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
| Interpretations | Date |
|---|---|
| search results table | |
ID: aiam4017OpenMr. K. Douglas Scribner, President, Mini City Ltd., 876 Turk Hill Road, Fairport, NY 14450; Mr. K. Douglas Scribner President Mini City Ltd. 876 Turk Hill Road Fairport NY 14450; Dear Mr. Scribner: This responds to your recent letter seeking an interpretation o Standard No. 109, *New Pneumatic Tires--Passenger Cars* (49 CFR S571.109). Specifically, you were interested in learning whether that standard applies to tires for use on 'antique and classic automobiles.' You stated that your firm deals in tires which are authentic replacement tires for antique and classic cars, and that none of those tires has ever been marked with a DOT number. Standard No. 109 requires that all new pneumatic tires for use on passenger cars manufactured after 1948 be marked with DOT numbers, among other things, and there is no exception to this requirement for tires designed for 'classic' cars.; It is unclear when you refer to a 'DOT number' whether you ar referring to just the tire identification number, which is required to appear on all new tires for use on passenger cars manufactured after 1948 by 49 CFR Part 574, *Tire Identification and Recordkeeping*, or that identification number together with the symbol 'DOT.' The DOT symbol is a certification by the tire manufacturer that the tire complies with all the requirements of Standard No. 109. I have enclosed copies of both Standard No. 109 and Part 574 for your information.; In any event, Standard No. 109 applies to *all* new pneumatic tires fo use on passenger cars manufactured after 1948. Section S4.3.1 of the standard requires the DOT symbol to be permanently marked on the tire, while section S4.3.2 requires the tire identification number assigned to a manufacturer in accordance with Part 574 to be permanently marked on the tire. Standard No. 109 contains no provisions making an exception to these requirements.; Accordingly, if the antique and classic cars to which you refer wer manufactured in or before 1948, the tires are not subject to Standard No. 109 or Part 574. Sale of such tires would not violate any of this agency's requirements.; If, however, the tires are designed for use on cars manufactured afte 1948, the tires must comply with all requirements of Standard No. 109, including the requirements to have a DOT symbol and a tire identification number marked permanently on the sidewall. If you sell tires which are subject to, but do not comply with, the requirements of Standard No. 109, you would violate section 108(a)(1)(A) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1397(a)(1)(A)). Section 109 of that Act (15 U.S.C. 1398) specifies a maximum civil penalty of $1,000 for each violation of section 108, and this agency would consider each sale of a noncomplying tire to be a separate violation.; If you need any further information on this subject, please contac Steve Kratzke of my staff at this address or by telephone at (202) 426-2992.; Sincerely, Erika Z. Jones, Chief Counsel |
|
ID: aiam1645OpenMr. Byron Crampton, Manager of Engineering Services, Truck Body and Equipment Association, Inc., 5530 Wisconsin Avenue, Suite 1220, Washington, DC 20015; Mr. Byron Crampton Manager of Engineering Services Truck Body and Equipment Association Inc. 5530 Wisconsin Avenue Suite 1220 Washington DC 20015; Dear Mr. Crampton: This responds to your October 3, 1974, questions whether the exemptio for 24,000-pound axle vehicles from Standard No. 121, *Air brake systems*, until September 1, 1976, applies to fire fighting vehicles, and whether a tandem axle assembly consists of two 'axle systems' for purposes of our definition of 'Gross axle weight rating.'; The answer to both of your questions is yes. A fire fighting vehicl would qualify for exemption until 1976 if any of its axles has a gross axle weight rating of 24,000 pounds or more.; A tandem axle assembly, which we understand to mean a running rea assembly consisting of two axles and associated components, comprises two 'axle systems.' As we pointed out in the preamble to Notice 2 of Docket No. 74- 10, the term 'axle system' is used only to avoid confusion in situations where a suspension system does not employ an axle (39 FR 17550, May 17, 1974).; Yours truly, Richard B. Dyson, Acting Chief Counsel |
|
ID: aiam3678OpenMr. T. J. Brown, Mohawk Rubber Company, Roanoke, VA 24017; Mr. T. J. Brown Mohawk Rubber Company Roanoke VA 24017; Dear Mr. Brown: This is in response to your March 28, 1983, letter to Roger Fairchil of this office, requesting confirmation of your understanding of the effective dates for the recent suspension of treadwear grading under this agency's Uniform Tire Quality Grading Standards.; Your understanding of the effective dates is correct. Tires produced i molds manufactured on or after August 8, 1983, must have the new grading format which excludes treadwear information. Tires produced in molds manufactured before that date may either use the new format as soon as feasible, to minimize the dissemination of misleading information with regard to tire treadwear.; With regard to labels, the requirement that such labels must contai information regarding treadwear grades was suspended effective February 7, 1983. The preamble to the final rule states that manufacturers will be permitted to exhaust inventories of labels which were in existence as of the date of the suspension. Thereafter, manufacturers should begin using labels without treadwear information.; If you have further questions on this matter, please feel free t contact us.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam0957OpenMr. A. P. Hoynck Van Papendrecht, Technical External Relations, Van Doorne's Automobielfabrieken N. V., Endhoven, Holland; Mr. A. P. Hoynck Van Papendrecht Technical External Relations Van Doorne's Automobielfabrieken N. V. Endhoven Holland; Dear Mr. Van Papendrecht:#This is in reply to your letter of Novembe 12, 1972, about compliance of DAF cars with Federal Motor Vehicle Safety Standard No. 102.#Your question concerns the interpretation of paragraph S3.1.2. From your description in the letter and the description in the owner's manual, only one forward drive position is provided and engine braking can be achieved by actuating the transmission low ratio control switch. Under the conditions described above, the Variomatic transmission in DAF cars is not in violation with paragraph S3.1.2 of Standard No. 102. However, it appears that you do not comply with certain other paragraphs of the standard. For example, paragraph S3.1.1 requires that 'A neutral position shall be located between forward drive and reverse positions ....' and paragraph S3.1.3 requires that 'The engine starter shall be inoperative when the transmission shift lever is in a forward or reverse drive position.'#The DAF 66 owners manual dated September 1972, also indicates non-compliance with other standards, for example, 101, *Control Location, Identification and Illumination*, 114, *Theft Protection*, 115, *Vehicle Identification Number*, etc. It is recommended that all standards and regulations be checked for compliance.#A copy of 'Where to Obtain Motor Vehicle Safety Standards and Regulations' is enclosed for your review and information.#Sincerely, E. T. Driver, Director, Office of Operating Systems, Motor Vehicle Programs; |
|
ID: aiam4447OpenMr. Jan Peter Kryger Vice President, Sales and Marketing Quickwheel, Inc. P.O. Box 39l Cos Cob, Connecticut 06830; Mr. Jan Peter Kryger Vice President Sales and Marketing Quickwheel Inc. P.O. Box 39l Cos Cob Connecticut 06830; "Dear Mr. Kryger: This responds to your letter asking whether an Federal safety standards apply to your product called 'Quickwheel' and whether you need approval from the Department of Transportation to market the product. You indicated that Quickwheel is similar to a roller skate and can be placed under a flat tire in a few seconds, enabling the driver to go on to a service station. You stated that the device has three little wheels and has been 'thoroughly tested' in Germany. The National Traffic and Motor Vehicle Safety Act (Safety Act) authorizes the National Highway Traffic Safety Administration (NHTSA) to issue safety standards for new motor vehicles and new motor vehicle equipment. All motor vehicles and items of motor vehicle equipment manufactured or imported for sale in the United States must comply with all applicable safety standards. NHTSA does not provide approvals of motor vehicles or equipment. The Safety Act places the responsibility on the manufacturer to ensure that its vehicles or equipment comply with applicable requirements. The following represents our opinion based on the facts provided in your letter. NHTSA does not have any safety standards covering a roller-skate-like device intended to be placed under a flat tire in order to enable the driver to continue driving. However, should a safety-related defect be discovered in your device, whether by the agency or yourself, you as the manufacturer would be required by the Safety Act to notify purchasers and provide a remedy for the defect. While no Federal motor vehicle safety standards apply to Quickwheel, we note that the performance of the device is relevant to safety in many of the same respects as tires, which are covered by safety standards. Given this potential safety significance, we urge you to carefully review whether the testing conducted in Germany covered the full range of real-world driving conditions and experiences that may be encountered by Quickwheel, and if not, to conduct such additional testing and/or analysis as may be necessary to ensure that the product will perform in a safe manner. You also asked for an explanation of the Code of Federal Regulations. You will find such an explanation on the last page of an enclosed information sheet entitled 'Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment.' You may also find other parts of the information sheet to be of interest. Sincerely, Erika Z. Jones Chief Counsel Enclosure"; |
|
ID: aiam3382OpenMr. T. Shimada, Senior Technical Manager, MMC Services Inc., 3000 Town Center, Suite 1960, Southfield, MI 48075; Mr. T. Shimada Senior Technical Manager MMC Services Inc. 3000 Town Center Suite 1960 Southfield MI 48075; Dear Mr. Shimada: This responds to your letter of October 14, 1980, regarding the warnin devices required by Safety Standard No. 114, *Theft Protection*, and Safety Standard No. 208, Occupant Crash Protection. You ask whether the sound of a voice repeating the phrase 'please pull out the ignition key' or 'please fasten seat belt' at 2-3 second intervals could be used to satisfy the requirements of Standard No. 114 and Standard No. 208. You also ask whether a buzzer or chime that signals an unfastened seat belt or the presence of the key in the ignition could also be used to give the driver other warnings, such as turning off the headlights.; Standard No. 114 does not specify the nature of the warning that mus be given to the driver in the event that the ignition key is left in the locking system. Thus the system you describe would comply with the rule. Notre that the signal must be activated whenever the key has been left in the ignition and the driver's door is opened.; Standard No. 208 requires that the driver's seating position b equipped with a warning system that activated a continuous or intermittent audible signal for a period of not less than four (4) seconds and not more than eight (8) seconds. The signal must begin when the vehicle's ignition switch is in the 'on' or 'start' position and the driver's belt is not in use. If the system you have devised stops the warning only when the belt has been fastened, it would not comply with this rule. The signal must end within eight (8) seconds, irregardless(sic) of whether the driver's belt has been fastened. Regardless your specific question, an audible 'voice' signal would be permitted under the standard.; The buzzers or chimes that are installed in accordance with Standar No. 214 or Standard No. 208 may also be used to warn the driver of other conditions.; We hope you find this information helpful. Please contact this offic if you have any other questions.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam4650OpenMr. David G. Gould Legislation Department Lotus Engineering Hethel, Norwich, Norfolk NR14 8EZ ENGLAND; Mr. David G. Gould Legislation Department Lotus Engineering Hethel Norwich Norfolk NR14 8EZ ENGLAND; "Dear Mr. Gould: Thank you for your letter asking whether a worl manufacturer identifier (WMI) assigned by the Society of Automotive Engineers (SAE) pursuant to a contract with this agency may be deleted from SAE's register of assigned WMIs upon request of a foreign national governmental agency, but without the consent of the holder of the WMI. Absent some extraordinary circumstances, the answer to your question is no. 49 CFR Part 565, Vehicle Identification Number - Content Requirements, sets forth format and content requirements for vehicle identification numbers (VINs). Section 565.4(a) specifies that the first three characters of the VIN shall be the manufacturer's WMI, which is 'assigned in accordance with /565.5(c) of this part.' Section 565.5(c) specifies that the SAE assigns WMIs to vehicle manufacturers under contract with the National Highway Traffic Safety Administration (NHTSA). No provision in NHTSA's regulations sets forth any procedures for deleting assigned WMIs from the SAE register upon the request of any party, even the manufacturer assigned the WMI. Similarly, no provision in the contract specifically addresses the issue of deleting assigned WMIs for any reason. In its contract with NHTSA, SAE has agreed to 'furnish the facilities, materials, personnel and services necessary to accomplish the work...' We contacted the SAE's WMI Coordinator to learn how they have handled this situation in the past. We were informed that the WMIs are assigned by the SAE for an indefinite period with no express provision for revocation of the assignment. There have been a few isolated instances in which the party to whom a WMI was assigned has contacted SAE and asked that the WMI assignment be revoked. In those instances, the SAE has granted the manufacturer's request but the revoked WMI is never reassigned to another manufacturer. To date, SAE has never been asked to delete an assigned WMI by any party other than the manufacturer to whom the WMI was assigned. If a situation arose in which the SAE was asked to delete an assigned WMI without the knowledge and consent of the manufacturer to whom the WMI was assigned, the SAE assures us that they would not act on the request without consulting this agency. If and when we are ever consulted by SAE for our opinion on how to handle such a request, we would carefully consider the circumstances of the particular case before advising SAE on how to respond to the request. As a general matter, however, NHTSA does not favor the deletion of assigned WMIs for any reason. Sincerely, Stephen P. Wood Acting Chief Counsel"; |
|
ID: aiam3195OpenMr. Brian Gill, Manager, Certification Department, American Honda Motor Co., Inc., P.O. Box 50, 100 W. Alondra Boulevard, Gardena, California 90247; Mr. Brian Gill Manager Certification Department American Honda Motor Co. Inc. P.O. Box 50 100 W. Alondra Boulevard Gardena California 90247; Dear Mr. Gill: This is in response to your letter of November 18, 1979, requesting a interpretation as to whether the VIN plate samples you enclosed with your letter comply with the requirements of Standard No. 115, *Vehicle identification number*.; You enclosed two proposed VIN plates in your letter, one fo automobiles and one for motorcycles.The VIN plates themselves and the pre-printed lettering which appears on them seem to conform to the requirement of Standard No. 115. The lettering is clear and indelible, as required by S4.3, in that it cannot be removed without damage to the surface on which it is printed. Further, the plate when riveted to the vehicle would be considered to be permanently affixed in that it cannot be removed without damage (S4.3). The type face utilized for the lettering consists of capital, sans serif characters with a minimum height of 4 mm as required by S4.3.1.; The letters stamped on the automobile VIN plate 'SL5322AS000001', ca hardly be seen, and would not appear to meet the requirements of S4.3 and S4.4.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam1452OpenMr. J.K. White,Domi Racer Distributors, inc.,5218 Wooster Road,Cincinnati, Ohio 45226; Mr. J.K. White Domi Racer Distributors inc. 5218 Wooster Road Cincinnati Ohio 45226; Dear Mr. White:#This responds to your March 19, 1974, request to kno if aircraft hydraulic hose is suitable for motor vehicle use under Standard 106, *Brake hoses*.#Standard No. 106, *Brake hoses*, presently applies to hydraulic brake hose for use in passenger cars, and therefore sale of aircraft hydraulic hose for use in motorcycles is presently legal. However, Standard 106 has been recently amended to require extensive performance testing and labeling of all motor vehicle brake hose manufactured after September 1, 1974. Sale of an aircraft hose manufactured after that date which has not been certified to conform to Standard 106 would violate S108 (a)(1) of the National Traffic and Motor Vehicle Safety Act of 1966. This means that the hose must be properly tested for conformity to the standard, and labeled according to the standard, before it can be sold as motor vehicle hose.#Yours truly,Richard B. Dyson,Assistant Chief Counsel; |
|
ID: aiam4200OpenMr. W. Alex Cantrell, President, C&A Control Systems, Inc., 7117 Commercial Park Drive, Knoxville, TN 37918; Mr. W. Alex Cantrell President C&A Control Systems Inc. 7117 Commercial Park Drive Knoxville TN 37918; Dear Mr. Cantrell: This responds to your letter regarding the LA-Z-START, a remote contro device which you manufacture for starting automobiles. You ask whether your device is compatible with Standard No. 114, *Theft Protection*. I regret the delay in responding to your letter.; For your information, this agency does not approve motor vehicles o motor vehicle equipment. Instead, NHTSA relies on the self-certification process in the National Traffic and Motor Vehicle Safety Act of 1966, as amended, which requires each manufacturer to certify that a motor vehicle or item of motor vehicle equipment complies with all applicable safety standards.; The product information enclosed with your letter indicates that thi device permits a person to use a remote control device to send a coded signal to start or stop a vehicle engine up to 500 feet away. Your device will shut off the engine immediately if any of the following events occur: (1) the transmission is removed from the park position, (2) the brake pedal is depressed, (3) the engine overspeeds or overheats, or (4) the hood is raised. In addition, the device will not start the engine if the transmission is in forward or reverse gear. The device automatically shuts off the engine after 12 to 14 minutes running time and allows remote shut-off at any time.; Standard No. 114 requires that passenger cars as well as trucks an multipurpose passenger vehicles with a gross vehicle weight rating of 10,000 pounds or less have a key locking system. When the key is removed, the system must prevent normal activation of the vehicle's engine and prevent either steering or forward self-mobility or both. You state that starting a vehicle with your device does not permit normal activation of the vehicle's engine and either forward motion or steering until the key is inserted into the ignition and turned to the on position. Therefore, the question is whether your device, which permits activation of the engine when the ignition key is removed, permits 'normal activation' of the vehicle.; In previous interpretations, the agency has determined that automotiv remote starting devices with characteristics similar to yours were outside the concept of 'normal activation.' These characteristics have included automatic deactivation of the remotely started engine when a vehicle door is opened, maintenance of the steering column or gear shift locking feature until the ignition key is inserted in the vehicle, and automatic deactivation of the remotely started engine after 15 minutes unless the key is inserted into the ignition.; Your device apparently has some of these same characteristics, as wel as other automatic deactivation features which are comparable in nature. Therefore, we conclude that your device does not conflict with the requirements of Standard No. 114, since it does not permit normal activation of the engine without the ignition key.; Although not related to compliance with Standard No. 114, the agency i concerned about the possibility that a child could accidentally press the transmitter button on your device and, thus, start a car by remote control. This situation could clearly raise safety problems. Therefore, we suggest that you add language to the purchasers' instructions making them aware of this possibility and urging them to take precautions to avoid use of the product by anyone who is not authorized to drive the car.; I hope this information is helpful to you. Sincerely, Erika Z. Jones, Chief Counsel |
|
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.