Interpretation ID: nht91-2.19

DATE: March 8, 1991

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: A. Kling -- Hamadbik, Ltd.

TITLE: None

ATTACHMT: Attached to letter dated 10-12-90 from A. Kling to U.S. Dept of Transport, NHTSA (OCC 5696)

TEXT:

This responds to your inquiry about the color coding requirements in section S5.1.14 of Federal motor vehicle safety standard No. 116, Motor vehicle brake fluids. (49 CFR 571.116). After noting that DOT 3 and DOT 4 brake fluid must be colorless to amber, you asked what is the color coding range for amber. As explained below, the agency has decided not to specify a numerical or chromatic "range" for the color coding requirements. Instead, the appropriate method for determining compliance to the color coding requirements is through visual inspection.

The purpose of the color coding requirements is to permit easy identification of fluids before they are placed in a vehicle, in order to prevent the mixing of an incompatible fluid in a braking system. At one time, the National Highway Traffic Safety Administration (NHTSA) had proposed color requirements defined in terms of millimicrons. (38 FR 32142, November 21, 1973). However, when the agency later determined that visual inspection for color compliance was adequate, the proposed wavelength bands were deleted. (39 FR 30353, August 22, 1974)

In a subsequent notice, the agency explained that

The specifications for fluid colors are intended to refer to color ranges as generally interpreted in daylight by persons of normal color vision. No color coordinates are proposed, since the fluids may change color in storage or in use (without detriment to the performance of the fluids). (40 FR 56928, December 5, 1975)

Thus, the generally interpreted meaning for "amber" (which is defined as "yellowish-brown" by the Random House Dictionary of the English Language) should be used to determine if a brake fluid complies with the color coding requirements for DOT 3 and DOT 4 brake fluid.

I hope this information is helpful. If you have any further questions, please feel free to contact Marvin Shaw of my staff at this address or by telephone at (202) 366-2992.