The U.S. Department of Transportation's National Highway Traffic Safety Administration (NHTSA) evaluated the effectiveness of retroreflective tape on heavy trailers. Heavy trailers, defined as those 80 inches wide with a Gross Vehicle Weight Rating over 10,000 pounds, must be equipped with retroreflective tape, sheeting, or reflex reflectors since December 1, 1993, to increase visibility to other motorists, especially in dark conditions. The tape, which is red-and-white, is applied to the sides and rear of trailers to make them more conspicuous. The purpose of the tape is to increase visibility, allowing drivers to see trailers in time to avoid collisions. The study analyzed crash data from Florida and Pennsylvania, where state police collected information on crashes involving tractor-trailers. The data included details on whether trailers had retroreflective tape, the light conditions, and the type of crash. The analysis estimated the reduction in side and rear impacts into tape-equipped trailers in dark conditions compared to trailers without tape. The study found that retroreflective tape significantly reduces side and rear impacts into heavy trailers in dark conditions. Specifically, it reduced these impacts by 29 percent overall. The tape was most effective in dark-not-lighted conditions, reducing impacts by 41 percent. In dark-lighted, dawn, and dusk conditions, the tape did not significantly reduce crashes. The tape also did not significantly reduce crashes during daylight. The tape was especially effective in preventing severe crashes, such as those involving injuries. It was more effective in preventing rear impacts than side impacts, though this difference was not consistent in both states. The tape was effective in both clear and rainy/foggy weather conditions. It was especially effective on flatbed trailers, which were difficult to see in the dark before treatment. However, dirt on the tape reduced its effectiveness in rear impacts. The study also found that the tape was effective in reducing crashes involving older trailers, which were being retrofitted with tape before the standard was implemented. Over 50 percent of pre-standard trailers in the study had retroreflective tape. The tape was mostly clean, with only a small percentage being very dirty. The study concluded that retroreflective tape is effective in reducing side and rear impacts into heavy trailers in dark conditions. It is estimated that the tape will save 191 to 350 lives per year, prevent 3,100 to 5,000 injuries per year, and prevent 7,800 crashes per year. The effectiveness of the tape was consistent across different states and conditions, with the most significant reductions in dark-not-lighted conditions. The study also found that the tape was more effective in preventing crashes involving younger drivers.The U.S. Department of Transportation's National Highway Traffic Safety Administration (NHTSA) evaluated the effectiveness of retroreflective tape on heavy trailers. Heavy trailers, defined as those 80 inches wide with a Gross Vehicle Weight Rating over 10,000 pounds, must be equipped with retroreflective tape, sheeting, or reflex reflectors since December 1, 1993, to increase visibility to other motorists, especially in dark conditions. The tape, which is red-and-white, is applied to the sides and rear of trailers to make them more conspicuous. The purpose of the tape is to increase visibility, allowing drivers to see trailers in time to avoid collisions. The study analyzed crash data from Florida and Pennsylvania, where state police collected information on crashes involving tractor-trailers. The data included details on whether trailers had retroreflective tape, the light conditions, and the type of crash. The analysis estimated the reduction in side and rear impacts into tape-equipped trailers in dark conditions compared to trailers without tape. The study found that retroreflective tape significantly reduces side and rear impacts into heavy trailers in dark conditions. Specifically, it reduced these impacts by 29 percent overall. The tape was most effective in dark-not-lighted conditions, reducing impacts by 41 percent. In dark-lighted, dawn, and dusk conditions, the tape did not significantly reduce crashes. The tape also did not significantly reduce crashes during daylight. The tape was especially effective in preventing severe crashes, such as those involving injuries. It was more effective in preventing rear impacts than side impacts, though this difference was not consistent in both states. The tape was effective in both clear and rainy/foggy weather conditions. It was especially effective on flatbed trailers, which were difficult to see in the dark before treatment. However, dirt on the tape reduced its effectiveness in rear impacts. The study also found that the tape was effective in reducing crashes involving older trailers, which were being retrofitted with tape before the standard was implemented. Over 50 percent of pre-standard trailers in the study had retroreflective tape. The tape was mostly clean, with only a small percentage being very dirty. The study concluded that retroreflective tape is effective in reducing side and rear impacts into heavy trailers in dark conditions. It is estimated that the tape will save 191 to 350 lives per year, prevent 3,100 to 5,000 injuries per year, and prevent 7,800 crashes per year. The effectiveness of the tape was consistent across different states and conditions, with the most significant reductions in dark-not-lighted conditions. The study also found that the tape was more effective in preventing crashes involving younger drivers.