Interpretation ID: aiam2636
Director of Engineering
Collins Industries
Inc.
P. O. Box 58
Hutchinson
KS 67501;
Dear Mr. Beach: This responds to your June 23 and July 8, 1977, letters asking severa questions about the effect of Standard No. 222, *School Bus Passenger Seating and Crash Protection*, on the construction of school buses with gross vehicle weight ratings (GVWR) below 10,000 pounds.; You first ask whether there are any seat performance requirements fo the rearmost seat after April 1978. The rear seat has been exempted from the forward and rearward performance requirements of the standard. This exemption was possible since there are no passengers seated behind the rear seat who could impact with it in a crash situation. Therefore, the rear seat may be positioned against the rear panel if it does not protrude into the emergency exit zone.; In a second question, you ask whether the head protection zon requirements (S5.3), as well as the requirements of S5.1.2, S5.1.3, S5.1.4, and S5.1.5, are applicable to buses with GVWRs of 10,000 pounds or less since these buses are required to have seat belts. The answer to your question is yes. Section S5(b) of the standard states that all of the above sections are applicable to buses with GVWRs of 10,000 pounds or less.; In connection with your question concerning the head protection zon requirements, you submitted sketches of the sidewall and roof structure of one of your buses. In that sketch you depict a 50th percentile adult and show the proximity of that adult with the sidewall-roof structure. You question whether a portion of the bus structure above the window is part of the roof structure subject to the head protection zone requirements. The NHTSA has determined that the portion of the interior skin that is depicted by the diagonal line connecting the horizontal roof line to the vertically contoured line representing the sidewall is part of the roof structure and must comply with the requirements of the standard for head protection.; Sincerely, Joseph J. Levin, Jr., Chief Counsel