Marking DOT-Regulated Trucks and Trailers – Trucks that exceed 10,000 pounds and that are over 80 inches wide must mark their trailers with 2″ wide DOT C2 reflective tape that alternates white and red.. A 6/6 (6″ red and 6″ white) or a 7/11 (7″ white and 11″ red) pattern can be used. 50% of each side must be covered. (even distribution) In the rear, two horizontal red and white strips must be used in the lower rear and an inverted L using solid white must mark the top corners of the trailer. This outlines the back of the rig.
(This is a synopisis of the Federal regulation regarding DOT regulated truck marking. For a word for word copy of the law you can refer to the actual FMCSA document) In summary, to help reduce the incidence of motorists crashing into the rear or sides of tractor-trailers at nighttime and under other conditions of reduced visibility, the FMCSA has set up regulations requiring the use of conspicuity (reflective tape) materials on trailers and the rear of truck tractors. Accidents are reduced by over 40% when these markings are present.
In 1992, the National Highway Traffic Safety Administration or NHTSA published a final ruling requiring that trailers manufactured on or after December 1, 1993, which have an overall width of 80 inches or more and a gross vehicle weight rating (GVWR) of more than 10,000 pounds, (except for pole trailers and trailers designed only for living or office use) be marked on the sides and rear with a means for making them more visible on the road. The NHTSA ruling allows trailer manufacturers to install either red and white retro reflective tape or sheeting or reflex reflectors. This tape is commonly referred to as “DOT C2 reflective tape” which is marked for easy identification.
Locations for Conspicuity Treatment
The following paragraphs describe where the conspicuity treatments need to be located on trailers. An image is provided at the bottom of this page.
2″ wide red and white (silver) DOT C2 retro reflective sheeting must be applied to both sides of the trailer or semitrailer. Each strip of retroreflective sheeting has to be positioned as horizontally as practical, beginning and ending as close to the front and rear as practical. Conspicuity treatment is not required to be continuous, however, the sum of the length of all of the segments must be at least half of the length of the trailer and the spaces between the segments of the strip must be distributed as evenly as possible. The centerline for each strip of retroreflective sheeting (or reflex reflector) must be between 15 inches and 60 inches above the road surface when measured with the trailer empty or unladen, or as close as practical to this area. If necessary to clear rivet heads or other similar obstructions, 50 mm (2 inches) wide retroreflective sheeting may be separated into two 25 mm (1 inch) wide strips of the same length and color, separated by a space of not more than 25 mm (1 inch).
Lower rear area of the Trailer
The rear of each trailer and semitrailer must be equipped with retro reflective sheeting (or reflex reflectors). Each strip of retro-reflective sheeting (or reflex reflector) must be positioned as horizontally as possible, extending across the full width of the trailer, beginning and ending as close to the extreme edges as possible. The centerline for each of the strips of retro-reflective sheeting (or each reflex reflector) must be between 375 mm (15 inches) and 1,525 mm (60 inches) above the road surface when measured with the trailer empty or unladen, or as close as practical to this area.
Upper rear area of the Trailer
Two sets of white strips of retro reflective sheeting (or reflex reflectors), each pair consisting of strips 12 inches long, must be positioned as an inverted L on the right and left upper corners of the rear of the body of each trailer and semitrailer, as close as possible to the top of the trailer and as far apart as practicable. If the perimeter of the body, as viewed from the rear, is not square or rectangular, the conspicuity treatments may be applied along the perimeter, as close as practicable to the uppermost and outermost areas of the rear of the body on the left and right sides.
Rear of Truck
On August 8, 1996, the NHTSA published a final rule requiring that semi trucks manufactured on or after July 1, 1997, be equipped with red-and-white retroreflective material similar to that required on the rear of the trailers they tow to increase nighttime conspicuity. Manufacturers may choose either retroreflective sheeting or reflex reflectors. In the case of truck tractors delivered with a temporary mudflap arrangement rather than permanent equipment, the requirement for retroreflective material near the top of the mudflap may be satisfied with material carried by the temporary mudflap brackets that are transferable to the permanent mudflap system. Retroreflective material is also required near the top of the cab in a pattern similar to that used on trailers.