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: aiam1557OpenMr. P.K. Kamath, Senior Safety Engineer, Oshkosh Truck Corporation, P.O. Box 2566, Oshkosh, WI 54901; Mr. P.K. Kamath Senior Safety Engineer Oshkosh Truck Corporation P.O. Box 2566 Oshkosh WI 54901; Dear Mr. Kamath:#This is in reply to your letter of July 9, 1974 asking whether Standard No. 101 requires identification and illumination of an emergency engine stop control, in addition to the engine stop control intended for normal use.#The 'engine stop' control referred to in Standard No. 101 means any control used to stop the engine, and would include the emergency control. If it is important for the normal control to be identified and illuminated, it is all the more important that a control intended for emergency use meet the requirements of the standard. Identification such as 'emergency engine stop' would be acceptable under Standard No. 101. Illumination, of course, must meet the requirements of the standard, but since you have not described the emergency system or its location we cannot offer a more precise comment.#Yours truly, Richard B. Dyson, Acting Chief Counsel; |
|
ID: aiam3090OpenMr. Karl-Heinz Ziwica, Safety & Emission Control Engineering, BMW of North America, Inc., Montvale, New Jersey 07645; Mr. Karl-Heinz Ziwica Safety & Emission Control Engineering BMW of North America Inc. Montvale New Jersey 07645; Dear Mr. Ziwica: This is in reply to your letter of May 16, 1979, to Mr. Schwartz of m office, and in confirmation of your subsequent telephone conversation with him.; You wish to know whether Federal Motor Vehicle Safety Standard No. 115 *Vehicle identification number*, permits BMW to use all the permissible numerical digits in the 11th position of the vehicle identification number (VIN) for each of its two plants, as long as each VIN in its entirety assigned to each individual vehicle uniquely identifies its plant of manufacture. A system such as you suggest was proposed in the notice of proposed rulemaking for this standard issued on January 16, 1978 (Docket No. 1-22, Notice 4, 43 FR 2189). The response to this particular proposal was negative, and the rule issued on August 17, 1978, withdrew it. Consequently, the 11th character of the VIN must in and of itself be decipherable into the plant of manufacture (S4.5.3.2).; This is not to say, however, that BMW does not have considerabl flexibility in its utilization of the 11th position. A pointed out in Notice 8 (44 FR 17489, March 22, 1979), BMW can submit more than one character to represent a single plant. While this restriction unfortunately may result in some change to the system which BMW is currently employing, the agency believes that a sophisticated allotment of sequential blocks will alleviate at least some of the problems which you foresee.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam4755OpenMr. Ken Stone Automotive Safety Engineering Canewdon Consultants Group Limited The Maltings, Locks Hill South Street Rochford, Essex SS4 1BB England; Mr. Ken Stone Automotive Safety Engineering Canewdon Consultants Group Limited The Maltings Locks Hill South Street Rochford Essex SS4 1BB England; Dear Mr. Stone: This is in response to your telefax to Barry Felrice Associate Administrator for Rulemaking, concerning the definition of a walk-in van. I apologize for the delay in responding to your inquiry. You requested a definition of the term 'walk-in van,' particularly with regard to floor to roof height requirements, bulkhead requirements, step height requirements, and the presence of a front passenger seat. Although Federal Motor Vehicle Safety Standard No. 208 uses the term to describe a specific type of vehicle, neither that standard nor any other agency regulation defines the term. None has been necessary to date since the term is largely self-defining. For a vehicle to be regarded as meeting the term, it must be possible for a person to enter the occupant compartment in an upright position. Examples of walk-in vans include the GMC Step Van, and the large delivery vans used by the U.S Postal Service and the United Parcel Service in this country. If you need further information concerning whether the vehicle you propose to import would be considered a walk-in van, I suggest that you provide this office with information concerning the configuration and dimensions of the vehicle. Photographs of its interior and exterior would be helpful as well. I hope you have found this information useful. Sincerely, Paul Jackson Rice Chief Counsel; |
|
ID: aiam1107OpenMr. John W. Leask, President, Engineering Dynamics Corp., 314 Great Road, Bedford, MA 01730; Mr. John W. Leask President Engineering Dynamics Corp. 314 Great Road Bedford MA 01730; Dear Mr. Leask: This is in response to your letter of March 26, 1973, concerning th test procedures of Motor Vehicle Safety Standard No. 215, *Exterior Protection.*; The test procedures of a motor vehicle safety standard prescribe th manner in which the NHTSA will test a vehicle. If a vehicle fails in our tests, the manufacturer may be subject to civil penalties unless he can establish that he exercised due care in manufacturing the vehicle. To establish due care he would have to demonstrate the steps he took to assure himself that the vehicle would comply when tested in accordance with the standard.; In the case of Standard No. 215, the agency will conduct its impac tests by using the pendulum specified in S6.2 of the standard. A manufacturer will not fail the standard if he does not use a pendulum. He may, if he chooses, test his vehicle by using a different device if he feels confident that the device he uses is equivalent in all relevant respects to the pendulum. If his vehicle fails in our pendulum tests, he will have to demonstrate the equivalency of his test device if he hopes to establish a defense in a proceeding brought by the agency.; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam4305OpenMr. Takashi Shimoda, Chief of Quality Assurance Section, Nichirin Rubber Industrial Co., Ltd., 1118, Sazuchi, Bessho-cho, Himeji-City, 671-02, JAPAN; Mr. Takashi Shimoda Chief of Quality Assurance Section Nichirin Rubber Industrial Co. Ltd. 1118 Sazuchi Bessho-cho Himeji-City 671-02 JAPAN; Dear Mr. Shimoda: This responds to your letter to our office asking two questions abou Federal Motor Vehicle Safety Standard No. 106, *Brake Hoses.* I am pleased to be of assistance.; In your letter, you explain that your company plans to export brak hose assemblies to the United States that are made of resin and other materials. You first ask whether Standard No. 106 applies 'equally' to all brake hoses and assemblies regardless of the materials used in their manufacture. Your understanding is correct. Brake hoses and brake hose assemblies may be made from any material as long as they can meet all applicable performance requirements of the standard.; Your second question concerns the standard's whip resistanc requirement of S5.3.3 and the whip resistance test of S6.3. You ask for confirmation that cracks in the hose specimen are acceptable under S5.3.3 provided that there is no leakage for the hose assembly. Your understanding is correct. S5.3.3 states: 'A hydraulic brake hose assembly shall not rupture when run continuously on a flexing machine for 35 hours (S6.3).' The standard defines 'rupture' as 'any failure that results in separation of a brake hose for its end fitting or in leakage.' The determining factor for the whip resistance requirement is thus the pressure maintained by the system. If there is no pressure loss in the system, the brake hose assembly meets S5.3.3, regardless of the presence of cracks in the hose specimen. Please not, however, that although cracks in themselves do not constitute a failure of S5.3.3, the development of cracks caused by exposure to ozone is important for the ozone resistance requirement of S5.2.10.; Since you are planning to import your products into the United States I am enclosing copies to two procedural rules which apply to all manufacturers subject to the regulations of this agency. The first is 49 CFR Part 566, *Manufacturer Identification.* This rule requires your company to submit its name, address and a brief description of the items of equipment it manufactures to this agency within 30 days after it imports its products into this country.; The other rule is 49 CFR 551, *Procedural Rules.* Subpart D of thi regulation requires all manufacturers headquartered outside of the United States to designate a permanent resident of the United States as the manufacturer's agent for service of all process, notices, orders, and decision. This designation should be mailed to the Chief counsel, National Highway Traffic Safety Administration, 400 Seventh Street, S.W., Washington, D.C. 20590, and must include the following information:; 1. A certification that the designation of agent is valid in form an binding on the manufacturer under the laws, corporate-by-laws, or other requirements governing the making of the designation at the time and place where it is made,; 2. The full legal name, principal place of business and mailing addres of the manufacturer,; 3. Marks, trade names, or other designations of origin of any of th manufacturer's products which do not bear its name,; 4. A statement that the designation shall remain in effect unti withdrawn or replaced by the manufacturer,; 5. A declaration of acceptance duly signed by the agent appointed which may be an individual, a firm or a United States corporation, and,; 6. The full legal name and address of the designated agent. In addition, the designation must be signed by a person with authorit to appoint the agent. The signer's name and title should be clearly indicated beneath his or her signature.; I hope this information is helpful. Please contact us if you hav further questions.; Sincerely, Erika Z. Jones, Chief Counsel |
|
ID: aiam1392OpenMr. George C. Nield, Engineering Advisor, Busby(sic) Rivkin(sic) Sherman(sic) Levy and Rehm, 816 Connecticut Avenue, N.W., Washington, DC 20006; Mr. George C. Nield Engineering Advisor Busby(sic) Rivkin(sic) Sherman(sic) Levy and Rehm 816 Connecticut Avenue N.W. Washington DC 20006; Dear Mr. Nield: This is in reply to your letter of December 13, 1973, asking whethe glazing in the rear quarter windows of the Datsun model HLB-210 may, consistently with Motor Vehicle Safety Standard No. 205, be manufactured of AS 3 glazing material. This depends, as you point out, on whether this glazing is used 'at levels requisite for driving visibility' under American National Standards Institute Standard ANS Z26.1-1966, incorporated into Standard No. 205. You refer in your letter to section 1017(a) of the California Vehicle Code which states:; >>>Side windows to the rear of the driver and the rear windows not use for vision directly to the rear are not considered areas requisite for driving visibility.<<<; The locations where the use of AS 3 glazing is permitted are set fort on page 12 of ANS Z26. AS 3 glazing may be used, 'anywhere in a motor vehicle except in passenger car windshields and in the following locations at levels requisite for driving visibility....(2) *Passenger automobiles and taxicabs*. Glazing of *all* windows including rear window, *all* interior partitions, and *all* apertures created for window purpose. (emphasis added); The only exclusion from the broad prohibition against the use of AS glazing in passenger cars is 'at levels not requisite for driving visibility.' We do not agree with the California Code provision. We consider the word 'levels' in Standard 205 to mean vertical heights in relation to the driver's eyes. We, therefore, cannot concur in the application of the 'levels requisite for driving visibility' concept as it appears in Standard No. 205 to complete windows or other glazing areas of passenger cars.; With respect to the Datsun model in question, there is no evidence i your letter that the windows in question are not at a level requisite for driving visibility. In fact, they appear to include levels of a driver's normal eye point.; The NHTSA presently hopes to publish a revised notice of propose rulemaking regarding direct fields of view in the fall of 1974. Previous proposals regarding this subject were withdrawn by notice published March 7, 1973 (38 FR 6194).; Yours truly, Richard B. Dyson, Assistant Chief Counsel |
|
ID: aiam3655OpenThe Honorable Eldon Rudd, House of Representatives, Washington, DC 20515; The Honorable Eldon Rudd House of Representatives Washington DC 20515; Dear Mr. Rudd: This responds to your recent letter on behalf of your constituent, Mrs Jan Wilson, asking whether Federal law restricts motorists from having darkly tinted films installed on the windows of their automobiles.; The National Highway Traffic Safety Administration has authority t govern the manufacture of new motor vehicles and motor vehicle equipment. 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. Seventy percent transmittance is required in all areas requisite for driving visibility, which includes the windshield and all windows in passenger cars. This specification for light transmittance precludes darkly-tinted windows in new automobiles.; The agency has stated in past interpretations that solar films are no glazing materials themselves, and would not have to comply with Standard No. 205. However, use of such films on motor vehicles in certain cases would be prohibited if the vehicle glazing no longer complied with the light transmittance requirements of the standard (most of these films do reduce light transmittance below 70%). If a vehicle manufacturer or 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 (i.e., has to certify that the glazing still has a transmittance of at least 70%).; Regarding vehicles that have already been purchased, sectio 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1381) 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. Thus, none of those persons may knowingly install a solar film on a vehicle for its owner if the vehicle glazing would no longer meet the light transmittance requirements of Standard No. 205. Whether this would be the case would have to be determined by the person making the installation. Violation of this provision could subject the manufacturer, distributor, dealer, or motor vehicle repair business to civil penalties up to $1,000 for each violation.; Please note, however, that under Federal law the vehicle owner ma alter his or her vehicle as is desired. This agency does not govern use of vehicles by owners, this is left to the States. Thus, under Federal law, an owner could install solar film on his or her vehicle whether or not such installation affected compliance with Standard No. 205.; In summary, Federal law does not preclude Mrs. Wilson from havin darkly tinted film on her passenger car, provided she installed the film herself. However, if a manufacturer, dealer, distributor or motor vehicle repair business (including an auto tint shop) installed the film for Mrs. Wilson, they are in violation of Federal law if the glazing no longer meets the 70% light transmittance requirements of Standard No. 205. The State of California is, of course, free to prohibit vehicle owners from operating vehicles with darkly tinted glazing in its jurisdiction.; Sincerely, Frank Berndt, Chief Counsel |
|
ID: aiam1668OpenMr. Max L. Hill, Camping Trailer Division, Coleman Company, Incorporated, P. O. Box 111, Somerset, PA 15501; Mr. Max L. Hill Camping Trailer Division Coleman Company Incorporated P. O. Box 111 Somerset PA 15501; Dear Mr. Hill: This is in acknowledgment of your Defect Information Report, i accordance with the defect reporting regulations, Part 573.; The Defect Information Report involves: 1,100 - 1975 Valley Forg camping trailers with McCreary tires size 5.70-8 which may experience tread delamination.; The following National Highway Traffic Safety Administratio identification number has been assigned to the campaign *74- 0206*. The first quarterly status report for this campaign is required to be submitted by February 5, 1975. Please refer to the above number in all future correspondence concerning this campaign.; The letter which you have sent to the owners of the subject vehicle does not contain the precise language which is required by Part 577 (49 CFR), the Defect Notification regulation. A copy of this regulation is enclosed. Specifically, the second sentence of your letter describes the defect as existing in the tires, where it should have described the defect as existing in the vehicle itself. The reference to 'item of motor vehicle equipment' in Part 577 applies only to equipment campaigns where vehicles are not involved.; Since this discrepancy in your notification letter does not appear t discourage owner response, mailing of a revised letter will not be required. It is hoped that these comments will assist you in the event that another defect notification campaign becomes necessary at some time in the future.; Sincerely, Andrew G. Detrick, Acting Director, Office of Defect Investigation, Motor Vehicle Programs; |
|
ID: aiam4190OpenMr. Ron Marion, Specification Engineer, Thomas Built Buses, L.P., P.O. Box 2450, High Point, NC 27261; Mr. Ron Marion Specification Engineer Thomas Built Buses L.P. P.O. Box 2450 High Point NC 27261; Dear Mr. Marion: This responds to your May 21, 1986 letter requesting an interpretatio of Federal Motor Vehicle Safety Standard No. 222, *School Bus Passenger Seating and Crash Protection*, as it applies to safety belts on large school buses. You asked first whether it is acceptable to install two safety belts on a 39-inch bench seat. Your second question asked whether such a seat would be designated as a two- or three- passenger seat.; In response to your first question, Standard No. 222 currently does no prohibit you from providing two safety belts on a 39-inch bench seat. This is because NHTSA does not require or set specifications for safety belts installed for passengers on large school buses, but for the requirement that the installation method not interfere with vehicles' compliance with applicable motor vehicle safety standards. However, the agency is currently considering an amendment to Standard No. 222 which would affect the voluntary installation of safety belts on 39-inch bench seats. If we adopt changes to the standard proposed in a notice published on October 10, 1985, safety belts voluntarily installed on large school buses must meet requirements similar to those established for safety belts on small school buses. Under the proposed requirements, manufacturers voluntarily installing safety belts would have to install three safety belts on a 39-inch seat. We are currently evaluating comments received on the proposal, and final action is anticipated in the near future.; In response to your second question, since your current option t install voluntarily two safety belts on a 39-inch bench seat does not affect your responsibility under the National Traffic and Motor Vehicle Safety Act to manufacture school buses which comply with all applicable requirements of Standard No. 222, the 39-inch bench seat to which you refer must be designated as a 3-passenger seat under S4.1 of the standard. You as a manufacturer must ensure that the seat meets the forward and rearward performance requirements, and other applicable requirements of Standard No. 222, based on calculations of *three* seating positions and the requisite force applications. While your bench seat might be occupied by fewer persons due to the safety belts, that calculation helps to assure that the seat provides adequate protection when occupied by the maximum number.; We note further that since under S4.1 a 39-inch bench seat i considered to have three designated seating positions, manufactures must not provide more than three safety belts on a 39-inch bench seat or otherwise imply that the seat is capable of carrying more than three passengers.; If you have any further questions, please let us know. Sincerely, Erika Z. Jones, Chief Counsel |
|
ID: aiam2947OpenMr. Melvin Ives, President, United Bus Sales, Inc., 6700 S. Garfield Avenue, Bell Gardens, CA 90201; Mr. Melvin Ives President United Bus Sales Inc. 6700 S. Garfield Avenue Bell Gardens CA 90201; Dear Mr. Ives: This responds to your November 6, 1978, letter asking for a interpretation of the warning buzzer requirement of Standard No. 217, *Bus Window Retention and Release*.; The standard requires a warning buzzer to sound when an emergency doo release mechanism is not in the closed position and the vehicle's ignition is on. From conversations with you and our Office of Vehicle Safety Compliance, we have determined that your rear emergency door uses a warning buzzer that sounds when the door release mechanism is not in the closed position unless someone continues to exert pressure to hold the door closed. The National Highway Traffic Safety Administration considers such a warning device to be in compliance with the standard. The purpose of the warning alarm is to warn passengers and the driver when a door is accidentally left in the open condition while the vehicle ignition is in the on position. You device appears to meet the intent of the standard.; We have discussed this issue with Mr. Jerry Alexander of the Californi Highway Patrol, and he has indicated that he will accept our determination. We are sending him a copy of this letter for his information.; Sincerely, Joseph J. Levin, Jr., 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.