• Trailers and semitrailers with a GVWR of 10,000 pounds or more, and manufactured on or after January 26, 1998, must be equipped with (or have installed) a rear impact guard that meets FMVSS requirements in effect at the time the vehicle was manufactured.
• Specific requirements govern the height, width, distance from the ground, surface area, certification, and labeling of rear impact guards.
• The rear impact guard requirements do not apply to pole trailers, pulpwood trailers, low chassis vehicles, special purpose vehicles, wheels back vehicles, and trailers towed in driveaway-towaway operations.

The rear end protection requirements (the rear bumper requirements) for trailers and semitrailers vary based on vehicle type and year of manufacture. The regulations state the required size and location of the bumper, and the associated National Highway Traffic Safety Administration (NHTSA) regulations (571.223 and 224), include the energy absorption and certification labeling requirements. (393.86).

Vehicles manufactured on or after January 26, 1998

Trailers and semitrailers with a gross vehicle weight rating (GVWR) of 10,000 pounds or more, and manufactured on or after January 26, 1998, must be equipped with a rear impact guard that meets the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 223 (571.223) in effect at the time the vehicle was manufactured. When the rear impact guard is installed on the trailer or semitrailer, the vehicle must, at a minimum, meet the requirements of FMVSS No. 224 (571.224) in effect at the time the vehicle was manufactured. (393.86(a))

The rear impact guard must also meet these requirements:

• Impact guard width — Must extend to within four inches of the side extremities of the vehicle, but not beyond the side extremity of the vehicle.
• Impact guard height — The vertical distance between the bottom edge of the guard and the ground must not exceed 22 inches.
• Guard rear surface — At any height 22 inches or more above the ground, the rearmost surface guard must be within 12 inches of the rear extremity of the vehicle. Theguard, however, may extend beyond the rear extremity of the vehicle.
• Cross-sectional vertical height — The horizontal member of each guard must have a cross sectional vertical height of at least 3.94 inches at any point across the guard width.
• Certification and labeling — Each rear impact guard must be permanently marked or labeled on the forward-facing or rearward-facing surface of the horizontal member of the guard, 12 inches in from the right end of the guard. The certification label must contain:
  • The impact guard manufacturer’s name and address,
  • The month and year that the guard was manufactured, and
  • The letters “DOT”, constituting a certification by the guard manufacturer that the guard conforms to all requirements of FMVSS No. 223.

Exceptions: These general rear impact guard requirements do not apply to pole trailers, pulpwood trailers, low chassis vehicles, special purpose vehicles, wheels back vehicles, road construction controlled horizontal discharge trailers, and trailers towed in driveaway-towaway operations. (393.86(a))

Vehicles manufactured after December 31, 1952

The regulations governing rear impact guards for motor vehicles manufactured after December 31, 1952 (except trailer or semitrailers manufactured on or after January 26, 1998) are found in 393.86(b).