June 1 marked the deadline for retrofitting trailers with red and white reflective tape or reflex reflectors. Fleets that voluntarily fitted older trailers (pre-1993) with tape that isn't red and white are exempt; they can use this tape until June 1, 2009.
As the retrofit deadline neared, NHTSA released research showing that use of the tape does cut down on crashes, especially in very dark conditions. Tape reduces side and rear impacts into heavy trailers by 29% under various poor-visibility categories, including “dark-not-lighted,” “dark-lighted,” “dawn” and “dusk.” In “dark-not-lighted” conditions, the lowest light category, tape reduced crashes by 41%. It did not significantly reduce crashes during daylight.
The study showed that the tape was most effective when the impacting driver was 15 to 50 years old, a reduction of 44%, compared to drivers over 50, where accidents were down 20%. One explanation is that older drivers are less able to see and react to the reflecting tape.