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NHTSA Interpretation File Search

Overview

NHTSA's Chief Counsel interprets the statutes that the agency administers and the standards and regulations that it issues. Members of the public may submit requests for interpretation, and the Chief Counsel will respond with a letter of interpretation. These interpretation letters look at the particular facts presented in the question and explain the agency’s opinion on how the law applies given those facts. These letters of interpretation are guidance documents. They do not have the force and effect of law and are not meant to bind the public in any way. They are intended only to provide information to the public regarding existing requirements under the law or agency policies. 

Understanding NHTSA’s Online Interpretation Files

NHTSA makes its letters of interpretation available to the public on this webpage. 

An interpretation letter represents the opinion of the Chief Counsel based on the facts of individual cases at the time the letter was written. While these letters may be helpful in determining how the agency might answer a question that another person has if that question is similar to a previously considered question, do not assume that a prior interpretation will necessarily apply to your situation.

  • Your facts may be sufficiently different from those presented in prior interpretations, such that the agency's answer to you might be different from the answer in the prior interpretation letter;
  • Your situation may be completely new to the agency and not addressed in an existing interpretation letter;
  • The agency's safety standards or regulations may have changed since the prior interpretation letter was written so that the agency's prior interpretation no longer applies; or
  • Some combination of the above, or other, factors.

Searching NHTSA’s Online Interpretation Files

Before beginning a search, it’s important to understand how this online search works. Below we provide some examples of searches you can run. In some cases, the search results may include words similar to what you searched because it utilizes a fuzzy search algorithm.

Single word search

 Example: car
 Result: Any document containing that word.

Multiple word search

 Example: car seat requirements
 Result: Any document containing any of these words.

Connector word search

 Example: car AND seat AND requirements
 Result: Any document containing all of these words.

 Note: Search operators such as AND or OR must be in all capital letters.

Phrase in double quotes

 Example: "headlamp function"
 Result: Any document with that phrase.

Conjunctive search

Example: functionally AND minima
Result: Any document with both of those words.

Wildcard

Example: headl*
Result: Any document with a word beginning with those letters (e.g., headlamp, headlight, headlamps).

Example: no*compl*
Result: Any document beginning with the letters “no” followed by the letters “compl” (e.g., noncompliance, non-complying).

Not

Example: headlamp NOT crash
Result: Any document containing the word “headlamp” and not the word “crash.”

Complex searches

You can combine search operators to write more targeted searches.

Note: The database does not currently support phrase searches with wildcards (e.g., “make* inoperative”). 

Example: Headl* AND (supplement* OR auxiliary OR impair*)
Result: Any document containing words that are variants of “headlamp” (headlamp, headlights, etc.) and also containing a variant of “supplement” (supplement, supplemental, etc.) or “impair” (impair, impairment, etc.) or the word “auxiliary.”

Search Tool

NHTSA's Interpretation Files Search



Displaying 13121 - 13130 of 16517
Interpretations Date

ID: nht92-4.17

Open

DATE: September 4, 1992

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Bill Traylor -- Waste Processing Equipment, Inc.

TITLE: None

ATTACHMT: Attached to letter dated 7/14/92 from Bill Traylor to Office of Chief Council, NHTSA (OCC-7544)

TEXT:

This responds to your letter of July 14, 1992, concerning certification of the trucks you are constructing on WCA Series Volvo GMC Class 8 truck chassis. As I understand it, you are planning to install your own coach body on the standard chassis purchased from Volvo.

I am pleased to have this opportunity to explain our regulations to you. Some background information on Federal motor vehicle safety laws and regulations may be helpful. As you are aware, the National Highway Traffic Safety Administration (NHTSA) is authorized under the National Traffic and Motor Vehicle Safety Act (15 U.S.C. S1381, et seq., "the Safety Act") to issue safety standards applicable to new motor vehicles and certain items of motor vehicle equipment. NHTSA, however, does not approve motor vehicles or motor vehicle equipment, nor do we "certify" individual manufacturers. Instead, the Safety Act establishes a "self-certification" process under which each manufacturer is responsible for certifying that its products meet all applicable safety standards. In addition, each manufacturer is required to notify NHTSA of the types of vehicles it is constructing.

Waste Processing Equipment, Inc. is considered a final-stage manufacturer under 49 CFR S568.3 because it "performs such manufacturing operations on an incomplete vehicle that it becomes a completed vehicle." In other words, when your company purchases a standard chassis from Volvo, i.e., an incomplete vehicle, it upgrades the chassis to a completed vehicle, i.e., one which requires no further manufacturing operations to perform its intended function (other than adding readily attachable parts such as mirrors or minor operations such as painting).

As a final-stage manufacturer, under 49 CFR S568.6, Waste Processing Equipment must complete each vehicle in such a manner that it conforms to all relevant federal standards, and then must affix a label to the vehicle according to the requirements of 49 CFR S567.5. Your precise certification responsibilities would be dependent on the information provided by the manufacturer of the incomplete vehicle. Under 49 CFR Part 568, the incomplete vehicle manufacturer must furnish your company with a document which states one of the following three things concerning the incomplete vehicle:

1. The vehicle when completed will conform to some or all of the applicable safety standards if no alterations are made to any identified components of the incomplete vehicle;

2. The vehicle when completed will conform to some or all of the applicable safety standards if specific conditions are followed by the final-stage manufacturer; or

3. Conformity with some or all of the applicable safety standards is not substantially affected by the design of the incomplete vehicle, so the incomplete vehicle manufacturer makes no representation as to conformity with the standards.

I have enclosed sections 567 and 568 for your convenience.

This means that, if your company completes these vehicles in accordance with the specifications Volvo GMC furnishes with the chassis, your certification of the completed vehicle may be based entirely upon Volvo GMC's specifications. However, if the Volvo GMC chassis does not include specifications for all safety standards or if your company chooses to complete the vehicle outside of the specifications provided by Volvo GMC, your company would be responsible for the certification of the completed vehicle. Accordingly, you should review the Volvo GMC specifications to see if you can complete the vehicle in accordance with those specifications.

As a general matter, final-stage manufacturers are also responsible for notification and remedy of defects related to motor vehicle safety and items not in compliance with applicable Federal motor vehicle safety standards, as specified in the Safety Act (15 U.S.C. S1411-1420), and are subject to the requirements of 49 CFR Part 573, Defect and Noncompliance Reports. In addition, each manufacturer is responsible for furnishing to NHTSA information regarding vehicles they manufacture under 49 CFR Part 566, a copy of which is enclosed.

I am also enclosing a general information sheet for manufacturers of new vehicles. This sheet highlights the relevant Federal statutes and regulations and explains how to obtain copies of the regulations.

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

ID: nht92-4.18

Open

DATE: September 4, 1992

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Kevin B. Brown -- EG&G Idaho, Inc.

TITLE: None

ATTACHMT: Attached to letter dated 5/6/92 from Kevin B. Brown to NHTSA (OCC-7323)

TEXT:

This responds to your letter concerning 49 CFR 567 requirements for intermediate or final stage manufacture vehicle labeling. I apologize for the delay in responding. You stated in your letter that EG&G Idaho, as prime contractor for the Department of Energy, Idaho Field Office, procures and maintains all government-owned vehicles, and occasionally procures truck chassis purchased through the General Services Administration for subsequent mounting of service bodies.

I am pleased to have this opportunity to explain our regulations to you. Before addressing the specific issues raised in the letter, some background information may be helpful. The National Traffic and Motor Vehicle Safety Act of 1966, as amended, 15 U.S.C., S1381-1431 (hereinafter "Safety Act") authorizes this agency to establish Federal motor vehicle safety standards for new motor vehicles and items of motor vehicle equipment. NHTSA, however, does not approve motor vehicles or motor vehicle equipment. Rather, the Safety Act establishes a self-certification process which requires each manufacturer, in the exercise of due care, to ensure and certify that its products meet all applicable Federal safety standards. Thereafter, NHTSA periodically tests vehicles and equipment for compliance with the standards and investigates allegations of safety-related defects.

In addition, the Safety Act only requires new vehicles to comply with applicable safety standards. The only provision of the Safety Act that would apply after the first purchase of a vehicle is 15 U.S.C. S1397(a)(2)(A), which states in relevant part that:

No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or in part, any device or element of design installed on or in a motor vehicle ... in compliance with an applicable Federal motor vehicle safety standard.

The first question to be answered is whether EG&G Idaho is a manufacturer. Under 49 CFR 568.3, a final-stage manufacturer is "a person who performs such manufacturing operations on an incomplete vehicle that it becomes a completed vehicle." An incomplete vehicle is "an assemblage consisting, as a minimum, of frame and chassis structure..." that requires "further manufacturing operations, other than the addition of readily attachable components... ." Readily attachable components include items such as mirrors or tire and rim assemblies. Service bodies are not "readily attachable components." Therefore, in installing service bodies on new chassis, EG&G is acting as a final-stage manufacturer under federal regulations.

49 CFR 586.6 establishes certain requirements for final-stage manufacturers,

including:

(a) Each final-stage manufacturer shall complete the vehicle in such a manner that it conforms to the standards in effect on the date of the manufacture of the incomplete vehicle, the date of final completion, or a date between those two dates. ... (b) Each final-stage manufacturer shall affix a label to the completed vehicle in accordance with S567.5 of this chapter.

EG&G must attach the proper label to the completed vehicle as set out in 49 CFR 567.5(c), a copy of which is enclosed for your convenience. According to your letter, EG&G mounts bodies in accordance with the original (i.e., incomplete) manufacturer's instructions or recommendations. In that case, EG&G's certification that the completed vehicle conforms to all applicable safety standards can state simply that the vehicle has been completed in accordance with the prior manufacturer's instructions, per S567.5(c)(7).

When EG&G mounts a new body on a new chassis, the resulting vehicle is subject to the Safety Act and the certification requirements of 49 CFR 567 and 568. However, according to your letter, you also mount bodies on "existing used" chassis. 49 CFR 571.7(e) deals with combining new and used components:

When a new cab is used in the assembly of a truck, the truck will be considered newly manufactured for purposes of paragraph (a) of this section (stating that safety standards apply to all relevant motor vehicles), the application of the requirements of this chapter, and the (Safety) Act, unless the engine, transmission, and drive axle(s) (as a minimum) of the assembled vehicle are not new, and at least two of these components were taken from the same vehicle.

This means that the vehicle resulting from placing a new body upon a used chassis is a used vehicle. If, in addition to adding a new body, the operation also modifies the chassis by adding new components, such as new engine, transmission, suspension, etc., it is more likely that the resulting vehicle would be considered a new vehicle. If your vehicles produced with "existing used chassis" will incorporate the engine, transmission, and drive axle from the existing used chassis, the completed vehicles would be "used" and would not require vehicle certification. Some of our standards, however, apply to individual items of motor vehicle equipment (e.g., brake hoses and fluids, lighting equipment, tires, seatbelt assemblies, glazing). If your converted vehicles incorporate new items of these types of equipment, the items must comply with the applicable Federal safety standards. For example, lights are subject to requirements specified in Standard No. 108, and glazing is subject to requirements specified in Standard No. 205.

Finally, you ask whether "EG&G Idaho need(s) to be certificated... ." There is no procedure to certify any manufacturer. It is the manufacturer that must certify that its vehicles meet the applicable federal safety standards. However, you should submit the manufacturer's information required by 49 CFR 566 to NHTSA. This information includes the name and address of the manufacturer (in this case, EG&G), a description of the type of vehicle manufactured, the use for which it is intended, and the fact that EG&G is a final stage manufacturer. I have enclosed a copy of Part 566 for your

information.

For your information, I have also enclosed a general information sheet for new manufacturers that gives a succinct outline of the relevant NHTSA regulations and explains how to get copies of those regulations.

I hope this information is helpful. If you have any further questions or need some additional information on this subject, feel free to contact David Elias of my staff at this address or by telephone at (202) 366-2992.

ID: nht92-4.19

Open

DATE: September 4, 1992

FROM: Dale E. Dawkins -- Director, Vehicle Compliance and Safety Affairs, Chrysler

TO: Paul Jackson Rice -- Chief Counsel, NHTSA

COPYEE: S. R. Kratzke -- NHTSA; S. Backaitis -- NHTSA; D. Cohen -- NHTSA

TITLE: None

ATTACHMT: Attached to letter dated 10/2/92 from Paul Jackson Rice to Dale E. Dawkins (A40; Std. 208)

TEXT:

Chrysler Corporation herein announces its intention of making a modification to the Hybrid III (49 CFR Part 572 Subpart E) test dummy for the purpose of enhancing the reliability of the chest deflection measurement system.

Several years ago Chrysler elected to use the Hybrid III test dummy for motor vehicle occupant protection development and compliance testing. Recently, we have discovered what we consider to be a technical shortcoming of the Hybrid III test dummy chest deflection measurement system that makes it unacceptable, without modification, for testing two-point motorized seat belt systems. Chest deflection measurements have been an ongoing issue between the industry and NHTSA for some time. In angular and frontal impacts, the torso belt deflects the chest in a combination of fore-aft and lateral directions. The lateral deflection component in conjunction with fore-aft deflection causes the rubber bump stops (PN 78051-356) on the inside surface of the sternum to interfere with the slider rod (PN 78051-353) of the chest deflection transducer. When this interference occurs during a vehicle barrier impact test, frequently the ball on the end of the chest deflection rod will pop out of the Delrin guide track it rides in causing the chest deflection measurement to be erroneous. This malfunction of the Hybrid III test dummy has caused us to question several tests of future vehicles necessitating retest.

We have made high speed fiber optic video recordings that confirm the sternum bump stops can interfere with the chest deflection rod, act as a fulcrum and pry the ball on the deflection rod out of its slider track. The rod and rotary potentiometer then indicate erroneous, erratic, nonsensical chest defections. Chrysler and others, through the SAE Dummy Testing Equipment Subcommittee, have learned that relocating one or both of the bump stops from the sternum to the spine of the Hybrid III dummy can alleviate this measurement problem and permit Hybrid III chest deflection measurements. We believe the relocation of the bump stops from the sternum to the spine box is useful and necessary and with due care will not affect the calibration or measurement accuracy of the chest deflection transducer or biofidelity of the Hybrid III thorax.

It is our understanding that the changes proposed are consistent with NHTSA policy. Chrysler hereby notifies the agency of its intentions to relocate the sternum bump stops to the spine (as shown) so that certification testing of a 1994 model year motor vehicle to MVSS 208 may proceed using the Hybrid III.

We understand that using the Hybrid II (49 CFR Part 572 Subpart B) test dummy is an option we have available to us. However, we are reluctant to use the Hybrid II because we prefer the Hybrid III for its superior biofidelity.

Your expeditious acknowledgement of this notice will be very appreciated.

ID: nht92-4.2

Open

DATE: 09/17/92

FROM: MARK W. RUSSO

TO: WALTER MYERS -- NHTSA

ATTACHMT: ATTACHED TO LETTER DATED 12-7-92 FROM PAUL J. RICE TO MARK W. RUSSO (A40; STD. 222); ALSO ATTACHED TO LETTER DATED 7-14-92 FROM PAUL RICE TO MICHAEL F. HECKER (STD. 222)

TEXT: Thank you for discussing the R-Bar subject with me. As I mentioned in our conversation, I am very concerned over the "applicability" issue regarding the R-Bar and FMVSS 222. I fear that a device not covered by a "Federal Motor Vehicle Safety Standard" may be installed in a school bus that will be transporting my children!

In addition to our conversation, I want to stress one area where I believe this device creates a condition that could be considered in non compliance with the objectives of FMVSS 222, section S5.1.4 (c). With reference to a NHTSA letter from Mr. Rice to Mr. Hecker (Micho, Ind.) dated May 14, 1992, which indicates that Mr. Hecker claims the device incorporates a design that allows it to "move upward, and away, from the adjoining seat which would thus allow the minimum clearance as intended". Being familiar with the operating principle of this device, I tend to agree in theory. However, what Mr. Hecker fails to mention is that the device also incorporates a "drop down" feature (by nature of a positive mechanical action) which is activated by forward movement of the device! Thus, if a passenger is "recoiled" forward, or if a subsequent frontal collision occurs, impact with the bar should activate this approximate 2 inch drop down feature. So, if there is any concern regarding minimum clearance in accordance with section S5.1.4 (c), it appears the operating principle of this device complicates the problem. Further, I also believe this "drop down" mechanism, in the above scenario, could create the potential for the bar to become jammed against a passenger's legs as a result of this "roller and track" drop down mechanism.

I would also like to know if there has been any further developments at NHTSA regarding the R-Bar subject since Mr. Rice responded to Mr. Hecker of Micho (May 14 letter from NHTSA). The N.J. Department of Pupil Transportation is under the impression that Micho Industries had planned to write to NHTSA again to suggest that only a different "interpretation" of their test data would resolve this issue.

I have a list of questions I am sending to Micho Industries covering many of the things you and I had discussed. I will keep you advised as to their response to these questions and any other new developments. I would appreciate any comments you may have regarding this R-Bar subject.

ID: nht92-4.20

Open

DATE: 09/02/92

FROM: JAMES A. WESTPHAL --OSHKOSH CHASSIS DIVISION, OSHKOSH TRUCK CORPORATION

TO: ADMINISTRATOR -- NHTSA

ATTACHMT: ATTACHED TO LETTER DATED 11-03-92 FROM PAUL J. RICE TO JAMES A. WESTPHAL (A40; STD. 121)

TEXT: The purpose of this letter is to seek clarification as to which Federal Motor Vehicle Safety Standards for brake systems must the vehicles described herein comply.

Oshkosh Chassis Division of Oshkosh Truck Corporation is a manufacturer of incomplete vehicles (chassis less cab). The chassis being addressed in this letter are sold to manufacturers who complete and sell the vehicles as "motor homes". The chassis for which we are requesting clarification are the "X" and "V" models both of which are over 10,000 pounds GVWR but no larger than 26,000 pounds GVWR.

We plan to install brake systems in these two models which use compressed air to provide braking power, and hydraulic fluid to transmit the energy to the hydraulically activated disk brakes at each wheel. This system is commonly known as "air-over-hydraulic" brakes. Please refer to the attached diagram showing the service brake system logic. The air components of the system include an air compressor and pressure governor, air dryer, air reservoirs, service brake control (treadle) valve, parking brake control valve and spring applied/air release parking brake chamber, and piping/valves/gauges/switches as required. Energy from the compressed air is transmitted to the hydraulic fluid through two air/hydraulic converters (brake boosters). The converter/booster increases the output hydraulic pressure approximately 16 times greater than the input air pressure. The hydraulic components of the system include disk brakes at each wheel, fluid reservoirs, and piping between the air hydraulic converters and disk brakes. Split service brake systems will be used.

Please answer the following compliance questions concerning the vehicles and brake system described above:

1. Must the brake system comply with the requirements of FMVSS 121 applicable to trucks?

2. Must the brake system comply with requirements of FMVSS 105 applicable to multipurpose passenger vehicles?

3. If SS121 compliance is required must the hydraulically powered disk brakes comply with Section S5.4 Service brake system-dynamometer tests?

4. If compliance to parts of both SS121 and SS105 is required must the system meet the requirements of SS105 Sections S5.1.2 Partial failure, S5.1.3 Inoperative brake power assist or brake power unit, and/or S5.3 Brake system indicator lamp?

Thank you for your consideration and response to these questions.ATTACHMENTS (TEXT AND GRAPHICS OMITTED.)

ID: nht92-4.21

Open

DATE: 09/01/92 EST

FROM: JULIA WALL -- HEAD, THE TRINITY SCHOOL OF TEXAS

TO: DOT

ATTACHMT: ATTACHED TO LETTER DATED 11-03-92 FROM PAUL J. RICE TO JULIA WALL (A40; PART 571.3)

TEXT: Please send a copy, of the federal law that regulates student transportation in general and as it specifically relates to multiple passenger vans.

Thank you for your assistance. The copy should be sent to:

ID: nht92-4.22

Open

DATE: 09/01/92 EST

FROM: PAUL GOULD -- SENIOR ENGINEER, FRICTION MATERIALS, LUCAS HEAVY DUTY BRAKING SYSTEM

TO: PAUL RICE -- NHTSA

ATTACHMT: ATTACHED TO LETTER DATED 11-19-92 FROM PAUL J. RICE TO PAUL GOULD (A40; STD. 121)

TEXT: I have recently been conducting dynamometer tests to FMVSS 121, here at Cwmbran, and I have some questions which I would like to pose to you as a matter of clarification on the actual meaning of "Average deceleration Rate" and its tolerance.

Taking the Brake Power Test, as an example, the FMVSS states: S5.4.2 "shall be capable of making 10 consecutive decelerations at an average of 9fpsps".

When conducting such tests on our dynamometers, we would carry these out in Constant Torque Mode. The dynamometer is given a deceleration to achieve, and the pressure is modulated around that figure depending on the frictional variations during the stop.

For the Brake Power Test, the dynamometer would attempt to achieve 2.7 m/s2 (in SI units) or 26.49%g.

A typical result obtained from out tests is: Stop 1 26.55%g Stop 2 26.17%g Stop 3 25.93%g Stop 4 26.10%g Stop 5 26.13%g Stop 6 26.05%g Stop 7 25.85%g Stop 8 25.96%g Stop 9 25.94%g Stop 10 25.63%g

This represents a control capability to within 5% (although on the low side).

The FMVSS does not however state this either as a minimum or maximum deceleration.

The points on which I require clarification are:

1) Results presented in this way appear to be lower than required for FMVSS, however, given that only a 5% shift exists are these acceptable, bearing in mind that the more crucial requirements are the pressure limitations and the Hot Stop deceleration rate.

2) It is my interpretation that the deceleration rate is only a Target in order to fade the Linings, and to within an error of 5%, our method is acceptable, rather than aim for a higher deceleration rate, which may mean much higher average deceleration than that stated in the FMVSS. This is also not strictly correct. I also wish to add that during the testing, the pressure utilised was well within the FMVSS demands.

I am sure that it is just a matter of interpretation, but it is vital to clear this up for future testing commitments.

ID: nht92-4.23

Open

DATE: August 28, 1992

FROM: Paul Jackson Rice -- Chief Counsel, NHTSA

TO: Steven Henderson -- Department of Psychology, McGill University

TITLE: None

ATTACHMT: Attached to letter dated 8/11/92 from Steven Henderson to Paul Jackson Rice (OCC-7640)

TEXT:

This responds to your letter of August 11, 1992, commenting on my response to you of June 29 with respect to the relationship of your motorcycle headlamp warning device to S5.6 of Federal Motor Vehicle Safety Standard No. 108, the provisions regulating the modulation of motorcycle headlighting systems.

In my letter, I informed you that the device would not comply with the requirements of Standard No. 108, and would affect compliance of the taillamps and turn signal lamps with the standard. I also advised you that if a motorcycle owner could install the device, there would be no violation of Federal law, and that the legality of its use would be determinable under the laws of the individual American states.

In your latest letter, you "agree that the device contravenes the letter of DOT Standard No. 108 as it presently stands." However, "if the device violates the letter of the law while satisfying the spirit or inferred intent of the law in each case," you believe "that the granting of an exception should be considered by the NHTSA."

As I understand it, your principal argument as raised on page 2 of your August 11 letter is that it is improper to consider your device under S5.6 as it is not a motorcycle headlamp modulating system as described in that section. Thus our objections to modulation rate and intensity, based upon the specifications of that section, are misplaced.

Assuming for the sake of argument that you are correct, your device becomes subject to another provision of Standard No. 108 that I did not mention in my June letter. Paragraph S5.1.3 prohibits the installation, as original equipment, of any motor vehicle equipment that impairs the effectiveness of lighting equipment that Standard No. 108 requires. Application of paragraph S5.1.3 returns us to my comments in June that your device would affect compliance of the taillamps and turn signal lamps with Standard No. 108. The taillamps would no longer be steady-burning, as required by S5.5.10(d). It would appear that the turn signal rate would also cease to comply with the flash rate of 60-120 per minute specified by SAE requirements incorporated by reference in Standard No. 108. Thus, under paragraph S5.1.3, installation of the device as aftermarket equipment, if performed by a manufacturer, dealer, distributor, or motor vehicle repair business would continue to be prohibited by Federal law.

Your latest letter also addresses the issues of taillamp and turn signal conformance. You argue that

"a taillight's purpose is to mark the rear of a motor vehicle during

nighttime driving when it would otherwise be invisible. For this reason the law requires that taillights be lit at night. The law makes no such requirement during the day. The law does require that motorcycle headlights be lit during the day. *** At night the taillight will always be steady- burning as required by S5.5.10(d) because the flasher device is only able to induce taillight flicker during daylight hours due to the photocell circuitry incorporated to prevent the headlamp from generating strobe effects at night. Therefore, the device is in compliance with S5.5.10(d) as it will cause the taillight to flash only at times that it is not required by law to be lit."

The law that applies to your argument is Standard No. 108. Paragraph S5.5.7(b) states in pertinent part that "On each...motorcycle...when the headlamps are activated in a steady-burning state, the taillamps...shall also be activated." Thus, under Standard No. 108 the taillamps must always be activated when the headlamps are activated.

The device also functions through the horn button to cause the turn signal lamps to flash at a rate higher than the maximum permitted by Standard No. 108. In your view, the situation in which the turn signal and horn button are in simultaneous use will be rare. However, if they are used together, "the SAE-specified turn signal flash of 1-2 hz will be perceptually present, the hazard signal flash of 10 hz will also be perceptually present at the same location, and the two signals will not interfere."

We consider that paragraph S5.1.3 applies here as well, and that a flash of 10 hz would impair the effectiveness of the required turn signal flash of 1-2 hz. There could be another undesirable consequence as well. When NHTSA proposed allowing modulating headlamps, commenters were concerned that the flashing might trigger a photic reaction, akin to an attack of epilepsy, in onlookers. NHTSA observed that the reaction was most likely to occur at a frequency of 10 hz against a very dark background. Although your device does not operate at night, its frequency is at the threshold where photic reactions can occur, and we want to bring this fact to your attention.

The agency shares your concern with improving the detectability of motorcycles and their riders. You have suggested writing an "exception" in Standard No. 108 for a period of one or two years so that the safety benefits of the device can be evaluated. We have a procedure under which a manufacturer of motorcycles can petition for a temporary exemption of up to two years, applicable to 2,500 vehicles per year, on the basis that it would facilitate the development and field evaluation of an innovative safety device. Perhaps you can interest a manufacturer in petitioning for a temporary exemption from Standard No. 108 on this basis.

You may also petition the agency for rulemaking to amend Standard No. 108 in a manner that would allow your device. A petition must set forth facts which it is claimed establish that a change in the standard is necessary, and a brief description of the changes which should be made. This means that you should show how your device is expected to improve safety, or, at a minimum, not decrease the existing level of safety. The agency has no plans to initiate rulemaking on its own initiative to permit your device.

ID: nht92-4.24

Open

DATE: August 25, 1992

FROM: Jerry Beck

TO: Mr. Rice

TITLE: None

ATTACHMT: Attached to letter dated 10/21/92 from Paul Jackson Rice to Jerry Beck (A40; VSA 102(4)

TEXT:

I have a product I would like to market at the consumer level. My product is reflective decals that would be placed on vehicles. I would like to know of any regulatory considerations before beginning to market the product.

To give you a better understanding about my product here is the basic idea. One decal will be placed on the back side of the rear view mirror and the other will be placed on the rear bumper. Sizes are approximately 2 x 8 inches for the front and 3 x 7 inches for the rear sign. Words and a symbol will only be reflective.

My concern is I do not want to market any product that would be either illegal or create a driving hazard. I have spoken with an accredited product testing company and they did not know what specification or if any apply to reflective decals. I would appreciate you providing me with any requirements so I can ensure my product will be both legal and safe for consumer use.

Since I have not started marketing yet please keep the information in this letter confidential. Thank you for your help in this matter.

ID: nht92-4.25

Open

DATE: August 25, 1992

FROM: Paul D. Barron -- Professional Technologies International Inc.

TO: Paul Jackson Rice -- NHTSA Chief Counsel; Marvin Shaw

TITLE: None

ATTACHMT: Attached to letter dated 10/22/92 from Paul Jackson Rice to Paul D. Barron (A40; Std. 205)

TEXT:

Thanks for your help on the possible requirements from NHTSA on our UV Heat Shield product. As I understand it this product can be self certified and needs no certification from the federal government.

Please confirm this in formal documentation to me at your earliest convenience.

Attachment

PRODUCT ANALYSIS SOLAR SHIELD

(Text and graphics omitted.)

Request an Interpretation

You may email your request to Interpretations.NHTSA@dot.gov or send your request in hard copy to:

The Chief Counsel
National Highway Traffic Safety Administration, W41-326
U.S. Department of Transportation
1200 New Jersey Avenue SE
Washington, DC 20590

If you want to talk to someone at NHTSA about what a request for interpretation should include, call the Office of the Chief Counsel at 202-366-2992.

Please note that NHTSA’s response will be made available in this online database, and that the incoming interpretation request may also be made publicly available.

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