Skip to Content

Proposed Rule

Denial of Petition for Rulemaking; Federal Motor Vehicle Safety Standards

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble


National Highway Traffic Safety Administration (NHTSA), Department of Transportation.


Denial of petition for rulemaking.


This document denies the petition submitted by Valeo, an automotive lighting company in Bobigny, France, to amend Federal Motor Vehicle Safety Standard (FMVSS) No. 108, “Lamps, Reflective Devices, and Associated Equipment,” to allow headlamps with upper beam contributors to have horizontal and vertical aiming capabilities that are separate from the lower beam contributors.

Start Further Info


Mr. Chris Flanigan, Office of Rulemaking, NHTSA, 400 Seventh Street, SW., Washington, DC 20590. Mr. Flanigan's telephone number is: (202) 366-4918. His facsimile number is (202) 366-4329.

End Further Info End Preamble Start Supplemental Information


By a letter dated March 2, 2000, Valeo petitioned the agency to allow visually/optically aimable (VOA) headlamps that have upper beam contributors optically combined with lower beam Start Printed Page 68552contributor(s) to have their own horizontal and vertical aiming mechanisms. None of these upper beam contributor(s) would be a lower beam contributor. Additionally Valeo stated that the light-emitting surface of each of these upper beam contributors would be marked “VO.”

Currently, paragraphs S7.8.5.3(5)(c) and (d) of FMVSS No. 108 require that, if the upper beam is combined in a headlamp with a lower beam, the vertical and horizontal aim shall not be changed from the aim set using the procedures set forth for aiming of the lower beam. The effect of this requirement is that, as with previous headlamps that have both a lower and upper beam, aiming the lower beam simultaneously aims the upper beam. As such, the complex headlamp is as easy to aim as a simple one. This promotes correct aim to improve seeing, while minimizing glare.


Proper aim is required to ensure that headlamps installed on motor vehicles fulfill the safety functions required by Federal law. There are three principal methods of aiming headlamps. The first is visual and is done by projecting the beam onto a vertical surface and then adjusting the headlamp to an appropriate position. An observer determines this position. The second is optical and is done by projecting the beam into an optical device that is placed in front of the headlamp and then adjusting the headlamp until the beam conforms to the appropriate parameters. Lamps utilizing these two methods are termed visual/optical aim (VOA) headlamps.

The third method of aim is mechanical and is done without activation of the headlamp. In this case, the proper aim is determined through the use of mechanical equipment, either external to the headlamp housing or provided as part of the headlamp. External mechanical aim was introduced in 1955 by the automotive industry in response to aiming concerns expressed by the States. These concerns were related to the inability of the first two methods to provide accurate and repeatably correct aim at that time.

The ability of motor vehicle headlamps to be mechanically aimed has been a requirement of FMVSS No. 108 from its effective date of January 1, 1968. Mechanical aiming was necessary because accurate and reliable visual or optical aim of the lower beam pattern in use in the United States at that time was difficult to achieve. Sealed beam headlamps, the only type permitted until 1983, are required to have one of four aiming pad patterns on the lens for mechanical aiming. These patterns consist of three raised aiming pads arranged as a triangle at specified points on the lens that create a precise interface between the headlamp and a mechanical aiming device attached to the headlamp during the aiming verification process. The mechanical aiming device provides information so that the aiming planes of the headlamps on each side of the vehicle can be adjusted to be parallel with each other and perpendicular to the road surface. Because a headlamp's beam pattern is designed to be correctly aimed when the aiming plane is oriented as stated, the beam pattern can be accurately and repeatably aimed without the need for illuminating the headlamp.

With the advent of replaceable bulb headlamps in 1983, restrictions on the size and shape of headlamps were no longer required. While two additional configurations of mechanical aiming pads were permitted, not all headlamp designs could accommodate them. In response to this problem, the agency has allowed vehicle headlamp aiming devices (VHAD) since June 8, 1989. VHAD is an alternative method of mechanical aim that is not dependent upon an externally applied mechanical device. It is accomplished by mechanical aiming equipment on the vehicle itself.

As a consequence, the vehicle industry requested that the agency allow VOA headlamps, provided that significant visual cues in the beam pattern were added to assure accuracy. Subsequently, VOA headlamps became part of FMVSS No. 108, and headlamps meeting new beam pattern photometric requirements were developed. These headlamps have a beam pattern that is relatively insensitive to modest horizontal misaim. VOA headlamps were allowed based on comments to the agency that vehicles could be built with such close tolerances that no horizontal aim adjustment was necessary. Additionally, no useful visual cue for horizontal aiming exists. Consequently, because no visual cue was available for the purpose of horizontal aiming, the agency did not permit any horizontal movement of VOA headlamps. The lamp is essentially correctly aimed, horizontally, as installed. As an alternative, horizontal-aiming VHADs were permitted on VOA headlamps to meet European specifications that require both a horizontal and vertical aim adjustment. Thus, to be sold in both the European and U.S. markets, a headlamp needs both a horizontal and vertical aiming screw. A VOA headlamp intended for use only in the U.S. market need only have the vertical one.

Petitioner's Rationale

Valeo asserted that the rationale for the current requirements was derived in the 1980s when headlamps with replaceable light sources were first introduced into Federal regulations. At that time, headlamps were not as large as today. Because the majority of these lamps had a flat, rectangular appearance, there were few aspect-related issues. However, today's headlamps have many cavities and are more contoured to the shape of the vehicle body. They also can have somewhat vertical shapes. Because of these characteristics, the orientation of the upper and lower beam contributors becomes more critical to the appearance of the vehicle. On the VOA lamps Valeo is contemplating, the cavities producing the lower beam have vertical aiming capability. However, they would have no horizontal aiming capability unless it is of the VHAD type. When the vertical aim on the lower beam is adjusted, unsightly gaps can be generated in the area between the headlamp housing and the vehicle body. By adding a separate aiming mechanism for the upper beam, these gaps could be eliminated.

Valeo stated that these additional aiming mechanisms on the upper beam would not modify the accuracy of the aim of the lower beam function. Further, it would not modify the accuracy of the aim of the upper beam if lower and upper beam contributors can be illuminated separately. Separate illumination allows the “hot spot” of both the upper and lower beam contributors to be placed at the HV point.

Valeo stated that another merit of its petition is that of international harmonization. European regulations do not preclude separate upper and lower beam aiming mechanisms. If the petition was granted and FMVSS No. 108 amended, it would then be possible for manufacturers to produce only one category of headlamp for the whole world market resulting in substantial savings for manufacturers in both tooling costs and manufacturing organization.

Agency Analysis

As part of the justification for amendments allowing VOA headlamps in 1996, vehicle manufacturers indicated that they needed no horizontal aim adjustment because of the present accuracy of vehicle assembly and headlamp positioning on the assembly line. Because of this, and the fact that no reliable scientific Start Printed Page 68553method of achieving horizontal VOA has been determined, two major changes were made to FMVSS No. 108 relating to VOA headlamps: (1) The beam was made to be much wider and much less sensitive to horizontal misaim and, (2) no horizontal aiming screws or mechanisms other than a horizontal VHAD were permitted. Valeo needs separate aim adjustments to be incorporated for the upper beam contributors to maintain a uniform gap around the headlamp housing. As a consequence, it has petitioned to amend the standard to allow the upper beams to have their own horizontal and vertical aiming capabilities. In addition, to make the consumer aware of these additional aiming systems, Valeo recommended that the light emitting surface of each upper beam contributor be marked “VO.”

In 1996, a Regulatory Negotiation Committee that included representatives of foreign manufacturers worked with the agency over many months to achieve a consensus on all issues and the specific text of the amendment to FMVSS No. 108 to allow VOA headlamps. Because the present aiming requirements, as applied to VOA, were part of that consensus agreement, the agency is reluctant to change these requirements, absent a compelling safety reason to do so.

During the negotiated rulemaking, all of the vehicle manufacturers represented on the committee stated that they were capable of building vehicles as accurately as needed to install VOA headlamps. However, this degree of precision in assembly adds cost.

Valeo's petition is based on two rationales. The first is a desire to have an aesthetically pleasing headlamp by overcoming inaccuracies in the design and assembly of motor vehicles such that the headlamp housing may be purposefully misaimed, within a certain range, to help assure the desired visually symmetric size of the gap between the vehicle body and the headlamp or between the headlamp reflector and the surrounding headlamp housing. The second is to achieve harmonization with European standards.

Given Valeo's, as well as other manufacturers', desire for alternative aiming systems, the agency believes it is incumbent on Valeo and the industry to develop a single, objective method for vertical and horizontal aiming all VOA headlamps which could be incorporated into FMVSS No. 108. The agency does not intend to assess individual manufacturer's petitions for alternatives to the current requirements. The agency recently used a similar rationale to deny a petition from Federal-Mogul Lighting Products (Federal-Mogul) (66 FR 42985). Federal-Mogul petitioned to amend FMVSS No. 108 to allow headlamps that are aimed visually or optically to have a horizontal adjuster system that does not have the required ±2.5 degree horizontal adjustment range or the VHAD indicator required by the standard. In addition, the agency does not expect to give up the value that simultaneous beam aim provides. The agency believes that having simply aimed headlamps generally promotes more correctly aimed headlamps in the field. This is especially important, given the low incidence of periodic headlamp aim inspection in the United States and the likely lower level of experience of the service and inspection technicians and the public.

In accordance with 49 CFR part 552, the agency has reviewed the petition and concluded that it should not be granted. Accordingly, it denies Valeo's petition.

Start Signature

(49 U.S.C. 30118(d) and 30120(h); delegations of authority at 49 CFR 1.50 and 501.8)

Issued on October 31, 2002.

Stephen R. Kratzke,

Associate Administrator for Rulemaking.

End Signature End Supplemental Information

[FR Doc. 02-28558 Filed 11-8-02; 8:45 am]