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 |
|---|---|
ID: aiam2744OpenMr. Emil M. Mrak, 602 Cordova Place, Davis, CA 95616; Mr. Emil M. Mrak 602 Cordova Place Davis CA 95616; Dear Mr. Mrak: This is in reply to your letter of December 12, 1977, to Secretary o Transportation, Mr. Brock Adams, concerning the seat belts in your automobile.; Federal Motor Vehicle Safety Standard No. 208, Occupant Cras Protection, requires that the distance between the lap-shoulder belt intersection and the vertical center line of a 50th percentile (164 pounds, 5 feet 8 inches) adult male occupant must be at lease six inches when the seat is in its rearmost position. The purposes of this requirement is to reduce the risk of the occupant 'submarining' out from under the belt and to reduce the possibility of the shoulder belt pulling the lap belt up onto the abdomen where it could cause serious injury in a crash.; The possibility of submarining increases as the intersection of th lap-shoulder belt is moved toward the occupant's centerline and/or as seat cushion rigidity is reduced. In other words, the closer the intersection of the lap-shoulder belt is to the centerline of the occupant, and the softer the seat, the more the danger of 'submarining' in a crash. The standard does not limit the maximum distance from the occupant's centerline to the lap- shoulder belt intersection because of varying degrees of seat rigidity and installation configurations. Thus, contrary to what you may have been told, manufacturers who provide belt systems with distances greater than six inches do so by choice and not because they are required to do so by Federal standards.; Thank you for informing us of your problem. Sincerely, Elwood T. Driver, Acting Associate Administrator fo Rulemaking; |
|
ID: aiam3856OpenWilliam Richard Alexander, Pupil Transportation Section, Maryland State Department of Education, 200 West Baltimore Street, Baltimore, MD 21201-2595; William Richard Alexander Pupil Transportation Section Maryland State Department of Education 200 West Baltimore Street Baltimore MD 21201-2595; Dear Mr. Alexander: This responds to your March 20, 1984, letter to the National Highwa Traffic Safety Administration (NHTSA), concerning the Federal school bus safety standards administered by this agency. You asked three questions regarding passenger seating in school buses and the classification of vehicles as school buses.; Specifically, your questions asked: >>>(a) There are 9 students plus the driver, for a total of 10 people in a school bus. For purposes of the definition of a school bus, is the driver a passenger?<<<; Section 571.3 of the Code of Federal Regulations defines a 'school bus as a bus that transports children to or from school or related events. Our regulations further define 'bus' as a vehicle designed for carrying more than 10 persons. The driver is considered a 'person' under our regulations. Thus, it may be useful to remember that any vehicle that carries more than 10 *persons* is a bus. Your vehicle which seats 9 students plus the driver, for a total of 10 persons, would not be considered a school bus.; >>>(b) If a van is originally designed for 11 passengers plus a drive and, because the definition of a school bus, the school system desires to alter the number of seat spaces by removing seats so that the van will accommodate 9 pupils plus the driver, will this alteration in any way conflict with the definition of vehicle capacity? (I would assume that any structural changes would place liability in the event of accident attributable to that alteration on the local school system making the change.) <<<; In asking whether the alteration will 'conflict with the definition o vehicle capacity,' we assume that you are asking whether removing the seats of the vehicle changes the classification of that vehicle as a bus. Your letter is not clear whether it is a dealer who will be modifying the vehicle prior to its sale to the school system, after its sale to the school system, or whether the school itself will be modifying the bus after purchasing the vehicle. We will address these situations in our answer.; Altering an 11-passenger van by removing some of its seats so that i would no longer be of a passenger capacity that would classify it as a bus is, in theory, permissible. If a dealer makes such a modification before the vehicle is sold to you, it must attach an alterer's label in accordance with Part 567.7, *Certification*, of our regulations. Since the dealer would be changing the vehicle type from a bus to a multipurpose passenger vehicle, it must make sure that the vehicle complies with all of the standards applicable to that new vehicle type. This might be difficult since some different standards apply to multipurpose passenger vehicles than apply to buses.; If the modifications to the vehicle are made by a business such as garage after you purchase the vehicle, the persons modifying the vehicle must not knowing (sic) render inoperative the compliance of your vehicle with any applicable safety standard. Section 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act prohibits motor vehicle manufacturers, distributors, dealers and repair businesses from rendering inoperative equipment or designs that are incorporated in motor vehicles in compliance with the Federal motor vehicle safety standards. This means that a person in any of the above categories would not be permitted to destroy the vehicle's compliance with any safety standard by the removal of the seat.; The prohibition against rendering inoperative does not apply to a owner, such as a school or a state, which modifies its own vehicles. A school modifying its own vehicles need not assure that the vehicles comply with the Federal school bus safety standards. However, you are correct in assuming that your school could incur substantial tort liability in the event of an accident involving a vehicle that was not in compliance with the appropriate safety standards. This matter should be discussed with your insurance company and attorney. You should further determine whether your State law would prohibit the use of these vehicles to transport school children.; >>>(c) On a 60-passenger school bus, all of the seats except the thre rows in the front are removed. Each seat is 39 inches in width and is used to accommodate two high school pupils. The vehicle color is something other than yellow. A floor-to-ceiling barrier, with an emergency opening, is installed behind the three rows of seats. Supplies, materials, tools, equipment, etc., are transported in the rear of the vehicle with up to 12 youngsters plus the driver in the front portion. Given that all these factors exist at one time, will this vehicle be in conflict with any federal standards? If so, which ones?<<<; There are several areas of school bus safety which could be affected b the proposed modification of the vehicle. Since the vehicle will be carrying more than 10 persons, it is categorized as a bus, and classified by its use as a school bus. A threshold issue related to the question you asked concerns, again, the possibility that removing the bus seats will render inoperative the vehicle's compliance with the Federal school bus safety standards. The issue depends on whether it is a garage-type business that will be altering the bus, or the school. Modification of a safety system so that it no longer complies with all applicable safety standards in effect on the date of the vehicle's manufacture would be a violation of Section 108(a)(2)(A). As discussed earlier, this prohibition does not apply to an owner, such as a school or a state, which modifies its own vehicles. A school may make any modification that it chooses to its buses. Such action does not violate the Vehicle Safety Act or render the school subject to any penalty under the Act.; However, as you know, private liability might occur if th modifications took the vehicle out of compliance with the safety standard and a student was subsequently injured in one of the buses. Accordingly, the modifications you make should not negatively affect the compliance of your vehicle with the safety standards.; The removal of the bus seats does not appear likely to affect adversel your vehicle's compliance with the Federal safety standards. Those standards do not require the installation of any specific seats or any specified number of seats in school buses. Instead, the standards specify that certain requirements must be met for any seat that is installed. Therefore, if the bus complied with the requirements of the Federal school bus safety standards before its alteration, the proper removal of the seats would not affect the vehicle's compliance.; You propose to install a floor-to-ceiling barrier in the vehicle behin the three rows of seats. Your letter does not describe this barrier in detail, but states that it contains an emergency opening. We are concerned that this barrier would render the vehicle in noncompliance with the requirements for emergency exits found in FMVSS No. 217, *Bus Window Retention and Release*.; Standard No. 217 regulates the number and size of school bus emergenc exits and requires that the release mechanisms of those exits be readily accessible. The purpose of these requirements is to provide an easily operable, unobstructed school bus emergency exit. In the past, the agency has preempted a State requirement for a safety chain that would have been placed across an exit, because we viewed the chain as providing an obstruction to the opening. We have also interpreted the Standard to prohibit a ramp used for transporting the handicapped when the ramp partially blocked the rear emergency exit when it folded into the bus. Your letter did not describe in detail the floor-to-ceiling barrier in your bus and we are unable to form an opinion as to the compliance of the altered vehicle with Standard No. 217. However, if the barrier provides an impediment to the emergency exit then the alteration might conflict with FMVSS No. 217. Further, if the barrier conflicted with Standard No. 217, then it could not be added as aftermarket equipment by any manufacturer, dealer, or repair business, without rendering inoperative the compliance of the bus with the safety standard.; Finally, you indicated that the school bus would be a color other tha yellow. Highway Safety Program Standard No. 17 formerly permitted school vehicles carrying 16 or less students to or from school (i.e., 'Type II' school vehicles) to be marked, painted, and lighted in one of two ways. The buses could be either marked, painted, and lighted as school buses, or marked painted, and lighted differently than school buses. However, all school buses now must have the lighting of a school bus required under Federal Motor Vehicle Safety Standard No. 108, *Lamps, Reflective Devices, and Associated Equipment*. since all school buses must have the lighting of a school bus, under Highway Safety Program Standard No. 17 they also must have the painting and marking of a school bus.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam0329OpenMr. Yasunobu Mitoya, Project Manager, Designing Division, Toyo Kogyo Co. Ltd. 6047 Fuchu-Machi, Aki-Gum, Hiroshima, Japan; Mr. Yasunobu Mitoya Project Manager Designing Division Toyo Kogyo Co. Ltd. 6047 Fuchu-Machi Aki-Gum Hiroshima Japan; Dear Mr. Mitoya: This is in reply to your letter of April 6, 1971, requesting a interpretation of section S7 of Standard No. 208, Occupant Crash Protection.; Your question concerns the requirement of S7.1.2 that the intersectio of the upper torso belt with the lap belt shall be at least 6 inches from the occupant's front vertical centerline. As we understand your question, you have asked whether this 6-inch distance must be achieved by using an inboard belt segment of fixed length, or whether a manual adjusting device may be used that will permit lengthening of the inboard belt segment when the seat is moved forward.; It is the intent of section S.1.2 to require an intersection point tha cannot be adjusted so that it is less than 6 inches from a 50th percentile male occupant's centerline. We are considering a possible amendment to the standard to clarify this intent.; Please advise us if further explanation is needed. Sincerely, Robert L. Carter, Acting Associate Administrator, Moto Vehicle Programs; |
|
ID: aiam2314OpenHonorable Philip A. Hart, United States Senate, Washington, DC 20510; Honorable Philip A. Hart United States Senate Washington DC 20510; Dear Senator Hart: This is in response to your letter of May 11, 1976, forwarding petition for reconsideration of the recently issued Part 581 bumper standard from Gulf + Western Manufacturing Company. You ask that the agency provide Gulf + Western with cost-benefit data upon which the bumper standard was based and also supply you with any available information justifying promulgation of the standard.; All of the data upon which the National Highway Traffic Safet Administration (NHTSA) based the Part 581 bumper standard, including several cost- benefit analyses, are in the public docket and available for public examination. A series of proposals preceded the issuance of the final rule, and information submitted in response to each of these proposals was closely reviewed and taken into account in reaching the finally adopted provisions.; Although we are prepared to provide you with the data that led to th issuance of the final rule, the volume of information is tremendous. Cost- benefit data are contained not only in several agency-prepared studies, but also in a large number of submissions from the automotive industry and other interested parties. I am therefore only enclosing the major agency studies on the costs and benefits of the bumper standard. You should note, however, that a considerable amount of additional information was considered. I am also enclosing copies of the *Federal Register* notices that preceded promulgation of the Part 581 standard. The preambles of these notices will give you an overview of the information upon which the agency based its bumper regulation.; It is the NHTSA's policy to issue a notice of action taken on petition for reconsideration within 120 days after publication of the final rule, unless action within that time is impracticable. I assure you that Gulf + Western's comments and the information contained in all of the petitions for reconsideration will receive thorough consideration. The agency's response to the petitions will be published in the *Federal Register*.; Sincerely, Frank Berndt, Acting Chief Counsel |
|
ID: aiam1492OpenMr. Peter Dakin, 733 spartan Drive, Rochester, MI 48063; Mr. Peter Dakin 733 spartan Drive Rochester MI 48063; Dear Mr. Dakin: This is in response to your letter of May 4, 1974, requestin information concerning Federal safety standards applicable to the assembly of kit cars.; The National Traffic and Motor Vehicle Safety Act of 1966 prohibits th manufacture for sale or introduction into interstate commerce of any motor vehicle that does not comply with all applicable Federal motor vehicle safety standards. therefore, if the vehicle you are building is going to be used as a means of transportation on the road, it must be certified as conforming with all applicable safety standards. The mere use of a vehicle on public highways constitutes an introduction into interstate commerce and is prohibited unless compliance with the safety standards has been achieved.; Part 567.4(g)(1)(ii) of the certification regulations provides th producer of the kit with an option as to whether or not he certifies that the vehicle will comply with all applicable safety standards if completed according to his instrucitons. We would urge you to avoid undertaking the assembly of a kit that does not give assurance as to its ultimate ability to comply. If the producer of the kit takes the responsibility of certifying the completed vehicle, you as the asembler of the vehicle must exercise reasonable care in following the instructions he provides.; For your information I have enclosed a sheet entitled 'Where to Obtai Motor Vehicle Safety Standards and Regulations' which will direct you to the proper source for obtaining a copy of the safety standards and regulations.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam3155OpenMr. Bennie Stine, 1602 Emil Street, Madison, WI 53713; Mr. Bennie Stine 1602 Emil Street Madison WI 53713; Dear Mr. Stine: This responds to your letter asking whether you may remove th electronic antilock device from your vehicle. You state that the vehicle is unsafe with the antilock device in operation.; The National Highway Traffic Safety Administration believes that properly maintained antilock device can increase the safety of heavy duty vehicles. Accordingly, the agency encourages you to make sure that the antilock device on your vehicle is in the proper working order. However, if you want to remove the device, it is perfectly legal to do so. We suggest that you take the vehicle to its manufacturer or a representative of the manufacturer to be sure that the device is correctly removed and that the remaining braking system is properly adjusted.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam4690OpenMr. Diana L.D. Regan 43 Rockwood Drive Larchmont, NY 10538; Mr. Diana L.D. Regan 43 Rockwood Drive Larchmont NY 10538; "Dear Ms. Regan: This responds to your letter seeking an interpretatio of how our laws and regulations would apply to a product you have invented. Your product is designed to alter the alignment of the webbing of a lap/shoulder safety belt to improve the fit of the safety belt on children weighing between 40 and 85 pounds. According to your letter, the product is designed to be firmly attached to the webbing of both the lap belt portion and the shoulder belt portion of the safety belt. When the product is attached, it pulls down the shoulder belt portion of the safety belt so that it will pass across the child's chest and shoulder, instead of the neck. You asked whether this product would be considered a safety belt or a child restraint system for the purposes of our safety standards. The answer is that your product would not be considered to be either for the purposes of our standards, as explained below. Section S3 of Standard No. 209, Seat Belt Assemblies (49 CFR 571.209) defines a 'seat belt assembly' as 'any strap, webbing, or similar device designed to secure a person in a motor vehicle in order to mitigate the results of any accident, including all necessary buckles and other fasteners, and all hardware designed for installing such seat belt assembly in a motor vehicle.' (Emphasis added). Your device is not itself designed to secure a child in a motor vehicle. Instead, your device is designed to alter the alignment of the existing safety belt in the vehicle, so that the existing safety belt system in the vehicle can be adjusted to better fit a child occupant. Therefore, your device would not be a 'seat belt assembly' within the meaning of Standard No. 209. Section S4 of Standard No. 213 (49 CFR 571.213) defines a 'child restraint system' as 'any device except Type I or Type II seat belts, designed for use in a motor vehicle or aircraft to restrain, seat, or position children who weigh 50 pounds or less.' (Emphasis added). As explained above, your device is not a Type I or Type II seat belt. Additionally, for the reasons explained above, your device is not itself designed to restrain, seat, or position children. The restraining of the child would be accomplished entirely by the safety belt system already installed in the vehicle. Your device would simply alter the alignment of that safety belt system for the child. Therefore, your device would not be a 'child restraint system' within the meaning of Standard No. 213. You also asked for information regarding your responsibilities as the manufacturer and seller of this product. I have enclosed an information sheet we have prepared for new manufacturers of motor vehicle equipment. I have also enclosed copies of a February 11, 1988 letter to Mr. Roderick A. Boutin and a November 22, 1988 letter to Ms. Claire Haven. These two letters describe how products intended to enhance the comfort of safety belt wearers could be affected by our laws and regulations. The information sheet explains how to obtain copies of our laws and regulations. I hope this information is helpful. Sincerely, Stephen P. Wood Acting Chief Counsel Enclosures"; |
|
ID: aiam1168OpenMr. Bill Howard, Ratliff Motor Company, Post Office Box 400, Live Oak, FL 32060; Mr. Bill Howard Ratliff Motor Company Post Office Box 400 Live Oak FL 32060; Dear Mr. Howard: This is in response to your request for odometer disclosure forms. The Motor Vehicle Information and Cost Savings Act requires disclosur of odometer readings, but the regulations issued to implement the Act do not require you to use a federally printed form to make the disclosure, and the government therefore does not provide such forms. The regulation (Part 580) specifies an adequate format and is enclosed for your information. This format will satisfy federal disclosure requirements throughout the fifty states and permits use of identical forms in all jurisdictions.; The use of a commercially- prepared form is satisfactory if it contain the required information. The document does not have to be separate from other transfer documents, and in the case of a transferor using a bill of sale or other transfer document, the statement may be included within the form. The statement must be executed prior to the transfer. Either the original or a carbon copy may be given to the transferee.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam3505OpenDr. John R. Holsten, Director of Regulatory Affairs, M. Lowenstein Corporation, Technical Center, P.O. Box 2000, Lyman, SC 29365; Dr. John R. Holsten Director of Regulatory Affairs M. Lowenstein Corporation Technical Center P.O. Box 2000 Lyman SC 29365; Dear Dr. Holsten: This responds to your November 25, 1981, letter asking whethe children's car seats must comply with the flammability requirements of Standard No. 302, *Flammability of Interior Materials*. The answer to your question is yes. Section S5.7 of Standard No. 213, *Child Restraint Systems*, specifically states that each material used in a child restraint system shall comply with the flammability requirements of Standard NO. 302.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam1261OpenHonorable James R. Jones, House of Representatives, Washington, DC 20515; Honorable James R. Jones House of Representatives Washington DC 20515; Dear Mr. Jones: This is in reply to your letter of July 23, 1973, forwarding to u correspondence from Mr. G. N. Nichols, President, Midwestern Products, Incorporated, Tulsa, concerning the applicability of Federal regulations to an air suspension auxiliary axle manufactured by Midwestern Products. According to the manufacturer's advertising brochure, this axle, the 'Micro- Air Retractable Safety Axle,' is intended to be used on pick-up and bobtail trucks, particularly in the recreational vehicle and related fields.; There are presently no Federal motor vehicle safety standards o regulations that apply to the manufacture of these axles. However, persons who install them on *new* pick-up trucks or other vehicle types (a 'new vehicle under the National Traffic and Motor Vehicle Safety Act is one that has not yet been sold to a user) may be considered as vehicle alterers under provisions of NHTSA certification regulations which are to become effective February 1, 1974 (Docket No. 72-27, copy enclosed), and would be required to affix to the vehicle the label described in section 567.7 of those regulations.; Midwestern Products should be aware of these requirements whether i installs the Micro-Air axle or whether the installation is done by other parties. In the former case Midwestern would be responsible for affixing the required label, and in the latter it should provide the relevant information for the label regarding weight ratings to the party making the installation.; The NHTSA does not maintain a mailing list to provide copies of NHTS notices and regulations. Copies are available as indicated on the enclosed sheet, 'Where to Obtain Motor Vehicle sAfety Standards and Regulations.'; We are pleased to be of assistance. Sincerely, Robert L. Carter, Associate Administrator, Motor Vehicl Programs; |
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.