals of individual signs after dark.
- Reflectometer method. This approach uses a device known as a reflectometer to gauge sign condition.
- Expected sign life method. When a new sign is issued, its manufacturers specify its expected lifespan. Signage is automatically replaced after this period is exceeded.
- Blanket replacement method. This method simply replaces all signs in a given area on a regular basis without checking for individual retroreflectivity.
- Control sign method. The agency chooses specific signs to act as representative samples of the entire signage population. When these products degrade beyond acceptable levels, workers replace all signs in the area.
The MUTCD allows for local authorities to develop their own methods in lieu of choosing one of the above five. These techniques must be based upon sound engineering principles and approved after a suitable evaluation.
Reflective traffic posts are an irreplaceable part of any public safety department's toolkit. Using the steps outlined in this post to evaluate and replace these products will help to ensure the safety of all who use our nation's roads system.