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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 5791 - 5800 of 16514
Interpretations Date
 search results table

ID: aiam5361

Open
Mr. Jim Davis President Russell Performance Products 2645 Gundry Avenue Signal Hill, CA 90806; Mr. Jim Davis President Russell Performance Products 2645 Gundry Avenue Signal Hill
CA 90806;

"Dear Mr. Davis: This responds to your letters to Mr. David Elias formerly of this office, about the requirements of Standard 106, 'Brake Hoses,' for labeling hydraulic brake hose assemblies. I apologize for the delay in responding. You explain in your letters that Russell holds a license to manufacture brake hose assemblies from Titeflex Corporation, a manufacturer of brake hoses, end fittings and assemblies. Titeflex supplies Russell with braided hose, and Russell manufactures the end fittings that Titeflex designed, using Titeflex's engineering drawings. Russell assembles the Titeflex hose with the end fittings, and 'markets these hose assemblies in the marketplace.' You ask about marking the hose assemblies with a designation that identifies the manufacturer of the assembly, pursuant to S5.2.4 of Standard 106. You ask whether both Russell's and Titeflex's designations are required to be labeled, or only the designation of Russell. The answer is only Russell's designation is required to be marked. Russell is manufacturing the assemblies and will market the assemblies. Russell's designation will identify Russell as the manufacturer of the assembly in the event of a possible noncompliance or defect with the assembly. You also ask whether Titeflex's hose must be labeled with the information specified in S5.2.1 and S5.2.2 of Standard 106. The first part of your question asks whether the labeling requirements apply to bulk brake hose 'with a stainless braided outer covering.' The answer is yes. The standard does not exclude braided brake hoses from the labeling requirements. The second part of this question asks about the required labeling for hoses that are part of brake hose assemblies. You ask for confirmation that Standard 106 does not require the hose to be labeled once the hose is part of a brake hose assembly. Your understanding is correct with regard to S5.2.2. The last sentence of that paragraph states: 'The information specified in S5.2.2 need not be present on hose that is sold as part of a brake hose assembly or a motor vehicle.' (The quoted sentence was adopted at 56 FR 50520, October 7, 1991, to replace the sentence you referred to.) Accordingly, the hose need not bear the labeling of S5.2.2 when the hose is part of an assembly. However, the hose must still bear the stripes required by S5.2.1 unless, to quote from S5.2.1, the hose is 'manufactured for use only in an assembly whose end fittings prevent its installation in a twisted orientation in either side of the vehicle.' I hope this information is helpful. If you have any further questions, please contact Deirdre Fujita of my staff at the above address, or by phone at (202) 366-2992. Sincerely, John Womack Acting Chief Counsel cc: Mr. Nicholas S. Copass Sales Manager Titeflex Industrial America 170 Tapley Street Springfield, MA 01104-2893";

ID: aiam4989

Open
Mr. Jeff Ruff Director of Fleet/Government Sales The Braun Corporation 1014 S. Monticello P.O. Box 310 Winamac, IN 46996; Mr. Jeff Ruff Director of Fleet/Government Sales The Braun Corporation 1014 S. Monticello P.O. Box 310 Winamac
IN 46996;

Dear Mr. Ruff: This responds to your letter of February 10, 199 requesting advice regarding the location of the upper anchorage for the front passenger seat shoulder belt. By now, you should have received our reply (dated February 14, 1992) to your previous letter (dated October 30, 1991). In that letter, I explained that NHTSA will not conduct any crash testing of vehicles modified for operation by persons with disabilities while the agency reviews the petition from the Recreation Vehicle Industry Association to exclude these vehicle from the dynamic crash test requirement. Because this is now a pending rulemaking, the agency cannot discuss what requirements the agency will propose for these vehicles prior to the publication of the notice of proposed rulemaking (NPRM). However, as explained in our previous letter, NHTSA is aware of the need of manufacturers such as yourself and your customers to have this matter addressed as soon as possible. Therefore, the agency is proceeding with preparation and publication of the NPRM as quickly as possible. 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: aiam0163

Open
George M. Hilgendorf, Esq., One North La Salle Street, Suite 4100, Chicago, Illinois 60602; George M. Hilgendorf
Esq.
One North La Salle Street
Suite 4100
Chicago
Illinois 60602;

Dear Mr. Hilgendorf: Mr. Frank Coy, Special Assistant to the Under Secretary o Transportation, has asked that I respond to your letter of April 16, 1969, in which you ask whether a station wagon purchased in March of 1968, equipped with two ply tires, violates Federal Motor Vehicle Safety Standard No. 109.; The vehicle you purchased was apparently manufactured prior to April 1 1968, and therefore, it was not required to be equipped with tires conforming to Standard No. 109. However, even if the standard were applicable, because a tire is labeled '2-ply' it is not necessarily a non-conforming tire. Standard No. 109 does not specifically require tires to have a given number of plies. It does require that irrespective of any ply rating tires pass minimum performance tests. As to passenger cars, Standard No. 110 requires that passenger car manufactured after April 1, 1968, (1) must be equipped with tires that comply with Standard No. 109, and (2) the vehicle must not place a load on any of the tires greater than the load capacity of the tire specified in Standard No. 109.; Very truly yours, Howard A. Heffron, Chief Counsel

ID: aiam4823

Open
The Honorable John D. Dingell Chairman, Subcommittee on Oversight and Investigations Committee on Energy and Commerce House of Representatives Washington, DC 20515; The Honorable John D. Dingell Chairman
Subcommittee on Oversight and Investigations Committee on Energy and Commerce House of Representatives Washington
DC 20515;

"Dear Mr. Chairman: Your letter of July 10, 1990 about th applicability of NHTSA's safety standards to replacement parts was misplaced. This is indeed unfortunate, embarrassing, and I can assure you extraordinary. You asked me to review an April 9, 1990 interpretation letter from our Office of Chief Counsel to Mr. Rowghani, which indicated that Standard No. 214, Side Door Strength, applies only to new vehicles, and not to doors sold as replacement parts. In view of your concern about replacement parts, we have reviewed that interpretation, and our authority regarding replacement parts. Many of our safety standards apply only to complete vehicles, while others apply only to the individual components (whether original or replacement equipment). Some apply both to vehicles and to the components involved. Each of our standards includes an 'Application' section, which clearly defines the scope of coverage, based on the nature of the safety issue and the vehicle/equipment items involved. NHTSA's standards which apply to equipment (both original and replacement equipment) generally cover those types of items which can be used in many different vehicle lines, which are frequently replaced or sold separately, and which can be independently tested. These include such items as brake hoses (Standard 106), lamps and reflectors (Standard 108), tires (Standards 109, 117 and 119), windows and windshields (Standard 205), safety belt assemblies (Standard 209), child safety seats (Standard 213), and motorcycle safety helmets (Standard 218). Other safety systems require testing in a full-vehicle context, and our safety standards are applied to the vehicle rather than the component. Examples include brake performance (Standards 105 and 121), occupant crash protection (Standard 208), head restraints (Standard 202) and roof-crush resistance (Standard 216), as well as side-door strength. As noted in the April 9 letter, Standard 214 applies only to whole cars, not to replacement parts, as stated in the application section (see S2 of Standard 214, copy enclosed). While most manufacturers have chosen to meet the Standard by adding reinforcement beams, we are aware of at least one vehicle (a gray-market imported Mercedes-Benz) which passed the standard's compliance test without such a beam. Further, while intuitively it seems that doors without a reinforcement beam are not as safe as ones with a beam, efforts to document a safety problem have been unsuccessful. The current compliance procedures specify testing a door as part of a new vehicle (see S4 of Standard 214), since it does not appear feasible to specify an appropriate procedure for testing an individual new door (whether original or replacement) by itself. The reason for this is that a door's performance in resisting intrusion is dependent not only on the structure of the door itself, but also other factors such as the vehicle frame into which the door fits, and the hinges and latches which hold the door in place within the frame. In addition, vehicle seats may help resist intrusion and protect occupants. The current standard reflects these factors. While the current standard does not apply to replacement doors, NHTSA has full authority to pursue any alleged safety problems with doors or any other vehicle components under the 'defects' provision of the Safety Act. If evidence demonstrated that certain replacement doors presented an unreasonable risk to motor vehicle safety, the agency could order the manufacturer of such doors to repair or replace such doors. At the present time, however, we are not aware of a safety problem with replacement doors that would warrant the commencement of a defects investigation. I appreciate your interest in the safety of vehicle parts and hope this information is helpful. For further discussion of the legal issues regarding the applicability of standards, your staff should feel free to contact our Chief Counsel, Mr. Paul Jackson Rice, at 366-9511. Sincerely, Jerry Ralph Curry Enclosure";

ID: aiam0533

Open
Mr. William C. Bottger, Jr., Latham & Watkins, 615 South Flower Street, Los Angeles, CA 90017; Mr. William C. Bottger
Jr.
Latham & Watkins
615 South Flower Street
Los Angeles
CA 90017;

Dear Mr. Bottger:This is in reply to your letter of November 16, 1971 in which you ask whether a manufacturer may add certain statements to the Certification label required pursuant to Part 567 of Title 49, Code of Federal Regulations. You state that the manufacturer in question is engaged in the manufacture and mounting of concrete mixer assemblies. Because, as you state, the weight of the concrete may vary according to the mix formula, and because the volume of mix loaded into a mixer can also vary, the manufacturer wishes to add to his Certification label a declaration of the vehicle's cargo load and an indication of the maximum volume of mix that could be safely hauled within the rated cargo load limit.; There is no prohibition to this additional information being added t the Certification label as long as (1) it appears after the required information, and (2) it is stated in such a way that it cannot be confused with the information, particularly the GVWR and GAWR, required to be placed on the label.; We are pleased to be of assistance. Sincerely, Richard B. Dyson, Assistant Chief Counsel

ID: aiam1288

Open
Mr. Howard Levine, Ft. Lauderdale Police Dept., 1300 W. Broward Boulevard, Fort Lauderdale, FL (zip code missing); Mr. Howard Levine
Ft. Lauderdale Police Dept.
1300 W. Broward Boulevard
Fort Lauderdale
FL (zip code missing);

Dear Mr. Levine: This is in reply to your inquiry of October 18, 1973, concerning th legal consequences of disconnecting the seat belt interlock systems in the new cars your department is purchasing.; The dealer or distributor from whom you buy the cars is required unde subsection 108(a)(1) of the National Traffic and Motor Vehicle Safety Act, Public Law 89-563 (15 U.S.C. 1397(a)(1)), to deliver them to you with the interlocks operational. However, subsection 108(b)(1) of the act provides that the requirements of subsection 108(a)(1) do not apply after the first purchase of a vehicle for purposes other than resale. As a purchaser who intends to use the cars, rather than resell them, your department is therefore not obliged to keep the interlocks operational.; Yours truly, Richard B. Dyson, Assistant Chief Counsel

ID: aiam4570

Open
J.W. Lawrence, Manager, Compliance Volvo GM Heavy Truck Corporation 7825 National Service Road Airpark West, P.O. Box 26115 Greensboro, NC 27402-6115; J.W. Lawrence
Manager
Compliance Volvo GM Heavy Truck Corporation 7825 National Service Road Airpark West
P.O. Box 26115 Greensboro
NC 27402-6115;

"Dear Mr. Lawrence: This is a response to your letter of October 5 1988, asking this agency to 'reconsider and rescind' an interpretation of Standard 124, Accelerator Control Systems (49 CFR /571.124). The interpretation which was the subject of your request was addressed to Mr. Leon Steenbock and dated March 17, 1988. Mr. Steenbock asked whether it is permissible under Standard 124 to install a locking hand throttle control in a new motor vehicle. In our response to Mr. Steenbock, we stated that while nothing in the Standard prohibits installing a hand-throttle control in a new vehicle, ''locking hand throttle controls' are expressly prohibited by Standard 124.' In your letter, you stated that most (and perhaps all) heavy truck manufacturers install hand throttles for engine warm-up, extended idle periods, and for vocational applications such as pumping, compacting, and mixing. You also stated that your company installs only locking hand throttle controls and that these locking hand throttle controls hold the driver-selected engine idle speed until such time as the driver selects a new idle speed, or disengages the throttle. In support of your position that the letter to Mr. Steenbock was incorrect, you referred to the agency's response to petitions for reconsideration of Standard 124. NHTSA's response to requests that special provisions be made for hand throttles was as follows: Mack and Alfa Romeo petitioned that 'hand-throttles' and throttle positioners be specifically excluded from the definition of 'idle position.' Petitioners stated that in the event such a device is used a return to the preset throttle position occurs upon release of the driver-operated accelerator control system. This request is granted. If a driver choose to raise the lowest engine speed threshold by the use of a throttle positioning device, the throttle should return to that new position within the same time requirements specified in section S5.3. Accordingly, the NHTSA is amending the definition of 'idle position' to provide for the use of throttle positioners. (37 FR 20033, September 23, 1972.) In accordance with this stated intent, the definition of 'idle position' in S4.1 of Standard 124 was amended to read: (T)he position of the throttle that will provide the lowest engine speed for existing conditions according to the manufacturers' recommendations. These conditions include, but are not limited to, engine speed adjustments for cold engine, air conditioning equipment, and emission control equipment, and the use of throttle setting devices. Because of this language, we agree with your position that Standard 124 permits the installation of hand throttles, including locking hand throttle controls, provided that the vehicle's engine returns to the lowest engine speed threshold as adjusted by use of the hand throttle within the time and under the conditions set forth in S5 of Standard 124. To the extent that our March 17, 1988 letter is inconsistent with this interpretation, it is incorrect. I hope you find this information helpful. If you have further questions, please call Joan F. Tilghman of my staff at (202) 366-2992. Sincerely, Erika Z. Jones Chief Counsel cc: Mr. Leon Steenbock Administrative Manager, Engineering FWD Corporation Clintonville, WI 54929-1590";

ID: aiam0860

Open
Mr. Satoshi Nishibori, Engineering Representative, Nissan Motor Co., Ltd., 560 Sylvan Avenue, Englewood Cliffs, NJ, 07632; Mr. Satoshi Nishibori
Engineering Representative
Nissan Motor Co.
Ltd.
560 Sylvan Avenue
Englewood Cliffs
NJ
07632;

Dear Mr. Nishibori: This is in reply to your letters of August 8, and August 28, 1972 requesting interpretation of Motor Vehicle Safety Standard No. 302, 'Flammability of Interior Materials'.; In your August 8th letter, as we understand your first question, yo ask whether the adhesive, sound-proofing material used on the floor panels of your cars should be tested together with the few insulating fibers which become embedded in this material when the insulation which covers the sound- proofing material is removed. The Standard provides a list of the interior components which must meet its requirements and the manner in which those components are to be tested. Since the sound-proofing material you have described would not be considered a floor covering and it is not otherwise included in S4.1 of the Standard, it is not subject to the requirements.; You ask further whether the 'seal screen' you glue peripherally on th inner, door panels to prevent water from penetrating the interior of the door must meet the requirements of the Standard. The 'seal screen', as you describe it, does not appear to be part of the panel and, accordingly, it would not be subject to the Standard.; In your August 28th letter, you ask whether the procedure you have fo testing the 'jute' insulating material used under the floor carpet of your cars conforms to the requirements of Standard No. 302. You state that this procedure includes removing the insulation and testing its top surface, which you designate as 'surface B', rather than testing its bottom surface, which you designate as 'surface A'. We are not sure what you mean by testing a 'surface', the Standard refers to a test for the entire specimen. You may be concerned with whether the specimen is oriented upward or downward. Under the Standard, the test specimen for each component is to be tested 'so as to provide the most adverse results'. Accordingly, the relevant test result is the most adverse one achieved in any horizontal orientation, either upward- or downward-facing. The fact that you remove the insulating material so as not to raise the nap on its bottom surface is consistent with existing test procedures.; Yours truly, Richard B. Dyson, Assistant Chief Counsel

ID: aiam1772

Open
Ms. Dianne Black, Liaison Engineer, British Leyland Motors Inc., 600 Willow Tree Road, Leonia, NJ 07605; Ms. Dianne Black
Liaison Engineer
British Leyland Motors Inc.
600 Willow Tree Road
Leonia
NJ 07605;

Dear Ms. Black: This is in response to your letter of December 19, 1974, requestin interpretations of two test conditions contained in Standard No. 301-75, *Fuel System Integrity*.; Your first question relates to the static rollover test condition an asks whether it was the NHTSA's intention that the vehicle be rotated to three positions only for spillage measurement. (Paragraph S7.4 specifically refers only to increments of 90 degrees, 180 degrees, and 270 degrees.) The static rollover test is intended to test the amount of fuel spillage a vehicle experiences at each 90 degree increment in a full 360 degree rotation. The standard presumes that the test begin with the vehicle in an upright position. It is from this upright position that the vehicle begins its movement to the remaining three 90 degree increments.; Your second question asks for an interpretation of the section relatin to the operation of the vehicle's fuel pump during testing. Paragraph S7.1.3 of the standard requires that a electrically driven fuel pump be in operation during the barrier crash tests if it normally operates with the activation of the vehicle's electrical system. If pump operation requires the operation of the vehicle's engine, ten (sic) the pump should not be running during the barrier crash tests. If the fuel pump installed in your barrier is capable of independent operation as described in SF.1.3 it should be operating during the barrier crash tests even if it cuts off fuel at the moment of impact. Under the existing requirements, whether a pump out of fuel at impact would not be relevant to whether it must be operating at impact. Of course, over cutoff feature would be considered as pard of the bump's normal operation.; Yours truly, Richard B. Dyson, Acting Chief Counsel

ID: aiam4120

Open
Mr. Sidney K. Saksenberg, Manager of Regulatory Affairs, CSA Limited, Inc., P.O. Box 690347, Houston, TX 77269-0347; Mr. Sidney K. Saksenberg
Manager of Regulatory Affairs
CSA Limited
Inc.
P.O. Box 690347
Houston
TX 77269-0347;

Dear Mr. Saksenberg: This responds to your November 12, 1985 letter to NHTSA's Office o Vehicle Safety Compliance, concerning the packaging requirements of Federal Motor Vehicle Safety Standard No. 116, *Brake Fluid*, You asked whether the brake fluid container you enclosed would comply with the standard. Your letter has been referred to my office for reply.; By way of background information, I must explain that NHTSA does no pass approval on the compliance of any vehicle or equipment with a safety standard before the actual events that underlie certification. Under the National Traffic and Motor Vehicle Safety Act, it is your responsibility as a manufacturer to determine whether your products comply with all applicable safety standards and regulations, and to certify your products in accordance with that determination. Therefore, the following interpretation only represents the agency's opinion based on your letter and enclosure.; The sample container you enclosed is plastic and has a resealable scre cap. The cap is attached to a plastic band, or ring, encircling the opening of the container, and the attachment is broken when the cap is twisted open. The cap itself is lined with an inner seal which you have indicated is impervious to the packaged brake fluid.; Standard No. 116 specifies performance and labeling requirements fo motor vehicle brake fluids and their containers. Paragraph S5.2.1 of the standard sets forth specific requirements for container sealing of brake fluid packages:; >>>Each brake fluid or hydraulic system mineral oil container with capacity of 6 fluid ounces or more shall be provided with a resealable closure that has an inner seal impervious to the packaged brake fluid. The container closure shall include a tamper-proof feature that will either be destroyed or substantially altered when the container closure is initially opened.<<<; The container you enclosed appears to be provided with a resealabl closure, i.e., the twist-off cap, and an impervious inner seal. The cap's tamper-proof feature is the attachment to the plastic ring that would be broken (and thus 'destroyed or substantially altered') when the cap is initially opened. Although not required by the standard. you have taken the commendable extra step of including a statement on the cap that warns purchasers not to accept the container if the seal is broken. We would suggest that you ensure that the warning is clearly legible.; Sincerely, Erika Z. Jones, Chief Counsel

Request an Interpretation

You may email your request to Interpretations.NHTSA@dot.gov or send your request in hard copy to:

The Chief Counsel
National Highway Traffic Safety Administration, W41-326
U.S. Department of Transportation
1200 New Jersey Avenue SE
Washington, DC 20590

If you want to talk to someone at NHTSA about what a request for interpretation should include, call the Office of the Chief Counsel at 202-366-2992.

Please note that NHTSA’s response will be made available in this online database, and that the incoming interpretation request may also be made publicly available.