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Interpretation ID: 77-3.47

TYPE: INTERPRETATION-NHTSA

DATE: 08/10/77

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

TO: Blue Bird Body Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your June 29, 1977, letter asking whether states are preempted from regulating minimum seat spacing in school buses by Standard No. 222, School Bus Passenger Seating and Crash Protection, which regulates maximum seat spacing.

The National Traffic and Motor Vehicle Safety Act provides in Section 103(d):

Whenever a Federal motor vehicle safety standard under this subchapter is in effect, no State or political subdivision of a State shall have any authority either to establish, or to continue in effect, with respect to any motor vehicle or item of motor vehicle equipment any safety standard applicable to the same aspect of performance of such vehicle or item of equipment which is not identical to the Federal standard. Nothing in this section shall be construed to prevent the Federal Government or the government of any State or political subdivision thereof from establishing a safety requirement applicable to motor vehicles or motor vehicle equipment procured for its own use if such requirement imposes a higher standard of performance than that required to comply with the otherwise applicable Federal standard.

Section 103(d) has the effect of preempting safety standards of the states and their political subdivisions unless they are identical to applicable Federal safety standards that regulate the same aspect of vehicle or equipment performance. The second sentence of the section clarifies that the limitation on safety regulations of general applicability does not prevent governmental entities from specifying additional safety features in vehicles purchased for their own use. The second sentence does not, however, permit these governmental entities to specify safety features that prevent the vehicle or equipment from complying with applicable safety standards.

The state regulations to which you refer in your letter would mandate minimum seat spacing in school buses. Although the requirement of the National Highway Traffic Safety Administration (NHTSA) regulates maximum seat spacing and the state requirements regulate minimum spacing, the regulated aspect of performance is seat spacing. Therefore, it is the NHTSA's opinion that state standards applicable to all school buses concerning minimum seat spacing regulate the same aspect of performance as the Federal standard and would be preempted to the extent that they are not identical with the Federal standard. Section 103(d) would not prevent a state from requiring minimum seat spacing in buses procured for its own use as long as the maximum seat spacing of 20 inches is not violated.

The agency will try to disseminate this opinion to the states as broadly as possible. If you receive further state inquiries on this subject, you should refer them to this office.

SINCERELY,

BLUE BIRD BODY COMPANY

June 29, 1977

Joseph J. Levin, Jr. Chief Counsel National Highway Traffic Safety Admin.

The purpose of this letter is to seek clarification regarding the seat spacing requirements of FMVSS 222 vs the seat spacing specifications which have been or are in the process of being adopted by the states.

FMVSS 222 specifies a maximum seat spacing of 20 inches in S5.2.1 measured from the SRP forward to the rear surface of the next seat or barrier.

Some states have adopted, or are in the process of adopting, minimum knee space dimensions from the front of a seat back measured forward to the back of the next seat back. As might be expected, in the specifications which have been adopted so far, there is a lack of uniformity. For example, one specification calls for "a minimum of 24 inches knee space measured horizontally at the seat cushion level at the transverse center line of the seat." This requires 24 inches knee space in the area of the seat back which is recessed for knees but allows less than 24" around the periphery of the seat frame. Another specification requires "24 inches minimum knee space measured across the full width of the seat back." With the latter specification, using a seat back pad recessed in the knee area, the 20 inches maximum spacing requirement of S5.2.1 can easily be exceeded in the recessed area when seats are positioned to get at least 24 inches knee space at the closet point between two seats.

The following is exerpted from the preamble to FMVSS 222 published in the Federal Register of January 27, 1976.

"Section 103(d) of the National Traffic and Motor Vehicle Safety Act provides in part:

(d) Whenever a Federal motor vehicle safety standard is in effect, no State or political subdivision of a State shall have any authority either to establish or continue in effect, with respect to any motor vehicle or item of motor vehicle equipment any safety standard applicable to the same aspect of performance of such vehicle or item of equipment which is not identical to the Federal standard.

It is the opinion of the NHTSA that any State requirement relating to seat spacing, other than one identical to the Federal requirement for maximum spacing of 20 inches from the SRP, is preempted under @@ 103(d), 15 U.S.C. 1392 (d)."

Based on this discussion it is our understanding that states are preempted from adopting any school bus seat spacing specification which differs in any way from the requirements of FMVSS 222; i.e. a maximum of 20 inches from the SRP.

Is this understanding correct? If so, we believe it would be helpful if the NHTSA published a bulletin to this effect to the states. This would prevent the adoption of specifications by the states which conflict with FMVSS 222.

Please be assured there is considerable current activity in this area by the states and a solution to this dilemma is urgently needed.

Your early reply will be greatly appreciated.

Thank you.

W. G. Milby Manager, Engineering Services