MGA Research Corporation
900 Mandoline Street
Madison Heights, MI 48071
Dear Ms. Rychlewski:
This responds to your letter of June 7, 1995, to the National Highway Traffic Safety Administration (NHTSA), requesting an interpretation of whether a vehicle can be certified as meeting the seat back requirements in S3.2 of Federal Motor Vehicle Safety Standard (FMVSS) No. 201, Occupant Protection in Interior Impact, based on the results of a particular test. The vehicle is equipped with a seat with an inertial latch on the recliner. In order to keep the seat from folding forward during the test procedure specified in FMVSS No. 201, you welded the inertial latch to conduct the test.
In past agency interpretation of the safety standards, NHTSA has stated that if (1) there are two or more possible conditions under which a compliance test may be conducted (e.g., whether an inertial lock is engaged or not); (2) the standard does not specify which test condition is to be used, and (3) the language of the standard as a whole and the standard's purpose do not imply a limit that would make one of those conditions inappropriate, there is a presumption that the requirements have to be met under all test conditions.
The intent of FMVSS No. 201 is to minimize injuries caused by an occupant striking interior components during a crash. Because inertial latches are intended to lock during a crash, NHTSA believes that testing with the inertial latch engaged most closely indicates the protection offered to an occupant during a crash. Therefore, NHTSA would test a vehicle seat back on a seat with an inertial latch with the latch engaged.
The test procedures in NHTSA standards are the procedures NHTSA will use in compliance testing. While manufacturers are not required to test their products using those procedures, they must ensure that the vehicle would comply when tested by NHTSA. NHTSA could weld the latch as you have done, or could engage
the inertial latch through other means. If you believe that the test you conducted indicates that the seat back will comply when tested by NHTSA with the latch engaged, such a test may be the basis for your certification.
I hope this information has been helpful. If you have any other questions or need additional information, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992.
John Womack Acting Chief Counsel