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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 1791 - 1800 of 2914
Interpretations Date

ID: nht75-1.9

Open

DATE: 10/03/75

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Nissan Motor Co., Ltd.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your September 16, 1975, letter to Mr. John Carson of this agency, concerning Federal Motor Vehicle Safety Standard No. 101, Control Location, Identification and Illumination. You requested an interpretation of the footnote to Table 1 of the standard which reads: "Framed areas may be filled".

The National Highway Traffic Safety Administration interprets this footnote as permitting the vehicle manufacturer the option of depicting the interior of a symbol to which it applies with the same color as the boundary of the symbol, as an alternative to depicting the interior with the same color as the background. In the hazard warning signal symbol, which consists of a triangle containing a smaller triangle, only the area between the triangles is part of the interior. The center of the small triangle is part of the background. Therefore, only the first and third of the sampels submitted with your letter are permitted. For your convenience, I have enclosed a copy of the samples indicating which ones are permitted.

SINCERELY,

September 16, 1975

John W. Carson National Highway Traffic Safety Administration

I am writing this letter in regard to the hazard warning signal symbol mark in FMVSS 101 which reads:

"Framed area may be filled"

I would appreciate it very much if you could choose the best sample which I have drawn below. Please check if they are good or not good.

Thank you.

(Graphics omitted)

NISSAN MOTOR CO., LTD.

Naoyoshi Suzuki

Staff, Safety

(Graphics omitted)

ID: nht75-2.24

Open

DATE: 08/18/75

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: County of Los Angeles Road Department

TITLE: FMVSS INTERPRETATION

TEXT: Please forgive the delay in responding to your letter of April 28, 1975, concerning tires used on pull brooms.

Federal Motor Vehicle Safety Standard No. 119, New pneumatic tires for vehicles other than passenger cars, (copy enclosed), specifies labeling and performance requirements for all tires designed for use on pull brooms. This standard applies to all such tires manufactured on or after March 1, 1975. There is presently no requirement, however, that vehicles be equipped with tires conforming to the standard. The National Highway Traffic Safety Administration has proposed and is considering the issuance of a new Standard No. 120, Tire selection and rims for motor vehicles other than passenger cars, which would require all new pull brooms manufactured after its effective date to be equipped with tires conforming to Standard No. 119.

YOURS TRULY,

TO: Dear Sir

FROM: (Illegible Word)

Date 3-6-75

Please send me all the necessary information you have about implement (Illegible Words) (Illegible Line)

Thank you

76L265 Cdb 274 LOS ANGELES COUNTY LETTERGRAM

TO: E.T. Driver

FROM: Carl Morton

Subject: Implement tires.

Date: 4-28-75

Reply no N41-33

Our fleet of Pull Brooms are equipped with implement rib type tires. They are used 100% of the time on Highways.

Please advise

Thank you Carl Morton

ID: nht69-2.16

Open

DATE: 09/30/69

FROM: AUTHOR UNAVAILABLE; Robert Brenner; NHTSA

TO: Honorable John A. Blatnik

COPYEE: FHWA LEGAL 26-30; CONG. LIA.; MR. HITCKCOCK; OFF ACCIDENT AVOIDANCE, MVSPS

TITLE: FMVSS INTERPRETATION

TEXT: This is in further reply to your letter of September 9, 1969, in reference to the motor vehicle safety items discussed in Mr. Frank L. Van Alstine's letter of July 2, 1969, to Mr. H. M. Jacklin, Jr., Acting Director of our Motor Vehicle Safety Performance Service. I am enclosing a copy of our reply to Mr. Van Alstine's letter.

As we indicated in our reply, Federal Motor Vehicle Safety Standard No. 107, "Reflecting Surfaces - Passenger Cars, Multipurpose Passenger Vehicles, Trucks and Buses," affects only original installation; it does not apply to replacement windshield wiper arms, such as those referred to in Mr. Van Alstine's letter.

Federal Standard No. 210 specifies strength and general location requirements for lap and shoulder belt anchorages in passenger cars. Even though vehicles such as Mr. Van Alstine's 1969 Plymouth Valiant must meet this standard, some degree of discomfort may be experienced with certain(Illegible Word) positions and/or certain occupant sizes. As our reply stated, we are not aware of any significant injuries resulting from the present belt anchorage locations.

Based on the information supplied by Mr. Van Alstine, it does not appear that the two situations described represent violations of Federal Motor Vehicle Safety Standards.

It is most helpful to our efforts to improve highway safety when concerned citizens such as Mr. Van Alstine take the time to bring their safety experiences to our attention and that of their elected representatives.

Enclosure

ID: nht88-2.17

Open

TYPE: INTERPRETATION-NHTSA

DATE: MAY 5, 1988

FROM: I. ROBERT EHRLICH -- ENGINEER

TO: RICHARD STROMBOTNE -- NHTSA OFFICE OF SAFETY STANDARDS

ATTACHMT: ATTACHED TO MEMO DATED 12-19-88, TO I. ROBERT EHRLICH, FROM ERIKA Z. JONES -- NHTSA, REDBOOK A33, PART 571.3, PART 567

TEXT: Would you please send me a copy of NHTSA Docket 88-06, Notice 1 and Docket 88-07, Notice 1 proposing to strengthen the side impact crash test procedures and performance requirement for passenger cars, as indicated in the attached clipping from Automotive Engineering, APRIL 1988.

What I am particularly interested in is whether or not the proposed new standards will include stretch limousines, which are frequently covered by light sheet steel to fill in the gap created by lengthening a conventional passenger car. This leaves a wide, unprotected gap in the center.

Side Impact Protection -- The January 27, 1988, Federal Register contained NHTSA Docket 88-06, Notice 1 (page 2239), and Docket 88-07, Notice 1 (page 2254), proposing to strengthen the side impact crash test procedures and performance requirements for pa ssenger cars, and specifying a new side impact test dummy. The amendments would require a test procedure to simulate a severe side crash, a barrier to represent a striking vehicle, a test dummy specially designed for side impacts, and maximum injury crit eria for the dummy. Ten percent of a manufacturer's production would be required to meet the standard during the first year, which would begin two years after publication of the final rule. The percentage would increase to 25% the next year, 40% the thi rd year and 100% thereafter. Comments on both Notices are due October 24, 1988. For further information contact Dr. Richard Strombotne, NHTSA Office of Vehicle Safety Standards (202) 366-4916.

ID: aiam2083

Open
Mr. Lowell E. Schellhase, Motor Vehicle Inspection, 523 E. 12th Street, Des Moines, Iowa 50319; Mr. Lowell E. Schellhase
Motor Vehicle Inspection
523 E. 12th Street
Des Moines
Iowa 50319;

Dear Mr. Schellhase: This responds to your May 29, 1975, letter to Mr. Vincent Esposito o the National Highway Traffic Safety Administration (NHTSA), in which you indicate your desire that a 'second independent means of stopping be made mandatory' on newly-manufactured motor vehicles.; Federal motor vehicle safety Standard No. 105-75 (49 CFR 571.105-75 becomes effective January 1, 1976, for passenger cars, and it establishes requirements for the service and parking brake systems of these vehicles (copy enclosed).The test procedures for parking brake testing specify that the service brake control be released in testing the parking brake system. This has the practical effect of requiring a separate parking brake similar to that specified by the Iowa law you cited in your letter.; Federal motor vehicle safety Standard No. 121, (49 CFR 571.121) becam effective January 1, 1975, for air-braked trailers and March 1, 1975 for air-braked trucks and buses (copy enclosed). It establishes requirements for the service and parking brake systems of these vehicles. Section S5.6.4 of the standard states that 'The parking brake control shall be separated from the service brake control.'; Section 103(d) of the National Traffic and Motor Vehicle Safety Act i 1966 (15 U.S.C. 1392(d)) provides that no State or political subdivision of a State may promulgate or continue in effect standards applicable to on aspect of motor vehicle or motor vehicle safety standard, unless the standards are identical.; As noted, STandard No. 105-75 and Standard No. 121 include requirement for the parking brake control aspect of braking performance. The Federal requirements must be regarded as conclusive with regard to this aspect of performance in order to maintain the uniformity necessary in a Federal regulation scheme. If States were permitted to impose additional requirements in an area regulated by a Federal safety standard manufacturers would be confronted with an impossible task of compliance. This reasoning formed the basis of a recent decision rendered in a case brought by the Motorcycle Industry Council, Inc. against the State of California in the United States District Court for the Eastern District of California concerning the preemption of a California State requirement that motorcycle headlamps be wired to operate when the engine is running. The Court held that the California requirement is preempted by the Federal Motor Vehicle Safety Standard No. 108 since the NHTSA intended to cover all aspects of performance directly involving motorcycle headlamps.; Therefore, requirements such as those described in your letter would b preempted by Standard No. 105-75 in the case of passenger cars, since the aspect of performance that would be affected is covers by the Federal standard. The same is true for motorcycles, covered by Standard No. 122, *Motorcycle Brake Systems*, and trucks, buses, and trailers equipped with air brake systems, covered by Standard No. 121.; With regard to trucks, buses, and multipurpose passenger vehicles tha are equipped with hydraulic brake systems, the NHTSA is in the process of developing a hydraulic brake standard. I have forwarded a copy of your letter to the NHTSA Office of Crash Avoidance for consideration in developing the standard in this area.; Sincerely, Frank A. Berndt, Acting Chief Counsel

ID: aiam0827

Open
Mr. Roald Haugan, Director of Engineering, Airtex, 3558 Second Street North, Minneapolis, MN, 55412; Mr. Roald Haugan
Director of Engineering
Airtex
3558 Second Street North
Minneapolis
MN
55412;

Dear Mr. Haugan: This is in reply to your letter of June 28, 1972, concerning th application of Motor Vehicle Safety Standard No. 302, 'Flammability of Interior Materials'. You raise several questions in your letter which are restated below.>>>1. 'To which of the following does the law apply as of September 1, 1972:; a. New vehicles produced after that date. Standard No. 302 applies to all passenger cars, multipurpose vehicles trucks and buses manufactured on or after September 1, 1972.; b. 'New vehicles produced before that date, but *sold* to the publi after that date.'; Standard No. 302 applies only to vehicles manufactured on or afte September 1, 1972, and does not apply to vehicles manufactured before September 1, 1972, but sold to the public after that date.; c. 'Materials for interior repairs (replace headliner, etc.) made afte that date on vehicles produced *before* that date.'; d. 'Materials for interior repairs made after that date on vehicle produced after that date.'; e. 'Products designed for use in vehicles which are not origina equipment and usually not sold by auto dealers, but sold by after-market merchandisers - such items as infant seats, infant car beds, station wagon mattresses, elevating cushions, seat covers, pillows, speaker grills, curtains, gadget holders, litter bags, etc? If 'yes' to some or all of these, is it for those items *produced* by the original manufacturer or *shipped* to distributors or *sold* to the public after the Sept. 1 date?; Standard No. 302 does not apply to replacement parts or aftermarke materials irrespective of the date of their manufacture, shipment to distributors, or sale to the public.; 2. Standard No. 302 applies to passenger cars, multipurpose passenge vehicles, trucks, and buses manufactured on or after September 1, 1972. Among the vehicles you have listed, only the following are included under one of the classes to which the Standard is applicable: Jeeps, dune buggies (where constructed on a new chassis), motor coaches, motor homes, chassis mounted coaches, fire trucks, ambulances, and hearses.; 3. You ask whether testing the removable covering for seat cushions i motor coaches must include the zipper and the welting, and whether the fabric on 'non-visible surfaces' must be tested together with the fabric on the visible surfaces or not at all.; The zipper and the welting are considered part of the seat cover an would be included in the testing of the cover. The surface of the seat covering, irrespective of its visibility, must meet the requirements of the Standard. In your case, since the fabric on the visible surfaces differ from that on the non-visible surfaces, each of these fabrics must meet the requirements of the Standard.; 4. You ask whether the plastic foam used for cushioning in the mattres of a station wagon or multipurpose vehicle is subject to the Standard.; S4.2 of the Standard lists mattress covers only, and does not apply t the filling of the mattress.; 5. You ask whether the 'boot' on a pick-up camper is subject to th Standard.; We would not consider the boot as you describe it to be part of th truck, and it would not therefore be subject to the Standard.<<<; Yours truly, Richard B. Dyson, Assistant Chief Counsel

ID: nht74-1.19

Open

DATE: 09/23/74

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Dexter Axle Company, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your August 19, 1974, request to be advised of the steps necessary to acquire a manufacturer code number as required by Standards No. 119, New pneumatic tires for vehicles other than passenger cars, and No. 120, Tire selection and rims for motor vehicles other than passenger cars.

Standard No. 119 applies to tires-only and it is the responsibility of the tire manufacturer to obtain a code number and label it on his products. As a user of tires, you do not have obligations under this standard.

Standard No. 120 is a proposal which applies to rim construction and the selection of the correct rim for the (Illegible Word) equips. As a manufacturer of rims you would have a responsibility to label your products if this proposal becomes an effective regulation. However, we noted in the preamble to that proposal (copy enclosed) that we will not require manufacturer codes until a separate manufacturer code system has been established.

I am also enclosing a copy of the most recent proposal on manufacturer codes.

Yours truly,

ATTACH

August 19, 1974

Docket Section NHTSA

Re: FMVSS 119 and 120

Dear Sir:

Dexter Axle Co. Inc. is a manufacturer of running gear equipment for Mobile Homes and Recreational Vehicles. In our product line are wheels and rims subject to standards 119 and 120.

Please advise on the steps we must take to obtain a manufacturers code number as required.

Thank you.

Very truly yours, DEXTER AXLE COMPANY, INC.; J. A. Brown -- Manager - Engineering Res. & Dev.

ID: nht91-1.10

Open

DATE: January 3, 1991

FROM: Gene Schlanger -- President, ROC Capital, Inc.

TO: Taylor Vinson -- Legal Counsel, NHTSA

TITLE: None

ATTACHMT: Attached to letter dated 2-26-91 from Paul Jackson Rice to Gene Schlanger (A37; Std. 108)

TEXT:

We have developed a lighted sign (frame size 4 inches high x 23 inches wide) for Automobiles, with letters 2 inches high x 18 inches wide, that are illuminated by LEDs (light emitting diodes). Messages can be customized by the operator via a small, keyboard and stored in the key- board for instant recall by the driver or passenger. The sign can be designed to scroll messages from left to right along the face of the sign or if that is deemed legally inappropriate, the messages can remain stationary on the sign, with the changes in the message that just fade in and fade out. The sign is designed to be mounted inside the car, either on a rear or side window. If that is deemed legally inappropriate the sign can be designed to be placed outside on the roof of the auto, as would commonly seen lighted pizza signs on delivery cars, etc. ie: Domino's. The LEDS donot project beam, as would a headlight or directional light and donot flash, but instead allow the message to be read in day or night by passengers in other cars, or persons on the street, who are either to the rear or side, depending upon where the sign is mounted. We plan to program the sign, so that whenever it is turned on, it will automatically show an initial message saying: DRIVE SAFELY AND PLEASE DONOT TAILGATE. This sign would be sold to the general public.

We would appreciate receiving your opinion, as to whether a sign of this nature is within federal and/or state regulations, which may be applicable.

I look forward to hearing from you and to receiving any other information you feel may be helpful.

ID: nht88-3.81

Open

TYPE: INTERPRETATION-NHTSA

DATE: 11/01/88 EST

FROM: ERIKA Z. JONES -- CHIEF COUNSEL, NHTSA

TO: DAVE ANDERSON -- SALES MANAGER, GIST ORNAMENTAL IRON WORKS

ATTACHMT: NOT INCLUDED

TEXT: This responds to your letter about Federal requirements for trailers. According to your letter, you are in the planning stages of becoming a manufacturer of, and dealer for, automobile trailers. The trailers would hitch to the back of automobiles and b e designed to carry cargo. You noted that in response to an earlier inquiry, you received a copy of the handout entitled "Information For New Manufacturers of Motor Vehicles and Motor Vehicle Equipment." You stated that you are unclear just how this app lies to automobile trailers. You asked what you need to do to comply with any applicable Federal regulations, and what regulations apply to trailers of the kind you plan to build.

Trailers are considered motor vehicles under federal law. As a manufacturer of motor vehicles, you would be required to submit identification information to the National Highway Traffic Safety Administration (NHTSA) under 49 CFR Part 566, Manufacturer I dentification. You would also be required to certify that each trailer complies with all applicable Federal safety standards. The procedure is specified in 49 CFR Part 567.

The following safety standards apply to trailers: Safety Standard No. 108, Lamps, Reflective Devices, and Associated Equipment, Safety Standard No. 115, Vehicle Identification Number -- Basis Requirements, Safety Standard No. 119, New Pneumatic Tires for Vehicles Other Than Passenger Cars, Safety Standard No. 120, Tire Selection and Rims for Motor Vehicles Other Than Passenger Cars. The content requirements for the vehicle identification number are found at 49 CFR Part 565. In addition, trailers with certain braking systems must meet Safety Standard No. 106

Brake Hoses, Safety Standard No. 116, Motor Vehicle Brake Fluids, and Safety Standard No. 121, Air Brake Systems. All of these safety standards are found in 49 CFR Part 571.

I hope this information is helpful.

ENCLOSURE

ID: 3146o

Open

Mr. Dave Anderson
Sales Manager
Gist Ornamental Iron Works, Inc.
l2l27 Woodside Avenue
Lakeside, CA 92040

Dear Mr. Anderson:

This responds to your letter about Federal requirements for trailers. According to your letter, you are in the planning stages of becoming a manufacturer of, and dealer for, automobile trailers. The trailers would hitch to the back of automobiles and be designed to carry cargo. You noted that in response to an earlier inquiry, you received a copy of the handout entitled "Information For New Manufacturers of Motor Vehicles and Motor Vehicle Equipment." You stated that you are unclear just how this applies to automobile trailers. You asked what you need to do to comply with any applicable Federal regulations, and what regulations apply to trailers of the kind you plan to build.

Trailers are considered motor vehicles under Federal law. As a manufacturer of motor vehicles, you would be required to submit identification information to the National Highway Traffic Safety Administration (NHTSA) under 49 CFR Part 566, Manufacturer Identification. You would also be required to certify that each trailer complies with all applicable Federal safety standards. The procedure is specified in 49 CFR Part 567.

The following safety standards apply to trailers: Safety Standard No. l08, Lamps, Reflective Devices, and Associated Equipment, Safety Standard No. ll5, Vehicle Identification Number--Basic Requirements, Safety Standard No. ll9, New Pneumatic Tires for Vehicles Other Than Passenger Cars, Safety Standard No. l20, Tire Selection and Rims for Motor Vehicles Other Than Passenger Cars. The content requirements for the vehicle identification number are found at 49 CFR Part 565. In addition, trailers with certain braking systems must meet Safety Standard No. l06, Brake Hoses, Safety Standard No. ll6, Motor Vehicle Brake Fluids, and Safety Standard No. l2l, Air Brake Systems. All of these safety standards are found in 49 CFR Part 57l.

I hope this information is helpful.

Sincerely,

Erika Z. Jones Chief Counsel

ref: 571 d:ll/l/88

1970

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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