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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 3271 - 3280 of 16490
Interpretations Date

ID: nht71-3.16

Open

DATE: 06/08/71

FROM: L. R. SCHNEIDER -- ACTING CHIEF COUNSEL, NHTSA; SIGNATURE BY DAVID SCHMELTZER

TO: Blue Bird Body Company

TITLE: FMVSR INTERPRETATION

TEXT: This letter is to further clarify an interpretation contained in our letter of Nov. 6, 1971, concerning the Tire Identification and Record Keeping Regulation.

We wish to make it clear that although the final-stage manufacturer may designate someone to maintain the records required under section 574.10 of the Tire Identification and Record Keeping Regulation, the legal responsibility for maintaining the records remains with the final-stage manufacturer.

However, the incomplete vehicle manufacturer, or any intermediate vehicle manufacturer, may assume "legal responsibility for all duties and liabilities imposed on manufacturers by (the Act) with respect to the vehicle as finally manufactured . . ." (49 C.F.R. 568.7). In such a case, the responsibilities for maintaining the records required by the Act and the Tire Identification and Record Keeping Regulation will be assumed by the incomplete vehicle manufacturer, or any intermediate manufacturer, and the final-stage manufacturer will be relieved of all liability for maintaining the records.

We would also point out that the Tire Identification and Record Keeping Regulation was not meant to preclude the use of multiple designees for the maintenance of the required records. See the enclosed interpretation issued on May 28, 1971 (36 F.C. 9780).

ID: nht92-1.16

Open

DATE: 12/18/92

FROM: CHRISTOPHER J. DANIELS -- NELSON, MULLINS, RILEY & SCARBOROUGH

TO: PAUL JACKSON RICE -- CHIEF COUNSEL DEPARTMENT OF TRANSPORTATION, NHTSA

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 2-11-93 FROM JOHN WOMACK TO CHRISTOPHER J. DANIELS (A40; STD. 109; STD. 119; PART 574)

TEXT: I have recently inspected a tire manufactured in Canada, on which the DOT number had been obliterated with a cutting tool to the point that the DOT number is completely gone.

It is my belief that the tire was knowingly and improperly sold with the tire's DOT number removed. On this basis, would you or someone at the Department of Transportation advise on the following:

1. If it is illegal for a tire to be exported from Canada to the United States without a DOT serial number in violation of customs, UCC, or FMVSS regulations.

2. If it is illegal to sell, or use, a tire for highway use without a DOT serial number.

After reviewing FMVSS Nos. 109 and 119 and Part 574 regarding tire identification regulations, I have not been able to find language which specifically and clearly states that it is illegal to sell or use a tire for highway use without a DOT serial number, although that is my interpretation.

I inquire as to whether or not you can provide or assist me in locating any documentation which could address the above questions.

Your assistance will be greatly appreciated. Please call me if you would like to discuss this further.

ID: nht70-1.19

Open

DATE: 07/01/70 EST

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Department of California Highway Patrol

TITLE: FMVSR INTERPRETATION

TEXT: In response to your letter of July 9 to Mr. Toms I would like to make clear that the creation of the subcategory "mobile structure trailer" does not remove mobile homes towed on their own wheels from their original categorization under the Federal motor vehicle safety standards as trailers. This means that rule making actions applicable to "trailers" are also applicable to mobile homes unless there is specific language indicating that a Federal standard or portion thereof does not apply to a mobile structure trailer.

Therefore, in answer to your specific questions:

(a) Proposed Standards Nos. 119 and 120 would apply to trailers and therefore to mobile structure trailers.

(b) No proposal has been issued which would extend the Federal hydraulic brake standard, No. 105, to cover trailers. Therefore a State may adopt hydraulic brake requirements for mobile homes. However, we have issued a proposal (Docket No. 70-16; 35 F.R. 10456, June 26, 1970) which would establish requirements for "trailers equipped with air brake systems". If adopted, this new standard would preclude a state from adopting other than identical air brake requirements for mobile homes and other trailers. The point may be academic as it is my understanding that mobile homes, as a rule, are equipped with electric brakes.

ID: aiam2459

Open
Mr. Karl-Heinz Ziwica, Manager - Safety Engineering, BMW of North America, Inc., Montvale, NJ 07645; Mr. Karl-Heinz Ziwica
Manager - Safety Engineering
BMW of North America
Inc.
Montvale
NJ 07645;

Dear Mr. Ziwica: THis is in response to your October 29, 1976, request for confirmatio that a recent NHTSA interpretation regarding the buckle crush requirements of Standard No. 209 (as stated in a letter to Volvo dated August 31, 1976) is applicable to BMW seat belt buckles.; Our letter to Volvo stated that the existing S4.3(d)(3) buckl requirements are not applicable to buckles that are located between bucket seats and attached to the console or to the end of a rigid cable or bar.' This interpretation constitutes an explanation of S4.3(d)(3) as its provisions apply to all seat belt buckles regulated by the standard. The interpretation is not applicable only to Volvo belt buckles or to buckles produced by any other individual manufacturer. It is the responsibility of each manufacturer to determine, in the first instance, whether or not his products fall within any standard's provisions, including provisions that are explained by means of an interpretation.; I am enclosing a copy of our August 31, 1976, letter to Volvo for you information. As requested, we have withdrawn your petition for rulemaking.; Sincerely, Frank A. Berndt, Acting Chief Counsel

ID: nht71-2.35

Open

DATE: 04/30/71

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Hamill Manufacturing Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of March 16, 1971, in which you ask certain questions concerning a child booster seat that you plan to market. You describe the booster seat as a rectangle about 6 inches in height, tapering to 4 inches in the front, and state that it would be advertised for use by children under 50 pounds and would not be designed to fall into the category of child seating systems under Standard No. 213. You also state that your engineers feel a booster chair will "definitely help more five, six and seven year old children to use seat belts simply because these children will be able to see out of a vehicle."

While you state that the booster seat "would not be designed to fall into the category of child seating systems under Standard No. 213," it is not clear from your description of the device that this is actually the case. If you wish an opinion on this matter, we will provide one, but to do so we will need some additional information. Specifically, we will need to know if the booster seat is to be designed or advertised for use with the vehicle seat belts, and if so, how it will be so designed or advertised.

The questions you ask concerning the booster seat are: (1) Can we set a minimum of 50 or 60 pounds? (2) Exactly what is the maximum child weight covered under MVSS #213? and (3) What recommended weight can we advertise as a minimum for our booster seat?

The answers to these questions do not depend on whether the standard applies to your booster seat. If the device is a child seating system, Standard No. 213 does not specify the minimum or maximum heights or weights for children who may use it. Under the standard, it is up to the manufacturer to determine, based upon the design of each particular child seating system, the heights and weights of children for which he recommends the child seating system.

If the device is not a child seating system, the manufacturer is not required to recommend any heights or weights for children who can use it. Should he choose to do so, however, the heights and weights recommended must be consistent with the safe use of the device.

ID: nht95-2.88

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 19, 1995

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Mary J Gazich -- Owner - Clever Kids, Inc.

TITLE: NONE

ATTACHMT: ATTACHED TO 3/23/95 LETTER FROM MARY J. GAZICH TO PHILLIP RECHT (OCC 10327)

TEXT: Dear Ms. Gazich:

This responds to your letter asking about how this agency's regulations might apply to your product, the "Smart Rider." In your letter, you described the Smart Rider as a "new automobile accessory for children." It is a vinyl seat back protector that sli ps over one or both of the front seats and secured, we assume, with the two 3/4 inch elastic bands.

The answer to your question is that there are no standards that apply directly to the Smart Rider, but there are Federal requirements that may affect it. I summarize below the relevant safety standards and laws you should consider.

As you recognized in your letter, the Smart Rider is an accessory, a type of motor vehicle equipment under our regulations. As a manufacturer of motor vehicle equipment, you are subject to the requirements in sections 30118-30122 of Title 49 of the U.S. Code concerning the recall and remedy of products with defects related to motor vehicle safety. In the event that the manufacturer or NHTSA determines that the product contains a safety related defect, the manufacturer would be responsible for notifyin g purchasers of the defective equipment and remedying the problem free of charge.

NHTSA has not issued any standards for an accessory such as the Smart Rider. For that reason, you should not place any label on your packaging to the effect that it meets Federal standards.

Although no standards apply directly to the Smart Rider, its installation may affect vehicle compliance with certain safety standards. NHTSA has issued a safety standard (Standard No. 201, Occupant protection in interior impact) that requires, among oth er things, that seat backs have a certain amount of cushioning to provide protection when struck by the head of rear seat passengers during a crash. Installation of your product on the back of front seats could have an impact on compliance with that sta ndard. If the vinyl of the Smart Rider is stiff enough, it might distribute the impact of the occupant's head over a larger area of the seat back than the vehicle manufacturer intended. As a result, the foam in the seat back might not compress as deepl y as the manufacturer intended, and the requisite amount of cushioning might not be achieved. We do not know how stiff the vinyl is, and this may not be a problem, but it is something of which you should be aware.

Another standard that you might want to consider is Standard No. 302, Flammability of interior materials. That standard requires that seat backs not burn or transmit a flame front across their surface at a rate of more than 4 inches per minute. If the S mart Rider were installed as part of a new vehicle, it would be considered part of the seat back.

Which legal requirements apply depend to some extent on how your product is marketed. If your product were installed by a vehicle manufacturer as original equipment, the vehicle manufacturer would have to certify that the vehicle with the Smart Rider in stalled complies with all FMVSS's, including Standards No. 201 and 302. In addition, although we recognize it would be unlikely that your product would be installed by a motor vehicle manufacturer, distributor, dealer or repair business, section 30122(b ) of title 49 prohibits those commercial businesses from "knowingly mak[ing] inoperative any part of a device or element of design installed on or in a motor vehicle . . . in compliance with an applicable Federal motor vehicle safety standard . . ." For instance, compliance with Standard No. 201 might be degraded if the Smart Rider were mounted in front of rear seat passengers. Any violation of this "make inoperative" prohibition would subject the installer to a potential civil penalty of up to $ 1,000 for each violation.

The "make inoperative" prohibition does not apply to modifications that vehicle owners make to their own vehicles. Thus, our standards would not apply in situations where individual vehicle owners install the Smart Rider in their own vehicles, even if t he installation were to result in the vehicle no longer complying with the safety standards. However, NHTSA encourages vehicle owners not to degrade any safety device or system installed in their vehicles. In addition, individual vehicle owners may mak e to their vehicles, so you might wish to consult State regulations to see whether the Smart Rider would be permitted.

I want to emphasize that NHTSA has not made a determination regarding the safety of the Smart Rider. NHTSA has not done any testing of your product. I am merely informing you of the applicable law and identifying a few potential problem areas for your consideration.

I hope this information is helpful. I am also enclosing a copy of a fact sheet titled "Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment." If you have any further questions about NHTSA's safety standards, please feel free t o contact Mr. Atelsek of my staff at this address or by telephone at (202) 366-2992.

ID: 10829-1

Open

Ms. Mary J Gazich
Owner - Clever Kids, Inc.
4091 Vermont Avenue
Eagan, MN 55123

Dear Ms. Gazich:

This responds to your letter asking about how this agency's regulations might apply to your product, the "Smart Rider." In your letter, you described the Smart Rider as a "new automobile accessory for children." It is a vinyl seat back protector that slips over one or both of the front seats and secured, we assume, with the two 3/4 inch elastic bands.

The answer to your question is that there are no standards that apply directly to the Smart Rider, but there are Federal requirements that may affect it. I summarize below the relevant safety standards and laws you should consider.

As you recognized in your letter, the Smart Rider is an accessory, a type of motor vehicle equipment under our regulations. As a manufacturer of motor vehicle equipment, you are subject to the requirements in sections 30118-30122 of Title 49 of the U.S. Code concerning the recall and remedy of products with defects related to motor vehicle safety. In the event that the manufacturer or NHTSA determines that the product contains a safety related defect, the manufacturer would be responsible for notifying purchasers of the defective equipment and remedying the problem free of charge.

NHTSA has not issued any standards for an accessory such as the Smart Rider. For that reason, you should not place any label on your packaging to the effect that it meets Federal standards.

Although no standards apply directly to the Smart Rider, its installation may affect vehicle compliance with certain safety standards. NHTSA has issued a safety standard (Standard No. 201, Occupant protection in interior impact) that requires, among other things, that seat backs have a certain amount of cushioning to provide protection when struck by the head of rear seat passengers during a crash. Installation of your product on the back of front seats could have an impact on compliance with that standard. If the vinyl of the Smart

Rider is stiff enough, it might distribute the impact of the occupant's head over a larger area of the seat back than the vehicle manufacturer intended. As a result, the foam in the seat back might not compress as deeply as the manufacturer intended, and the requisite amount of cushioning might not be achieved. We do not know how stiff the vinyl is, and this may not be a problem, but it is something of which you should be aware.

Another standard that you might want to consider is Standard No. 302, Flammability of interior materials. That standard requires that seat backs not burn or transmit a flame front across their surface at a rate of more than 4 inches per minute. If the Smart Rider were installed as part of a new vehicle, it would be considered part of the seat back.

Which legal requirements apply depend to some extent on how your product is marketed. If your product were installed by a vehicle manufacturer as original equipment, the vehicle manufacturer would have to certify that the vehicle with the Smart Rider installed complies with all FMVSS's, including Standards No. 201 and 302. In addition, although we recognize it would be unlikely that your product would be installed by a motor vehicle manufacturer, distributor, dealer or repair business, section 30122(b) of title 49 prohibits those commercial businesses from "knowingly mak[ing] inoperative any part of a device or element of design installed on or in a motor vehicle ... in compliance with an applicable Federal motor vehicle safety standard . . ." For instance, compliance with Standard No. 201 might be degraded if the Smart Rider were mounted in front of rear seat passengers. Any violation of this "make inoperative" prohibition would subject the installer to a potential civil penalty of up to $1,000 for each violation.

The "make inoperative" prohibition does not apply to modifications that vehicle owners make to their own vehicles. Thus, our standards would not apply in situations where individual vehicle owners install the Smart Rider in their own vehicles, even if the installation were to result in the vehicle no longer complying with the safety standards. However, NHTSA encourages vehicle owners not to degrade any safety device or system installed in their vehicles. In addition, individual States have the authority to regulate modifications that individual vehicle owners may make to their vehicles, so you might wish to consult State regulations to see whether the Smart Rider would be permitted.

I want to emphasize that NHTSA has not made a determination regarding the safety of the Smart Rider. NHTSA has not done any testing of your product. I am merely informing you of the applicable law and identifying a few potential problem areas for your consideration.

I hope this information is helpful. I am also enclosing a copy of a fact sheet titled "Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment." If you have any further questions about NHTSA's safety standards, please feel free to contact Mr. Atelsek of my staff at this address or by telephone at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

Enclosure

ref:VSA d:5/19/95

1995

ID: nht93-2.1

Open

DATE: 03/01/93

FROM: THOMAS C. BALOGA -- MANAGER, SAFETY ENGINEERING, MERCEDES - BENZ

TO: JOHN WOMACK -- ACTING CHIEF COUNSEL, NHTSA

COPYEE: JERRY SONOSKY -- HOGAN & HARTSON

TITLE: LONGER SEAT BELT FOR OVER-SIZE MERCEDES-BENZ OWNER

ATTACHMT: ATTACHED TO LETTER DATED 3-10-93 FROM JOHN WOMACK TO THOMAS C. BALOGNA (A40; VSA 108 (a)(2)(A); STD. 209)

TEXT: This refers to my telephone discussion with Ed Glancy on March 1, 1993 concerning a longer seat belt.

Mercedes-Benz of North America, Inc. has been contacted by the owner of a Mercedes-Benz car who cannot use the driver-side seat belt because of his large body size (approx. 500 lbs). Since our special order 12 inch longer belt is still too short, our factory has supplied a 30 inch longer-than-standard seat belt for installation in this man's car. The extra-long belt assembly will not comply with the following aspects of Standard 209:

- seat belt will not completely roll-up into B-pillar due to excessive webbing on spool;

- seat belt not tested for retraction spring durability therefore may not pass the retractor cycle test;

- no certification label is attached.

We ask that you please advise us as soon as possible whether NHTSA will, under these circumstances, exercise appropriate discretion in non-enforcement of Standard 209 for this special seat belt installation. This discretion would be similar to Chief Counsel interpretations concerning non-enforcement of Standards when special equipment for handicapped drivers is installed. Without this action from you, the man will not be protected by a seat belt. We know that requests for extra long seat belts are likely to continue and we ask that you please advise us whether Mercedes-Benz of North America, Inc. needs to advise you of each and every special installation or whether it is sufficient for us to keep appropriate records of the VIN etc. It is our intention to advise the owner to have the original belt re-installed before selling the car.

Thank you for your quick response.

ID: nht92-3.31

Open

DATE: 10/02/92

FROM: MARK W. STEVENS -- CHAIRMAN, SEATMORE

TO: PAUL JACKSON RICE -- CHIEF COUNSEL, NHTSA

ATTACHMT: ATTACHED TO LETTER DATED 11-13-92 FROM PAUL J. RICE TO MARK W. STEVENS (A40; STD. 207; STD. 208; STD. 209; STD. 210; STD. 302; VSA 108

TEXT: We are in the process of designing and manufacturing a after market 3rd rear facing seat for the Ford Taurus and Mercury Sable station wagons 1986-1993.

The Product information contained in these document is proprietary and confidential trade secret information of Seatmore. We ask that this information be kept confidential.

We have asked Johnson Safety in California to manufacture the 3rd seat described in these documents, they have contacted James Gilkey in Code Enforcement Division. Mr. Gilkey suggested that we contact you with the following questions in order to know proper testing requirements.

1. Does the aftermarket 3rd rear facing station wagon system have to be tested in compliance with FMVSS 207, 209, & 210?

2. The seat belt anchorages are Ford factory anchorages built into the car at the factory and designed specifically for the Ford factory 3rd seat and seat belts. We will be using the same anchorages with aftermarket seat belts already in compliance. Is a test required for this system?

3. If testing is required, must they be specifically Static Tested or Dynamic Crash Tested?

I have enclosed pictures with descriptions of the seat and Ford factory mountings for your review.

Please feel free to call if you have questions or need further information. We are ready to take this product to the auto aftermarket and we would appreciate your review and response as soon as possible.

ID: nht92-9.57

Open

DATE: January 7, 1992

FROM: Thomas J. Magnan -- Sergeant, Traffic Safety Division, Metropolitan Police Department, City of St. Louis, Mo.

TO: Taylor Vinson -- Legal Counsel, NHTSA

TITLE: Re: "Hella" brand Position Indicator Lamp

ATTACHMT: Attached to letter dated 2/11/92 from Paul Jackson Rice to Thomas Magnan (A39; Std. 108)

TEXT:

I saw a demonstration of the new "Hella" brand Position Indicator Lamp at a safety show I attended in British Columbia, in September 1991.

I have since contacted a Hella distributor in St. Louis, Mo with questions on where this may be purchased and the price of the item. He informs me that Hella of Germany has told him that to sell or install this item on a vehicle in the United States is against the law, as it has not as yet been approved for sale or use in this country. I then contacted a Mr. Scott Toivanen at 1-604-687-7779 with the Canadian Distributor OBIRON ENTERPRISES INC. Mr. Toivanen informed me that he has attended meeting with representatives from this country, specifically NHTSA and DOT-OMC, and both agencies approved of this device, so long as the maximum vehicle width was not exceeded. I contacted Mr. Kevin Cavey at NHTSA, who was reportedly at one of these meetings and Mr. Cavey told me he didn't know what I was talking about, and suggested I write to you.

Please advise as to whether this item may be used on vehicles in the United States, providing the maximum vehicle width of 102.36 inches is not exceeded.

Enclosed please find related information on the product.

Attachments (Text and graphics omitted):

Brochure entitled IPS Corporation Introduces the Position Indicator Lamp. Indicates that the lamp is distributed in Alberta and British Columbia by Obiron Enterprises Inc.

Copy of a letter from Claus Bergmeier, President of International Product Specialities (IPS), announcing a new safety marker lamp for commercial vehicle application.

Copy of a report, dated 2/5/91, from the Canadian Standards Association, containing the results of examinations and tests of the IPS position indicator lamp. Demonstrates compliance with applicable SAE standards.

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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