Interpretation ID: nht90-1.29

TYPE: INTERPRETATION-NHTSA

DATE: 01/29/90

FROM: TIMOTHY A. KELLY -- SALEM VENT INTERNATIONAL, INC.

TO: DAVID A. GREENBURG -- NHTSA CHIEF COUNSEL

TITLE: SALEM BUS VENTILATOR/ESCAPE HATCH - FMVSS 217

ATTACHMT: ATTACHED TO LETTER DATED 05/30/90; FROM STEPHEN P WOOD -- NHTSA TO TIMOTHY A. KELLY; REDBOOK A35; STANDARD 217; LETTER DATED 01/29/90, FROM TIMOTHY A. KELLY TO DAVID A. GREENBURG -- NHTSA; RE SALEM BUS VENTILATOR/ESCAPE HATCH - FMVSS 217; OCC 4 382

TEXT: Pursuant to our meeting of Thursday, January 25, 1990, I respectfully request a written opinion on the following questions regarding FMVSS 217.

1. Size of Escape Hatch: The only size specification mentioned is that the hatch must accomodate an ellipsoid with a major axis of 20" and a minor axis of 13" pushed horizontally through the escape hatch opening.

Is this correct?

2. Application of Specification: A. FMVSS 217 does not address the use of escape hatches/ventilators in the roof of school busses.

B. FMVSS 217 does address the use of an escape hatch/ventilator in the roof of busses other than school busses, and further states that if such a device is used (and it conforms to the ellipsoid spec) then a rear exit door may be deleted on vehicles other than school busses.

Are A and B above correct?

3. Further Possible Deletions: If the non-school bus manufacturer applies more than one roof escape hatch/ventilator, do any further deletions (other than the rear exit door) accrue to the manufacturer under FMVSS 217. My reading shows that no furth er deletions are available to the manufacturer and that more than one escape hatch/ventilator simply serves the function of additional roof top ventilation.

Is the above correct?

Thank you for your prompt attention to these questions - I will await your response.

Sincerely,

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