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
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ID: aiam0095OpenMr. Warren M. Heath, Commander, Engineering Section, Department of California Highway Patrol, P.O. Box 898, Sacramento, CA 95804; Mr. Warren M. Heath Commander Engineering Section Department of California Highway Patrol P.O. Box 898 Sacramento CA 95804; Dear Mr. Heath: Thank you for your letter of July 1, 1968, to Mr. George C. Nield concerning a clarification of paragraph S 3.4.3 of Federal Motor Vehicle Safety Standard No. 108.; Paragraph S 3.4.3 specifies that, as a minimum, the taillamps shall b illuminated when the headlamps are illuminated, except when the headlamps are being flashed. The phrase 'except when the headlamps are being flashed', permits the vehicle manufacturer to use a separate switch or flasher for illuminating the headlamps only when it would not be appropriate or in the interest of safety to simultaneously illuminate the taillamps and headlamps. In addition to the examples cited in your letter, such devices could also be used for flashing the headlamps on public transit vehicles to indicate an emergency situation.; Since the subject matter of S 3.4.3 is taillamps and since Federa Standard No. 108 is otherwise silent as to headlamp flashing, this matter appears to be within the purview of the California vehicle code.; Thank you for your continued interest in the motor vehicle safet standards.; Sincerely, David A. Fay, Office of Standards on Accident Avoidance Motor Vehicle Safety Performance Service; |
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ID: aiam0580OpenMr. Harold Visher, Vice President, Bandag Incorporated, 1055 Hershey Avenue, Muscatine, Iowa 52761; Mr. Harold Visher Vice President Bandag Incorporated 1055 Hershey Avenue Muscatine Iowa 52761; Dear Mr. Visher: #This is in reply to your letter of January 15, 1972 asking whether your 'treadless' passenger car tire will be considered a new tire under the Federal motor vehicle safety standard. You enclosed a diagram and explain that the 'treadless' tire is a 'brand new ... tire that we will furnish our dealers and then they will apply a new bandag tread to the tire and then sell the finished unit. #Based upon your description you have provided, we are of the opinion that you treadless tire is a new tire, and consequently subject to Motor Vehicle Safety Standard No. 109. Also, as each dealer applies the tread to the tire,each would be considered a 'manufacturer' under the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1381 *et seq.*), and be responsible for the requirements imposed upon manufacturers by the Act, and the standards and regulations issued pursuant to it. #We are pleased to be of assistance. #Yours truly, Richard B. Dyson, Assistant Chief Counsel; |
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ID: aiam5278OpenMr. J. Z. Peepas Selecto-Flash, Inc. P.O. Box 879 Orange, NJ 07051; Mr. J. Z. Peepas Selecto-Flash Inc. P.O. Box 879 Orange NJ 07051; "Dear Mr. Peepas: This is in reply to your FAX of November 12, 1993, t Taylor Vinson of this Office, the latest in a series of communications about how the conspicuity requirements of Standard No. 108 are to be applied to gooseneck trailers. On October 20, we sent you a correction of our earlier interpretation of S5.7.1.4.2(a). Our correction stated that the requirement is that conspicuity treatment not be obscured by trailer cargo. If conspicuity treatment is applied to the gooseneck of a container trailer, we understand that it will be obscured by the container (cargo) when it is in place. S5.7.1.4.2(a) also specifies that conspicuity treatment 'need not be continuous as long as not less than half of the length of the trailer is covered and the spaces are distributed as evenly as practicable.' The length of the gooseneck is included in determining the overall length of the trailer for purposes of calculating the half length that must be covered by the conspicuity treatment (which, of course, would be greater than half the length behind the gooseneck). You have suggested that we reevaluate the effect of excluding the gooseneck from compliance with the conspicuity requirements. There is nothing in Standard No. 108 that prohibits a manufacturer from applying retroreflective sheeting to the gooseneck. Indeed, some manufacturers may wish to do so to provide conspicuity of the entire trailer side when the trailer is traveling without its cargo. However, conspicuity treatment on a gooseneck is not counted in determining whether at least half the trailer side is covered. An example may clarify this for you. Let us say that the overall length of the trailer is 40 feet, including an 8-foot gooseneck. The amount of the side to be covered is not less than 20 feet. The area to be covered is the 32 feet between the rear bolster to the point immediately behind the gooseneck's terminus. Thus, regardless of whether conspicuity treatment is applied to the gooseneck, at least 20 feet of this 32-foot length must be covered in order to comply with Standard No. 108, and the spaces must be distributed as evenly as practicable. Standard No. 108 does not address the issue of the length of the spaces between strips, and a manufacturer may choose 4 feet or whatever is feasible for the trailer at hand. On the basis of this interpretation letter, we believe that Selecto-Flash ought to be able to judge whether the conspicuity treatments on Prints A-1, A-2, B-1 and B-2 accord with Standard No. 108. Sincerely, John Womack Acting Chief Counsel"; |
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ID: aiam4890OpenMr. Dwayne R. Szot 1404 Lay Boulevard Kalamazoo, MI 49001; Mr. Dwayne R. Szot 1404 Lay Boulevard Kalamazoo MI 49001; "FAX 616-382-0429 Dear Mr. Szot: This responds to your FAXed letter o June 28, l99l, with respect to your prospective importation from Poland of a 10-year old Syrena passenger car. We have also received a letter from Roy Slade, President, Cranbrook Academy of Art, relating to you. As you have explained, you intend to remove the engine upon arrival to meet EPA approval. You intend the remainder of the vehicle to become a 'time capsule' containing artifacts relating to the hopes and dreams of Poles, here and abroad, for the future, and their feelings about the past and present. You will transport the car among Polish communities here, and then seal the car in November in a Plexiglas box. For the next 25 years, the car will be displayed in its box at museums and art galleries, and, in 2016, will be returned to Poland. As you undoubtedly know, motor vehicles and motor vehicle equipment must comply with all applicable Federal motor vehicle safety standards in order to be imported into the United States, with such exceptions as Congress has authorized in the Imported Vehicle Safety Compliance Act of l988, and as have been set forth in the implementing regulation, 49 CFR Part 591. The Syrena, of course, does not meet these standards. The Act does not specifically permit the importation of a noncomplying vehicle for purposes of static display, though it does allow admission for purposes of 'research, investigations, studies, demonstrations or training, or competitive racing events.' We have not interpreted any of these provisions as allowing importation for display. The question then is whether the importation of the Syrena for the purposes described may nonetheless be justified because it presents no threat to motor vehicle safety. We note that you will satisfy the concerns of EPA by removal of the engine. This, in itself, does not result in the Syrena becoming something other than a motor vehicle, but it does mean that the Syrena cannot be driven on the public roads. Further, under the circumstances you describe, should the vehicle be towed, it is unlikely to be occupied by passengers because of the quantity of its contents. Under the circumstances you have described, the Syrena time capsule will present no threat to motor vehicle safety. Although the importation of this vehicle may be a technical violation of the l988 Act, it would not be the type of violation that this agency, in the exercise of its prosecutorial discretion, would pursue. You may therefore present this letter to the appropriate Customs officials at the port where the Syrena will arrive for entry into the United States as a statement from the Department of Transportation that it has no objection to your importation of the Syrena time capsule. If you have further questions, you may refer them to Taylor Vinson of this Office (202-366-5263) who spoke with your wife last week. Sincerely, Paul Jackson Rice Chief Counsel"; |
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ID: aiam2047OpenMr. Rex Henger, Bergman & Hicks, Republic National Bank Tower, Dallas, TX 75201; Mr. Rex Henger Bergman & Hicks Republic National Bank Tower Dallas TX 75201; Dear Mr. Henger: This is in response to your letter of September 3, 1975, in which yo inquire as to the existence of regulations concerning vehicle certification.; The National Highway Traffic Safety Administration has promulgate regulations requiring vehicle manufacturers to affix to each vehicle a label stating that the vehicle as completed complies with applicable Federal Motor Vehicle Safety Standards (49 CFR SS 567 and 568). There is no requirement that 'stress capacity' be included in the certification label. However, the label must state the vehicle's gross vehicle weight rating (49 CFR S 567.4(g)(3)) and gross axle weight rating (49 CFR SS 567.4(g)(4) and 571.3). The gross axle weight rating is the value set by the manufacturer as the load- carrying capacity of a single axle system on the vehicle. The statutory basis for these regulations is section 114 of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. S1403).; We hope this information will be of assistance. Sincerely, Richard B. Dyson, Assistant Chief Counsel |
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ID: aiam3292OpenMr. William G. Milby, Manager, Engineering Services Department, Blue Bird Body Company, P.O. Box 937, Fort Valley, GA 31030; Mr. William G. Milby Manager Engineering Services Department Blue Bird Body Company P.O. Box 937 Fort Valley GA 31030; Dear Mr. Milby:#This responds to your letter of January 16, 1980, i which you asked a number of questions pertaining to Federal Motor Vehicle Safety Standard No. 101-80, *Controls and Displays*. The answers to your questions are presented below and are numbered to correspond with the numbering of the questions in your letter.#1. Section 5.2.1 provides that where Table 1 of Standard 101-80 shows both a symbol and identifying words or abbreviations for a particular control, use of the symbol is mandatory and use of the words or abbreviations is optional.#2. When a manufacturer identifies a control with both the symbol shown in Table 1, Column 3, and the identifying words or abbreviations shown in Table 1, Column 2, only the symbol is subject to the illumination requirements of Section S5.3. That section states that with certain exceptions (i.e., foot operated controls or hand operated controls mounted upon the floor, floor console or steering column or in the windshield header area) 'the identification required by S5.2.1 or S5.2.2 of any control listed in column 1 of Table 1 and accompanied by the word 'yes' in the corresponding space in column 4 shall be capable of being illuminated whenever the headlights are actuated.' Since this section refers only to the identification required by Safety Standard 101-80, it does not apply to identification which is optional under the standard.#3., 4., 5., 6., 7., 8. In questions designated by these numbers, you asked whether the following controls are subject to the identification and illumination requirements of Standard 101-80:#>>>(a) a driver comfort fan which is not a part of the windshield or rear window defrosting and defogging system or the heating and air conditioning system,#(b) hot water flow valves for heaters which are opened in winter and then closed again in summer,#(c) heater fresh air control valves used to control the ratio of fresh to recirculated air entering the heater,#(d) driver's side window defroster control,#(e) driver's fresh air vent control,#(f) fan control for an optional driver's heater which directs air at the driver's feet.<<<#Section 5 of Standard 101-80 states that each vehicle that is subject to the standard and is manufactured with any control listed in Section 5.1 or in column 1 of Table 1 must comply with the requirements of Standard 101-80 regarding the location, identification and illumination of such control. Of the controls listed above, those lettered (a), (d) and (e) are not listed in either of these locations and thus are not subject to these requirements. Items (b), (c) and (f) are part of a heating or air conditioning system indicated in column 1 of Table 1 and is therefore subject to the location and identification requirements of Standard 101-80. However, the fan control, which directs air at the driver's feet, is not subject to the illumination requirements, since section 5.3.1 states, 'control identification for a heating and air conditioning system need not be illuminated if the system does not direct air directly upon windshield.' Likewise, if the hot water flow valves and fresh air control valves are 'mounted upon the floor, floor console or steering column, or in the windshield header area,' then section 5.3.1 does not require them to be illuminated.#9. In your question 9, you asked whether the penultimate line in Table 2 concerning malfunctions in antilocks applies only to vehicles equipped with air brakes and whether the last line concerning brake system malfunctions applies only to vehicles equipped with hydraulic brakes.#The penultimate line of Table 2 applies to all vehicles less than 10,000 pounds GVWR which are equipped with an antilock system, regardless of whether they are air or hydraulic brake equipped vehicles. The agency included the reference to Standard 105, *Hydraulic Brake Systems*, to indicate that section 5.3 of that standard permits a manufacturer to use either a yellow or red warning light depending on whether there is a separate indicator that only warns of antilock failure or there is an indicator which warns of antilock and other brake system failures.#The last line of Table 2 concerning the telltale for brake system malfunction applies to all vehicles equipped with this type of telltale regardless of the type of brake system. The agency included the reference to Standard 105 since section 5.3 of that standard specifies other requirements that brake system malfunction indicators used in hydraulic brake systems must meet.#10. This agency has never established specific size requirements for the identification symbols specified in Tables 1 and 2 of Standard 101-80. Sections 5.2.1 and 6 only require that such symbols be visible to a driver restrained by crash protection equipment.#11. None of the display requirements of Table II of Standard 101-80 apply to vehicles with a GVWR exceeding 10,000 pounds. Displays included in such vehicles in accordance with other standards are subject only to the provisions of those standards.#12. Section 5.3.1 provides that the illumination requirements of Standard 101-80 do not apply to hand operated controls mounted on the steering column. Accordingly, they are not applicable to a hazard control mounted on the steering column.#13. If the clearance lamps are controlled with the headlamp switch, Table 1, footnote 2, of the standard provides that the only identification required is the headlamp switch symbol.#14. Standard 101-80, section 5.2.1, states that controls must be identified with the symbol indicated in Table 1 and that such identification shall be placed on or adjacent to the control. The agency has previously indicated that manufacturers could use a symbol that is a minor deviation from the required symbol, as long as the symbol used substantially resembles that specified in the standard (43 FR 27541, June 26, 1978). Thus, if the wiper symbol you want to use is only a minor deviation and substantially resembles the required wiper symbol, you may use it.#15. You enclosed in your letter a blueprint showing a bank of switches which control multispeed fans and asked whether the identification shown in the print would comply with the requirements of Standard 101-80. Since the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1391) requires manufacturers to certify their compliance with all applicable Federal motor vehicle safety standards, this agency does not approve products. However, from our understanding of the information you have provided, it appears that the identification you propose to use for fan controls would comply with Standard 101-80. This opinion is based on the fact that your blueprint shows use of the fan symbol in accord with section 5.2.1 and identification of each function of the fan switch in accord with section 5.2.2.#16. With respect to air conditioning systems:#>>>(1) Section 5.3.1 does not require illumination of the control identification if the system does not direct air directly upon the windshield.#(2) Table 1 and section 5.2.1 require the fan symbol to be used to identify the fan for an air conditioning system,#(3) If the air conditioning system control regulates temperature over a quantitative range, the extreme positions must be identified in accord with 5.2.2.<<<#17. With respect to vehicles over 10,000 pounds GVWR, the requirements of Standard 101-80 concerning telltales used to indicate high engine coolant temperature or low engine oil pressure are inapplicable. With respect to vehicles less than 10,000 pounds GVWR, these requirements are applicable. In a letter to Ford Motor Company (copy enclosed), this agency stated that use of the engine symbol which Ford proposed for identification of such telltales would comply with the requirements of Standard 101-80.#Sincerely, Frank Berndt, Chief Counsel; |
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ID: aiam4557OpenMr. William Shapiro Volvo Cars of North America Rockleigh, NJ 07647; Mr. William Shapiro Volvo Cars of North America Rockleigh NJ 07647; "Dear Mr. Shapiro: This responds to your letter concerning the testin of hydraulic brake hose assemblies to the whip resistance requirement (S5.3.3) of Standard No. 106, Brake Hoses. I regret the delay in responding. Your question relates to Table II of Standard No. 106, which specifies the amount of slack that should be introduced when mounting brake hose assemblies on the whip test apparatus. (The amount of the hose indicated as 'slack' in Table II is the difference between the projected length of the hose assembly (when mounted in the whip test machine) and the free length of the hose while maintained in a straight position.) Slack must be present in the hose when mounted on the whip test machine to enable the proper 'whipping' movement of a brake hose assembly. Without slack, an assembly would probably be incapable of withstanding any rotation of the movable header of the whip test apparatus described in Standard No. 106 without rupturing. Table II specifies the amount of slack for some sizes of assemblies, and not for others. You ask whether a hydraulic brake hose assembly of a size falling in the latter category--viz., an assembly comprised of a brake hose that is 19 to 24 inches in free length, and which is more than one-eighth inch or three millimeters (mm.) in diameter--'need not be tested to meet or exceed the whip resistance requirement' of the standard. With regard to NHTSA's Standard No. 106 compliance testing, your understanding is correct that Table II does not specify the amount of slack for testing assemblies of the size you describe. Due to the absence of the slack specification, NHTSA does not require testing of such assemblies to the whip resistance requirements of the standard. With regard to your certification that the brake hose assemblies you manufacture comply with all applicable requirements of Standard No. 106, you are correct that hydraulic brake hose assemblies of the size you describe are not subject to the whip resistance requirements. However, the agency urges manufacturers to ensure that these assemblies perform in a safe manner while subject to environmental conditions of vehicle operations which may result in flexing of the brake hose or brake hose assembly. Please contact my office if you have further questions. Sincerely, Erika Z. Jones Chief Counsel"; |
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ID: aiam3338OpenMr. Emerson D. Gilbert, Yellowstone, Inc., 28163 C.R. 20 W., P.O. Box 1128, Elkhart, Indiana 46515; Mr. Emerson D. Gilbert Yellowstone Inc. 28163 C.R. 20 W. P.O. Box 1128 Elkhart Indiana 46515; Dear Mr. Gilbert: This is in response to your letter forwarding your firm's vehicl identification numbering system and requesting confirmation that it complies with Federal Motor Vehicle Safety Standard No. 115, *Vehicle Identification Number*.; The National Highway Traffic Safety Administration does not giv advance approval of a manufacturer's compliance with motor vehicle safety standards or regulations, as it is the manufacturer's responsibility under the National Traffic and Motor Vehicle Safety Act to ensure that its vehicles comply with the applicable safety standards. However, my office has reviewed your proposed system. Based on our understanding of the information which you have provided, your system apparently complies with Standard No. 115.; Sincerely, Frank Berndt, Chief Counsel |
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ID: aiam1305OpenMr. Kurt Meier, Porsche, Research and Development, 8124 Billow Vista Drive, Playa Del Rey, CA 90291; Mr. Kurt Meier Porsche Research and Development 8124 Billow Vista Drive Playa Del Rey CA 90291; Dear Mr. Meier: Thank you for your letter of September 2, 1973, to Mr. Jame Hofferberth of my staff, inquiring if a particular safety belt system which is illustrated in your enclosures meets the criteria for a passive restraint system.; The interpretation of a passive restraint system published in th Federal Register on May 4, 1971 (36 F.R. 8296) was:; >>>'The concept of an occupant protection system that requires 'n action by vehicle occupants' as used in Standard No. 208 is intended to designate a system that requires no action other than would be required if the protective system were not present in the vehicle.'<<<; With respect to your belt system, a requirement for placing the belt i the storage holder when leaving the car would be considered 'action' and not permitted under the above interpretation of a passive system. However, if the belt system could be entered and exited with essentially no action, in the event the storage holder was not used, automatically releasing 'convenience' holder would not compromise the belt's qualification as a passive system.; Sincerely, Robert L. Carter, Associate Administrator, Motor Vehicl Programs; |
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ID: aiam4107OpenMr. Wayne Ivie, Manager, Support Section, Oregon Department of Transportation, Motor Vehicles Division, 1905 Lana Avenue N.E., Salem, OR 97314; Mr. Wayne Ivie Manager Support Section Oregon Department of Transportation Motor Vehicles Division 1905 Lana Avenue N.E. Salem OR 97314; Dear Mr. Ivie: Thank you for your letter concerning Oregon's new vehicle code. Yo asked us to review the code and comment on possible Federal preemption of Oregon's laws for motor vehicle equipment. We apologize for the delay in responding to your inquiry.; On March 19, Ms. Hom of my staff explained in a telephone conversatio that this office is unable to undertake a general review of your state vehicle code as you requested. It would be more appropriate if your legal department reviewed your requirements.; Your letter also requested a clarification of our regulatory definitio of a 'bus.' You asked whether we have a definition of a 'bus' separate from definitions for 'school buses' or 'commercial motor buses.' You appeared to question whether privately-owned passenger vans would be classified as buses since Oregon currently considers 15-passenger vans as either 'passenger vehicles' or 'trucks.'; NHTSA's regulatory definitions for motor vehicles, issued for purpose of the Federal motor vehicle safety standards, are set forth at 49 CFR Part 571.3. We define a 'bus' as a motor vehicle, except a trailer, designed for carrying more than 10 persons. This definition would include 15-passenger vans, and would thus apply to both commercial motor coaches and privately-owned 15-passenger vans.; Our definition of a 'bus' is separate from our 'school bus' definition While the latter term incorporates our 'bus' definition, it includes further criteria based on the intended use of the vehicle. Under Part 571.3, a 'school bus' is a bus that is sold for purposes that include carrying students to and from school or related events (excluding common carriers in urban transportation). If a new 15-passenger van were sold for school transportation purposes, it would be considered a 'school bus' and would have to comply with NHTSA's school bus safety standards.; For purposes of understanding the interaction between Federal and stat vehicle definitions, it is important to distinguish NHTSA's motor vehicle safety standards from state safety standards. State motor vehicle safety regulations apply to the sale and use of motor vehicles. Oregon's vehicle definitions are relevant for determining state requirements applicable to the sale and use of particular classes of motor vehicles. On the other hand, our regulations apply to the manufacture and sale of new motor vehicles, and our definitions specify categories of vehicles subject to appropriate Federal motor vehicle safety standards. New vehicles included within particular categories must be certified as complying with the safety standards applying to that vehicle type. The applicability of our safety standards to a vehicle is not altered by the fact that a vehicle type is classified differently under state law. Thus, although Oregon classifies 15-passenger vans as passenger vehicles or trucks, manufacturers of new 15-passenger vans must manufacture those vehicles to Federal safety standards for buses, or school buses if intended for school use.; I hope this information is helpful. Please contact my office if yo have further questions.; 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.