Interpretation ID: nht79-3.48

DATE: 06/06/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Wayne Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your May 18, 1979, letter asking to what extent the parallelepiped device required by Standard No. 217, Bus Window Retention and Release, must fit inside a school bus in order to provide the mandated "unobstructed passage."

The agency responded to a request similar to yours in 1976. A copy of that interpretation is included for your information. The essence of that interpretation is that while conducting the test in accordance with S5.4.2.1(a) of the standard, the parallelepiped device must, at a minimum, fit inside a bus so that the device's outside edge is flush with the lower outside edge of the bus body. If your bus complies with this interpretation of the standard, it would be in compliance.

SINCERELY,

Wayne Corporation

May 18, 1979

Joseph Levin, Jr. Chief Counsel U.S. Department of Transportation National Highway Traffic Safety Administration

Dear Mr. Levin:

Section S5.4.2.1(a) of FMVSS 217, Bus Retention and Release, requires that the rear emergency door opening of a school bus be large enough to provide the unobstructed passage of a rectangular parallelepiped.

Will the condition illustrated on the enclosed sketch satisfy this requirement? The following applies to this sketch: The rectangular parallelepiped is of the prescribed dimensions, surface "A" is totally within the outline of the body except for the top portion where the body contour slopes forward. The forward side of the rectangular parallelepiped (the side opposite surface "A") is totally inside of the body and contacts the rearmost surface of the passenger seats.

An early reply will be greatly appreciated.

Robert B. Kurre Director of Engineering

SURFACE 'A'

Wayne Corporation An Indian Head Company Wayne Transportation Division Richmond, Indiana

DATE: 5-11-79

SCHOOL BUS REAR EMERGENCY DOOR OPENING PASSAGE (Graphics omitted)