For those questioning legality, this may help "shed some light" on the subject, from NHTSA:
Dear Mr. Hodson:
Your letter of December 16, 1999, addressed to Ms. Nancy McFadden, the General Counsel of the Department of Transportation, has been forwarded to this Office for reply. The National Highway Traffic Safety Administration (NHTSA) is the component of the Department responsible for issuing, interpreting, and enforcing the Federal motor vehicle safety standards. I am sorry that our response to your letter has been delayed.
You relate that a client of yours was charged with operating a motor vehicle with improper headlamps, specifically that the headlamp bulbs have a blue tint to them. The bulbs are replacement bulbs, and were installed by the previous owner of the vehicle. Your review of Federal Motor Vehicle Safety Standard No. 108 Lamps, Reflective Devices and Associated Equipment has led you to conclude that the only permissible colors for headlamps are white and yellow. Yet you understand that some cars have this color of headlamp as original equipment, and you report seeing replacement headlamps, with a similar tint, that are stamped DOT "which presumably reflects approval by your agency," and packaging stating they are legal in all states.
When we revise Standard No. 108 in the near future, we will clearly state that the color of headlamps must be white. The interpretation I am providing, of course, is for the standard as it is presently written. Paragraph S7 of Standard No. 108 sets forth the requirements for headlamps. In various places, S7 specifies that headlamps must meet Society of Automotive Engineers (SAE) J1383 APR85. This refers to SAE Recommended Practice J1383 APR 85 "Performance Requirements for Motor Vehicle Headlamps." Of particular interest to you will be the provisions of S7.5 of Standard No. 108 covering replaceable bulb headlamps, the type used by your client. S7.5(c) in pertinent part requires replaceable bulb headlamps to meet "performance requirements of section 5.1.4 of SAE J1383 APR85." This version of SAE J1383 appears in the SAE Handbooks for the years 1986 through 1990 when J1383 APR85 was revised. Section 5.1.4 of SAE J1383 APR85 states that "The color of the headlamp shall be white as specified in SAE J578." This refers to SAE Standard J578c, February 1977 "Color Specification for Electric Signal Lighting Devices" (see S5.1.5 of Standard No. 108). This version appeared only in the 1978 SAE Handbook.
SAE J578c defines white by blue, yellow, green, red, and purple boundaries within a chromaticity diagram. Thus, it is possible to design a headlamp that emits a light that approaches the blue boundary and is perceived as having a blue tint but which nevertheless remains within the boundaries that define "white." These headlamps would comply with the color requirements of Standard No. 108. Without an actual test of your client's headlamp bulbs, it is not possible to say whether the color emitted remains within the boundaries of "white."
A headlamp's replaceable light sources themselves, whether new or replacement equipment (see S5.8.1) must meet the requirements of S7.7 of Standard No. 108 and bear the DOT symbol that represents the light source manufacturer's certification that the light source meets all applicable requirements of the standard. Though not specifically stated in S7.7, which contains no reference to 5.1.4 of SAE J1383 APR85, these bulbs obviously must project a white light in order for the headlamps to comply when the bulbs are installed. Thus, we regard the color white as one of the performance requirements of replacement replaceable light sources covered by the DOT certification. That is why you see replacement bulb packages (presumably containing DOT-certified light sources) stating that the bulbs are legal in all states.
Please note that the DOT symbol does not represent our "approval." We have no authority to approve or disapprove motor vehicles or motor vehicle equipment. Under 49 U.S.C. 30115, the manufacturer must certify conformance of its product, and we play no role in the certification process.
If you have any questions, you may refer them to Taylor Vinson of this Office (202-366-5263).
Sincerely,
Frank Seales, Jr.
Chief Counsel
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d.5/4/00
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and I get to replace my headlights. SO now I will be modifying my aftermarket Ranger lights
