Interpretation ID: nht74-3.31

DATE: 09/06/74

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: General Motors Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your letter of August 14, 1974, requesting an interpretation of Motor Vehicle Safety Standard No. 106-74, Brake Hoses (Docket 1-5, Notice 11, published on June 28, 1974), regarding its applicability to specific hydraulic brake booster hoses used on General Motors products.

As indicated in Notice 11, it is the National Highway Traffic Safety Administration's (NHTSA) intention to exempt from the requirements of the standard hydraulic booster lines subject to a different working environment than brake hose, pending development of special performance requirements for such lines. General Motors' interpretation that the hydraulic booster hoses used in the systems described in your August 14 letter are exerpted from the standard requirements is correct. The system described in your Attachment A is considered to incorporate an accumulator integral with the brake booster assembly. Hence all of the hoses run between the power steering pump and the accumulator (either directly or via the power steering gear) and are accordingly exempted per the Notice 11 preamble. The hoses used in the system described in your Attachment B are exempted by virtue of the provision of redundant booster power by the independent electrohydraulic pump.

A future amendment to FMVSS 106 to eliminate ambiguity in respect to the standard's applicability to hydraulic booster hoses is currently under consideration. Any such amendment will be consistent with the present interpretation.