Mr. Robert L. Douglas
Director of Product Integrity
751 South Harkrider
Conway, AR 72032
Dear Mr. Douglas:
This responds to your request for an interpretation of a provision in Federal Motor Vehicle Safety Standard (FMVSS) No. 217, Bus emergency exits and window retention and release. You wish to know whether the provision at S220.127.116.11(a)(4), “No two side emergency exit doors shall be located, in whole or in part, within the same post and roof bow panel space” applies only to side emergency exit doors located on the same side of the bus. The answer is that this restriction applies to all side emergency exit doors located “within the same post and roof bow panel space,” including those on the left and right sides of the bus.
You believe that the restriction should not apply to emergency exit doors located on opposite sides of the bus from each other. You do not believe that the structural integrity is compromised when the doors are mounted on opposite sides of the bus and in the same section.
We have considered your suggestion but conclude that S18.104.22.168(a)(4) also applies to side emergency exit doors located on the opposite sides of the bus. The issue was discussed and decided in a rulemaking proceeding. A notice of proposed rulemaking (NPRM) on S22.214.171.124(4)(under Option B)(March 15, 1991 (56 FR 11153, at 11163)) did not propose to restrict side emergency exit doors from being located, in whole or in part, within the same post and roof bow panel space. In commenting on the NPRM, Thomas Built Buses stated that the left and right side emergency exit doors should not be within the same post and roof bow panel space. In the final rule, the National Highway Traffic Safety Administration adopted Thomas Built’s recommended language at S126.96.36.199(a)(4). Thus, S188.8.131.52(a)(4) was specifically adopted with the intent to exclude left and right side emergency exit doors from being “within the same post and roof bow panel space.”
If you have any further questions, please feel free to contact Dorothy Nakama of my staff at this address or at (202) 366-2992.