Interpretation ID: nht78-1.35

DATE: 05/11/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Dr. Arthur Yeager

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your telephone request of March 24, 1978, asking whether the seats in school buses are sufficiently strong to allow the installation of seat belts. You stated that some manufacturers are indicating that they cannot install seat belts because the floors of larger school buses cannot withstand the forces generated by seat belts.

As you indicated, Notice 5 of Docket 73-3 stated that school bus seats should be strong enough to withstand the forces seat belts would impose upon them. This statement was based upon the fact that the seats would be designed to comply with the other force requirements of the standard which would increase the strength of the seats making them capable of withstanding seat belt loads. At the time of that notice, there were special seat belt requirements for seat belts in school buses in the then proposed Standard No. 222. These seat belt requirements would have mandated lower belt load requirements than those found in Standard No. 210 which currently applies to school buses (under 10,000 pounds GVWR). The seats in larger school buses should be sufficiently strong to withstand the former proposed force requirements of Standard No. 222, but they might be incapable of withstanding the belt load requirements of Standard No. 210.

Manufacturers who indicate that the seats or floors of larger buses are not strong enough to install seat belts probably misunderstood the belt requirements for large buses. Seat belts can be installed for passenger seats in larger school buses without complying with any existing seat belt requirements. Seat belts for passenger seats are not required, for example, to comply with Standard No. 210. Therefore, a State would be permitted to establish their own acceptable belt load requirements for these seat belts in large school buses. The National Highway Traffic Safety Administration suggests that States adopt the belt load requirements previously proposed for Standard No. 222. School bus seats currently in production should be sufficiently strong to withstand the former proposed belt load requirements.