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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 10361 - 10370 of 16490
Interpretations Date

ID: nht71-3.6

Open

DATE: 05/21/71

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Louisiana Independent Tire Dealers Association

TITLE: FMVSS INTERPRETATION

TEXT: The "Flash Notice" that you forwarded to us on April 23, 1971, and your telephone conversation of May 10 with Mike Peskoe of my staff have raised certain questions concerning your interpretation of Motor Vehicle Safety Standard No. 117, "Retreaded Pneumatic Tires."

On page 1 of the "Flash Notice" you state, "But, so far as testing goes, it's apparent the risk for retreaders not to do their own testing to prove compliance is substantially greater than anticipated." You proceed to discuss whether manufacturers should test their own tires in order to prove "due care." As part of this discussion you refer to the statement in the preamble in the Notice of March 5, 1970, concerning what could suffice for a valid certification, and state that we have told you that this preamble is "still basically valid."

There is evidently some confusion as to the purpose and meaning of "due care" under the National Traffic and Motor Vehicle Safety Act, and also as to the difference between compliance and certification.

A manufacturer of a retreaded tire that did not comply with the standard but who used due care in manufacturing the tire to comply with the standard cannot be subject to a civil penalty. The answer to your hypothetical question on page 3, "What if due care is used, but the tire doesn't comply" is that the manufacturer cannot be subject to a civil penalty in this situation. (He may, however, be required to send defect notification letters and be urged to recall.) We do not agree that one is "guilty until proven innocent." A finding of noncompliance must first be made by the agency. Once the agency, through testing or otherwise, discovers a noncompliance, it is then up to the manufacturer to show that he exercised due care. Although the issue of due care is one that is ultimately decided by a court, the agency, in determining whether to seek a civil penalty, will make a preliminary determination on this issue.

You asked in your conversation of May 10 that we amplify what is meant by "due care." "Due care" is a legal concept embodying the care that would be exercised by a reasonable man under the circumstances, and the circumstances of each situation must be considered in determining whether due care has been exercised. The set of cirumstances set forth in the preamble of March 5, 1970, might constitute "due care" in a large number of situations. To be sure, a manufacturer who tests his own tires might be considered in some cases to have exercised more care to insure that his tires complied with the standard than one who relied on tests by a third person on other tires that were similarly manufactured. Each potential case would be considered, and decided, by the agency on the facts peculiar to it.

The "Flash Notice" also mentions "certification" in such a way that clarification of the term is indicated. First, all tires manufactured after the standard's effective date must be certified. Certification is accomplished, as you know, by placing the symbol "DOT" on the tire in a prescribed location.

In practice, all tires will have the symbol "DOT" affixed to them after January 1, 1972, as manufacturers could not manufacture these tires without placing the mark on them. The answer to your question on page 3, "What if one certified does not comply" is that even if the tire fails to comply, if the manufacturer has exercised due care, in the view of the court, in manufacturing the tires to comply to the standard, his certification will not be considered "false or misleading," and no civil penalty can be imposed. The same "due care" that will suffice for compliance will suffice for purposes of certification. Manufacturers' efforts should be directed to manufacturing tires that conform to the standard.

Your "Flash Notice" also incorrectly explains certain provisions of the standard. First, with reference to which tests a particular tire must pass, S5.1.1 requires each tire to be able to pass every test, but when a single tire, during the agency testing, is subjected to one of the groups of tests specified in S5.1.1, that particular tire will not be tested further. As indicated to you on the phone, this is similar to the test procedure of Standard No. 109. It merely reflects that fact that certain tests, such as strength, normally destroy the tire.

Your statement on page 4 concerning the labeling requirements, that retreaders can "buff off the labeling required in retreading without worry, since it is displayed in other areas," is unclear to us. The standard requires each item of information required by Standard No. 109 to be retained in at least one location (Standard No. 109 requires each item to be on both sidewalls) on the complete retreaded tire. Retreaders must therefore take care that each tire retains the original marking to this extent.

Finally, with reference to the physical dimension requirements of S5.1.2, the 10 percent tolerance refers only to the maximum dimension with respect to the section width specified in the tables of Standard No. 109. Your reference on page 4 to "10% under" is incorrect, since no minimum measurement is stated in the standard. However, the section width is a variable in computing the size factor which must be at least the minimum specified for the tire in the tables in the Appendix.

If you have further questions, please let us know.

ID: nht80-3.31

Open

DATE: 08/05/80

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Department of Public Instruction - North Dakota

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your July 3, 1980, letter asking whether a ramp device used in school buses for the transportation of the handicapped would be in conflict with the Federal safety standard for school bus emergency exits if the ramp partially blocked the rear exit when it folded into the bus. You indicate in your letter that the ramp would make the exit release mechanism difficult to operate for small children. Although your letter provides few details concerning the ramp, we conclude that it probably would render the vehicle in noncompliance with the emergency exit regulation.

Standard No. 217, Bus Window Retention and Release, regulates the number and size of school bus emergency exits and requires that the release mechanisms of those exits be readily accessible. The purpose of these requirements, of course, is to provide an easily operable, unobstructed school bus emergency exit. In the past, we have preempted a State requirement for a safety chain that would have been placed across an exit, because we viewed the chain as providing an obstruction to the opening. Similarly, it appears to us that the ramp you describe would provide an impediment to emergency vehicle exits and would not permit easy access to the release mechanism. Accordingly, we conclude that a bus with such a ramp as original equipment would not comply with the Federal safety standards. We note further that the ramp could not be added as aftermarket equipment by any manufacturer, dealer, or repair business, without rendering inoperative the compliance of the bus with the safety standard. Nothing, however, precludes a school from adding the ramps to its own vehicles except the possibility of increased liability in the event a child is injured in an accident involving the bus.

There are many possible devices designed to aid the transportation of the handicapped that would not conflict with the standards. For example, many vehicles have lifts designed for handicapped use. It might also be possible to have a ramp at the rear door that stows under the vehicle when not in use rather than in the passenger compartment. Any of these alternatives would be better than a ramp that might block the emergency exit.

SINCERELY,

THE STATE OF NORTH DAKOTA

Department of Public Instruction

July 3, 1980

Roger Tilton Office of Chief Counsel National Highway Traffic Safety Administration

Dear Mr. Tilton: A bus used to transport handicapped people has a ramp device at the rear door of the bus. The ramp is bolted to the floor of the bus and folds to be brought inside the bus for travel. The ramp remains in front of the door when the door is closed. The door latch can be reached so the door could be opened from the inside and the ramp pushed out for use as an emergency exit, although this would be fairly difficult for a very young child.

We have been asked if a device of this type would be in conflict with the Safety Standard for emergency exits for school buses.

Can any type of device be located inside the emergency door as original equipment on a school bus based on the Safety Standard for emergency exits?

Thank you for your help.

ROLLAND LARSON, Director

Pupil Transportation

(Graphics omitted)

ID: 7437

Open

Mr. M. K. Chaudhari
Director ARAI
The Automotive Research Association of India
Survey No. 102
Vetal Hill
Off Paud Road, Kothrud
Pune-411 004 India

Dear Mr. Chaudhari:

This responds to your letter requesting the testing procedure for and test results of vehicles equipped with anti-skid brake systems. These systems are also referred to as anti-lock brake systems. You also requested the addresses of equipment manufacturers that produce anti-lock brake systems. I am pleased to have this opportunity to provide you information about this topic.

By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not provide approvals of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act ("Safety Act"), it is the responsibility of the manufacturer to ensure that its vehicles or equipment comply with applicable standards issued by this agency. A manufacturer then certifies that its vehicles or equipment comply with the applicable standards. I am enclosing a copy of an information sheet entitled, "Information for New Manufacturers of Motor Vehicles and Motor Vehicle Equipment," which explains a manufacturer's responsibility under NHTSA's regulation.

I am also enclosing a copy of the two safety standards issued by NHTSA that apply to brake systems: Standard No. 105, Hydraulic Brake Systems (49 CFR 571.105) and Standard No. 121, Air Brake Systems (49 CFR 571.121). These standards are intended to insure the safe braking performance of vehicles under normal and emergency conditions. Vehicle manufacturers are required to certify that vehicles they manufacture comply with these performance-oriented standards. Nothing in these standards currently specifies that vehicles be equipped with an anti- lock device. For your information, the agency is considering proposing additional requirements that might require medium and heavy duty vehicles to be equipped with anti-lock brake systems. A copy of that notice is enclosed (57 FR 24212, June 8, 1992). In addition, the agency has issued a supplemental notice of proposed rulemaking in which the agency is considering whether to harmonize its passenger car brake standard with international standards. (56 FR 30528, July 3, 1991). A copy of that notice is also enclosed.

With respect to your request for test results related to anti-lock brake performance, I am enclosing the agency's most recent report on this topic. It is entitled "Improved Brake Systems for Commercial Motor Vehicles."

With respect to your inquiry requesting the addresses of equipment manufacturers, the agency is unable to provide such information. The following associations may be able to help you obtain this information:

Motor Vehicle Manufacturers Association 7430 Second Avenue, Suite 300, Detroit, MI 48202 (Telephone No. 313-872-4311, Fax No. 313-872-5400)

Brake System Parts Manufacturers Council 300 Sylvan Avenue P.O. Box 1638 Englewood Cliffs, N.J. 07632-0638 (Tel. No. 201-569-8500, Fax No. 569-0159)

I hope this information is helpful. If you have any further questions about NHTSA's safety standards, please feel free to contact Marvin Shaw of my staff at this address or by telephone at (202) 366-2992. The fax number is (202) 366- 3820.

Sincerely,

Paul Jackson Rice Chief Counsel

Enclosures

Ref:105#121 d:8/12/92

1992

ID: nht74-1.14

Open

DATE: 07/03/74

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Imperial-Eastman Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your May 2, 1974, questions concerning the labeling of multi-piece end fittings, the use of hose marked with the DOT symbol in non-brake applications, and the acceptability of an end fitting design under the requirements of Standard No. 106, Brake hoses.

The answers to your first two questions will appear in the upcoming notice responding to petitions for reconsideration of amendments to Standard No. 106.

As to the acceptability of a certain end fitting design, the standard specifies performance requirements for end fittings. Any design which meets the specifications of the standard may be manufactured after the effective date of the standard.

Yours truly,

May 2, 1974

Docket Room National Highway Traffic Safety Administration

Ref: FMVSS106, Docket 1-5, Note 10

Gentlemen:

Imperial-Eastman Corporation, a manufacturer of brake hose, couplings, and hose assemblies have a direct interest in FMVSS106, and hereby submit the following comments or requests for interpretations; they are not items for petition.

1. S7.2 Labeling

"Except for two-piece end fittings that are attached by deformation of the fitting about a hose by crimping or swaging, each air brake hose end fitting shall be permanently etched, embossed or stamped, in block capital letters and numerals at least one-sixteenth of an inch high with the DOT labeling information."

We assume that on three-piece air brake hose end fittings which utilize sacrificial sleeves or ferrules, and are considered permanently attached end fittings, that it would be permissible to mark only the coupling nut, with the DOT labeling information.

2. Thermoplastic air brake hose in accordance with SAE J844, Type 3 is currently being used by practically most major truck manufacturers in the United States on original equipment. This hose is normally used to replace copper tubing and/or rubber hose in air brake systems.

This type of thermoplastic hose with air brake hose end fittings is also used for auxiliary lines to windshield wipers, air horns, pressure gages, etc., and for fuel lines.

Fittings and/or fitting components used in these applications may be identical with those used in and marked for air brake applications. Is it permissible for these items to retain the DOT labeling information when used in these other applications?

3. The SAE has a committee which has proposed a fitting performance specification for SAE J844, Type 3, Nylon air brake tubing. One of the types of fittings that meet this performance specification and is currently being used by most major truck manufacturers on air brake systems, consist of a nut, sleeve, tube support and body. The tube support is a brass eyelet, pressed into the body by the coupling manufacturer, which prevents collapse of the tubing. The body is a standard air brake body which meets SAE J246 Standard. For service replacement a loose eyelet and sleeve are provided.

Such fittings are neither described within the DOT Standard, nor specifically excluded from it. Assuming that such fittings are qualified to the DOT test requirements of the standard, and are marked in accordance with the standard, may we then assume they are acceptable?

Sincerely,

IMPERIAL-EASTMAN CORPORATION Imperial Division

Robert C. Gibson Standards and Specifications Engineer

ID: 11522ZTV

Open

Mr. Michael Yu
Design Engineer
Gillig Corporation
Box 3008
Hayward, CA94540-3008

Dear Mr. Yu:

This responds to your letters of February 1 and 12, 1996, asking for interpretations of Motor Vehicle Safety Standard No. 108 with respect to the rear lighting configuration depicted on a drawing that you enclosed with each letter.

In your letter of February 1, you are concerned with the four lamps designated "1", "2", "3", and "4". They are all amber, and activated when the brake pedal is applied. Lamps 1 and 2 flash alternatively with lamps 3 and 4. The lamps are extinguished when the brakes are released.

The drawing you enclosed show that these are not lamps that are required by Standard No. 108, but supplemental lighting equipment. Paragraph S5.5.10 of Standard No. 108 specifies the required lamps that may flash in use, and S5.5.10(d) clarifies that "all other lamps shall be steady burning." This means that supplemental lighting equipment added by the manufacturer or dealer before a vehicle's first sale must be steady burning. I would also like to call your attention to paragraph S5.1.3 of Standard No. 108; supplemental lighting equipment is permissible if it does not impair the effectiveness of lighting equipment required by the standard. Even if paragraph S5.5.10 permitted supplemental lighting equipment to flash, we believe that your system would impair the effectiveness of the stop lamps. The four lamps are activated simultaneously with the stop lamps, but are of a different color and flash in use. When confronted with an array of red steady burning lamps and amber flashing ones, there is a strong likelihood of at least momentary confusion in a driver following the bus.

In your letter of February 12, your drawing shows two amber lamps mounted approximately at the upper right and left corners of the vehicle. They, too, flash when the brake pedalis depressed. This appears to be a variation of the four-lamp system discussed above, and for the same reasons we consider this system also to be prohibited by S5.5.10(d).

This also responds to Gillig's telephone call of February 13 to Taylor Vinson in which it asked for NHTSA's views on systems of flashing red lamps instead of amber ones. Additional red lamps that are activated simultaneously with the stop lamps appear to serve as a supplemental stop lamp system. However, under S5.5.10(d), they, too, must be steady burning. If Gillig wishes to configure the systems described in this letter to be both red and steady burning, we would not view such a configuration as creating an impairment of the effectiveness of other rear lighting equipment within the meaning of paragraph S5.1.3.

If you have further questions, you may refer them to Taylor Vinson of this Office (phone: 202-366-5263).

Sincerely,

Samuel J. Dubbin Chief Counsel ref:108 d:3/34/96

1970

ID: nht79-3.50

Open

DATE: 07/06/79

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Wayne Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your June 11, 1979, letter asking whether side push-out window exits in school buses installed pursuant to State requirements must be marked in accordance with the emergency exit requirements of S5.5.3 of Standard No. 217, Bus Window Retention and Release. In particular, you want to know whether these additional exits must be labeled on the bus exterior.

Section S5.5.3 of the standard requires that "[each] school bus emergency exit provided in accordance with S5.2.3.1 shall have the designation . . . . on both the inside and outside surfaces of the bus. Section S5.2.3.1, in turn, requires that school buses be equipped with a rear emergency door or a side emergency door and a rear push-out window. Taken together, these two sections require that the required rear or side emergency door or rear push-out window must be appropriately marked on the inside and outside of the bus.

As the agency has frequently stated, all exists installed in school buses beyond those required by S5.2.3.1 need not comply with the exit requirements applicable to school bus exits. All additional exists must comply, however, with the other sections of the standard applicable to non-school buses. In this case, the additional exits would be required to be labeled in accordance with Sections S5.5.1 and S5.5.2 of the standard. Neither of these paragraphs requires the exit to be marked on the bus exterior.

SINCERELY,

Wayne Corporation

June 11, 1979

Frank Berndt Chief Counsel U.S. Department of Transportation % National Highway Traffic Safety Administration

Dear Mr. Berndt:

The State of New York Department of Transportation has raised a question concerning the exterior labeling of side push-out windows in school buses. Specifically, they maintain that Section S5.5.3 of FMVSS 217 requires that side emergency push-out windows specified in the New York school bus standard be labeled on the outside of the bus as specified in this section. Wayne maintains that only the rear emergency door, side emergency doors, and rear push-out windows are required to be labeled on the exterior in accordance with the requirements of S5.5.3.

Please advise which of these interpretations is correct. Would you please send a copy of your reply to Mr. Martin Chauvin at the following address.

Mr. Martin V. Chauvin, Chief Carrier Safety Bureau New York State Department of Transportation 1220 Washington Avenue State Campus Albany, New York 12232

Robert B. Kurre Director of Engineering

CC: MARTIN CHAUVIN

ID: 86-2.49

Open

TYPE: INTERPRETATION-NHTSA

DATE: 04/28/86

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: Robert P. Horbatt

TITLE: FMVSS INTERPRETATION

TEXT:

Mr. Robert P. Horbatt President Semperit Tire Company 156 Ludlow Avenue Northvale, NJ 07647

Dear Mr. Horbatt:

This responds to your letter to Stephen Kratzke of my staff, in which you stated your interpretation of the requirements of the Uniform Tire Quality Grading Standards (49 CFR S575.104: "UTQGS"). You stated that your company is introducing a new all-season tire to the United States market, and that you would like to import the first six months' production without the UTQGS grades molded onto the sidewall of the tires, but with paper labels showing those grades. This course of action is expressly permitted by the UTQGS.

First, the UTQGS is applicable to all-season tires. Section 575.104(c)(1) specifies that the UTQGS does not apply to "winter-type snow tires." The National Highway Traffic Safety Administration has explained that winter-type snow tires refers only to tires with a deep tread rubber and tread design which are inadvisable for year-round use on passenger automobiles. Since all-season tires are not "winter-type snow tires," they are subject to the requirements of the UTQGS. See 44 FR 30139, at 30140: May 24, 1979.

The requirement that the grades assigned under the UTQGS be permanently molded onto one sidewall of each passenger car tire is set forth in 49 CFR S575.104(d)(1)(i)(A). However, that section reads: "Except for a tire of a new tire line, manufactured within the first six months of production of the tire line, each tire shall be graded with the words, letters, symbols, and figures ... permanently molded into or onto the tire sidewall...." A tire line introduced for the first time into the United States is considered a new tire line for the purposes of this section. Therefore, our UTQGS regulation does not require you to mold the assigned grades onto a sidewall of those tires manufactured within the first six months of production. Such tires are subject to the requirement that a paper label, showing the UTQGS grades assigned to the tire, be affixed to its tread surface (49 CFR S575.104(d)(1)(i)(B)), and that the grades assigned to those tires appear in the information furnished to prospective purchasers of the tires (49 CFR S575.6 (c)).

If you have any further questions or need more information of this subject, please contact Mr. Kratzke at this address or by telephone at (202) 426-2992.

Sincerely,

Original Signed By

Erika Z. Jones Chief Counsel

February 27, 1986

Mr. Steven Kratske Office of Chief Council NHTSA Room 5219 400 Seventh Street S.W. Washington, D. C. 20590

Dear Mr. Kratske:

Semperit Reifen A.G. in Austria, our parent company, would like to introduce a new All Season Tire to the United States market.

In accordance with the DOT regulations, we would like to import the initial first six months' production without engraving the UTQG ratings in the sidewall but with a label listing UTQG ratings.

In the meantime, we are in the process of permanently engraving the UTQG ratings in the molds to comply with the regulations.

Yours truly,

SEMPERIT TIRE COMPANY

Robert P. Horbatt President

RPH:ms

ID: 06-007052rls

Open

Mr. John Coursen

Product Line Manager

Structural Composites Industries

325 Enterprise Place

Pomona, CA 91768

Dear Mr. Coursen:

This responds to your email in which you seek confirmation of the proper bonfire test procedure when two or more compressed natural gas (CNG) fuel containers are connected to a common manifold under Federal Motor Vehicle Safety Standard No. 304, Compressed Natural Gas Fuel Container Integrity (Standard No. 304). Specifically, you ask if it would be proper to perform bonfire testing as specified under paragraph S8.3 with the entire group of interconnected containers and their shared pressure relief devices (PRDs) being tested, as opposed to testing containers individually. Based on the information you have provided, we would not conduct the Standard No. 304 test in the manner you describe, because the standard specifies that in the bonfire test, NHTSA tests CNG fuel containers individually. However, this does not prevent you from performing additional testing of your interconnected CNG fuel containers as a group if you wish to do so.

By way of background, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue Federal motor vehicle safety standards (FMVSSs) that set performance requirements for new motor vehicles and items of motor vehicle equipment (see 49 U.S.C. Chapter 301). NHTSA does not provide approvals of motor vehicles or motor vehicle equipment. Instead, manufacturers are required to self-certify that their products conform to all applicable safety standards that are in effect on the date of manufacture. NHTSA selects a sampling of new vehicles and equipment each year to determine their compliance with applicable FMVSSs. If our testing or examination reveals an apparent noncompliance, we may require the manufacturer to remedy the noncompliance, and may initiate an enforcement proceeding if necessary to ensure that the manufacturer takes appropriate action.

In your letter, you describe a system of CNG containers in which two or more fuel containers are interconnected by a manifold, with multiple PRDs attached to the manifold for venting the fuel containers as a group. You state that two CNG containers, with a common manifold with two PRDs, would be the expected configuration.

Standard No. 304 is an equipment standard, which specifies requirements for the integrity of [CNG] motor vehicle fuel containers (Standard No. 304, S1).[1] Standard No. 304 regulates CNG fuel containers individually with their PRDs: note, for example, that every use of the term CNG fuel container in the standard is singular, not plural. Regarding the bonfire test in particular, both S7.3 and S8.3 refer to the CNG fuel container, not to containers or to fuel container systems. This is reflected in our enforcement offices laboratory test procedure for Standard No. 304, which tests each CNG fuel container individually, and states that each shall be equipped with a pressure relief device or integral thermal protection system.[2]

Even though Standard No. 304 does not require multiple interconnected fuel containers to be tested as a group, you may perform such a test yourself. The FMVSSs provide a minimum threshold of safety, as established by performance and testing requirements. However, you are free to perform additional testing of your products in order to ensure that they do not pose an unreasonable risk of safety when used on the road.

If you have any further questions, please do not hesitate to contact Rebecca Schade of my staff at (202) 366-2992.

Sincerely yours,

Anthony M. Cooke

Chief Counsel

ref:304

d.3/29/07




[1] Note that multiple linked containers would be evaluated as a system under Standard No. 303, Fuel system integrity of compressed natural gas vehicles. Standard No. 303 is a vehicle standard, as opposed to an equipment standard like Standard No. 304. Standard No. 303 specifies fuel leakage limits for the vehicle when subjected to crash tests. The responsibility to meet Standard No. 303 is borne by the vehicle manufacturer in cases in which your system is installed on a new vehicle by or with the express authorization of that vehicle manufacturer. 

[2] NHTSAs Laboratory Test Procedure for FMVSS 304, Compressed Natural Gas (CNG) Fuel Container Integrity (TP-304-03, Dec. 8, 2003) is available at http://www.nhtsa.dot.gov/staticfiles/DOT/NHTSA/Vehicle%20Safety/Test%20Procedures/Associated%20Files/TP304-03.pdf. The quotes above are taken from page 13 of that document

2007

ID: 2837o

Open

Mr. Robert W. Hocken
General Manager
Phoenix Transit System
P.O. Box 4275
Phoenix, AZ 85030

Dear Mr. Hocken:

This is in reply to your letter of December l6, l987 to Mr. Vinson of this office requesting an interpretation of Motor Vehicle Safety Standard No. l08. You have received a "Service Information Safety Related letter" from Flxible Corporation stating that deceleration warning lights installed on your buses do not comply with Standard No. l08. You have also asked how you may file for "Special Exception" if your buses are not in compliance.

This will confirm that Flxible Corporation, pursuant to applicable Federal regulations, has determined that certain buses produced by it, including the 67 units furnished Phoenix, do not comply with Standard No. l08, and has initiated a notification and remedy campaign (Campaign 87V-089). The basis of this determination was the manufacturer's conclusion that flashing amber deceleration warning lamps could create confusion when activated simultaneously with the red steady burning stop lamps. The company has advised you of the corrective action to be taken, that is, to remove the deceleration flasher. Although the agency encourages owners of campaigned vehicles to remedy noncompliances, the decision whether to do so rests with the vehicle owner. There is no Federal requirement that an owner correct a noncompliance that exists in his vehicle, and no penalty for his failure to do so. Thus, no "Special Exception" is either needed or available for an owner who wishes to continue operating a vehicle in a noncompliant state.

We are interested in your comment that you experienced a 44 percent reduction in accidents in l985, the first full year that the system was installed on all your buses, compared with l984. This report compares favorably with the accident reduction experienced in our test fleets of passenger cars equipped with center highmounted stop lamps, which was the basis for eventual adoption of that requirement. The agency is engaged in research pertaining to the conspicuity of large vehicles, and would find it helpful to have a copy of the data upon which you based your comment. It should be sent to Michael Finkelstein, Associate Administrator for Research and Development, NHTSA, 400 Seventh Street, S.W., Washington, D.C. 20590. We appreciate your interest in safety.

Sincerely,

Erika Z. Jones Chief Counsel

ref:l08#VSA d:3/7/88

1988

ID: nht94-3.94

Open

TYPE: INTERPRETATION-NHTSA

DATE: August 9, 1994

FROM: Barry Felrice -- Associate Administrator for Rulemaking, NHTSA

TO: Gerald Plante -- Manager, Product Compliance, Saab Cars USA, Inc.

TITLE: NONE

ATTACHMT: Attached to letter dated 4/25/94 from Gerald Plante to Barbara Gray

TEXT: Dear Mr. Plante:

This responds to your request that the National Highway Traffic Safety Administration (NHTSA) determine that a proposed modification to a previously approved antitheft device on the Saab 900 car line is a de minimis change to the device. The proposed mo dification is to be placed on the Saab 900 line beginning with the 1995 model year. As explained below, the agency concludes that the proposed changes to the antitheft device are not de minimis.

As you are aware, in a Federal Register notice of July 26, 1993 (58 FR 39853), NHTSA determined that the antitheft device, to be placed as standard equipment on the MY 1994 Saab 900 line, was likely to be as effective as parts marking.

For the following reason, NHTSA concludes that the proposed changes to the antitheft device for the 1995 model year are not de minimis. In reaching this conclusion, we looked primarily at the antitheft device on which the exemption was originally based. For the MY 1994 device, locking the driver's door with the ignition key automatically locks all doors, arms the alarm system and activates the starter interrupt-relay. For the MY 1995 device, Saab plans to add a remote control device. The remote contr ol is separate from the ignition key that locks/unlocks the driver's door. Locking the driver's door with the remote locks all other doors, arms the alarm, and activates the starter interrupt-relay. While locking the driver's door with the ignition key will lock all other doors as before, it will no longer arm the alarm system or activate the starter interrupt-relay.

This is not an insignificant change like the substitution of new components for old components, each serving the same function. Further, the change does not simply involve adding a feature making the original device even more effective. With the existin g device, a single means (the ignition key) for locking the driver's door locked all other doors, armed

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the alarm and activated the interrupt-relay. With the planned new device, the remote does not supplant the ignition key as the means for locking the driver's door; it supplements the key. Thus, there will be less certainty with the new device that lock ing the driver's door will arm the alarm and activate the interrupt-relay.

Accordingly, NHTSA concludes that Saab's proposed modification to the antitheft device in the MY 1995 Saab 900 car line is not a de minimis change.

If Saab wishes to place its proposed antitheft device on the 900 car line for MY 1995, it must file a petition with NHTSA pursuant to 49 CFR @ 543.9(c)(2). Please note that the petition for modification must provide the same information for the modified device as is required under @ 543.6 for a new device. This includes the statement in @ 543.6(a)(1) that the antitheft device will be installed as standard equipment on all vehicles in the line for which an exemption is sought.

If you have any questions, please contact Barbara Gray or Rosalind Proctor at (202) 366-1740.

Request an Interpretation

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

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

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

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

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