ID: 1121-2

Mr. T.J. Sommer
President
White Bear Sales, Inc.
P.O. Box 16718
Milwaukee, WI 53216

Dear Mr. Sommer:

This is in reply to your FAX of July 28, 1995, to Taylor Vinson of this Office.

You report that Chicago's police department is using four- wheeled all terrain vehicles (ATVs) for patrol work in the downtown area, and that they have been licensed by Illinois for on-road use. You believe that the vehicles are illegal to use on the streets and that city employees are at risk. You have been asked by the director of Chicago's fleet "to compile all federal definitions and statutes which apply to the quad runners, regarding classification, certification, and compliance for street use." You have asked for our assistance.

I note first that while Federal law regulates the manufacture and sale of new motor vehicles, the individual States establish their own requirements for the licensing of motor vehicles. Therefore, the question of whether the ATVs may legally be used on the road is a matter of Illinois law rather than Federal law.

Your letter does, however, raise the issue of whether the manufacture and/or sale of the ATVs was consistent with Federal law. We do not have specific information about the ATVs at issue; however, I can provide general information about how Federal law applies in this area.

By way of background information, Chapter 301 of Title 49 of the U.S. Code authorizes NHTSA to issue safety standards for new motor vehicles and new motor vehicle equipment. All motor vehicles and items of motor vehicle equipment manufactured for sale in the United States must comply with all applicable safety standards set forth in 49 CFR Part 571.

The issue of whether the ATVs were required to comply with the Federal motor vehicle safety standards is dependent on whether they are considered "motor vehicles." I have enclosed several interpretation letters which address the criteria which NHTSA applies in determining whether a vehicle with on and off-road capability is a motor vehicle (addressed to Mr. Matthew Plache, dated December 3, 1991; Mr. Hiroshi Kato, dated October 31, 1988; Mr. Wayne Kirby, dated February 8, 1983; and Mr. Leonard Fink, dated March 25, 1982). If an ATV is a motor vehicle, it must be certified to comply with all applicable safety standards.

If, after reviewing this information, you believe that a violation of Federal law may have occurred, you may wish to contact Mr. Luke Loy of NHTSA's Office of Vehicle Safety Compliance at (202) 366-5288. If you have further questions about the applicability of our standards, please feel free to contact Mr. Taylor Vinson of my staff (202-366-5263).

Sincerely,

John Womack Acting Chief Counsel

Enclosures ref:VSA d:9/19/95

ID: nht76-3.40

DATE: 01/20/76

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Department of the Army

TITLE: FMVSR INTERPRETATION

TEXT: This responds to your December 11, 1975, request for copies of the Federal laws relevant to the use of trucks as carriers for snowplows and spreader bodies.

The National Highway Traffic Safety Administration (NHTSA) primarily regulates the manufacture of motor vehicles and motor vehicle equipment pursuant to authority of the National Traffic and Motor Vehicle Safety Act of 1966. You requested copies of the Federal laws pertinent to the "use" of a particular motor vehicle, but standards or laws regulating use are promulgated by the jurisdiction in which a motor vehicle is registered or driven.

It might be noted, however, that motor vehicle safety standards are applicable to the installation of snowplows and spreader bodies on new trucks. For example, paragraph S4.3.1.1 of Motor Vehicle Safety Standard No. 108, Lamps, reflective devices, and associated equipment (49 CFR 571.108), specifies that if motor vehicle equipment, including snowplows, would otherwise prevent compliance with the Standard by any required lamp or reflective device, an auxiliary lamp or reflective device meeting the requirements of the Standard must be provided. Similarily, when a spreader body is installed on a chassicab, the completed trucks must comply with all applicable Federal standards.

The truck dealer or other person who installs motor vehicle equipment on a truck that is certified as being in compliance with motor vehicle safety standards, prior to first sale of the vehicle, is responsible for ensuring that the truck remains in conformity. Failure to do so would constitute a violation of section 108(a)(1) of the National Traffic and Motor Vehicle Safety Act, and subject the responsible party to the civil penalty provisions and other sanctions of the Act.

When a truck has been sold and is in "use", the Act prohibits a manufacturer, distributor, dealer, or repair business from making alterations that render inoperative any devices or elements of design installed in compliance with the Federal safety standards.

Please contact us if we can be of any further assistance.

YOURS TRULY,

DEPARTMENT OF THE ARMY U.S. ARMY COLD REGIONS RESEARCH AND ENGINEERING LABORATORY

DECEMBER 11, 1975

National Highway Traffic Safety Administration Department of Transportation

In a study of snow removal equipment technology we are making for an NSF RANN project we have need for the federal laws applying to use of trucks as carriers for snowplows and spreader bodies (as well as dump bodies). Please furnish us with copies of the relevant laws, or a list which can be used to obtain them from other sources.

Thank you.

L. DAVID MINSK Research Physical Scientist Applied Research Branch

ID: nht75-3.42

DATE: 10/10/75

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Kelsey-Hayes Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Kelsey-Hayes Company's July 28, 1975, question asking whether the requirements of S5.1.6 of Standard No. 121, Air Brake Systems, that specify a warning signal "in the event of a total electrical failure of the antilock system" would permit installation on a vehicle of an antilock-equipped axle that has no capability to signal electrical failure of its antilock system. You state that the vehicle would be equipped with antilock systems on other axles that would provide a warning signal in the event of their electrical failure.

The answer to your question is yes. As you noted in your letter, the National Highway Traffic Safety Administration has interpreted the specifications of S5.1.6 to require a signal only in cases where electrical failure within the antilock electrical system circuitry causes loss of antilock control of every wheel on the vehicle. In the design you describe, the signal which activates upon loss of antilock control at one or more wheels on the vehicle would fulfill this requirement, because it would always activate by the time antilock control had been lost at every wheel on the vehicle. Under our interpretation of S5.1.6, a failure of antilock only on the axle described by you would not constitute "loss of antilock control of every wheel on the vehicle" and would not be required to be signaled.

SINCERELY,

KELSEY-HAYES COMPANY

July 28, 1975

National Highway Traffic Safety Administration

ATTN: James Schultz Chief Counsel

RE: Request for Interpretation FMVSS-121: Air Brake Systems 5.1.6, Antilock Warning Signal

Kelsey-Hayes Company, a domestic manufacturer of motor vehicle equipment including antilock systems, requests an interpretation of the above referenced section of Standard 121 as it relates to tag axles, liftable axles and removable dollies.

Interpretations on this section of the standard issued by your staff in the past, specifically one to Wagner Electric on May 26, 1972 and another to the Eaton Corporation dated December 26, 1974 state that the phrase "total electrical failure" means any electrical failure within the antilock electrical system circuitry which would cause loss of antilock control of every wheel on the vehicle.

Since an antilock system failure on one axle need not actuate the warning signal, we ask whether it is consistent with these interpretations to equip an axle on a vehicle, specifically a tag axle, liftable axle, or removable dolly, with an antilock system that does not have the capability to activate the warning signal in the event of an electrical failure. Electrical failures which would disable the antilock system on the wheels of the other axles would activate the warning signal such that the "total electrical failure" situation would be complied with. In other words, the total electrical failure situation cannot occur unless the antilock systems on the other axles are disabled and, if they are, the warning signal will be activated.

We have been advised by installers of tag axles that it is burdensome to match the antilock system of the tag axle with the same make as those originally equipped on the other axles of the vehicle and that making the necessary electrical connections to the failure detection circuits on the other axles creates unacceptable liability risks. The most practical means to mitigate this condition would be to use trailer type antilock system components, which do not have electrical failure detection capability, for tag axles and other axles customarily added by body builders, etc.

Your prompt attention to this request for interpretation will be appreciated.

John F. McCuer

ID: nht78-4.30

DATE: 06/09/78

FROM: LAWRENCE W. HENNEBGERGER; ROBERT L. GREEN -- ARENT FOX

TO: JOSEPH J. LEVIN -- CHIEF COUNSEL NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION

COPYEE: Z. TAYLOR VINSON, GERALD M. BLOOM; JOSEPH WALSH, ROBERT BRENNER

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 08/31/78 FROM JOSEPH J. LEVIN -- NHTSA TO LAWRENCE F. HENNEBERGER AND ROBERT W. GREEN; REDBOOK A26(3); STANDARD 108

TEXT: Dear Mr. Levin:

Our client, Jacobs Manufacturing Company, has manufactured and distributed its well-known diesel engine retarder (the "Jake brake") for a number of years. The Jake R brake is sold both in the OEM market as original engine equipment (by such companies as Cummins Engine Co. and Mack Truck, among others) and as an aftermarket installation. This retarder provides auxiliary retarding capabilities independent of the vehicle's foundation brakes and perm[Illegible Words] a heavy truck to travel at normal traffic speeds on long downgrades, under full control, as well as extending the service life of the foundation brakes.

In recent years, the retarding force generated by current-design engine retarders has increased considerably, and electric driveline retarders with markedly greater retarding horsepower have become available. For example, Jacobs is now marketing an electric retarder (the "Jake ERR"), rated at some two to three times the retarding force of a typical large diesel engine equipped with the Jake R brake.

Because retarding forces of this magnitude are capable of producing significant deceleration of a large truck so equipped, Jacobs believe that some means should be provided to warn following vehicles when a retarder is in use. In addition, since a truck tractor equipped with a retarder may be used to pull a variety of different semi-trailers, the warning system must utilize existing vehicle equipment and operate both on the tractor alone ("bob-tail" configuration) and with any semi-trailer that may be hooked up.

After careful analysis and based upon a meeting with NHTSA and BMCS representatives on June 6, 1978, Jacobs has concluded that use of the existing hazard warning flasher system would best provide such warning to following drivers. Many states now require trucks moving less than 40 m.p.h. on limited access highways to use their hazard warning flashers to alert other motorists that they are slow-moving.

In order to provide this retarder warning signal automatically, Jacobs proposes to connect the retarder activation switch to the hazard warning system when a retarder is installed, either at the OEM or aftermarket level. Accordingly, the Company requests an advisory opinion that such use and connection of the hazard warning system is permissive and will not violate the requirements of FMVSS 108, nor will it violate the "antitampering" provisions set out in section 108 (a) (2) (A) of the National Traffic and Motor Vehicle Safety Act of 1966, as amended.

Sincerely,

ID: 24183

Mr. James F. Flint
Grove, Jaskiewicz & Cobert
Suite 400
1730 M Street, NW
Washington, DC 20036-4517





Dear Mr. Flint:

This responds to your letter of March 8, 2002, in which you ask whether the tire pressure monitoring system (TPMS) manufactured by your client, Col-Ven SA of Argentina, for large commercial motor vehicles will be subject to the pending rulemaking on TPMSs. As discussed below, the agency did not propose to require TPMSs on medium and heavy vehicles in its proposed rule. However, we cannot give you a definitive answer at this time as to what the final rule will require.

In your letter, you state that Col-Ven SA manufacturers a TPMS intended for commercial motor vehicles with a gross vehicle weight rating over 26,000 pounds, including large trucks, truck tractors, tractor/trailer combinations, passenger buses, and large recreational vehicles.

In your letter you also refer to an April 29, 1998, National Highway Traffic Safety Administration (NHTSA) interpretation letter (see enclosure) regarding another TPMS manufactured for heavy vehicles. In that letter, NHTSA stated that there was no Federal Motor Vehicle Safety Standard (FMVSS) applicable to TPMSs. However, the agency cautioned that the installation of any such system, either as original equipment or as after-market equipment, is prohibited if it makes "inoperative any device or element of design that was originally installed on or in the vehicle pursuant to any FMVSS." The agency indicated that such a system might impact air brake systems (covered by FMVSS No. 121) or brake hoses (FMVSS No. 106).

You ask whether this interpretation letter has been superseded or altered by the passage of the Transportation Recall Enhancement, Accountability and Documentation (TREAD) Act, ⁽¹⁾ and whether TPMSs manufactured for large commercial motor vehicles will be subject to the rulemaking on TPMSs required by Section 13 of the TREAD Act.

Section 13 of the TREAD Act mandates the completion of "a rulemaking for a regulation to require a warning system in new motor vehicles to indicate to the operator when a tire is significantly under inflated." On July 26, 2001, NHTSA issued a notice of proposed rulemaking (NPRM) proposing a new FMVSS (No. 138) with requirements for TPMSs. ⁽²⁾ The agency proposed to require TPMSs on light vehicles, i.e., passenger cars, multipurpose passenger vehicles, trucks, and buses with a GVWR of 10,000 pounds or less. The agency did not propose to require TPMSs on medium (10,001 - 26,000 pounds GVWR) and heavy (greater than 26,001 pounds GVWR) vehicles.

NHTSA also noted in the NPRM that the Federal Motor Carrier Safety Administration (FMCSA) is addressing tire maintenance issues for heavy vehicles. FMCSA plans to conduct a comprehensive study, including possible fleet evaluations of different TPMSs, of all the issues related to improvement of heavy vehicle tire maintenance. The agency plans on working with FMCSA in examining the desirability of proposing a TPMS standard for heavy vehicles.

The agency received one comment requesting that we initiate a separate rulemaking to consider TPMS requirements for medium and heavy vehicles. We will address that comment in the final rule. In the meantime, we can tell you that the April 28, 1998 interpretation letter discussed above is valid with respect to medium and heavy vehicles.

I hope you find this information helpful. If you have any further questions on TPMSs, please feel free to contact Dion Casey of my staff at (202) 366-2992.

Sincerely,

Jacqueline Glassman
Chief Counsel

Enclosure
ref:138
d.4/22/02

---

¹ P.L. 106-414, November 1, 2000.

² 66 FR 38982.

ID: nht73-4.12

DATE: 04/19/73

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Milwaukee Truck Center Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of March 6, 1973, in which you ask several questions regarding the certification of trucks with concrete mixers. You state that you supply a chassis to the Rex Chainbelt factory in Milwaukee, where a concrete mixer is installed. The combined unit is then shipped to a Rex dealer in Puerto Rico who sells the complete unit to a user. You provide weight ratings for the vehicle as follows: a gross vehicle weight rating, based on axle capacity, of 68,000 pounds: a rating, based on the tire capacity, of 56,740 pounds, and a gross weight of 66,800 pounds. Based on these figures you ask (1) Whether the truck can be completed in this fashion and shipped by you to Puerto Rico; (2) Whether the dealer in Puerto Rico can promise to install larger tires at a later date; (3) Whether Rex Chainbelt can certify the chassis at 68,000 pounds gross weight rating if the dealer in Puerto Rico notifies Rex that he will change the tires at a later date (4) Whether the chassis manufacturer can certify the truck chassis for a greater capacity than the lightest component if the local dealer or customer will notify him that they will bring the chassis to the higher certified level, and (5) What penalties can be imposed if a dealer or user does not make changes he has promised to make.

It appears to us from your letter that essentially the same issue underlies all your questions; that is, whether a final-stage manufacturer in completing a vehicle may place on it tires that are not sufficient to carry the vehicle at its gross vehicle weight rating, and elicit a promise from either a dealer or user that the latter will change the tires.

A truck that is equipped at the tire of its manufacturer with tires inadequate in terms of load rating to carry the truck at its gross vehicle weight rating would be considered by NHTSA to contain a safety related defect. The manufacturer of such a vehicle is subject to the provisions of section 113 of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1402), which requires that notification of the defect be sent to first purchasers and dealers. A truck which was labeled with a gross vehicle weight rating below the minimum specified in 49 CFR 567(g)(3) would be in violation of the Certification regulations, and the person affixing such a label would be subject to civil penalties and other sanctions pursuant to section 108, 109, and 110 of the Safety Act (15 U.S.C. 1397, 1398, 1399). The Certification regulations (49 CFR Parts 567, 568) require weight ratings, in cases of vehicles manufactured in two or more stages, to be based on the vehicle as completed by the final-stage manufacturer. That manufacturer is not permitted to delegate his responsibility to a dealer or user.

The NHTSA has made an exception in the case of vehicles shipped without tires, or vehicles shipped with temporary tires that are not intended to be used on the vehicle apart from the limited purpose of shipment. Your letter contains no implication that your case is within this exception.

ID: Costa.1

Mr. Larry J. Costa
Costa Technologies
54201 Ash Road
Osceola, IN 46561

Dear Mr. Costa:

This responds to your letters of May 6, 2003, and May 7, 2003, in which you request interpretation of Federal Motor Vehicle Safety Standard (FMVSS) No. 205, Glazing Materials (49 CFR 571.205). Specifically, you asked whether the weight of a conductor is included along with attached glass fragments under Test No. 7 ("fracture test") when determining compliance with the requirement that no individual glass fragment may weigh more than 4.25 g (0.15 oz.), and if so, whether attachment of such conductors would result in a violation of 49 U.S.C. 30122. In a subsequent phone conversation with Eric Stas of this office, you stated that a subsequent soldering process or application of conductive adhesive may result in changes in the structure of the glass, such that when the glass breaks, certain glass fragments (either attached to a conductor or free-standing) may exceed 4.25 g.

FMVSS No. 205 specifies performance requirements for various types of glazing (called "items"). FMVSS No. 205 incorporates by reference American National Standard Safety Code for Safety Glazing Materials for Glazing Motor Vehicles Operating on Land Highways Standard ANSI Z26.1-1977, as supplemented by Z26.1a-1980 (hereinafter collectively referred to as "ANSI Z26-1980").

ANSI Z26.1-1980, Section 5.7, "Fracture, Test No. 7," limits the size of individual glass fragments that form as a result of impact to a glazing surface and requires that no individual fragment weigh more than 4.25 g (0.15 oz.). That test is conducted using twelve 12 x 12-inch (305 x 305 mm) flat specimens, without any attached conductors or other enhancements.

At present, FMVSS No. 205 does not specify requirements applicable to glazing to which conductors have been attached. However, as noted in our previous letter to you on this subject, NHTSA has been in the process of updating FMVSS No. 205 to incorporate a more recent version of ANSI-Z26, under which the glazing would need to be tested with conductors attached, if that condition represents the most difficult part or pattern designation within a given model number. On July 25, 2003, we published a final rule adopting the updated ANSI standard (68 FR 43964). Accordingly, this requirement will apply to all glazing certified on or after September 23, 2003, the effective date of the rule.

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

Sincerely,

Jacqueline Glassman
Chief Counsel

ref:205
d.7/25/03

ID: Costa_1

Mr. Larry J. Costa
Costa Technologies
54201 Ash Road
Osceola, IN 46561

Dear Mr. Costa:

This responds to your letters of May 6, 2003, and May 7, 2003, in which you request interpretation of Federal Motor Vehicle Safety Standard (FMVSS) No. 205, Glazing Materials (49 CFR 571.205). Specifically, you asked whether the weight of a conductor is included along with attached glass fragments under Test No. 7 ("fracture test") when determining compliance with the requirement that no individual glass fragment may weigh more than 4.25 g (0.15 oz.), and if so, whether attachment of such conductors would result in a violation of 49 U.S.C. 30122. In a subsequent phone conversation with Eric Stas of this office, you stated that a subsequent soldering process or application of conductive adhesive may result in changes in the structure of the glass, such that when the glass breaks, certain glass fragments (either attached to a conductor or free-standing) may exceed 4.25 g.

FMVSS No. 205 specifies performance requirements for various types of glazing (called "items"). FMVSS No. 205 incorporates by reference American National Standard Safety Code for Safety Glazing Materials for Glazing Motor Vehicles Operating on Land Highways Standard ANSI Z26.1-1977, as supplemented by Z26.1a-1980 (hereinafter collectively referred to as "ANSI Z26-1980").

ANSI Z26.1-1980, Section 5.7, "Fracture, Test No. 7," limits the size of individual glass fragments that form as a result of impact to a glazing surface and requires that no individual fragment weigh more than 4.25 g (0.15 oz.). That test is conducted using twelve 12 x 12-inch (305 x 305 mm) flat specimens, without any attached conductors or other enhancements.

At present, FMVSS No. 205 does not specify requirements applicable to glazing to which conductors have been attached. However, as noted in our previous letter to you on this subject, NHTSA has been in the process of updating FMVSS No. 205 to incorporate a more recent version of ANSI-Z26, under which the glazing would need to be tested with conductors attached, if that condition represents the most difficult part or pattern designation within a given model number. On July 25, 2003, we published a final rule adopting the updated ANSI standard (68 FR 43964). Accordingly, this requirement will apply to all glazing certified on or after September 23, 2003, the effective date of the rule.

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

Sincerely,

Jacqueline Glassman
Chief Counsel

ref:205
d.7/25/03

ID: nht72-5.32

DATE: 06/06/72

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Garsite Products Inc.

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of May 4, 1972, regarding the application of the Certification regulations (49 CFR Part 567) to tank truck manufacturers. Your questions are restated below, followed in each case by our response.

1. If a vehicle ends up with a gross weight over the GVWR of the chasis are we (or anyone in our industry) liable to prosecution?

If the loaded weight of the vehicle, or the weight on an axle system, exceeds the stated ratings, the vehicle may be found to contain a safety-related defect. While a vehicle manufacturer will not be liable to "prosecution", as that term is generally understood, the failure of a vehicle to conform to applicable standards may result in the imposition of a civil penalty against its manufacturer of up to $ 1,000 for each violation, and up to $ 400,000 for each series of related violations (15 U.S.C. 1398). If a defect that relates to motor vehicle safety is discovered in the vehicle, the manufacturer will be required to notify first purchasers (15 U.S.C. 1402).

2. Is it permissible to "derate" the volumetric capacity of a tank (by setting the liquid markers low) in order to stay within the GVWR?

In assessing the safety aspects of a vehicle, the NHTSA considers all factors in the situation. These factors would include both the manufacturer's rating and the true capacity of the vehicle. I should emphasize that it is the actual situation, rather than any artificial statements or rating, that we are primarily concerned with.

3. If we so "derate" a tank and the customer subsequently fills the tank, who would be responsible for the overweight?

The NHTSA does not regulate the user of a vehicle, although other State and Federal agencies do. The way in which a user loads his vehicle may, however, bring out a safety problem related to its load-carrying capacity. An important factor to be considered is the manufacturer's expectation as to how the vehicle is to be used at the time he sells it.

4. Due to the manufacturing variations in chassis weights, tank dimensions, etc., are we allowed any tolerance on the actual weight versus the GVWR or GAWR?

While your question is somewhat unclear, the answer generally is negative. Any "manufacturing variations" in components upon which these values are based must be taken into account by the manufacturer who assembles and labels the vehicle.

Finally, with reference to your complaint that certain of your competitors are not complying with the regulations, if you will furnish to us the names of the companies involved, we will be able to take whatever action is necessary to bring such companies into conformity with our requirements. We do not publish any booklets concerning the regulations, although various trade associations have undertaken to summarize them for their members.

ID: nht92-7.12

DATE: May 6, 1992

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Shigeyoshi Aihara -- Manager, Information Services, Ichikoh America, Inc.

TITLE: None

ATTACHMT: Attached to letter dated 3/16/92 from Shigeyoshi Aihara to Paul J. Rice (OCC 7113)

TEXT:

This responds to your letter of March 16, 1992, requesting an interpretation of the applicability of the fogging prohibition of S7.4(i)(6) of Federal Motor Vehicle Safety Standard No. 108.

Initially, we would like to call your attention to the fact that S7.4 (i)(6), which you quoted in its entirety, was amended on March 11, 1991, to delete the requirement that a headlamp meet the photometric requirements after a humidity test. S7.4 (i)(6) now states in pertinent part that, after a humidity test conducted in accordance with S8.7, "the inside of the headlamp shall show no evidence of delamination or moisture, fogging or condensation visible without magnification."

You have attached a drawing of a vented headlamp with an onboard aiming system. The headlamp is available with two different types of bubble indicators. Your first question is: "After the humidity test, both types ... show the fogging in the location as shown in attached sketches. But, this fogging is gone at normal temperature. *** Is such fogging acceptable after the temperature test?" Your second question is whether "'the inside of the housing' means the lens and reflector portions" or "the entire inside portion of headlamps?"

The humidity test was adopted in 1983. Allowing humidity or water in headlamps causes slow degradation of the reflector over the long term. The presence of humidity results in spots on the reflector and lens, and eventual photometric failure. The humidity test is designed to assure that the vents in vented headlamps eliminate moisture in the headlamp when exposed to air flow with the headlamps off, thus assuring adequate performance in long term use. The provision for onboard headlamp aiming devices was not adopted until 1989, and did not specify that they be located within the headlamp.

From the foregoing, it is evident that the humidity test for replaceable bulb headlamps was not adopted to address a problem inherent in the exposure of onboard aiming devices to moisture. These devices were not in use at the time the humidity test was added to Standard No. 108, and they do not contribute directly to the photometric performance of the headlamp.

From the diagram you enclosed, the aiming device appears located behind the reflector. It is not possible to determine from your letter whether moisture forms on the exterior or the interior of the aiming device. Although S7.4 (i)(6) prohibits moisture "inside the headlamp" and the aiming device is located inside the headlamp, we would not read the prohibition as extending to the aiming device if the moisture occurs inside that device.

Even if the moisture occurs on the exterior of the aiming device, it does not affect the photometric properties of the headlamp. The agency does not wish to impose inadvertent design restrictions that are not directed towards safety, and therefore regards any moisture that may occur on the exterior of the aiming device as outside the prohibition of S7.4 (i)(6). This interpretation, however, is limited to the specific design that you have presented.