Interpretation ID: aiam3073
Specifications Engineer
Thomas Built Buses
Inc.
1408 Courtesy Road
P.O. Box 2450
High Point
NC 27261;
Dear Mr. Tydings: This responds to your July 20, 1979, letter asking a questio concerning Standard No. 217, *Bus Window Retention*. You ask whether paragraph S5.4.2.1(a) permits the parallelepiped device to compress the seat cushion when it is inserted in a school bus emergency exit in accordance with the test procedures of the standard. The answer to your question is no.; Paragraph S5.4.2.1(a) states that each rear emergency exit must provid 'an opening large enough to permit unobstructed passage of a rectangular parallelepiped device...' If the parallelepiped device compresses the seat cushion while being inserted in the bus, its passage is not unobstructed as required by the standard. Accordingly, the National Highway Traffic Safety Administration concludes that the device must enter the vehicle without compressing the seat cushion.; Sincerely, Frank Berndt, Chief Counsel