Retroreflective tape is the red and white striping on trailers that glows under headlights at night. Simple as it seems, it’s one of the most effective safety features ever added to large trucks. When the tape is clean and working properly, it helps drivers see trailers earlier and avoid dangerous rear-end crashes.
The problem is, the tape doesn’t stay effective forever. Over time, it fades, gets dirty, and loses its brightness.
Federal rules require trailers to have retroreflective sheeting when they’re manufactured, but there’s no follow-up requirement to check if it still works years down the line.
Recent research shows that more than a third of trailers on the road today have tape that no longer meets minimum brightness standards. In other words, we’re sharing highways with trucks that aren’t as visible as they should be.
In this post, we’ll look at what the research discovered, and why it’s time to start treating retroreflective tape maintenance like the critical safety feature it is.
What is Retroreflective Tape?
Retroreflective tape (also called conspicuity tape) is designed to reflect light directly back toward its source, such as a car’s headlights. It’s the glowing outline you see when your beams hit a trailer in the dark.
Without it, trailers can be almost invisible at night.
The safety benefits are well documented. A study by Morgan (2001) found that trailers with clean, functional reflective tape experienced about a 53% percent reduction in nighttime rear-end crashes. The catch is, it only works when it’s bright enough to be seen.
Not All Tape Reflects the Same
Even high-quality retroreflective tape loses performance over time.
Federal Motor Vehicle Safety Standards (FMVSS 108) and Federal Motor Carrier Safety Regulations (FMCSR 393.11) set minimum brightness levels for new tape, measured in candela per lux per square meter (cd/lux/m²). But once the trailer leaves the factory, there’s no requirement to check that those levels are still being met.
The gap leaves thousands of trailers on the road with tape that no longer provides the protection it was meant for.
How Researchers Put It to the Test
To assess the real-world effectiveness of retroreflective sheeting, researchers conducted a two-part study.
In the first part, they measured tape brightness on 10 trailers using a handheld retro reflectometer. Each strip was tested before and after cleaning to see how much dirt affected its ability to reflect light.
Next, they looked at 191 trailers at DOT inspection stations and truck stops across five states. Using a simplified roadside protocol, they recorded brightness at multiple points on each trailer and compared the results to federal brightness standards (250 and 60 cd/lux/m² for white and red tape respectively).
The goal was twofold: find out how common the problem really is, and see if inspectors could test tape quickly and accurately without needing a full hour to do it.
What They Found About Dirt and Degradation
The results were clear, and a little alarming.
Just cleaning the tape boosted reflectivity by about 25% on average for both red and white strips. Essentially, a trailer that looks fine to the eye may be dangerously dim until the tape is cleaned.
But even after cleaning, many trailers still failed to meet federal brightness standards:
- 34% of white tape was too dim
- 26% of red tape also fell below the required level
These results match earlier studies from the 1980s and 1990s, which also showed that dirt and sunlight slowly wear down the tape’s ability to reflect light. When the tape gets dim, trailers are not only harder to see but can also look farther away than they are.
The Age Factor: Older Trailers Are Worse
As expected, older trailers fared worse.
- Trailers from 1994–1999: 70% had white tape that didn’t meet the standard.
- Trailers built after 2010: Only 5% had dim tape.
- Trailers built before 1993: Surprisingly, these performed slightly better than the mid-90s group, probably because many had newer tape added later to meet updated rules.
The trend is clear. Once trailers age, their reflective tape becomes less effective. Yet federal policy still doesn’t include any trailer lighting requirements to check or replace it over time.
A Faster Way to Inspect
The researchers also tested whether it’s feasible to check reflective tape for trailers without disrupting operations.
The answer was yes.
Instead of measuring every strip of tape, they tested every other one. The simple change cut the inspection time from 85 minutes to just 13 minutes, with almost no drop in accuracy.
The results from the shortened method closely matched the full inspection, with correlation scores above 0.97 for both red and white tape. So, with the right handheld tools, inspectors could quickly and reliably identify trailers with faded tape, without slowing down roadside operations.
Why This Matters for Nighttime Crashes
Rear-end crashes involving large trucks are much more dangerous at night. Research by Sullivan and Flannagan (2003) found they’re eight times more likely in the dark than during the day.
The statistic makes sense when you consider how critical nighttime visibility is. If a driver doesn’t see a truck in time, they can’t brake in time. Also, when you combine highway speeds with a multi-ton vehicle, the outcome is usually catastrophic.
Degraded retroreflective sheeting shortens the window of visibility even further. A driver who might have had three seconds to react may now only have two or even less. The sliver of time can be the difference between a near miss and a fatal crash.
Implications for Crash Reconstruction and Litigation
Crash investigators and attorneys already consider visibility an important factor in nighttime crashes. What the research adds is clear proof that faded or dirty reflective tape is a widespread problem, and one that can now be measured.
If a trailer’s retroreflective tape fails to meet brightness standards, it can directly affect fault and liability. A driver may have had too little time to react, not because they were inattentive, but because the trailer simply wasn’t visible enough.
Tools like Response™ allow analysts to use concrete measurements from the scene. By entering the brightness of the tape, they can calculate how far away the trailer could be seen and how much time the driver had to respond.
Instead of relying on assumptions, reconstructions can now be grounded in science-backed visibility models and real-world measurements.
Why a Maintenance Standard is Overdue
Right now, U.S. regulations treat reflective tape as a one-time requirement. Install it once, and you’re good forever.
The data proves otherwise. More than a third of trailers on the road fail to meet the minimum brightness standard. Millions of drivers are unknowingly at higher risk every time they head out after dark.
Other safety features like brakes, lights, and tires have regular inspection rules. It’s time retroreflective tape maintenance became part of that list.
Final Thoughts
Having reflective tape on a trailer doesn’t mean it’s doing its job. It only protects lives when it’s clean and bright enough to see.
With so many trailers failing to meet the standard, it’s time for policymakers to act. A maintenance requirement for reflective tape would save lives, improve crash investigations, and make highways safer for everyone.
At the Driver Research Institute, we believe road safety should be guided by science, not guesswork. Our tools, like the Response™ software, give investigators, engineers, and policymakers the data they need to understand crashes and prevent them.
If you’re looking to strengthen your crash analysis or see how visibility research can support litigation and safety policy, reach out to us today.
