Interpretation ID: 1983-2.7

TYPE: INTERPRETATION-NHTSA

DATE: 05/17/83

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Eaton Limited

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your recent letter asking a question concerning Safety Standard No. 106, Brake Hoses. You note that there is an ambiguity in the formula referenced in paragraph S8.3.2(e) of that standard as set forth in the Code of Federal Regulations. Specifically, you ask whether the entire fraction that is specified is multiplied by "100" or whether only the denominator of the fraction is multiplied by "100".

The correct formula is as follows:

(W3-W4) - (W1-W2) / (W1-W2) X 100

The formula as specified in the Code of Federal Regulations should, therefore, include additional brackets around the fraction, separating the fraction from the "X 100" figure. We will notify the Federal Register concerning this error.

I hope this has clarified any misunderstanding you may have had.

Sincerely,

ATTACH.

APRIL 11, 1983

Office of Vehicle Safety Standards, Crash Avoidance Division, National Highway Traffic Safety Administration,

Dear Sirs,

I have been comparing Federal Motor Vehicle Safety Standard number 106-74, Brake Hoses, with the Code of Federal Regulations - Title 49 - S571,106 - Standard 106 - Brake Hoses.

I would draw your attention to paragraph S8.3.2(e) ref calculation of the percentage increase in volume. In 106-74 the formula is given as:-

Percent of increase = (W3-W4) - (W1-W2) / (W1-W2) x 100

In S571,106 the formula is given as:-

Percent of increase = [(W3-W4) - W1-W2)] / (W1-W2) x 100

This could be interpreted as:-

Percent of increase = [(W3-W4) - (W1-W2)] / (W1-W2) x 100

which is not the same as the formula given in 106-74.

This, I believe, could lead to problems. I enclose the appropriate pages from the standards mentioned with the paragraph highlighted in red.

I should be pleased to receive your comments as we are endeavouring to get a potential supplier of hoses to comply with S.571.106.

Yours faithfully,

N. COPE

Standards Engineer -- EATON LIMITED TRUCK COMPONENTS OPERATIONS