Interpretation ID: nht76-5.10

DATE: 08/24/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Sheller-Globe Corporation

COPYEE: TRUCK BODY AND EQUIP. ASSOC.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Sheller-Globe's July 7, 1976, request for revision of the requirements of S5.4.2.1 of Standard No. 217, Bus Window Retention and Release, so that passage of the described parallelepiped through the emergency door can be effected with its lower surface several inches above the bus floor. Section 5.4.2.1 requires that the 45-inch dimension of the parallelepiped remain vertical, that the 24-inch dimension remain parallel to the opening, and that the lower surface remain in contact with the floor of the bus at all times.

The three specifications for passage of the parallelepiped through the opening are intended to describe, for the benefit of the manufacturer, how the NHTSA will conduct its compliance testing. These specifications do not represent a requirement that the opening be constructed without a threshold or corner obstructions. As the agency interprets this requirement, minor obstructions that do not necessitate passage of the parallelepiped through the opening more than 1 inch above the floor are not prohibited by this requirement. Thus, in the case you describe, the NHTSA would move the parallelepiped through the opening with its sides vertical and the rear surface parallel to the rear surface of the bus, just above the obstructions, but no more than 1 inch above the bus floor.

SINCERELY,

SHELLER-GLOBE CORPORATION Vehicle Planning and Development Center

July 7, 1976

Administrator National Highway Traffic Safety Administration

Reference: Federal Motor Vehicle Safety Standard 217 - School Bus Emergency Exit Requirements (Docket No. 75-3; Notice 2 - Effective October 26, 1976)

Paragraphs S5.4.2 and S5.4.2.1 of the above referenced safety standard require that the Parallelepiped should be entered into the emergency door opening, keeping the 24 inch dimension (the base of the Parallelepiped) parallel to the opening and the lower surface (the base of the Parallelepiped) in contact with the floor of the bus at all times.

By reducing the seating capacity of the bus, by installing one (1) 26 inch and one (1) 39 inch seat in the rearmost row, the requirement for the 24 inch wide Parallelepiped can be met in Superior School Buses, shown on Drawing No. 4100429, attached. However, also as shown on the attached drawing, the requirement for keeping the lower surface in contact with the floor cannot be met in Superior Buses.

The problem as can be seen on the attached drawing is two-fold, and as follows:

Section B-B, depicts a riser that as installed functions as a part of the emergency door weather sealing arrangement.

View Circle A, depicts a 2.81 inch radius that exists in the two lower corners of the emergency door opening. These radii also serves as a part of the emergency door weather sealing arrangement. Most importantly, these 2.81 inch radii are a part of the emergency door sash and are a part of a major structural member of the bus rearend assembly.

If the Superior Divisions of Sheller-Globe Corporation are required to comply with the exact requirements of Paragraphs S5.4.2 and S5.4.2.1 of the above referenced safety standard, and a major reengineering, redesign and retooling program would be required, in addition, the newly configured rearend assembly would need to be subjected to an extensive real-world evaluation to establish its' structural reliability.

The Superior Divisions of Sheller-Globe Corporation requests that the requirements of Paragraphs S5.4.2 and S5.4.2.1 of the above reference safety standard be rewritten to permit the existence of minor functional components in the emergency door openings such as the "riser" and minor radii as depicted on the attached drawing. It is the opinion of the Super Divisions of Sheller-Globe Corporation that permitted existence of such minor functional components would in no manner obstruct the effective egress of children in schoolbus crash situation.

Your concurrence in the above matter would be appreciated.

George R. Semark - Manager Vehicle Safety Activities