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 |
|---|---|
ID: nht92-6.9OpenDATE: June 11, 1992 FROM: Paul Jackson Rice -- Chief Counsel, NHTSA TO: Hal Balzak TITLE: None ATTACHMT: Attached to letter dated 12/3/91 from Hal Balzak to NHTSA, U.S. DOT TEXT: This responds to your letter concerning Federal Motor Vehicle Safety Standard No. 201, Occupant Protection in Interior Impact. I apologize for the delay in our response. You stated that you have received a copy of this standard and would like clarification of two issues. Your questions are addressed below. Your first question asked whether Standard No. 201 applied to passenger cars manufactured between January 1, 1968 and September 1, 1981. The answer to this question is yes; the standard applied to all passenger cars manufactured on or after January 1, 1968. Your second question asked whether Standard No. 201 applies to instrument panels manufactured for replacement of damaged units. The answer to this question is that, by its own terms, Standard No. 201 applies only to new motor vehicles. This means that the standard applies to original equipment components, including instrument panels, but not to replacements for those components. However, you should be aware of an important provision in Federal law. Section 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1397(a)(2)(A)) provides that "(n)o manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal Motor vehicle safety standard. . . ." This provision applies to both new and used vehicles. You specifically asked about the replacement of damaged instrument panels. I note that the Safety Act does not require a manufacturer, distributor, dealer or repair business to return a vehicle to compliance with a standard if a device or element of design has been "rendered inoperative" by another agent, such as a crash. The prohibition of section 108(a)(2)(A) does not apply to individual owners who alter their own vehicles. Thus, individual owners may install any item of motor vehicle equipment regardless of its effect on compliance with Federal motor vehicle safety standards. However, NHTSA encourages vehicle owners not to tamper with the safety equipment installed on their vehicles. I hope this information is helpful. If you have further questions, please feel free to contact Edward Glancy of my staff at (202) 366-2992. |
|
ID: nht92-7.1OpenDATE: May 18, 1992 FROM: Timber Dick -- General Manager, Safeline Children's Products Company TO: Deirdre Fujita -- Office of the Chief Counsel, NHTSA COPYEE: Michael Pyne -- NHTSA Enforcement; Kathleen Weber -- UMTRI TITLE: None ATTACHMT: Attached to letter dated 8/18/92 from Paul J. Rice to Timber Dick (A39; Std. 213) TEXT: We spoke on several occasions recently regarding Safeline's certification of the Sit'n'Stroll 2-in-1 Carseat/Stroller under FMVSS 213. In particular, our discussions focused on NHTSA's interpretation of the regulations, and whether a manufacturer could certify a rear-facing carseat at a weight greater than 20 lbs. We were prompted to investigate certification at a higher weight than the standard 20-lb limit as a result of numerous safety studies (several of which are enclosed) which indicate that children are exposed to a lessened risk of cervical spine fractures, and consequent para- and quadriplegia, if they are rearward facing to a higher weight limit. I have a baby boy born with a 99%+ head circumference, and I've been afforded additional peace of mind by keeping him rear-facing in his Sit'n'Stroll as he has reached 25 lbs in body weight. Safeline is committed to providing the highest degree of safety possible within practical and regulatory constraints. To this end, we recently tested the Sit'n'Stroll at the University of Michigan facility rear-facing using a 35 lb, NHTSA-approved dummy. FMVSS 213 positioning procedures were interpreted in a logical manner. The enclosed test results are a powerful testimony to the safety benefits afforded by use of the Sit'n'Stroll in this configuration. Please note two important conclusions of the test. First, even with the 35-lb load, the test seat was well within the back angle limits imposed by FMVSS 213. Our maximum back angle was just 50 degrees, as compared to the maximum permissible of 70 degrees. Second, and in my eyes perhaps more compelling, our Head Injury Criteria was 289, a remarkably low figure as contrasted with the permissible 1000. Safety experts across the nation have contacted Safeline to applaud our efforts to give parents of babies (like mine) with disproportionately large heads an safer way to transport their children. We submit that it is in the best interests of the taxpayers and their children to allow FMVSS 213 interpretations which would permit rear-facing carseats to be certified with 35-lb dummies to a weight higher than 20 pounds. We sincerely appreciate your consideration of this matter. |
|
ID: nht92-7.10OpenDATE: May 8, 1992 FROM: Paul Jackson Rice -- Chief Counsel, NHTSA TO: Bill Willett TITLE: None ATTACHMT: Attached to letter dated 4/17/92 from Bill Willett to NHTSA (OCC 7240) TEXT: This responds to your letter of April 17, 1992, with respect to motor vehicle lighting. You believe that a "flickering brake light is an improvement to the existing dim-bright red light now used." The light you have in mind is one which "flashes on and off at a faster rate than that of the turn signal and emergency flashers." The light is intended "to alert the driver that the brakes are applied as long as the brakes are used . . . ." You have asked "Is there any Federal law preventing me from doing research by adding another device to the vehicle lights." Federal Motor Vehicle Safety Standard No. 108, Lamps, Reflective Devices, and Associated Equipment, requires that stop lamps be steady-burning when the brakes are applied. The National Traffic and Motor Vehicle Safety Act prohibits a "manufacturer, distributor, dealer, or motor vehicle repair business" from any modification that renders wholly or partially inoperative motor vehicle equipment, such as stop lamps, installed pursuant to a standard such as Standard No. 108. Were the existing stop lamps to be rewired to flash, we would regard the change from steady burning to flashing as rendering the stop lamps partially inoperative within the meaning of this prohibition. However, please note that the prohibition includes only four categories of persons, and does not apply to modifications made by a "survey group member" who is not within one of those categories. Nor does it apply to modifications made by a vehicle owner. In addition, you should check with the authorities in Alabama to ensure that your modifications do not violate any provision of the State motor vehicle code. |
|
ID: nht92-7.11OpenDATE: May 8, 1992 FROM: Paul Jackson Rice -- Chief Counsel, NHTSA TO: J.W. Lawrence -- Volvo GM Heavy Truck Corporation TITLE: None ATTACHMT: Attached to letter dated 10/25/91 from J.W. Lawrence to NHTSA Administrator (OCC 6634) TEXT: This responds to your letter of October 25, 1991 requesting information on whether metric sizes and threads for attachment bolts would be considered "equivalent hardware for the requirements of S4.1(f) of Standard No. 209, Seat Belt Assemblies. In general, it is permissible to use metric hardware for the installation of safety belts. However, as explained below, it is unclear whether the metric fastener M12, as described in your follow-up letter of December 13, 1991, is equivalent to the attachment hardware specified in Standard No. 209. The Department of Transportation is implementing the policy of using metric dimensions, in addition to American Standard dimensions, in our regulations. Currently, FMVSS No. 209 "Seat Belt Assemblies," requires the safety belt anchorage bolt to be "7/16-20 UNF-2A or 1/2-13 UNC-2A attachment bolts or equivalent hardware" (S4.1.(f)). The SIZE of the bolt specified in your letter is equivalent to the safety belt anchorage bolt specified in Standard No. 209. Since the M12 nut is approximately halfway between a 7/16 and a 1/2 inch bolt, it is clear that the size would fulfill the requirement of the standard. However, it is not clear from the information provided, whether the class of thread fit of the metric bolt is comparable to the requirements of the standard. The standard does specify a Class 2 bolt. A Class 2 thread provides clearance under all conditions and allows external threads to be plated with no resultant assembly difficulties. This is the most common commercial grade fit. Therefore, if the bolt thread fit is equivalent, we would consider this metric bolt to be equivalent hardware to the bolt specified in Standard No. 209. 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. |
|
ID: nht92-7.12OpenDATE: May 6, 1992 FROM: Paul Jackson Rice -- Chief Counsel, NHTSA TO: Shigeyoshi Aihara -- Manager, Information Services, Ichikoh America, Inc. TITLE: None ATTACHMT: Attached to letter dated 3/16/92 from Shigeyoshi Aihara to Paul J. Rice (OCC 7113) TEXT: This responds to your letter of March 16, 1992, requesting an interpretation of the applicability of the fogging prohibition of S7.4(i)(6) of Federal Motor Vehicle Safety Standard No. 108. Initially, we would like to call your attention to the fact that S7.4 (i)(6), which you quoted in its entirety, was amended on March 11, 1991, to delete the requirement that a headlamp meet the photometric requirements after a humidity test. S7.4 (i)(6) now states in pertinent part that, after a humidity test conducted in accordance with S8.7, "the inside of the headlamp shall show no evidence of delamination or moisture, fogging or condensation visible without magnification." You have attached a drawing of a vented headlamp with an onboard aiming system. The headlamp is available with two different types of bubble indicators. Your first question is: "After the humidity test, both types ... show the fogging in the location as shown in attached sketches. But, this fogging is gone at normal temperature. *** Is such fogging acceptable after the temperature test?" Your second question is whether "'the inside of the housing' means the lens and reflector portions" or "the entire inside portion of headlamps?" The humidity test was adopted in 1983. Allowing humidity or water in headlamps causes slow degradation of the reflector over the long term. The presence of humidity results in spots on the reflector and lens, and eventual photometric failure. The humidity test is designed to assure that the vents in vented headlamps eliminate moisture in the headlamp when exposed to air flow with the headlamps off, thus assuring adequate performance in long term use. The provision for onboard headlamp aiming devices was not adopted until 1989, and did not specify that they be located within the headlamp. From the foregoing, it is evident that the humidity test for replaceable bulb headlamps was not adopted to address a problem inherent in the exposure of onboard aiming devices to moisture. These devices were not in use at the time the humidity test was added to Standard No. 108, and they do not contribute directly to the photometric performance of the headlamp. From the diagram you enclosed, the aiming device appears located behind the reflector. It is not possible to determine from your letter whether moisture forms on the exterior or the interior of the aiming device. Although S7.4 (i)(6) prohibits moisture "inside the headlamp" and the aiming device is located inside the headlamp, we would not read the prohibition as extending to the aiming device if the moisture occurs inside that device. Even if the moisture occurs on the exterior of the aiming device, it does not affect the photometric properties of the headlamp. The agency does not wish to impose inadvertent design restrictions that are not directed towards safety, and therefore regards any moisture that may occur on the exterior of the aiming device as outside the prohibition of S7.4 (i)(6). This interpretation, however, is limited to the specific design that you have presented. |
|
ID: nht92-6.13OpenDATE: June 9, 1992 FROM: Jim Sasser -- United States Senator TO: Jerry R. Curry -- Administrator, NHTSA TITLE: None ATTACHMT: Attached to letter dated 7/7/92 from Frederick H. Grubbe to Jim Sasser (A39; Part 571.3); Also attached to letter dated 5/29/92 from Jerry R. Curry to John J. Duncan, Jr. TEXT: I have been contacted by several Tennesseans regarding their concern about a federal law governing the use of vehicles with a capacity for eleven or more individuals. I have enclosed a sample letter for your reference. Many schools in Tennessee formerly used passenger vans to transport athletic teams and have been forced to discontinue use of the vans due to this law. The elimination of the van service has placed a tremendous financial burden on these schools and forced some to eliminate some of their minor sports programs. Accordingly, I would appreciate your giving careful consideration to this matter and providing me with a report which addresses whose responsibility it is to meet the federal safety standards. Does the individual who sells the van have responsibility or does the school which purchased the vehicle? Moreover, I would further appreciate the report addressing the question of the liability involved in the event of an accident. Thank you for your courtesy and assistance. Attachment Letter dated 5/29/92 from Robert High, Athletic Director, Brainerd High School, Chattanooga, Tennessee to Jim Sasser. Text of letter: Mr. Sasser: Recently there has been much concern in regards to recent memos from Mr. Ernest Farmer, Director of Pupil Transportation, Tennessee Department of Education. The memo I have reference to concerns a law that dates back to 1970's. This memo is a federal law pertaining to the use of vehicles with a capacity of eleven or more passengers. Many schools throughout the state have used both 12 and 15 passenger vans to transport their athletic teams to and from athletic events. There are several systems that have been required to stop using their vans for transportation in athletics due to that law. This situation has and could create a tremendous financial burden on schools, a problem we already have due to budget cuts. If vans are eliminated from schools, I foresee several problems. Several schools would have to eliminate most of their minor sports simply because of the cost for renting buses on a daily basis. Also, the availability of buses at the time of day you need them.
We are desperately asking for your help in seeing that this law is amended or changed in order to permit the use of these vehicles. I personally don't understand the rationale in allowing a van to transport 10 passengers, but not 11, 12 or 15. Here at Brainerd, we field 12 athletic teams and 2 squads of cheerleaders. We only have 2 revenue producing sports with those being football and basketball. I am hopeful that we will not have to result to cutting out minor sports because of a transportation cost problem. We appreciate your support in this matter. |
|
ID: nht92-6.14OpenDATE: June 8, 1992 FROM: Michael F. Hecker -- Micho Industries TO: Paul Jackson Rice -- Chief Counsel, NHTSA COPYEE: M. Dunn; R. Rogers TITLE: Re: R-BAR Passenger Restraint System ATTACHMT: Attached to letter dated 7/14/92 from Paul J. Rice to Michael F. Hecker (A39; Std. 222) TEXT: I wish to thank you for your response to my letter of March 31, 1992. We understand that the R-BAR, once installed on the seatback, becomes part of the seatback and therefore is subject to the test requirements of F.M.V.S.S. #222. Further, in determining the proper test procedures for this device, in accordance with the stated regulations (CFR 49 571.222 S6.4.) and including Laboratory Procedures #TP-222-01 (re: B. Pretest Procedure, step #6), we understand that since the R-BAR is part of the seatback, and adjustable, that the testing procedures are to be done in its most upright position. Please advise us if this is a proper interpretation of this (S6.4) regulation. Once again, thank you in advance for consideration in this matter. |
|
ID: nht92-6.15OpenDATE: June 5, 1992 FROM: Paul Jackson Rice -- Chief Counsel, NHTSA TO: Robert S. McLean, Esq. -- King & Spalding TITLE: None ATTACHMT: Attached to letter dated 3/9/92 from Robert S. McLean to Paul J. Rice TEXT: This responds to your request for additional information on the requirements applicable to automatic belts. In response to your March 9, 1992 letters, I sent you a March 30, 1992 letter explaining how our requirements apply to automatic belts. Specifically, I explained that an automatic shoulder belt is not a Type 2a belt, as defined in Standard No. 209, and that automatic belts are not required to include any warnings required for Type 2a belts. I noted that all the requirements applicable to automatic belts are set forth in S4.5.3 of Standard No. 208. On May 19, 1992, you sent a FAX to Steve Kratzke of this office asking for a further clarification of the requirements applicable to automatic belts. You followed the FAX up with a telephone call on May 27, 1992, during which you explained that you were seeking an opinion from me with respect to an interpretation that is being asserted in litigation in which you are involved. The issue involves the crash protection requirements in Standard No. 208. S4.1.2 of Standard No. 208 gives vehicle manufacturers a choice of three options for providing occupant crash protection and sets forth specific belt installation requirements for each option. However, S4.5.3 of Standard No. 208 contains an important proviso. This section provides that an automatic seat belt assembly may be used to meet the crash protection requirements of any option set forth in S4.1.2 and in place of any seat belt assembly that would otherwise be required by that option. You explained that another party in your litigation is asserting that an automatic belt, which consists solely of a shoulder belt, could not be used pursuant to S4.5.3 of Standard No. 208 to meet the crash protection requirements of any option in S4.1.2 of Standard No. 208. This is so because, according to this argument, an automatic belt which consists solely of a shoulder belt is not a "seat belt assembly." The reason it is asserted that a shoulder belt alone cannot be a "seat belt assembly" is that S4.1(b) of Standard No. 209 requires that "a seat belt assembly shall provide pelvic restraint." Since an automatic belt that consists solely of a shoulder belt does not provide pelvic restraint, this argument concludes that automatic belts that do not provide pelvic restraint must not be "seat belt assemblies" within the meaning of Standard No. 209. If these belts are not seat belt assemblies, they are not eligible to be used pursuant to S4.5.3 of Standard No. 208 in place of seat belt assemblies otherwise required by Standard No. 208. This argument is without merit. Contrary to the assertion in this argument, automatic belts which consist solely of a shoulder belt are "seat belt assemblies" within the meaning of S3 of Standard No. 209. That section defines a "seat belt assembly" as "any strap, webbing, or similar device designed to secure a person in a motor vehicle in order to mitigate the results of any accident, including all necessary buckles and other fasteners, and all hardware designed for installing such seat belt assembly in a motor vehicle." An automatic belt consisting solely of a shoulder belt falls squarely within this definition. Thus, an automatic belt consisting solely of a shoulder belt may be used pursuant to S4.5.3 of Standard No. 208 to meet the crash protection requirements of the standard and in place of any seat belt assembly that would otherwise be required. It may be that this argument was offered because the person was not aware that automatic belts are not generally subject to the provisions of Standard No. 209 that apply to manual seat belt assemblies, as explained in my March 30, 1992 letter to you. Thus, S4.1(b) of Standard No. 209 does not apply to automatic belts. In place of Standard No. 209's general requirements for manual seat belt assemblies, S4.5.3 of Standard No. 208 sets forth special requirements for automatic belts. No provision of S4.5.3 of Standard No. 208 precludes the use of automatic belts that consist solely of a shoulder belt. I hope this information clarifies any lingering questions you may have had. As before, if you need any further information on the requirements applicable to automatic belts, feel free to contact Steve Kratzke at this address or by telephone at (202) 366-2992. |
|
ID: nht92-6.16OpenDATE: June 5, 1992 FROM: Le Van Lac -- Vice President, Pioneer Electronic Services, Inc. TO: Paul Jackson Rice -- Chief Counsel, NHTSA TITLE: Re: For Legal Interpretation of 108-6, Sec. 5.1.3 ATTACHMT: Attached to letter dated 7/31/92 from Paul J. Rice to Le Van Lac (A39; VSA 108(a)(2)(A)) TEXT: We at Pioneer plan to sell a new car speaker in the U.S. We contacted Mr. Harry Thompson at your office and he advised me to write a letter with explanation to you in order to get your advice. 1. NEW CAR SPEAKER WITH ILLUMINATION: Car speaker will illuminate by a 12 volt DC car battery. this car speaker will be installed in the rear deck of a car. Cosmetically it it well designed with Pioneer brand name to be printed on the rear side of the speaker cabinet. 2. PURPOSE OF ILLUMINATION SPEAKER: By lighting Pioneer brand name with blue color at night (when the head light is switched on), we intend to give a favorable and refined impression to driver, passengers. This illumination car speaker will satisfy the customers who wish to have a high end and unique car speaker. 3. CONSTRUCTION: Light was originated from a lamp. There are 8 lamps for each left and right speaker. The light will go through a filter and then a transparent panel as the drawing. Power consumption of a lamp inside the car speaker using filament type (glass tube) at 1.54 watt. The brightness of this blue light illuminated through the filter and transparent panel is just 1/40 of the high mount stop lamp (measured at 1 meter at 14.4 volt). Therefore, this illuminated speaker will not impair the effectiveness of the existing lighting equipment installed into the car. Attached is the information of this 4-way high-end speaker TS-X450 that has been selling at other countries. Please help to review our request and we hope to receive your approval soon. Thank you very much. Attachment (Text and graphics omitted) |
|
ID: nht92-6.17OpenDATE: June 4, 1992 FROM: Bart Gordon -- U.S. House of Representatives TO: Adele Derby -- Associate Administrator for Regional Operations, NHTSA TITLE: None ATTACHMT: Attached to letter dated 6/29/92 from Frederick H. Grubbe to Bart Gordon (A39; Part 571.3) TEXT: Pursuant to your conversation with Claudia Deane of my Washington staff, I am writing to request a clarification of NHTSA's regulations regarding the use of 11-15 passenger vans for school purposes. In my home state of Tennessee, there is currently some confusion as to whether schools which are in possession of these vans can use them to transport students. The vans are not being used as primary transportation, but instead are used for extracurricular activities such as transporting the debate team or the cheerleading squad. It is my understanding that there are regulation against selling these vans for school use. My question is whether schools which currently own vans can use them. In speaking with state officials, the point of confusion seems to specifically lie in the application of NHTSA's definition of a school bus to these vans, and following on this, whether the vans are required to be in compliance with school bus class safety standards. The state's interpretation of NHTSA's regulations has led them to advise schools to stop using the vans in the 11-15 passenger category. I appreciate your attention to this question and look forward to receiving a response in the near future. If I can answer any questions or provide you with further information, please feel free to contact my office. |
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.