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NHTSA Interpretation File Search

Overview

NHTSA's Chief Counsel interprets the statutes that the agency administers and the standards and regulations that it issues. Members of the public may submit requests for interpretation, and the Chief Counsel will respond with a letter of interpretation. These interpretation letters look at the particular facts presented in the question and explain the agency’s opinion on how the law applies given those facts. These letters of interpretation are guidance documents. They do not have the force and effect of law and are not meant to bind the public in any way. They are intended only to provide information to the public regarding existing requirements under the law or agency policies. 

Understanding NHTSA’s Online Interpretation Files

NHTSA makes its letters of interpretation available to the public on this webpage. 

An interpretation letter represents the opinion of the Chief Counsel based on the facts of individual cases at the time the letter was written. While these letters may be helpful in determining how the agency might answer a question that another person has if that question is similar to a previously considered question, do not assume that a prior interpretation will necessarily apply to your situation.

  • Your facts may be sufficiently different from those presented in prior interpretations, such that the agency's answer to you might be different from the answer in the prior interpretation letter;
  • Your situation may be completely new to the agency and not addressed in an existing interpretation letter;
  • The agency's safety standards or regulations may have changed since the prior interpretation letter was written so that the agency's prior interpretation no longer applies; or
  • Some combination of the above, or other, factors.

Searching NHTSA’s Online Interpretation Files

Before beginning a search, it’s important to understand how this online search works. Below we provide some examples of searches you can run. In some cases, the search results may include words similar to what you searched because it utilizes a fuzzy search algorithm.

Single word search

 Example: car
 Result: Any document containing that word.

Multiple word search

 Example: car seat requirements
 Result: Any document containing any of these words.

Connector word search

 Example: car AND seat AND requirements
 Result: Any document containing all of these words.

 Note: Search operators such as AND or OR must be in all capital letters.

Phrase in double quotes

 Example: "headlamp function"
 Result: Any document with that phrase.

Conjunctive search

Example: functionally AND minima
Result: Any document with both of those words.

Wildcard

Example: headl*
Result: Any document with a word beginning with those letters (e.g., headlamp, headlight, headlamps).

Example: no*compl*
Result: Any document beginning with the letters “no” followed by the letters “compl” (e.g., noncompliance, non-complying).

Not

Example: headlamp NOT crash
Result: Any document containing the word “headlamp” and not the word “crash.”

Complex searches

You can combine search operators to write more targeted searches.

Note: The database does not currently support phrase searches with wildcards (e.g., “make* inoperative”). 

Example: Headl* AND (supplement* OR auxiliary OR impair*)
Result: Any document containing words that are variants of “headlamp” (headlamp, headlights, etc.) and also containing a variant of “supplement” (supplement, supplemental, etc.) or “impair” (impair, impairment, etc.) or the word “auxiliary.”

Search Tool

NHTSA's Interpretation Files Search



Displaying 4871 - 4880 of 16514
Interpretations Date
 search results table

ID: aiam3891

Open
Ms. Phyllis A. Sirine, Administrative Secretary, St. Peter's School, 319 Lombard Street, Philadelphia, PA 19147; Ms. Phyllis A. Sirine
Administrative Secretary
St. Peter's School
319 Lombard Street
Philadelphia
PA 19147;

Dear Ms. Sirine: This responds to your letter to me concerning your use of 13 and 1 passenger vans to transport students to and from extracurricular activities. In a telephone call on January 30, 1985, Mr. John Womack explained how our school bus regulations affect your school's choice of buses. This letter follows up on that conversation and confirms Mr. Womack's discussion of our regulations.; As I understand it, Pennsylvania has recently amended its law to defin 'bus' to mean 'a motor vehicle designed for carrying more than ten persons, including the driver.' The old definition had excluded the driver. In effect, a van designed to carry more than ten persons is now a 'bus' under Pennsylvania law. To transport students in a van of that size, a school would need to conform the van to the State's requirements for school buses.; The recent change in Pennsylvania law does not in any way affect ho our regulations apply to your 13 and 15 passenger vans. Your vehicles have always been classified as buses under Federal law, since under our regulations a bus is defined as a motor vehicle designed for carrying more than ten persons. Further, your vehicles are 'school buses' as that term is defined in the Vehicle Safety Act. The basic test under the Vehicle Safety Act is whether, as determined at the time of its first sale, a bus would be used to transport school children to or from school or related events. It is not relevant that the school uses the vehicles only occasionally. When the buses were sold to your school, it should have been clear to the dealer or manufacturer that the vehicles would be used as school buses.; It appears that St. Peter's purchase of new vans for the transportatio of students raises questions of compliance with Federal law by the dealers who sold you the vans. The Vehicle Safety Act required the dealer or manufacturer to sell vehicles which were certified as meeting all applicable motor vehicle safety standards. With respect to your future purchases of new vehicles, I urge you to keep in mind that the dealers are obligated to sell you vehicles that meet the school bus safety standards. They should know that they are at risk if they sell nonconforming vehicles.; The Vehicle Safety Act does not prohibit you from operating the 13 an 15 passenger vans. There might, however, be impediments under Pennsylvania State law. We administer a set of guidelines for state highway safety programs under the authority of the Highway Safety Act (Public Law 89-564). These guidelines, called Highway Safety Program Standards, cover a wide range of subjects, including school buses. Individual states have chosen to adopt some or all of the guidelines as their own policies governing their highway safety programs. Highway Safety Program Standard No. 17 (HSPS 17), specifies that a bus used to transport 16 or less students must either be identified with the words 'School Bus' and comply with the standard's requirements for color, mirrors and signal lamps, or be devoid of all of these characteristics. As it happens, however, a bus sold for use as a school bus is required by the Vehicle Safety Act to have warning lights and mirrors (as well as many other safety features). Because it must have this equipment, a 13 or 15 passenger bus in a State whose law fully incorporates HSPS 17 would have to be painted and signed as a school bus. For a state that has adopted this standard as its own policy, these specifications apply to activity buses as well as to the buses used for daily transportation.; I want to stress that HSPS 17 will affect you only if Pennsylvania ha adopted it and if Pennsylvania accepts our view that the specifications apply to activity buses. Your State officials will be able to give you more information about other State requirements for school buses.; Please let me know if you have any further questions. Sincerely, Frank Berndt, Chief Counsel

ID: aiam5046

Open
Richard Allison Program Manager The Bott Group, Inc. 32330 Howard Avenue Michigan Heights, MI 48071; Richard Allison Program Manager The Bott Group
Inc. 32330 Howard Avenue Michigan Heights
MI 48071;

"Dear Mr. Allison: This responds to your letter of August 20, 199 requesting an interpretation of Standard No. 216, Roof Crush Resistance. Specifically, you requested 'an interpretation of 1) the proper application and orientation of the test device (S6.2 of this standard) and 2) the distance the test device is allowed to travel (paragraph S4 of this standard), when testing vehicles equipped with roof mounted accessories, such as roof racks (luggage racks).' You believe that there are three possible test conditions. The first condition would conduct the test either without the roof rack installed or with the roof rack removed, and with the test device positioned in accordance with S6.2. The second condition would conduct the test with the roof rack installed, and with the test device positioned using the point of contact established under test condition 1. The third condition would conduct the test with the roof rack installed, and with the test device positioned in accordance with S6.2 to the roof rack. You requested our interpretation as to which is the correct test condition. In addition, you asked if we determined that either test condition 2 or 3 was correct, could the amount of distance traveled before contact with the roof be added to the allowable distance of test device travel under S4. We would conduct our compliance testing for Standard No. 216 with roof mounted accessories such as roof racks removed (your test condition 1). We would do so because the purpose of the test is to measure the strength of the roof, not the strength of roof mounted accessories. Further, as you have noted, conducting the test with roof mounted accessories in place could influence the positioning of the test device. I hope you find this information helpful. If you have any other questions, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992. Sincerely, Paul Jackson Rice Chief Counsel";

ID: aiam2783

Open
Mr. Stan Haransky, Truck Body and Equipment Association, Inc., 5530 Wisconsin Avenue, Suite 1220, Washington, DC 20015; Mr. Stan Haransky
Truck Body and Equipment Association
Inc.
5530 Wisconsin Avenue
Suite 1220
Washington
DC 20015;

Dear Mr. Haransky: This responds to your February 21, 1978, letter asking whether sectio 567.5(c)(7) of Part 567, *Certification*, requires a manufacturer to use all of the described statements on its certification label.; The answer to your question is no. That section provides that th listed certification statements are to be used as appropriate. Therefore, it is anticipated that a manufacturer will select for inclusion on its certification labels only those certification statements in subparagraph (c)(7) that are appropriate for the certification of its vehicles.; Sincerely, Joseph J. Levin, Jr., Chief Counsel

ID: aiam1906

Open
Benjamin Sachs, M.D., Associate Director, Division of Local Health Services, Room 360, Massachusetts Department of Public Health, 600 Washington Street, Boston, MA 02111; Benjamin Sachs
M.D.
Associate Director
Division of Local Health Services
Room 360
Massachusetts Department of Public Health
600 Washington Street
Boston
MA 02111;

Dear Dr. Sachs: In response to your request of April 4, 1975, I am enclosing a copy o Federal Motor Vehicle Safety Standard No. 208, several *Federal Register* notices which have modified the basic standard, and the Motor Vehicle and Schoolbus Safety Amendments of 1974. Also enclosed is a circular explaining how all the safety standards and regulations of the National Highway Traffic Safety Administration (NHTSA) may be obtained.; Until October 29, 1974, section S4.1.2 of the standard required a ignition interlock on 1974- and 1975-model passenger cars. As noted in the enclosed amendment (Docket 74-39, Notice 1), recent legislation mandated the deletion of this requirement, which was accomplished by NHTSA on October 29, 1974.; Manufacturers may now meet Standard No. 208 by providing (1) lap an shoulder belts at front outboard positions and lap belts at other positions, and (2) a continuous or flashing reminder light that operates only during the 4- to 8-second period after the ignition is operated and a continuous or intermittent audible warning signal which operates only during the 4- to 8-second period after the ignition is operated if the driver's lap belt is not in use. They may also provide certain types of 'passive restraint' devices in place of the seat belt assemblies.; Although the seat-belt interlock system is not prohibited, it is n longer a means of complying with the standard.; Yours truly, Richard B. Dyson, Assistant Chief Counsel

ID: aiam0614

Open
Mr. George A. Maty, Vice President and Sales Manager, Lindburg Cadillac, 2350 Market Street, St. Louis, MO 63103; Mr. George A. Maty
Vice President and Sales Manager
Lindburg Cadillac
2350 Market Street
St. Louis
MO 63103;

Dear Mr. Maty: Thank you for your letter of February 16, 1972, to Secretary Joh Volpe, concerning the length of seat belts in a 1972 Cadillac automobile.; Federal Motor Vehicle Safety Standard No. 208 Occupant Cras Protection, copy enclosed, specifies requirements for occupant restraint systems. Effective January 1, 1972, car manufacturers are required to provide Type 2 belt assemblies (lap-shoulder belts) at the front outboard seating positions and lap belts at other positions. The Type 2 belt assemblies may have either integral or detachable shoulder belts, but the distance between the intersection of the lap- shoulder belt and the vertical centerline of a 50th-percentile adult male occupant must be at least six inches when the seat is in its rearmost position. The purpose of this requirement is to reduce the possibility of the shoulder belt pulling the lap belt up onto the occupant's abdomen where it could cause serious injury in a crash.; We have examined several 1972 model cars and have found that som manufacturers have chosen belt designs that provide distances of ten inches or more between the lap-shoulder belt intersection and the centerline of the occupant. The standard does not prohibit distances greater than six inches, but it is obvious that the greater this distance, the closer the inboard end of the belt is to the seat and the more difficult it is to buckle the belt. I am happy to inform you that we have already initiated rule making action to amend Standard No. 208 that would prohibit such excessive distances.; Under the requirements of the National Motor Vehicle and Traffic Safet Act, copy enclosed, it is a violation of the law to sell a vehicle that does not conform to an applicable standard. Although the Act does not prevent the purchaser of a vehicle from altering or removing a safety device, after he has completed the purchase, we strongly advise him against such action. A dealer who performs such services after he has sold the vehicle does not violate the law, but he does his customer a disservice.; In regard to the belts in the Cadillac you sold to Mr. and Mrs. T Albert McCulley, we do not have the authority to grant or deny you permission to lengthen the inboard end of the belt. We can only suggest that perhaps you could lengthen the belt only to the extent that is necessary to provide a distance of not less than six inches between the intersection of the lap-shoulder belt and the centerline of a 50th-percentile adult male occupant measured in accordance with paragraph S7.1.2 of Standard No. 208.; Thank you for your interest in motor vehicle safety. If we can be o further assistance, please do not hesitate to contact us.; Sincerely, Robert L. Carter, Acting Associate Administrator, Moto Vehicle Programs;

ID: aiam2629

Open
Honorable Dixy Lee Ray, Governor of Washington, Olympia, WA 98501; Honorable Dixy Lee Ray
Governor of Washington
Olympia
WA 98501;

Dear Governor Ray: The purpose of this letter is to express this agency's views o legislation recently enacted by the State of Washington, which appears to be preempted by Federal regulation of the same subject matter.; Specifically we understand that R.C.W. S45.37.320 was amended in Ma 1977 to require that motor vehicle 'lighting devices'; >>>'...shall correlate with, and, so far as practicable, conform to th then current standards and specifications of the society of automotive engineers applicable to such equipment and to the headlamp standards established by the United Nations agreement concerning the adoption of approval and reciprocal recognition of approval for motor vehicle equipment and parts done at Geneva on March 20, 1958, as amended and adopted by the Canadian standards association (CSA standard D106.2): *Provided*, that the sale, installation, and use of any headlamp meeting the standards of either the society of automotive engineers or the United Nations agreement, as amended, shall be lawful in this state.'<<<; Under 15 U.S.C. 1392(d): >>>'Whenever a Federal motor vehicle safety standard established unde this title is in effect, *no State* or political subdivision of a State *shall have any authority* either *to establish*, or to continue in effect with respect to any motor vehicle or item of motor vehicle equipment *any safety standard applicable to the same aspect of performance of such vehicle or item of equipment which is not identical to the Federal standard.' [Emphasis added.]<<<; Pursuant to 15 U.S.C. 1392(a) [Section 103(a) of the National Traffi and Motor Vehicle Safety Act of 1966] Federal Motor Vehicle Safety Standard No. 108, *Lamps, Reflective Devices, and Associated Equipment* (49 CFR 571.108), has been established, effective January 1, 1972, as the Federal standard for lighting devices both as original and replacement equipment on motor vehicles.; Although Standard No. 108 incorporates by reference many lightin standards of the society of Automotive Engineers (SAE) it contains numerous qualifications of, and variations from, the SAE specifications. Even when Federal requirements and SAE specifications are identical, amendments by the SAE, which occur frequently, do not amend the corresponding Federal requirements. In short, that portion of the amendment to RCW S46.37.320 requiring compliance to SAE specifications does not establish requirements that are identical to those of Standard No. 108 and, in our opinion, are preempted by 15 U.S.C. 1392(d) and of no legal effect.; In addition, the United Nations Agreement, as amended by the Canadia Standards Association, permits the use of motor vehicle headlamps that are not of sealed beam construction and whose candlepower output may exceed 75,000. Further, it does not require that the headlamps be mechanically aimable. Standard No. 108, on the other hand, requires that headlamps on passenger vehicles be of sealed beam construction, imposes a limit of 75,000 candlepower on all but one type of headlamp, and specifies that all headlamps be mechanically aimable. Thus, the United Nations Agreement, as amended by the Canadian Standards Association, does not specify requirements for headlamps that are identical to those of Standard No. 108. This means that this part of the amendment to R.C.W. S46.37.320 is, in our opinion, also preempted by 15 U.S.C. 1392(d), and of no legal effect.; As a consequence, it is our conclusion that any person in Washingto manufacturing for sale, selling, offering for sale, introducing or delivering for introduction in interstate commerce, or importing in the United States through the State of Washington any lighting equipment that does not conform to Standard No. 108, in reliance upon R.C.W. S46.37.320, could be subject to civil penalties for apparent violations of 15 U.S.C. 1397(a) (1) (A) in an amount up to $800,000 (15 1399(a)). There is no preemption, however, of your State's right to specify requirements for lighting equipment not currently included in Standard No. 108 (*e.g.* foglamps).; Section 1392(d) and the Act's preemptive effect have been invariabl upheld. (See *e.g. Chrysler Corp. v. Malloy,* 294 F. Supp. 524 (U.S.D>C. Vt. 1968), *Chrysler Corp. v. Tofany*, 419 F.2d 499 (C.C.A. 2 1969)). We would also observe that the interpretation by an administering agency of its own statutes and regulations, has been viewed by courts as 'of controlling weight.' (*Thorpe v. Housing Authority of Durham* 393 U.S. 268 (1969) quoted with approval in *Chrysler Corp. v. Tofany, supra*, at 512.); We would appreciate the view of the State of Washington on thi subject. Questions on it may be referred to the Chief Counsel of this agency, Joseph J. Levin, Jr.; Sincerely, Joan Claybrook

ID: aiam5416

Open
Mr. Rick Rogers 9624 Davis Road Tampa, FL 33637-5004; Mr. Rick Rogers 9624 Davis Road Tampa
FL 33637-5004;

Dear Mr. Davis: Robert Hellmuth of this agency has sent us for repl your letter of June 8, 1994, commenting that 'a car's brake lights should go on not only when the brake pedal is pressed, but should also go on when the gas pedal is released.' The enclosed copy of a letter dated January 25, 1990, to Larry Snowhite, Esq., represents the agency's views on this matter, now as then. We appreciate the concern for safety that prompted you to get in touch with us. Sincerely, John Womack Acting Chief Counsel Enclosure;

ID: aiam3468

Open
Mr. Don W. Upson, Colt Industries, Inc., 1901 'L' Street, N.W., Suite 303, Washington, DC 20036; Mr. Don W. Upson
Colt Industries
Inc.
1901 'L' Street
N.W.
Suite 303
Washington
DC 20036;

Dear Mr. Upson: This responds to your recent letter asking whether any Federa regulations apply to propane fuel systems designed for use in motor vehicles.; I am enclosing an information sheet which sets forth the implication under Federal law of converting gasoline-powered vehicles to use propane or other gas, as well as a general discussion of auxiliary fuel tanks. From that discussion, you will see that there are no safety standards directly applicable to propane fuel tanks as pieces of automobile equipment. There are, however, specifications under the Bureau of Motor Carrier Safety regulations relating to propane fuel systems on commercial vehicles or to tanks used for shipment of propane gas in interstate commerce. If your tanks will be used on other than private vehicles, these regulations may be of interest to you. For further information, you may contact Mr. W. R. Fiste of the Bureau of Motor Carrier Safety (202-426-0033).; Sincerely, Frank Berndt, Chief Counsel

ID: aiam1455

Open
Mr. H. Tsukano, Submanager,Technical Divisions,Meiji Rubber & Chemical Co., Ltd.,Kojima-Building, 10-2, Nishishinjuku,1-Chome, Shinjuku-Ku, Tokyo, Japan; Mr. H. Tsukano
Submanager
Technical Divisions
Meiji Rubber & Chemical Co.
Ltd.
Kojima-Building
10-2
Nishishinjuku
1-Chome
Shinjuku-Ku
Tokyo
Japan;

Dear Mr. Tsukano:#This is in response to your February 27, 1974 request concerning brake hose identifications codes and labeling, conflicts of Federal and State standards,and procedures for certifying hose, end fittings, and hose assemblies in compliance with Standard No. 106, *Brake hoses*. This also responds to your March 25, 1974, (ref T-76) request for approval of your proposed hydraulic and vacuum brake hose labeling.#Notice 10 was published on February 26, 1974. It modified the labeling requirements,and a copy is enclosed. It is certain that another notice will be published shortly which may modify the marking requirements further. Therefore I advise that you not undertake modifications of your labeling in the near future.#In answer to your February 21 letter, if we require a code at a later date, the code will not relate to the MRA code. Concerning the marking of multi-piece fittings, the designation must appear on each part of a reusable end fitting, although this requirement is presently under reconsideration.#With regard to conflicting State regulations such as Pennsylvania's, our regulation as of September 1, 1974, preempts any State brake hose regulations which are not identical with respect to the same aspects of performance. The National Traffic and Motor Vehicle Safety Act of 1966 provides at S 103(d):#>>>Whenever a Federal motor vehicle safety standard established under this subchapter is in effect, no state or political subdivision of a State shall have any authority either to establish, or to continue in effect, with respect to any motor vehicle or item of motor vehicle equipment any safety standard applicable to the same aspect of performance of such vehicle or item of equipment which is not identical to the Federal standard ...<<<#However, it is permissible, if a manufacturer wishes, for him to place Pennsylvania labeling on the reverse side of the hose.#It is the responsibility of the manufacturer to certify that his products comply with Standard No. 106. You may conduct a test program, or you may hire an independent test laboratory to conduct the test program for you. One test laboratory in the United States which tests brake hose is VPI of Blacksburg, Virginia. The National Highway Traffic Safety Administration does not conduct certification tests, but it dies conduct tests on manufacturer products to enforce compliance.#In answer to your March 25 letter, the hydraulic brake hose marking in 'Face A' appears to conform to the requirements of S5.2.2, assuming that letter 'size' refers to letter height. Notice 10 permits the manufacturer designation to be other than block capital letters. 'Face B' is not regulated by our standard.#With regard to the brake hose end fitting and brake hose assembly examples, they appear to conform to S5.2.3 and S5.2.4 if the letter 'size' refers to letter height. It should be noted that Notice 10 excludes labeling of two-piece fitting and certain assemblies and that the next notice may make further modifications.#With regard to vacuum brake hose, your 'Face A' example appears to conform to S5.2.2. if letter 'size' refers to letter height. S5.2.1 is not applicable and therefore the strip is not required. 'Face B' is not regulated by our standard.#Yours truly,Richard B. Dyson,Assistant Chief Counsel;

ID: aiam3192

Open
Mr. Sylvester P. Gagnon, 3919 Third Avenue, Sioux city, Iowa 51106; Mr. Sylvester P. Gagnon
3919 Third Avenue
Sioux city
Iowa 51106;

Dear Mr. Gagnon: This responds to your October 22, 1979, letter which was referred to u by the American Association of Motor Vehicle Administrators. In that letter, you ask about your proposed emergency notification system that would use numbers to inform other drivers of a disabled car's mechanical problem.; The National Highway Traffic Safety Administration does not endors specified products. The agency has a safety standard that requires emergency warning devices to be of a uniform construction. That standard is located in Volume 49 of the Code of Federal Regulations, Part 571.125. Emergency warning devices are devices that alert drivers to the presence of a disabled vehicle. Your device, however, is not used to warn drivers of the presence to a disabled vehicle. It would alert drivers to the nature if a vehicle's disability. the agency concludes, therefore, that you would not be prohibited from offering this device for sale as motor vehicle equipment.; Sincerely, Frank Berndt, 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.