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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.”

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NHTSA's Interpretation Files Search



Displaying 8431 - 8440 of 16503
Interpretations Date
 

ID: 1982-1.9

Open

TYPE: INTERPRETATION-NHTSA

DATE: 02/03/82

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Rolls-Royce Motors Ltd.

TITLE: FMVSS INTERPRETATION

TEXT:

NOA-30 February 3, 1982

Mr. B. G. Ridgway Chief Car Safety and Regulations Engineer Rolls-Royce Motors Ltd. Car Division Crew, Cheshire CW1 3PL England

Dear Mr. Ridgway:

This responds to your letter concerning the labeling requirements of Standard No. 105 applicable to a separate indicator lamp concerning reservoir level. Your letter asked whether it is permissible to use words other than "Brake Fluid" for vehicles which use hydraulic system mineral oil rather than conventional brake fluid. As explained below, the answer is yes.

Section S5.3.5 of Standard No. 105 states in relevant part:

...If separate indicator lamps are used for one or more of the various functions described in S5.3.1(a) to SS.3.1(d), the lens shall include the word "Brake" and appropriate additional labeling (use "Brake Pressure," "Brake Fluid" for S5.3.1(a) and S5.3.1(b)) except that if a separate parking indicator lamp is provided, the single word "Park" may be used....

As your letter pointed out, conventional brake fluid and hydraulic system mineral oil are not compatible. Safety Standard No. 116, Motor Vehicle Brake Fluids, differentiates between "brake fluid" and "hydraulic system mineral oil."

We interpret section S5.3.5 to require the use of the words "Brake Fluid" only for vehicles which use conventional brake fluid. The section's use of the word "appropriate," prior to its statement that "Brake Fluid" be used for S5.3.1(b), indicates that the labeling set forth in the parentheses need only be used where it adequately describes the fluid being used. For vehicles which use hydraulic system mineral oil, or other types of non-conventional brake fluid which might be developed in the future, the general requirement for the word "Brake" and appropriate additional labeling is applicable.

We are concerned, however, about your proposed use of the words BRAKE HSMO/LHM, since we doubt that many persons would understand that HSMO/LHM is an abbreviation for hydraulic system mineral oil/liquide hydraulique minerale. We suggest that you consider using the words "BRAKE MINERAL OIL" or similar language that more persons would understand.

Sincerely,

Frank Berndt Chief Counsel

cc: Mr. Kenneth W. Preece Regulations and Special Projects Manager Rolls-Royce Motors, Inc.

Box 476 Lyndhurst, NJ 07071

The Administrator BGR DT National Highway Traffic Safety Administration 400, Seventh Street S.W. WASHINGTON D.C. U.S.A. 7th April, 1981

Possible PART 552 PETITION FOR RULEMAKING FEDERAL MOTOR VEHICLE SAFETY STANDARDS FMVSS 707-80 - CONTROLS AND DISPLAYS FMVSS 705-75 -HYDRAULIC BRAKE SYSTEMS

Dear Administrator,

Rolls-Royce Motors Limited believes that the requirements of these two standards, if strictly applied to the letter of the rules, force us into providing cars which have safety systems less safe than they would be with a less strict interpretation of the rules.

Rolls-Royce Motors Limited no longer uses BRAKE FLUID, as defined in FMVSS 776 in cars supplied to the USA market. HYDRAULIC SYSTEM MINERAL OIL (HSMO), again as defined and controlled by FMVSS 116, is used instead.

The braking systems provided in the cars have a comprehensive system of warning displays, separate displays being provided for the two pressure systems and a further display to warn if the level of the HYDRAULIC SYSTEM MINERAL OIL in either of the two separate reservoirs is too low.

FMVSS 101-80 controls the wording for this reservoir level warning display by its reference to FMVSS 105-75 in Table 2.

The specified wording in FMVSS 105-75 paragraph 5.3.5, for reservoir level, 5.3.7(b) is "Brake Fluid". We note that this wording is within parentheses and believe that it is intended to be advisory and we hope that you will accept our use of a different, safer, wording.

We are most concerned that the appearance of the words BRAKE FLUID would immediately bring to the minds of the driver and service personnel the thought of adding conventional brake fluid to the reservoir. This must not happen. As you know, and FMVSS 116 recognises, Brake Fluid and Hydraulic System Mineral Oil are NOT COMPATIBLE.

We have taken every care to label the reservoirs and the car, we have provided full customer and service information to avoid any risk of Brake Fluid being wrongly put into the reservoirs. If we can use different wording on the reservoir level warning display we can complete our safety information system without any ambiguity.

We therefore intend to use the following wording on the reservoir level warning display:-

BRAKE

HSMO/LHM

Where HSMO and LhM are abbreviations for Hydraulic system mineral oil and Liquide Hydraulique Minerale respectively. LHM will suit our Cars sent to Canada and it is a well known trade mark for HSMO.

In the interests of enhancing the safety of our products we intend to implement this change of wording at the earliest time.

We would appreciate your confirmation that our action will not be taken as non-compliance with either FMVSS 101-80 or FMVSS 105-75. Should you be unable to give this confirmation we hereby PETITION you to change FMVSS 105-75 paragraph S.5.3.5 so that it permits us to label our products in a manner which we feel is more safe.

Yours faithfully,

B. G. Ridgway Chief Car Safety and Regulations Engineer

ID: 1982-2.1

Open

DATE: APRIL 6, 1982

FROM: J. F. WALKUP -- PROJECT ANALYST-REEVES BROTHERS, INC.

TO: ROGER TILTON -- CHIEF COUNSEL-NHTSA

TITLE: NONE

ATTACHMT: ATTACHED TO APRIL 30, 1982 LETTER FROM BERNDT TO WALKUP

TEXT: Reeves Bros. is interested in determining if there are fire retardancy regulations covering replacement automobile seat covers.

Our understanding, from sources within the National Highway Traffic Safety Administration, is that there are no regulations covering the after market.

If this information is correct, would you please advise Reeves in writing?

Thank you for your assistance.

ID: 1982-2.10

Open

DATE: 04/30/82 EST

FROM: FRANK BERNDT -- NHTSA CHIEF COUNSEL

TO: J. F. WALKUP -- PROJECT ANALYST, RESEARCH & DEVELOPMENT CENTER-REEVES BROTHERS, INC.

TITLE: NONE

ATTACHMT: APRIL 6, 1982 LETTER FROM WALKUP TO TILTON IS ATTACHED

TEXT: This responds to your April 6, 1982, letter asking whether the agency's Standard No. 302, Flammability of Interior Materials, applies to after-market equipment. The answer to your question is no.

Standard No. 302 is a vehicle standard and as such applies to completed vehicles. No vehicle can be manufactured unless the materials used in it comply with the requirements of the standard. The standard does not apply, however, to items of equipment in the after market. You should be aware that while you would not be prohibited from manufacturing after-market equipment that does not comply with the standard, a manufacturer, repair business or dealer would be prohibited from installing such noncomplying equipment if the installation would have the effect of rendering inoperative the compliance of the vehicle with the safety standard. Nothing prevents a vehicle owner, however, from installing noncomplying equipment in his own vehicle.

I trust that this responds to your question. Please contact me if I can be of further assistance.

ID: 1982-2.11

Open

DATE: 05/04/82

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Name not released

TITLE: FMVSR INTERPRETATION

TEXT: This is in reply to your letter of March 23, 1982, asking for a "confidential interpretation" of the applicability of certain Federal motor vehicle safety standards to sidecars.

The agency does not provide "confidential interpretations." Your questions are of public interest and a copy of this letter will be placed in the interpretations file that is available for public review. However, because it relates to "specific future model product plans," we are deleting your name and address from the copy of our response made available to the public.

You first ask for confirmation of your understanding that no Federal motor vehicle safety standard is applicable to a sidecar "sold independently as an aftermarket item." It is true that there are no "sidecar" standards. But certain of its equipment items are themselves covered by Federal equipment standards and must independently comply. Specifically, brake hoses, lighting equipment, tires and glazing (if provided) would have to meet Standards Nos. 106, 108, 119, and 205 as they apply to motorcycle equipment. In addition, because a sidecar is an item of motor vehicle equipment, the manufacturer of any sidecar sold in the aftermarket would be responsible for notification and remedy in the event his product was determined to contain a safety-related defect.

You have presented the hypothetical situation of a motorcycle supplied to a retail dealership with the sidecar attached by the manufacturer and asked whether it is considered to be a three-wheeled motorcycle or a two-wheeled motorcycle with an attachment of motor vehicle equipment. You point out that the former interpretation raises questions of practicability of compliance with the standards.

The definition of a motorcycle encompasses both two- and three-wheeled vehicles, and we believe that the questions you have raised subsequently with respect to Standards Nos. 108, 119, 120, and 122 should be answered on a common sense basis. For lighting equipment on the front and rear of a motorcycle the vertical center line of a motorcycle with sidecar attached is the vertical center line of the two-wheeled motorcycle. However, the side reflex reflector should be placed on both the motorcycle and the sidecar. Standards Nos. 119 and 120 must be met by the motorcycle with the sidecar attached. In addition, a motorcycle whose original equipment includes a sidecar must meet Standard No. 122 with the sidecar attached. If a motorcycle with sidecar is capable of meeting Standard No. 122 without the sidecar being equipped with a brake, then the sidecar need not have a brake.

I hope this answers your questions.

ID: 1982-2.12

Open

DATE: May 10, 1982

FROM: Frank Berndt -- Chief Counsel, NHTSA; Signature by Stephen P. Wood

TO: Martin V. Chauvin -- Chief, Carrier Safety Bureau, Department of Transportation

TITLE: None

ATTACHMT: Attached to letter dated 3-27-78 from J.J. Levin, Jr. to B. Nanninga (VSA 102(14)); Also attached to letter dated 8-3-77 from J.J. Levin, Jr. to J.L. O'Connell (VSA 102(14)); Also attached to letter dated 7-12-77 from J.J. Levin, Jr. to J. Thomason (VSA 102(14)); Also attached to letter dated 9-10-90 from P.J. Rice to E. Kultgen (A36; VSA 108(b)(1); VSA 102(14); Part 571.3); Also attached to letter dated 5-29-90 from E. Kultgen to S.P. Wood (OCC 4843)

TEXT:

This responds to your April 9, 1982, letter asking whether vehicles used to transport children to or from day care centers and summer camps must comply with the school bus safety standards.

The agency has determined that vehicles used to transport children to day care centers need not comply with the school bus safety standards. This determination is based on the fact that facilities which are essentially custodial, even though they may have some educational components, are not considered to be schools.

With respect to summer camps, if the camps are associated with a school, the use of school buses would be required. On the other hand, camps with no school affiliation need not use school buses to transport their children. For the legislative history on the subject of camps, see the enclosed excerpt from House debates, 120 Cong. Rec. H8123 (daily ed. Aug. 12, 1974).

The agency has not developed a list of those facilities that are required to use school buses. As a general guideline, any operation associated with a school must, of course, use school buses. A head start facility is required to use school buses, since it is considered to be a preprimary school. Other facilities whose functions are primarily educational must also use school buses, since they are considered schools. As noted above, facilities that are essentially custodial need not use school buses.

I hope these guidelines will be useful to you.

ID: 1982-2.13

Open

DATE: 05/19/82

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Transequip Industries Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your recent letter asking whether Federal regulations allow a brake hose to be used as a dual purpose hose for both the service brakes and the emergency brake.

Standard No. 121, Air Brake Systems, does not preclude the use of common components in parking, emergency, and service air brake systems. Accordingly, nothing would prevent you from using a common hose in those systems. However, the common component would have to comply with the requirements for each system. This means that a failure of the hose would always be treated as a failure in the parking, emergency and service brake systems. Applying this to the standard in section S5.2.1.1, it would be necessary for the parking brakes to be capable of being released with a failure of the common hose at any time. If your system cannot perform in this manner, which it appears it cannot, it could not comply with the safety standard.

Our engineering staff has reviewed your brake system very carefully over the past years. It appears that your system can be properly plumbed in a manner that it would seem to comply with the requirements. You have continued to seek slightly less expensive methods to plumb your system. In our opinion, these methods would not be capable of complying with the standard. We cannot see how your system can comply with the standard without traditional plumbing that is being used by many brake manufacturers today. Accordingly, we suggest that you concentrate your efforts on constructing your system in that manner.

SINCERELY,

transquip industries, inc.

March 22, 1982

Chief Counsel, NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION

Sir:

In an air actuated, mechanically held system for trailers, such as described in the enclosed drawing, a single diaphragm brake chamber is provided using one delivery hose per chamber.

The brake hose (#25 on the drawing) is used as a dual purpose hose; It is used as a service brake hose when the service brakes are applied, and it becomes an emergency brake hose when the emergency brakes are applied. The destinction is in the application.

Should the hose break or puncture while applying the service brakes, three of the brakes would apply while air from the broken hose would go to atomosphere.

With the use of two 1400 cu in air tanks and the supply line continuously refilling the tanks, it is virtually impossible to cause a mechanical lock-up while using service brakes.

Should the trailer be parked with the emergency brakes applied and then cut the brake hose the air tanks would drain to zero. When the driver pushed in the tractor protection valve the broken hose would be sealed off, the tanks would refill and the parking brakes would then release when air pressure reached about sixty PSI. The failure which caused the lock-up could only occur when the trailer is in emergency.

My question is as follows: "Can a hose be used as a dual purpose hose and be considered a service brake hose while applying the service brakes and as an emergency brake hose while applying the emergency brakes"? Please advise.

Edward H. Clapp, President

(Graphics omitted)

NOTES:

1. DASHED ITEMS (Illegible) ARE NOT INCLUDED IN KIT.

2. FOR USE WITH DISC BRAKES, CONTACT FACTORY.

3. LENGTH TO BE DETERMINED BY CUSTOMER.

(Graphics omitted)

TRANSQUIP INDUSTRIES, INC.

614 West Main Street

Memphis, Texas 79245

TITLE TWO TANK - SINGLE VALVE SYSTEM TANDEM AXLE (2800 C.I.)

ID: 1982-2.14

Open

DATE: 05/27/82

FROM: FRANK BERNDT -- CHIEF COUNSEL, NHTSA; SIGNATURE BY STEPHEN P. WOOD

TO: Mrs. James J. Mitchell Jr.

TITLE: FMVSS INTERPRETATION

TEXT: The National Highway Traffic Safety Administration is pleased to learn that you want to install a high-mounted stop lamp on your 1978 Buick LaSabre. The two studies that the Administration funded, one with the Essex Corporation and the other with the Allen Corporation, indicated that rear end collisions could possibly be reduced by 50 percent with the use of a single high-mounted stop lamp. We do not know whether the States of New York or New Jersey will allow the use of these lamps. Our Office of Rulemaking contacted the American Association of Motor Vehicle Manufacturers (AAMVA) but the information we received was indefinite, and I would suggest that you contact your local State Police for a definitive answer. The agency has proposed that passenger cars be equipped with this system, and if the proposal is adopted, the lamps would be legal in all States.

As to where to locate these lamps on the car, our research showed that a single lamp, placed on the rear vertical centerline of the vehicle and within the back window (either inside or outside) was the most effective position. Our research also included a system of two high-mounted lamps, mounted on either side of the rear window, apparently similar to the one you observed in upstate New York; however, this was not nearly as effective as the single lamp system in reducing rear end collisions.

SINCERELY,

April 2, 1982

Department of Transportation National Highway Safety Administration

Gentlemen:

Based on the attached article, which appeared in the June 1981 issue of McCall's Magazine, I sent a check for $ 29.90 to Amerace Brands Division, Hilite, Ace Road, Butler, N.J. 07405 for two Slimsonite Hi Lite brake lights, to fit a 1978 Buick LaSabre sedan.

Would you please tell me which states authorize these lights and where they must be placed on the car -- I am, of course, interested in New York State. The reason I make this inquiry is that when my husband took the lights to our local service station, the mechanic suggested that my husband check with the local police regarding the legality of these lights. We border on the State of New Jersey. My husband learned that we could not affix the lights; that if we did, he would be asked to remove them by the police.

When we traveled upstate New York, I noticed a car with similar lights, affixed in the back window, on either side. I must say that they do indicate when the car ahead is stopping. As a legal secretary, I worked on many accident cases, and I personally feel that a driver should give all the warning he can when he plans to stop.

Thank you for your reply.

Mrs. James J. Mitchell, Jr.

ID: 1982-2.15

Open

DATE: 06/14/82

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Carrier Transicold Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of May 18, 1982, "regarding the legality of placing a red alternator warning light on the side of a truck refrigeration unit."

Because the warning light is not required as original motor vehicle lighting equipment under Federal Motor Vehicle Safety Standard No. 108, it is subject only to the prohibition of paragraph S4.1.3 that it not impair the effectiveness of lighting equipment which the standard requires. The required lighting equipment on the sides of trucks are side marker lamps and reflectors, amber to the front as far as practicable and red to the rear as far as practicable. If the truck's overall length is 30 feet or greater, intermediate lamps and reflectors, amber in color, must be added at or near the mid-point between the front and rear markers.

You have not stated where the warning light will be located, nor the length of the truck on which it would be mounted. To avoid any suggestions of conflict we recommend, if the lamp is to be mounted on a truck carrying intermediate side markers, that it be as close to the rear as practicable. On a short truck equipped with only front and rear side marking devices any location from the mid-point rearward would be acceptable. These locations should also satisfy any questions State authorities may have.

SINCERELY,

May 18, 1982

United States Department of Transportation

Attention: Legal Counsel FMVSS108

Gentlemen:

I am writing you regarding the legality of placing a red alternator warning light on the side of a truck refrigeration unit. The proposed warning light would be a continuous (non-blinking) incandescent lamp, 0.64 inch in diameter. This light would function similar to alternator warning lights found on automobile dashboards, illuminating only when the alternator is failing to charge the battery.

My questions then are:

1. Is red a legally acceptable color for such a light?

2. If red is an unacceptable color, what other colors might also be restricted.

If you require any additional information in answering these questions, please contact me on (315) 432-6168 or leave a message with my secretary on (315) 432-6094.

Thank you for your cooperation.

David R. Siegenthaler Truck/Trailer Engineering

ID: 1982-2.16

Open

DATE: 06/23/82

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Grebe; Gross; Jensen & Peek; P.C. -- J. Mack Shively

TITLE: FMVSS INTERPRETATION

TEXT: Grebe, Gross, Jensen & Peek, P.C. 1530 S.W. Taylor Street Portland, Oregon 97205

This is in response to your letter of May 11, requesting our views as to the applicability of vehicle identification number requirements and certification label requirements to a semi-trailer to be manufactured by Cranston Diversified Industries. This trailer would have three interchangeable sections.

You are correct in your interpretation of the manner in which our requirements would be applied to the trailers in question. Only one vehicle identification number and one certification label are required. Affixing the label to the left side of the front section would be consistent with our regulations.

Sincerely,

Frank Berndt Chief Counsel

Office of Chief Counsel

RE: Manufacturer Identification Cranston Diversified Industries, Inc.

Dear Sirs:

My client, Cranston Diversified Industries, Inc., is currently negotiating with the patent holder to construct a semi-trailer which can be converted from a "flat" to a "drop center" trailer configuration. The design utilizes interchangeable front, rear, and center sections.

I have concluded that pursuant to 49 C.F.R ampersand 571.155, Standard No. 115, S4.1, each vehicle manufactured requires only one vehicle identification number. I have also concluded that the label to be attached to each trailer should be affixed to the left side of the front section (the hitch structure) and that only one label is required pursuant to 49 C.F.R. ampersand 567.4(d).

Please advise me as to whether my interpretation of your Regulations is correct. I have enclosed a copy of the Letters Patent of the United States issued for the trailer which include a detailed description of its structure.

Thank you very much for your attention to this matter.

Sincerely,

J. Mack Shively JMS:vs Enclosures cc: Cranston Diversified Industries, Inc.

ID: 1982-2.17

Open

DATE: 06/30/82

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Mr. Jeff Wimer

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your phone request of June 11, 1982, concerning Federal motor vehicle safety standards that apply to motorcycle sidecars sold as aftermarket motor vehicle equipment.

While there are no "sidecar" standards, certain of the items of equipment that may be found in sidecars are covered by Federal equipment safety standards. Specifically, brake hoses, lighting equipment, tires, rims, and glazing materials (if provided) would have to comply with Standards Nos. 106, 108, 119, 120 and 205. I have enclosed an information sheet explaining how you can obtain copies of the agency's safety standards.

Because a sidecar itself is an item of motor vehicle equipment, the manufacturer of any sidecar sold in the aftermarket would be responsible for notification and remedy in the event the product was determined to contain a safety-related defect.

If you have any further questions, please let me know.

ENC.

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.