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: aiam2405OpenMr. Sicks, Fachnormenausschuss Kraftfahrzeuge - FAKRA, D-6000 Frankfurt (Main) 17 - Westendstrasse 61, Postfach 1742 49; Mr. Sicks Fachnormenausschuss Kraftfahrzeuge - FAKRA D-6000 Frankfurt (Main) 17 - Westendstrasse 61 Postfach 1742 49; Dear Mr. Sicks: This is in response to your letter of March 31, 1975, in which yo recommend a modification of the testing procedures pursuant to Standard No. 302, *Flammability of Interior Materials*. Your modification would require the presence of support wires in all tests. After consideration of the recently-compiled test data on the use of support wires in the testing procedures, the NHTSA has decided that modification of the standard should be considered along the lines you suggest.; The NHTSA has interpreted Standard No. 302 to permit the use of suppor wires when any bending of the tested material occurred. At the time of that interpretation, it was believed that support wires would not influence the test results. More recent testing by the agency indicates that the use of support wires does significantly affect burn rates. For this reason, the agency is considering various possibilities in addition to the one you suggest.; Thank you for sending us a copy of your Draft International Standard We appreciate your concern in this matter.; Sincerely, Frank A. Berndt, Acting Chief Counsel |
|
ID: aiam0438OpenMr. G. Boschetti, Director, Automobiles, Peugeot, 75, Avenue de la Grande-Armee, Paris 16e, France; Mr. G. Boschetti Director Automobiles Peugeot 75 Avenue de la Grande-Armee Paris 16e France; Dear Mr. Boschetti: We appreciate the opportunity to further discuss the questions yo raised during our visit of June 9 and 10. I will try to answer each question as fully as possible.; 1. It would be unfortunate if the effect of our standards on domesti passenger car production in Europe is to raise costs to the point where significant numbers of people are forced to rely on cheaper and more dangerous vehicles such as motor driven cycles. However, we do not think this result likely in the light of the continuing demand for inexpensive passengers cars and in the absence of legislation by the European nations to compel adoption of the costlier safety features.; 2. We are aware of the concern of foreign manufacturers with th effects of the standards. The National Highway Traffic Safety Administration will attempt to be as flexible as possible, consistent with its mandate to insure the safety of vehicles sold in the United States. The discretion allowed the agency to exempt vehicles from a standard is a matter that Congress will have to decide. At the present time, the exemption authority given the National Highway Traffic Safety Administration by the 1966 Act has expired, and we are therefore unable to agree to any exemptions unless Congress chooses to recreate the exemption authority in some form.; 3. In the development of standards, the National Highway Traffic Safet Administration attempts to evaluate their effects on foreign as well as domestic manufacturers. As you are aware, it is sometimes not possible to reconcile all points of view on a standard, but we would urge you to make every effort to set forth your position on proposed rules during the comment period.; 4,5. Your comments on the proper height for bumpers and the problem o the license plate location have been considered in the context of the rulemaking on Standard No. 215. The amendment issued on June 22, 1971, should serve to lessen the height problem to some degree, and on the basis of present data we regard the height thereby established as reasonable for the overall vehicle population. The shape of the license plate itself is determined by the individual states and is not within our authority.; 6. The crash characteristics which you suggest for a vehicle's fron end seem reasonable, but because they fall beyond the scope of the present rulemaking on Standard No. 215, any consideration of them will have to be deferred. Although we realize that the front seats can supplement the side structure of a car in a side impact, the question as to whether the seats should be retained was considered in the development of the final version of Standard No. 214, and it was determined at that time that the standard would provide a more reliable measure of side strength if the tests were conducted with the seats removed. The National Highway Traffic Safety Administration is still of that opinion, although it would consider any additional information presented in support of a petition to amend the standard to allow retention of the seats.; 7. On the subject of prospective standards, the National Highwa Traffic Safety Administration is currently preparing a new version of the program plan for motor vehicle safety standards. The plan is intended to map the course of rulemaking for the next several years, and should serve to answer most of your questions on timing. We expect to announce the new plan in the very near future.; I hope this letter has been responsive to your questions. If not, or i additional questions arise, do not hesitate to ask us.; Sincerely, Douglas W. Toms, Administrator |
|
ID: aiam0592OpenMr. Berkley C. Sweet, Truck Body & Equipment Association, Inc., 5530 Wisconsin Avenue, Suite 1220, Washington, DC 20015; Mr. Berkley C. Sweet Truck Body & Equipment Association Inc. 5530 Wisconsin Avenue Suite 1220 Washington DC 20015; Dear Berkley: This is in response to the petition for rulemaking that you filed o behalf of manufacturers of ambulances and funeral coaches, requesting that they be given relief from some of the motor vehicle safety standards applicable to passenger cars, either by reclassification or otherwise.; You have pointed out the difficulties that ambulance and funeral coac manufacturers face in meeting the Exterior Protection standard, in light of the heavy weight of the vehicles and the necessary alterations of their rear ends for functional purposes. You noted that the Roof Crush Resistance standard will be difficult to meet because of the functional roof configuration of these vehicles, and that other passenger-car standards may cause similar problems in the future.; You also described the ways in which the chassis of these vehicles ar generally strengthened to bear their weight and perform their functions. The result of these alterations is such that these chassis, although they are produced by passenger car divisions of automobile manufacturers, are not passenger car chassis in the usual sense of the word.; A 'multipurpose passenger vehicle' is described in 49 CFR S 571.3 as ' motor vehicle with motive power, except a trailer, designed to carry 10 persons or less which is constructed either on a truck chassis or with special features for occasional off-road operation.' It has been determined that the policy considerations that led to the placing of vehicles with truck chassis into a category separate from passenger cars apply equally to ambulances and funeral coaches, and that the chassis used for these vehicles may reasonably be considered truck chassis for the purposes of this classification.; Please be advised, therefore, that the NHTSA will consider vehicle designed and manufactured for use as ambulances or funeral coaches to be multipurpose passenger vehicles, as defined in, and with respect to the application of, the motor vehicle safety standards and regulations.; Sincerely, Douglas W. Toms, Administrator |
|
ID: aiam4882OpenMr. Michael L. Harmon President Classic Interiors 30244-2 County Road 12 West Elkhart, IN 46514; Mr. Michael L. Harmon President Classic Interiors 30244-2 County Road 12 West Elkhart IN 46514; "Dear Mr. Harmon: This responds to your letter asking whether Standar No. 213, Child Restraint Systems, permits the installation of a built-in child restraint system (i.e., a child restraint system that is an integral part of the vehicle) in a multipurpose passenger vehicle (MPV), and if so, what requirements apply. As discussed below, a child restraint system built into an MPV would fall within the definition of 'child restraint system' in Standard No. 213 and would therefore have to comply with all the provisions of the standard that are generally applicable to child restraint systems. Since such a restraint would not be portable, it would not have to meet any requirement that is, by its own terms, or those of the compliance test procedure for that requirement, specifically applicable to 'add-on child restraint systems' only. Since it would be built into an MPV instead of a passenger car, it would not have to meet any requirement that is, for the same reasons, specifically applicable to 'built-in child restraint systems' only. The following sections of Standard No. 213 contain requirements that would apply to a child restraint built into an MPV: S5.2.1 (head support surface), S5.2.2 (torso impact protection), S5.2.4 (protrusion limitation), S5.4 (belts, buckles and webbing), and S5.7 (flammability). The principle requirements of the standard that would not apply are those in S5.l.l relating to dynamic performance. In view of the importance of the dynamic performance requirements for ensuring the safety of child restraint systems, we intend to begin rulemaking to apply those requirements to all built-in systems, not just to those installed in passenger cars. In the meantime, we suggest that manufacturers of such systems for MPVs carefully consider whether the systems provide protection comparable to that provided by built-in child restraint systems in passenger cars. You should also be aware that the National Traffic and Motor Vehicle Safety Act (l5 U.S.C. 1381-l431) imposes responsibilities on manufacturers of motor vehicles and motor vehicle equipment regarding safety-related defects. Manufacturers are responsible for ensuring that the vehicles and equipment they manufacture are free from safety-related defects and can perform their intended function safely. If the manufacturer or the agency determines that a safety-related defect (or noncompliance with an FMVSS) exists, the manufacturer is obligated under 151 et seq. of the Act to notify purchasers of its product and remedy the problem without charge. Manufacturers who fail to provide notification of or remedy for a defect or noncompliance may be subject to a civil penalty of up to $1,000 per violation. Legal Analysis Standard No. 2l3 applies to child restraint systems for use in motor vehicles and aircraft. See section S3. The term 'child restraint system' is defined 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.' See section S4. A child restraint system that is an integral part of an MPV would come within this definition. Some of Standard No. 2l3's requirements apply generally to 'child restraint systems,' i.e., without regard to whether a child restraint system is built-in or add-on or whether, if it is built-in, it is installed in a car or other type of vehicle. Since a child restraint system which is an integral part of an MPV comes within the definition of 'child restraint system,' it is required to meet all such requirements unless excepted. The following sections of Standard 213 contain requirements which apply generally to 'child restraint systems': S5.2.1 (head support surface), S5.2.2 (torso impact protection), S5.2.4 (protrusion limitation), S5.4 (belts, buckles and webbing), and S5.7 (flammability). In a number of instances, however, particularly with respect to dynamic performance, Standard No. 2l3 either specifies separate requirements for 'add-on child restraint systems' and 'built-in child restraint systems,' or provides a test procedure for these two types of child restraint systems only. The standard defines 'add-on child restraint system' without respect to the type of vehicle to which it might be added, i.e., as 'any portable child restraint system.' The term 'built-in child restraint system' is defined more restrictively, as 'any child restraint system which is an integral part of a passenger car.' (Emphasis added.) A child restraint system which is an integral part of an MPV does not come within either of these definitions, since such a restraint is neither portable nor a part of a passenger car. Therefore, Standard No. 2l3's requirements for 'add-on child restraint systems' and 'built-in child restraint systems,' do not apply to a child restraint system which is an integral part of an MPV. Similarly, those requirements for which the standard specifies a test procedure for 'add-on child restraint systems' and 'built-in child restraint systems' only do not apply to a child restraint system which is an integral part of an MPV. I hope this information is helpful. Please contact us if you have further questions. Sincerely, Paul Jackson Rice Chief Counsel"; |
|
ID: aiam2055OpenMr. John. H. Mueller, The Weatherhead Company, 300 East 131st Street, Cleveland, Ohio 44108; Mr. John. H. Mueller The Weatherhead Company 300 East 131st Street Cleveland Ohio 44108; Dear Mr. Mueller: #This is in response to your letter of July 9, 1975 concerning the banding requirements of Standard No. 106-74. You asked whether the requirements for a band may be avoided in the situation where a hose manufacturer makes a hose assembly to a vehicle manufacturer's 'specified requirements,' under the exception for hoses 'assembled and installed by a vehicle manufacturer.' #The exception in the standard for assemblies made by a vehicle manufacturer cannot be interpreted to apply to those made by a hose manufacturer, as you suggested, so the answer to your question must be no. It is the intent of the standard to distinguish between the two situations you described. #We are presently reviewing the labeling requirements of the brake hose standard in light of your letter and other information. If you wish to present further data and other arguments toward the revocation of the banding requirement, the appropriate form in which to do so would be a petition for rulemaking under Pard 552. #Your truly, Richard B. Dyson, Assistant Chief Counsel; |
|
ID: aiam0068OpenMr. William Lagerquist,Vice President,Minnesota Automotive, Inc.,502 Patterson Avenue,.Mankato,Minnesota 56001; Mr. William Lagerquist Vice President Minnesota Automotive Inc. 502 Patterson Avenue .Mankato Minnesota 56001; Dear Mr. Lagerquist:#Thank you for your letter of April 1, 1968, to th Motor Vehicle Safety Performance Service, concerning compliance with the Federal Motor Vehicle Safety Standard No. 105.#Basically, when a car dealer modifies a conforming vehicle, he then assumes responsibility for the vehicle s compliance to all applicable standards if that vehicle is distributed to a purchaser for purposes other than resale. Specifically, if a car dealer installs the Model 7900 Driver Training Brake on a conforming vehicle that he sells, than compliance to the Federal Motor Vehicle Safety Standard No. 105, as well as other applicable standards, is required. in the case where the dealer owns and loans the vehicle with the installed Model 7900, we would hope that he would again comply.#The enclosed ,literature may be of additional assistance to you in response to your inquiry.#Sincerely,Joseph R. O Groman,Acting Director,Office of Performance Analysis,Motor Vehicle Safety Performance Service; |
|
ID: aiam5285OpenThomas D. Price, President Strait-Stop ABAS Marketing, Inc. P.O. Box 5644 Norman, OK 73070; Thomas D. Price President Strait-Stop ABAS Marketing Inc. P.O. Box 5644 Norman OK 73070; "Dear Mr. Price: This responds to your letter concerning this agency' notice of proposed rulemaking (NPRM) to require medium and heavy vehicles to be equipped with an antilock braking system (58 FR 50739, September 28, 1993). You noted that the proposed definition for 'antilock brake system' incorporates the terminology 'rate of angular wheel rotation,' and requested a definition of this terminology. You also suggested that there is ambiguity as to the precise meaning of the word 'performance,' apparently with respect to the way that word is used in the preamble. Accordingly, you requested a definition of that word as well. By way of background information, the purpose of publishing NPRM's is to provide all interested persons an opportunity to comment on regulations being considered by the agency. If an interested person believes that the proposed regulatory text and/or the agency's explanation in a preamble concerning a proposed regulation are unclear, the appropriate place to make that argument is in a comment on the NPRM. If a person believes that a portion of the proposed regulation should be clarified in a particular manner, that recommendation also should be included in a comment. Similarly, if a person believes the agency's explanation for the proposed rule is unclear, the person can identify in comments the portion of the explanation at issue and explain the implications his or her concern has on the agency's decision concerning a possible final rule. Since the questions and views in your letter are in the nature of comments on the pending NPRM, we are placing a copy of your letter in the public docket for that NPRM. I want to assure you that your comments will be considered at the same time all the other public comments are considered. Only after considering the comments will NHTSA reach a decision on whether to issue a final rule. NHTSA does not issue separate letters or documents responding to individual public comments in a rulemaking. Instead, after carefully considering all comments, NHTSA provides its responses in the next relevant rulemaking notice, e.g., a final rule or a notice terminating the rulemaking. While we cannot provide specific responses to your questions, we note that pages 50742 and 50743 of the NPRM provide an extensive discussion about how the agency derived its definition for antilock braking system. This discussion explains that the definitions were derived in large part from the Society of Automotive Engineers (SAE) Recommended Practice J656, 'Automotive Brake Definitions and Nomenclature' (1988), and the Economic Commission for Europe's Regulation 13 (1988). We have enclosed for your information a copy of that SAE Recommended Practice, which uses the terminology 'rate of angular rotation of the wheel(s).' With respect to your question about the meaning of 'performance,' we note generally that each of this agency's safety standards specifies those requirements that are deemed necessary to obtain the desired safety performance from a particular vehicle system or item of equipment. Any design that will satisfy the requirements may be used for the system or item of equipment. I hope this information is helpful. Sincerely, John Womack Acting Chief Counsel Enclosure"; |
|
ID: aiam2540OpenMr. Robert N. Townsend, Townsend & Townsend Attorneys at Law, P. O. Box 366, 111 W. Second Street, Parsons, TN 38363; Mr. Robert N. Townsend Townsend & Townsend Attorneys at Law P. O. Box 366 111 W. Second Street Parsons TN 38363; Dear Mr. Townsend: This responds to your February 9, 1977, letter in which you ask how th National Highway Traffic Safety Administration determines whether a school bus must comply with the new school bus safety standards.; On April 1, 1977, several new standards will become effective relatin to the construction of school buses: Standard No. 220, *School Bus Rollover Protection*, Standard No. 221, *School Bus Body Joint Strength*, and Standard No. 222, *School Bus Passenger Seating and Crash Protection*. Further, several old standards have been amended to provide special requirements for school buses. These amendments also become effective on April 1.; Section 108(a)(1)(A) of the National Traffic and Motor Vehicle Safet Act (Pub. L. 89-563), as amended (Pub. L. 93-492), prohibits the manufacture for sale, sale, offer for sale, or introduction or delivery for introduction into interstate commerce of any motor vehicle or item of motor vehicle equipment manufactured on or after the date any applicable Federal motor vehicle safety standard takes effect that does not conform to the standard. This means that any school bus manufactured on or after April 1, 1977, must comply with the school bus safety standards, regardless of the date on which the bus is actually sold or introduced into interstate commerce.; For vehicles that you complete by mounting a body on a new chassis, yo are permitted to choose as the date of manufacture either the date of manufacture of the incomplete vehicle (as defined in Part 568, *Vehicles Manufactured in Two or More Stages)*, the date of final completion of the vehicle, or a date between those two dates. Only those standards in effect on the date chosen to represent the date of manufacture would be applicable to the vehicle, irrespective of the date upon which the vehicle is sold to the ultimate consumer.; I am enclosing copies of the new school bus safety standards and Par 568 for your information.; Sincerely, Frank Berndt, Acting Chief Counsel |
|
ID: aiam0087OpenMr. Philips B. Boyer, 2911 West 12th Street, Little Rock, AR 72204; Mr. Philips B. Boyer 2911 West 12th Street Little Rock AR 72204; Dear Mr. Boyer: This is in response to your letter of June 24 to the Department o Transportation asking if manufacturers of motor homes are 'required to equip the seats in such units with seat belts.'; The self- propelled motor home is classified as a 'multipurpos passenger vehicle' for purpose of the Federal motor vehicle safety standards. Currently seat belt installations and seat belt assembly anchorages are not required for multipurpose passenger vehicles, but if a seat belt assembly is provided by the vehicle manufacturer it must meet the requirements of Federal standard No. 209.; On October 14, 1967 the Federal Highway Administrator establishe dockets to receive comments on possible requirements for seat belt installations and seat belt assembly anchorages in multipurpose passenger vehicles. These comments are now under evaluation.; Sincerely, Robert M. O'Mahoney, Assistant Chief Counsel |
|
ID: aiam2110OpenMr. Brian Gill, Assistant Manager, Safety & Environmental Activities, American Honda Motor Co., Inc., P.O. Box 50 - 100 W. Alondra Blvd., Gardena, CA 90247; Mr. Brian Gill Assistant Manager Safety & Environmental Activities American Honda Motor Co. Inc. P.O. Box 50 - 100 W. Alondra Blvd. Gardena CA 90247; Dear Mr. Gill: This is in response to your letter of October 14, 1975, in which yo request an interpretation of Standard No. 301 as it applies to a vehicle with an electric fuel pump that operates only when the ignition switch is in the 'ON' position and the engine oil pressure is within the normal operating range.; You indicate in you letter that, in effect, the fuel pump can onl operate when the vehicle's engine is running. Paragraph S7.1.3 of Standard No. 301 requires that an electrically driven fuel pump be operating at the time of the crash tests if the pump 'normally runs when the vehicle's electrical system is activated.' It appears from your letter that activation of the electrical system by switching the ignition to 'ON' will not by itself activate the fuel pump. As a result, the pump need not be operating at the time of the crash tests.; Sincerely, Frank A Berndt, Acting 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.