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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 1581 - 1590 of 16517
Interpretations Date

ID: aiam5319

Open
Mr. Michinori Hachiya Director, Technical Affairs Nissan North America, Inc. 750 17th Street, N.W. Suite 901 Washington, D.C. 20006-4607; Mr. Michinori Hachiya Director
Technical Affairs Nissan North America
Inc. 750 17th Street
N.W. Suite 901 Washington
D.C. 20006-4607;

Dear Mr. Hachiya: This responds to your request for an interpretatio of the theft prevention standard (49 CFR part 541) as it would apply to high theft passenger motor vehicles and their replacement parts from model year (MY) 1996 and thereafter. Because the agency has not yet published regulations for MY 1996 high theft lines and thereafter, we are unable to answer your specific questions. As a result of the 'Anti Car Theft Act of 1992' (ACTA), certain changes must be made to the theft prevention standard. In its October 25, 1993 semiannual regulatory agenda, NHTSA listed its proposed rulemakings to implement the ACTA. (See 58 FR 56734 et seq.) In a Federal Register document of January 6, 1994 (59 FR 796), NHTSA stated it intended that the new ACTA-mandated procedures apply to high theft lines beginning in MY 1996. As indicated in the October 1993 semiannual agenda, NHTSA will shortly issue a notice of proposed rulemaking to amend the theft prevention standard. We believe the NPRM will address the issues you raise. If the NPRM does not address them, you will be able to discuss any questions you may have in your comments on the rulemaking submitted to NHTSA during the public comment period. If you have any questions, please contact Dorothy Nakama of my staff at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel;

ID: aiam2126

Open
Interps. File, Part 575.104; Interps. File
Part 575.104;

Subject: Telephone call from Patrick Raher, Esq. of Hogan & Hartson Esqs., representing Mercedes-Benz, on September 15, 1975; The subject telephone call was referred to me by Mark Schwimmer. explained to the caller the status of the UTQGS litigation, the briefing schedule, and the meaning of the stay order. He stated that Mark Schwimmer had read to him the text of Judge Weick's stay order.; The caller's questions and my responses were essentially the same a those covered in my August 27, 1975 memorandum in reference to telephone calls from Yokohama Tire Company and Transportation, Inc.; From: Allan Kam, Attorney

ID: aiam2576

Open
Honorable Warren G. Magnuson, Chairman, Committee on Commerce, Science, and Transportation, United States Senate, Washington, DC 20510; Honorable Warren G. Magnuson
Chairman
Committee on Commerce
Science
and Transportation
United States Senate
Washington
DC 20510;

Dear Mr. Chairman: This is in response to your letter of April 11, 1977, expressing you concern over a perceived pattern of delay in the implementation of the Federal motor vehicle safety and damageability standards. You expressed particular concern about the National Highway Traffic Safety Administration's (NHTSA) recent proposal to delay for one year the effective date for the second phase of requirements in the Part 581 bumper standard.; I am aware that there have been instances in the past when th effective dates of final rules have been delayed or when the final rules have been modified or rescinded. I do not intend to pass judgment on whether the actions of my predecessors in those particular instances should have been taken. However, I agree with your view that changes in the substantive requirements and effective dates of final rules can have undesirable effects and should be avoided if possible.; I believe that the most effective means of reducing the necessity fo changes in final rules is to ensure that each proposed rule is thoroughly examined prior to issuance in final form. Every significant issue should be explored and comments and data from all interested persons should be carefully analyzed. Where gaps in our knowledge appear, the information-gathering authority given the NHTSA should be utilized. For example, extensive use of that authority has been recently made in connection with rulemaking under Title V of the Motor Vehicle Information and Cost Savings Act, as amended, to establish average fuel economy standards for model year 1981-1984 passenger automobiles. By making more careful analyses and obtaining needed information, we can minimize the possibility that belatedly discovered information or circumstances will necessitate a change in our requirements or implementation schedules.; Our taking these steps does not, of course, mean that there will no continue to be some instances in which effective dates and substantive requirements are changed. We must be responsive to new information and changed circumstances to ensure that our requirements continue to meet all statutory criteria. There will still be problems not completely foreseen by the agency or the manufacturers. New concerns such as those relating to fuel economy and noise will arise. Finally, there may be a need to adjust our standards to accommodate changes in other types of motor vehicle standards.; As to the second phase of the bumper requirements, I am currentl reviewing the reasons for the proposal to delay, and the comments on the notice are being analyzed. The statute, under which Part 581 was promulgated, requires that interested persons be given an opportunity for oral presentation of comments prior to the issuance of any amendment to the bumper standard. Thus, my decision on the proposed amendment will be made following a public hearing which will be scheduled in the near future.; Sincerely, Joan B. Claybrook

ID: aiam2063

Open
Mr. Andrew W. Brainerd, Brainerd & Bridges, 1 North LaSalle Street, Chicago, Illinois 60602; Mr. Andrew W. Brainerd
Brainerd & Bridges
1 North LaSalle Street
Chicago
Illinois 60602;

Dear Mr. Brainerd: #This is in response to the May 26, 1975, petitio of your client, Kugelfischer Georg Schaefer & Co., for an amendment of the banding requirement of Federal Motor Vehicle Safety Standard No. 106-74, *Brake Hoses*. #The National Highway Traffic Safety Administration has granted the petitions of General Motors Corporation and Ford Motor Company to delete the banding requirement. A proceeding respecting the issuance of a notice of proposed rulemaking has been commenced. Because the amendment requested by your client is inconsistent with the deletion of the banding requirement, in the strict sense, that petition is hereby denied. You may find, however, that the change now being developed in our rulemaking proceedings will be satisfactory to your client. #Sincerely, Robert L. Carter, Associate Administrator, Motor Vehicle Programs;

ID: aiam2599

Open
Mr. R.G. Wilkins, Product Safety & Reliability Analyst, Grove Manufacturing Company, Shady Grove, Pennsylvania 17256; Mr. R.G. Wilkins
Product Safety & Reliability Analyst
Grove Manufacturing Company
Shady Grove
Pennsylvania 17256;

Dear mr. Wilkins: This responds to your February 17, 1977, letter, concerning Nationa Highway Traffic Safety Administration's (NHTSA) tire labeling requirements contained in Standard No. 120, *Tire Selection and Rims for Motor Vehicles Other Than Passenger Cars*. You address the situation in which it is not practicable to affix the information label to the door.; Location of vehicle certification labels and tire information labels i governed by Part 567.4(c). This section provides that the primary location of the required labels is either the hinge pillar, door-latch post, or door edge that meet the door-latch post, next to the drivers seating position, or if none of these locations is practicable, to the left side of the instrument panel. Further, if none of the above locations is practicable, you may request an alternate location from the agency. I am enclosing a copy of Part 567 explaining how to request an alternate location for the information label.; Sincerely, Joseph J. Levin, Jr., Chief Counsel

ID: aiam2433

Open
Mr. James M. Kommers, P.O. Box 1, Gallatin Block-40 E. Main, Bozeman, MT 59715; Mr. James M. Kommers
P.O. Box 1
Gallatin Block-40 E. Main
Bozeman
MT 59715;

Dear Mr. Kommers: This is in response to your letter of October 12, 1976, requestin information concerning the application of Federal standards to bumper systems produced as after-market replacement equipment.; Standard No. 215, *Exterior Protection*, is a motor vehicle safet standard that applies to the performance of bumper systems on cars manufactured after certain dates. The requirements of the standard are not imposed on the manufacturers of bumpers as items of equipment. It is the manufacturer of the car who must certify the compliance of the bumper system with the provisions of Standard 215. Therefore the bumpers manufactured by Mr. Coddou do not fall within the application of the standard.; Section 108 of the National Traffic and Motor Vehicle Safety Act (Pub L. 89-563), as amended (Pub. L. 93-492), prohibits any manufacturer, distributor, dealer, or motor vehicle repair business from knowingly rendering inoperative any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with a motor vehicle safety standard. Thus, even though a replacement bumper is not required to meet the requirements of Standard 215 when it is produced or sold, its installation on a car by one of the above-named persons would invoke the application of section 108 of the Act. With the bumper installed, the car must comply either with the particular safety standard in effect at the time of its manufacture or with the standard in effect at the time the bumper is replaced.; Due to the requirements of section 108 it would be advisable for Mr Coddou to manufacture his bumpers so that they are capable of meeting the requirements of the applicable Federal bumper standard.; Mr. Coddou should note that although Standard 215 is currentl applicable to all passenger cars, a new and more stringent bumper standard, 49 CFR Part 581, *Bumper Standard*, will become effective September 1, 1978. Part 581 is promulgated under the authority of both the National Traffic and Vehicle Safety Act and the Motor Vehicle Information and Cost Savings Act (Pub. L. 92-513) and will supplant Standard 215 when it becomes effective. I have enclosed copies of both Standard 215 and Part 581 for Mr. Coddou's information.; Sincerely, John Womack, Assistant Chief Counsel

ID: aiam3672

Open
The Honorable David L. Boren, United States Senate, Washington, DC 20510; The Honorable David L. Boren
United States Senate
Washington
DC 20510;

Dear Senator Boren: This responds to your recent letter requesting information on behalf o one of your constituents, Mr. John H. Kiser. Mr. Kiser is concerned about the growing practice of persons installing privacy glass' or one-way plastic films' on passenger car windows. He believes this is a dangerous practice because it prevents law enforcement officers and other drivers from seeing inside the vehicles. Mr. Kiser thinks there should be Federal laws to prevent such installations in passenger cars.; A Federal regulation already exists which, under certain circumstances precludes the practice referred to by Mr. Kiser. The National Highway Traffic Safety Administration has the authority to govern the manufacture of new motor vehicles and motor vehicle equipment. Pursuant to the National Traffic and Motor Vehicle Safety Act, we have promulgated Federal Motor Vehicle Safety Standard No. 205, *Glazing Materials*, which specifies performance and location requirements for glazing used in vehicles. These requirements include specifications for minimum levels of light transmittance (70 percent in areas requisite for driving visibility, which includes all windows in passenger cars) and abrasion resistance. This specification for light transmittance precludes darkly-tinted windows in new automobiles.; The agency has stated in past interpretations that solar films such a the type referred to in Mr. Kiser's letter are not glazing materials themselves, and would not have to comply with Standard No. 205. However, installation of such films on new motor vehicles would be prohibited if the vehicle glazing no longer complied with the light transmittance or abrasion requirements of the standard. If a vehicle manufacturer or a dealer places the film on glazing in a vehicle prior to sale of the vehicle, that manufacturer or dealer has to certify that the glazing continues to be in compliance with the requirements of Standard No. 205. Section 108(a)(1) prohibits any person from offering for sale or selling any motor vehicle or equipment that fails to comply with applicable safety standards.; After a new vehicle has been sold to the consumer, he may alter hi vehicle as he pleases, so long as he adheres to all State requirements. Under Federal law, the owner could install the tinting film on glazing in his vehicle whether or not such installation adversely affected the light transmittance and abrasion resistance of his vehicle's glazing. It should be noted, however, that section 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act provides that no manufacturer, distributor, dealer or motor vehicle repair business shall knowingly render inoperative any device or element of design installed on or in a motor vehicle in compliance with an applicable motor vehicle safety standard. Render inoperative' means to remove, disconnect or degrade the performance of a system or element of design installed pursuant to the Federal safety standards. Thus, none of those persons may knowingly install a solar film on a vehicle for its owner if that act would render inoperative the light transmittance or abrasion resistance of the vehicle glazing. Whether this would be the case would have to be determined by the person making the installation. Violation of this section can result in Federal civil penalties up to $1,000 for each violation.; The preceding discussion regarding tinting films would be equall applicable to one-way privacy glass,' if such glass did not have a luminous transmittance of at least 70 percent. This means that such glass could not be installed by a dealer on new passenger cars prior to their first sale, nor by the persons mentioned in section 108(a)(2)(A), on used vehicles, to replace complying glazing.; The individual States must govern the operational use of vehicles b their owners since the agency does not have authority in this area. Thus, it would be up to the States to preclude owners from applying films or one-way glass on their own vehicles. Mr. Kiser may wish to contact the National Committee on Uniform Traffic Laws (555 Clark Street, Evanston, Illinois 60204) to find out which States have laws that would preclude owners from placing solar film on their automobile windows.; I am enclosing a copy of Safety Standard No. 205 for Mr. Kiser' information. Please contact Hugh Oates of my staff if you have any further questions (202-426-2992).; Sincerely, Frank Berndt, Chief Counsel

ID: aiam2960

Open
Mr. Charles J. Calvin, President, Truck Trailer Manufacturers Association, 2430 Pennsylvania Avenue, N.W., Washington, DC 20037; Mr. Charles J. Calvin
President
Truck Trailer Manufacturers Association
2430 Pennsylvania Avenue
N.W.
Washington
DC 20037;

Dear Mr. Calvin: We regret the delay in responding to your April 18, 1978, lette criticizing the National Highway Traffic Safety Administration's (NHTSA) interpretation concerning the responsibility of a manufacturer for ensuring that its vehicles will not be overloaded when transporting materials for which they are designed. In that interpretation, the agency indicated that a vehicle whose tank cargo volume is of such size that it misrepresents the assigned GVWR and GAWR values of that vehicle, thus, inviting overloading might be considered to have a safety related defect. Please permit me to qualify the interpretation in the light of your criticism.; The NHTSA realizes that overloading is a problem created for the mos part by the operator of a vehicle. Accordingly, it is not intended by the agency's interpretation or regulations to hold a vehicle manufacturer responsible for every situation in which a vehicle is overloaded. Most any type truck can be overloaded by the user. An operator should be aware of this possibility, however, given the amount of space on that vehicle on which cargo can be loaded and the broad range of cargo that can be transported by that vehicle. If a truck designed for the transportation of one specific cargo were misused by the operator to transport another type of cargo not intended by the vehicle manufacturer, then any resultant overloading would be the responsibility of the operator not of the manufacturer. However, when a vehicle designed to transport a specific cargo can be overloaded when filled to its capacity with that cargo, the NHTSA has determined this to be a problem created by the vehicle manufacturer and would consider taking action against a manufacturer to correct the problem. This agency's interpretation that a vehicle be able to safely transport its intended design cargo when fully loaded is an objective and unambiguous requirement and simply places the burden upon a manufacturer to ensure that the design cargo does not exceed the GAWR and GVWR.; Specifically we are concerned that a tank of fixed volumetric capacit could be loaded to exceed the vehicle's GAWR and GVWR values when filled with a commodity of design density simply because of the tank being too large.; When there is reason to believe that the density of a cargo likely t be transported could present a vehicle overloading problem, the manufacturer has a duty to provide a warning and information as a precaution in averting the potential hazard. The NHTSA does not object to the practice of partial loading of tankers and tank compartments for remaining within safe loading limits provided guidelines are furnished by manufacturers for performing approved loading operations. Prescribed precautions hopefully will counteract any tendency to perceive volume as the load limiting criterion. We would agree that loading information as contained in your enclosure would be a satisfactory means of conveying safety information and could be referenced on a conspicuous vehicle label.; Sincerely, Frank Berndt, Acting Chief Counsel

ID: aiam3388

Open
Neal J. Patten, Esq., Messrs. Patten & Wornom, P.O. Box 725, Newport News, Virginia 23607; Neal J. Patten
Esq.
Messrs. Patten & Wornom
P.O. Box 725
Newport News
Virginia 23607;

Dear Mr. Patten: This replies to your letter of December 23, 1980 to the General counse asking if the 'Cool Gear' motorcycle helmet 'has been certified by the Department and whether or not it has met the Z-90.1 1973 standards'.; The Department does not certify motor vehicles or equipment and has n knowledge of whether the Cool Gear meets the Z-90.1 11973 standards.; Any 'Cool Gear' motorcycle helmet that fits head form size C i required, however, to comply with 49 CFR 571.218 (Motor Vehicle Safety Standard No. 218), which incorporates the essence of the Z-90.1 1971 standards, and to bear the manufacturer's own certification of compliance (see paragraph S5.6.1(5), and 15 U.S.C. 1403). The agency has not tested any 'Cool Gear' for compliance with Standard No. 218.; Sincerely, Frank Berndt, Chief Counsel

ID: aiam3222

Open
Mr. William A. Bertolini, President, Bertolini Engineering Co., Inc., Star Route One, Vernon, NJ 07462; Mr. William A. Bertolini
President
Bertolini Engineering Co.
Inc.
Star Route One
Vernon
NJ 07462;

Dear Mr. Bertolini: This is in reply to your letter of February 22, 1980, asking for a interpretation of Federal Motor Vehicle Safety Standard No. 108.; You have referenced our letter of May 5, 1977, to Mr. Dennis Moore o Dry Launch. That letter interpreted S4.3.1.1.1 with respect to a rear clearance lamp which indicated overall width though it was not located on the rear of the trailer. In that position it was not required to be visible at 45 degrees inboard. You have asked whether the same inboard visibility requirements may be eliminated for front clearance lamps 'for the same reasons'.; The answer is yes. If a front clearance lamp that indicates overal width is not located at the front of the trailer, S4.3.1.1.1 relieves it of the requirement that it be visible at 45 degrees inboard.; I hope this answers your question. 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.

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