Search Interpretations

09-008774 223

Mr. S. Lafferty

Manager, Engineering


10321 Greenleaf Avenue

Santa Fe Springs, CA 90760

Dear Mr. Lafferty:

This responds to your letter asking about Federal Motor Vehicle Safety Standard (FMVSS) No. 223, Rear impact guards, and No. 224, Rear impact protection. Specifically, you ask whether the horizontal member of a rear impact guard may be composed of multiple pieces, as long as the guard passes the requirements of FMVSS No. 223 and FMVSS

No. 224. Our answer is yes.

By way of background, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue FMVSSs that set performance requirements for new motor vehicles and items of motor vehicle equipment (see 49 U.S.C. Chapter 301). NHTSA does not provide approvals of motor vehicles or motor vehicle equipment.  Instead, manufacturers are required to self-certify that their products conform to all applicable safety standards that are in effect on the date of manufacture. NHTSA selects a sampling of new vehicles and equipment each year to determine their compliance with applicable FMVSSs.  If our testing or examination reveals an apparent noncompliance, we may require the manufacturer to remedy the noncompliance, and may initiate an enforcement proceeding if necessary to ensure that the manufacturer takes appropriate action. NHTSA also investigates safety-related defects.

The following is our interpretation of the FMVSSs based on the description in your letter.

FMVSS No. 223 applies to rear impact guards as items of motor vehicle equipment. Nothing in the standard requires the horizontal member to be composed of a single piece. S5.1 of the standard specifies that the horizontal member of each guard, when viewed from the rear as it would be installed on a trailershall have a vertical height of at least 100 [millimeters (mm)] at each point across the guard width. If your guard is composed of multiple pieces, each horizontal member must have a vertical height of at least 100 mm at each point. S5.2 of the standard specifies strength and energy absorption requirements at test locations P1, P2, and P3. As long as your guard meets S5.2 at P1, P2, and P3 when tested according to S6 of the standard, the horizontal member may be composed of multiple pieces.

FMVSS No. 224 applies to trailers and semitrailers with a gross vehicle weight rating of 10,000 pounds or more. This standard requires the vehicles to be equipped with a rear impact guard that is certified as meeting Standard No. 223. We do not interpret FMVSS No. 224 to require the horizontal member of the guard to be composed of a single piece. If the vehicle can meet the requirements in the standard regarding the guards width, height and rear surface location, the horizontal member of the guard may be composed of multiple pieces.

If you have any further questions, please contact Deirdre Fujita of my staff at (202) 366-2992.

Sincerely yours,

O. Kevin Vincent

Chief Counsel

Dated: 5/26/2010