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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 841 - 850 of 16505
Interpretations Date
 

ID: 7145

Open

Mr. Tm Kozy
Marketing Director
InfiniMed
2105 S. Hardy Dr., Ste. 5
Tempe, AZ 85282-1990

Dear Mr. Kozy:

This responds to your March 24, 1992 letter concerning "adaptive aids (hand controls) in cars equipped with air bags." I am pleased to have this opportunity to explain our regulations to you. Your two questions and the response to each follows.

1. Is it illegal to install a hand control unit that is drilled into the steering column that, according to the bulletin issued by Chrysler Corporation referring to the Federal Motor Vehicle Safety Standard 208, voids the warranty on the air bag as it may render the system inoperative.

To the extent you are seeking information about warranty claims, NHTSA has no authority to regulate those issues. Therefore, I cannot comment on the effect installation of hand controls might have on a warranty. The only Federal agency that has authority to regulate questions relating to warranties in general is the Federal Trade Commission. If you wish to contact that agency for further information regarding warranty questions, you may write to: Mr. Barry J. Cutler, Director, Bureau of Consumer Protection, Federal Trade Commission, Pennsylvania Avenue at Sixth Street, N.W., Washington, D.C. 20580.

I will, however, discuss the implications of the laws and regulations administered by this agency on the installation of hand controls in motor vehicles. Section 103 of the National Traffic and Motor Vehicle Safety Act (the Safety Act; 15 U.S.C. 1392) authorizes NHTSA to issue Federal Motor Vehicle Safety Standards that set performance requirements for new motor vehicles and new items of motor vehicle equipment. Manufacturers are required to certify that their products meet all applicable safety standards. NHTSA periodically tests certified products to ensure that they do, in fact, comply with applicable standards, and investigates allegations that products contain defects related to motor vehicle safety.

If a new vehicle were altered by installation of adaptive controls prior to the vehicle's first sale to a consumer, the person making the installation would be considered an "alterer" and would be required by 49 CFR Part 567, Certification, to certify that the vehicle continues to comply with all applicable safety standards affected by the alteration. With respect to the installation of adaptive controls at a driver's position equipped with an air bag, the party making such an installation would be obliged to certify that the air bag is capable of functioning at least as well with the adaptive control installed as it functioned before the installation.

After the first sale to a consumer, a vehicle is no longer required by Federal law to conform to all safety standards, and persons modifying the vehicle are no longer required to attach certification labels. However, 108(a)(2)(A) of the Safety Act provides as follows:

No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard...

This provision obliges any manufacturer, dealer, distributor, or repair business that installs adaptive controls in vehicles equipped with air bags at the driver's position to ensure that such installation does not "render inoperative," or interfere with, the protection afforded the driver by the air bag. Violations of this "render inoperative" prohibition in the Safety Act are punishable by civil fines of up to $1,000 per violation. I note that 108(a)(2)(A) does not affect modifications made by vehicle owners to their own vehicles.

Finally, under the Safety Act, adaptive controls would be considered items of motor vehicle equipment. There are currently no Federal motor vehicle safety standards that apply to adaptive controls as a separate item of motor vehicle equipment. However, although no safety standards apply directly to adaptive controls as a separate item of motor vehicle equipment, manufacturers of adaptive controls are subject to the requirements in 151-159 of the Safety Act concerning the recall and remedy of products with safety defects. In the event that NHTSA or a manufacturer determines that a manufacturer's product contains a safety- related defect, the manufacturer is responsible for notifying purchasers of the defective equipment and remedying the problem free of charge.

2. I need to know if such a unit were installed on an air bag equipped vehicle, and that same vehicle is resold in, say a year or two, is the seller required by law to notify the next buyer that the warranty on the air bag system has been voided, even though the controls may now have been removed.

At the outset, I must again note that this agency has no authority over warranty issues or alleged unfair trade practices. Any such questions should be addressed to the Federal Trade Commission at the address given above. My answer is limited to obligations imposed by the Safety Act and the standards and regulations issued by this agency pursuant to that Act.

The "render inoperative" provision of the Safety Act does not impose an affirmative duty on dealers to replace equipment that was previously removed by someone else, or to repair equipment that was damaged in a crash. Thus, the "render inoperative" provision does not require a dealer to replace an air bag that does not function because of something that happened before the dealer took possession of the vehicle, including the installation of hand controls. Moreover, nothing in the Safety Act imposes a duty on dealers of used vehicles to disclose information to purchasers. Notwithstanding the absence of any such requirements in the Safety Act, a dealer may be required by State law to repair or replace the air bag in these circumstances. For further information on the provisions in various State laws, you may contact: the American Association of Motor Vehicle Administrators, 4600 Wilson Boulevard, Arlington, Virginia 22203.

I hope you find this information helpful. If you have further questions or need some additional information in this area, please contact Mary Versailles of my staff at this address or by telephone at (202) 366-2992.

Sincerely,

Paul Jackson Rice Chief Counsel

ref:VSA#208 d:5/5/92

1992

ID: 7169-3

Open

Mr. Charles Chun
General Manager
Kia Motors Corporation
Los Angeles Office
1 Technology Drive, Building H
Irvine, CA 92718

Dear Mr. Chun:

This responds to your letter of April 1, 1992, requesting an interpretation of section S5 of Federal Motor Vehicle Safety Standard No. 214, Side Impact Protection. You asked two questions, which I have answered below.

First, you asked about the meaning of "manufactured date," in connection with cars that would be produced at your factory in Korea and imported into the United States. Specifically, you asked whether the "manufactured date" would be the date of production at the Kia factory or the date of U.S. customs clearance.

For purposes of S5 of Standard No. 214 and all the rest of the Federal motor vehicle safety standards, the date of manufacture is the date on which the assembly and other manufacturing operations are completed for a motor vehicle. See 49 CFR Part 571.7 and 49 CFR Part 567.4(g)(2) and (5). Therefore, the "manufactured date" for the your company's vehicles would be the production date at the Kia factory in Korea.

Second, you asked whether "manufactured date," as used in S5 of Standard No. 214, has the same meaning as "model year." The answer is no. The term "model year" is defined in 49 CFR Part 565.3(h) as "the year used to designate a discrete vehicle model irrespective of the calendar year in which the vehicle was actually produced, so long as the actual period is less than two calendar years." As explained above, the concept of "manufactured date" refers to the actual date on which manufacturing operations are completed on a vehicle, not a year designation chosen by the manufacturer.

Please note that the minimum percentage phase-in requirements for Standard No. 214's dynamic requirements are based on annual production periods and not model years. See, for example, S8.1 to S8.1.1 of Standard No. 214. A manufacturer's annual production of passenger cars manufactured on or after September 1, 1993 and before September 1, 1994 would include all passenger cars completed during that time. The annual production period for purposes of the Standard No. 214 phase-in would not be based on the number of passenger cars which the manufacturer chose to designate as model year 1994 cars.

I hope the above information is responsive to your inquiry. Should you have any further questions or need any additional information regarding this matter, please feel free to contact Mr. Walter Myers of my staff at this address or by telephone at (202) 366-2992.

Sincerely,

Paul Jackson Rice Chief Counsel

ref:214#571#567 d:5/22/92

1992

ID: 7170

Open

Mr. Tom Mario
Vice President Sales
Sealco Air Controls, Inc.
215 East Watkins Street
Phoenix, AZ 85004

Dear Mr. Mario:

This letter responds to your inquiry about recent amendments to Federal Motor Vehicle Safety Standard No. 121, Air Brake Systems, with respect to trailers. That final rule (56 FR 50666, October 8, 1991, copy enclosed) amended the standard by deleting the requirement for a separate reservoir capable of releasing the parking brake. It also added requirements for the retention of a minimum level of pressure in a trailer's supply line in the event of pneumatic failure and for the prevention of automatic application of trailer parking brakes while the minimum supply line pressure is maintained. I am pleased to have this opportunity to explain our requirements.

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, the manufacturer is responsible for certifying that its vehicles or equipment comply with applicable standards.

NHTSA promulgates safety standards that specify performance requirements for motor vehicles and motor vehicle equipment.

One such safety standard, Standard No. 121, specifies performance requirements for braking systems on vehicles equipped with air brake systems, including most trailers. Any air brake system that complies with the performance requirements set forth in Standard No. 121 would be permissible.

You first asked whether a trailer could be equipped with a protected separate reservoir after the amendment becomes effective on October 8, 1992. The answer is yes. While the amendment deletes a provision requiring a protected service reservoir, nothing in the amendment would prohibit a trailer from being equipped with this device. Your next two questions asked which air brake system would be required on certain axles for different types of trailers. As indicated above, any air brake system that complies with the performance requirements set forth in Standard No. 121 would be permissible. I note that while the standard does include certain specific requirements for braking at particular axles, all of the requirements amended or adopted in the October 1991 final rule are written in terms of overall vehicle braking performance. Therefore, in order to ensure compliance with these requirements, manufacturers must assess how the selection of brake designs at each axle will affect overall braking performance.

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. Sincerely,

Paul Jackson Rice Chief Counsel Enclosure

ref:121 d:5/21/92

1992

ID: 7171

Open

Mr. Michael Love
Manager, Compliance
Porsche Cars North America, Inc.
P.O. Box 30911
Reno, Nevada 89520-3911

Dear Mr. Love:

This responds to your letter of April 3, 1992, requesting concurrence by this Office in your interpretation of the requirements of Standard No. 108 for the location of center highmounted stop lamps.

Porsche wishes to install a center lamp on the movable spoiler of its 911 Carrera, a configuration previously approved by this Office providing that all photometric and visibility requirements are met. However, S5.3.1.8 of Standard No. 108 requires that "If the lamp is mounted below the rear window, no portion of the lens shall be lower than 6 inches below the rear window on convertibles, or 3 inches on other passenger cars." Although Porsche's intended center lamp meets this requirement with the spoiler in the extended position (when the car reaches 45 to 55 mph and slows to 9 to 12 mph), at other times, when the spoiler is lowered, the center lamp would be 7.5 inches below the window on the coupe, and 9.5 inches for the convertible.

Nevertheless, you believe that this may be acceptable. You cite an opinion rendered Mazda in which NHTSA did not object to center lamps mounted on tailgates because, as we advised Mazda, the center lamp is a "supplementary" lamp, and that "Even if the deck, hatch, or tailgate upon which it is mounted should be open, following drivers may still observe the signals of the primary stop lamps. . ." You further quote NHTSA's frequently repeated advisory that "Compliance of a vehicle is determined with respect to its normal driving position. . . ," and argue that Porsche's design "fulfills the spirit of the height requirements under all conditions" and the height requirement itself "under a majority of 'normal driving conditions.'" You further argue that even in the down position the triangular relationship between the center lamp and the stop lamps is retained. Finally, you argue that the proposed lamp conforms with NHTSA's philosophy to make Standard No. 108 more performance-oriented "by fulfilling the photometric requirements at all positions."

I am sorry that we cannot concur in your interpretation. When we judge whether a vehicle meets the location and visibility requirements of Standard No. 108, we determine compliance of the vehicle in what appears to us to be its normal operating or driving position. The fact that the vehicle may not comply under all conditions of operation is, of course, of concern to us, but we try to weigh the realities of vehicle design and usage against the need of the public for safety. In the Mazda interpretation, there was no question that the vehicle as manufactured would comply with the locational requirement for center lamps when the tailgate was closed. The "normal driving position" of a vehicle with a tailgate is with the tailgate in the closed position, and use of a vehicle with the tailgate not closed is likely to be infrequent compared with its use with the tailgate closed. In another interpretation, rendered years ago, the fact that a vehicle with hydraulic suspension would not meet the minimum height requirements for headlamps with the vehicle at rest was considered a technical noncompliance only because by the time the vehicle was in its normal operating condition (with the engine running and the car ready to move into the stream of traffic), the suspension had raised the vehicle to a height where the headlamps exceeded the minimum height requirements.

By contrast, the center lamp on the Carerra will not meet the locational requirements from a state of rest up to a minimum of 45 mph, that is to say, under low-speed urban driving conditions where the center lamp is most likely to achieve its purpose of reducing the frequency and severity of rear end impacts. This, to us, is the "normal operating position" of the Carerra with respect to the location of the proposed center lamp.

I would like to close by pointing out that the agency went to a considerable extent in considering the comments of manufacturers before adopting the requirements of S5.3.1.8, in order to minimize design restrictions consistent with safety. NHTSA proposed three alternative locations, and adopted one that was less restrictive than any of the alternatives. Subsequently, pursuant to petitions for reconsideration by vehicle manufacturers, NHTSA relaxed the location requirements of S5.3.1.8 even further.

Sincerely,

Paul Jackson Rice Chief Counsel ref:108 d:4/27/92

1992

ID: 7174

Open

Mr. Michael F. Hecker
Micho Industries
P.O. Box 1791
Goleta, CA 93116

Dear Mr. Hecker:

This responds to your letter of April 2, 1992 concerning possible interpretations of section S5.1.4(c) of Federal Motor Vehicle Safety Standard No. 222, School bus passenger seating and crash protection, as it applies to the R-BARR Passenger Restraint System (R-BAR). (While your letter refers to section S5.1.2(c), you clarified in a telephone conversation with Mary Versailles of my staff that your concerns relate to section S5.1.4(c).) The R-BAR is a padded restraining device, and the ends of the device attach to the rear of a school bus seatback. The device folds down for the purpose of restraining the passengers seated in the next rearward seat. Your letter states that Micho Industries believes that:

A. The standard is not applicable to the R-BAR passenger restraint.

B. The R-BAR complies with the intent of Standard No. 222.

To support these statements you offer the following reasons:

1. The R-BAR is not a fixed position device, nor is it a rigid component of the seat structure.

2. In the event of a rear impact, the R-BAR incorporates a design that allows it to move upward, and away, from the adjoining seat which would thus allow the minimum clearance as intended.

3. The standard in question (571.222, section S5.1.4(c)) was written without the authors having the benefit of knowledge of this type of device and thus allowances were not included for its possible use.

The issue of whether Standard No. 222 is applicable to a device such as the R-BAR has been addressed previously by this agency. Enclosed are copies of four letters concerning similar devices (Mr. Joseph F. Mikoll, November 3, 1988, and March 10, 1989; The Honorable Robert J. Lagomarsino, January 8, 1990; and Mr. Scott K. Hiler, January 31, 1991). Those letters make it clear that if a device such as the R-BAR is installed in any new school bus, the school bus manufacturer must certify that the vehicle meets all applicable safety standards with the device installed. The letters also make it clear that such devices may not legally be installed in used school buses by commercial establishments such as repair businesses if the effect of such installation is to take the vehicle out of compliance with any safety standard.

With respect to your assertion that the R-BAR complies with the intent of Standard No. 222, the National Traffic and Motor Vehicle Safety Act requires NHTSA to issue Federal motor vehicle safety standards that prescribe objective requirements. Under the Act, manufacturers must certify that their products comply with the requirements of all applicable standards and not merely with some alleged "intent" of a standard. Further, manufacturers may not certify products based on speculation that the agency would have established different requirements had it known of a particular design.

With regard to your specific concerns about S5.1.4(c), that section states that when a seat back is subjected to a specified force, "(t)he seat shall not deflect by an amount such that any part of the seat moves to within 4 inches of any part of another passenger seat in its originally installed position." In the enclosed letter to Mr. Hiler, the agency stated that "once the restraining bar is attached to the seatback, it is part of the seatback." Therefore, the R-BAR would be considered a part of the seat subject to the requirements of S5.1.4.(c)

Section S5.1.4(c)'s requirements are not limited to rigid components of a seat, and therefore the fact that the R-BAR is not a fixed position device is not relevant to the applicability of those requirements. With respect to your argument that the device will move upward and away in the event of a rear impact, Standard No. 222 sets forth a specific test procedure for the requirement specified in S5.1.4(c). Manufacturers are required to certify that a vehicle complies with the requirements of the standard when tested in accordance with that test procedure.

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

Enclosures

ref:222 d:5/14/92

1992

ID: 7175

Open

Mr. Raymond B. Kesler
Kesler Research Enterprises
5508 Cahuenga Blvd.
North Hollywood, CA 91601

Dear Mr. Kesler:

This responds to your February 29, 1992 letter asking the agency to reconsider its decision to deny your earlier petition for rulemaking to amend Federal motor vehicle safety standard No. 111, Rearview Mirrors. As explained below, your request is again denied, for the same reasons explained in the previous denial.

You initially petitioned the agency to amend Standard No. 111 to require passenger side convex mirrors to have a radius of curvature of 25 inches and to have a plastic label with a ring indicator applied to these mirrors. After reviewing the petition, the agency denied your request, finding that (1) a safety need for a wider field of view for passenger side convex mirrors had not been established and (2) your suggested mirror system would, by comparison with currently specified convex mirror systems, have increased distortion and reduced a driver's depth perception and judgment about another vehicle's closing speed. (56 FR 42715; August 29, 1991).

In your February 29, 1992 correspondence, styled a "petition for reconsideration," you restated your previous request for the agency to amend Standard No. 111 to require a mirror with a 25 inch radius of curvature and a plastic label with a ring indicator applied to these mirrors. That request does not provide any new information beyond what was presented in your initial petition.

Petitions for reconsideration may be filed only in response to an agency rule. See 49 CFR 553.35(a). A denial of a petition for rulemaking is not a rule, since such denials do not amend any existing provision in the Code of Federal Regulations. Thus, your correspondence is not a petition for reconsideration.

It is possible that there might be instances in which additional information has become available since the agency considered and denied the initial petition for rulemaking. If such a situation were to arise, the petitioner could file a new petition for rulemaking, asking again for the requested action based upon the newly available information. NHTSA would consider this as a petition for rulemaking. As noted above, your correspondence did not provide any new information. Thus, your correspondence is not a petition for rulemaking. Instead, your correspondence is simply a request for NHTSA to take the same action you previously asked us to take in a petition for rulemaking. Absent any new information, there is no reason for NHTSA to reexamine its previous conclusion on this matter.

I would like to take this opportunity to clarify what appears to be a misunderstanding of the agency's regulations on your part. In your February 29, 1992 correspondence, you made the statement that your product "should be approved to be made available to the driver as an optional choice." In our notice denying your petition, the agency tried to make clear that products like your convex mirror with a ring sensor label are not prohibited from being installed on vehicles by the current requirements in Standard No. 111. However, such mirrors are permitted only as supplements to the required mirrors, for the safety reasons explained at length in the denial notice. See 56 FR 42716; August 29, 1991. Hence, your product may be installed as a supplement to the required mirrors on current vehicles, without any amendments to Standard No. 111.

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.

Sincerely,

Paul Jackson Rice Chief Counsel ref:111 d:5/14/92

1992

ID: 7196

Open

Mr. Gonshiro Miyoshi
Manager, Design Administration Dept.
Technical Division Ichikoh Industries, Inc.
80 Itado, Isehara-City
Kanagawa, 259-11 Japan

Dear Mr. Miyoshi:

This responds to your letter of April 6, 1992, asking for an interpretation of Standard No. 108. With respect to a headlamp system consisting of two lamps, each containing two light sources, you have asked "Is it permissible to have the bulb center of the lower beam lower than that of the upper beam (maximum height difference is 10mm) if they are arranged horizontally?"

Paragraph S7.5(d)(2) specifies the manner in which "the lower and upper beams of a headlamp system consisting of two lamps, each containing either one or two light sources, shall be provided . . ." In such headlamps where each light source provides a beam, the lower beam is provided "by the outboard light source (or upper one if arranged vertically)," and the upper beam is provided "by the inboard light source (or the lower one if arranged vertically)."

Although the standard could be presumed to contemplate that two light sources within a headlamp would be located on the same horizontal or vertical plane, there is no specific requirement for light source placement. Because the difference in the horizontal mounting planes for bulb centers in your design is only 10mm, this difference is not sufficient to conclude that the light sources are vertically arranged, thus requiring that the lower beam bulb center be the "upper" one, or on a plane that is higher. However, for your design to be permissible, the lower beam in this essentially horizontal array must be provided by the outboard light source in the headlamps as specified in S7.5(d)(2).

Sincerely,

Paul Jackson Rice Chief Counsel

ref:108 d:5/8/92

1992

ID: 7200

Open

Mr. Neil Friedkin
Attorney at Law
325 Exterior Street
Bronx, NY 10451

Dear Mr. Friedkin:

This responds to your follow-up letter to the agency requesting that the agency provide "the applicable 1986 standard for convertible passenger cars." In an earlier letter, you had asked about our regulations with respect to converting a vehicle from a hardtop to a convertible. I am pleased to have this opportunity to respond to your inquiry.

To begin, there is no single standard applicable to convertible passenger cars, or any other motor vehicles. Instead, the National Highway Traffic Safety Administration (NHTSA) is authorized under the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1381 et seq.; Safety Act) to issue safety standards applicable to new motor vehicles and items of motor vehicle equipment. We have exercised this authority to establish many standards that apply to passenger cars, including convertible passenger cars. These standards, which are collectively called the Federal motor vehicle safety standards, are set forth in 49 CFR Part 571. They cover many different vehicle systems, including controls and displays, vehicle lighting, braking, occupant crash protection, and fuel system integrity.

As you review the safety standards in Part 571 to see which aspects of performance are of particular interest to you, you will see that the standards are generally identical for passenger cars and convertible passenger cars. There are some differences, however, including the permissible location for the center high mounted stop lamp (S5.3.1.8 of Standard No. 108, Lamps, Reflective Devices and Associated Equipment) and the inapplicability of the roof crush standard to convertibles (S3 of Standard No. 216, Roof Crush Resistance). Additionally, Standard No. 208, Occupant Crash Protection, required the front outboard seating positions of 1986 passenger cars that were not equipped with automatic crash protection (either air bags or automatic belts) to be equipped with a lap/shoulder belt and all other seating positions to be equipped with either a lap belt or a lap/shoulder belt (S4.1.2.3.1 of Standard No. 208). However, convertible passenger cars were permitted to offer either a lap belt or a lap/shoulder belt at every designated seating position, including the front outboard positions (S4.1.2.3.2 of Standard No. 208.

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.

Sincerely,

Paul Jackson Rice Chief Counsel

Ref:108#208#216 d:6/l5/92

1970

ID: 7206-2

Open

The Honorable Phil Gramm
United States Senate
2323 Bryan Street, #1500
Dallas, Texas 75201

Dear Senator Gramm:

Thank you for your letter on behalf of your constituent, Mr. Frank Sonzala, Senior Vice President of International Transquip Industries (ITI), regarding Federal Motor Vehicle Safety Standard No. 121, Air Brake Systems. ITI is a manufacturer of air brake systems and is apparently having difficulty selling its product to vehicle manufacturers because of a compliance issue related to Standard No. 121. The National Highway Traffic Safety Administration's Chief Counsel, Paul Jackson Rice, reviewed Mr. Sonzala's concerns, and I am pleased to provide you the following information.

By way of background information, NHTSA issues Federal motor vehicle safety standards under the National Traffic and Motor Vehicle Safety Act (Safety Act). The agency does not provide approvals of motor vehicles or motor vehicle equipment. Instead, the Safety Act requires manufacturers to certify that their vehicles or equipment comply with applicable safety standards.

Standard No. 121 specifies braking requirements for vehicles equipped with air brake systems. The purpose of the standard is to ensure safe braking performance under normal and emergency conditions. The standard applies only to motor vehicles and not to motor vehicle equipment. Therefore, vehicle manufacturers are responsible for ensuring compliance with the standard, and not brake equipment manufacturers such as ITI.

The dispute between ITI and the vehicle manufacturers (ITI uses the term "original equipment manufacturers") relates to the standard's parking brake requirements. The specific requirement at issue, set forth at S5.6 of Standard No. 121, requires a vehicle's parking brake to meet certain grade holding requirements (or other equivalent requirements) with "any single leakage-type failure" of certain parts, including service brake chamber diaphragms.

The purpose of this requirement is to ensure that a driver can safely park his or her vehicle in the event of a leakage-type failure in the service brake system. Leakage- type failures include such things as ruptured or severed brake hoses and torn diaphragms. Since these types of failures are relatively common in air brake systems, NHTSA believes that it is important that drivers be able to safely secure heavy trucks and other vehicles with such failures, until the vehicles can be repaired.

For the purpose of determining whether a vehicle can meet Standard No. 121's grade holding requirements with one particular leakage-type failure, a failed diaphragm, ITI would like the standard to be interpreted to cover only a very limited and specific type of failure, i.e., a hole 1/8 inch in size located in a particular place. ITI states that the vehicle manufacturers generally have a broader view of what constitutes a failed diaphragm, i.e., they believe that failures include holes larger than 1/8 inch. ITI argues that Standard No. 121 is ambiguous in this area and requests NHTSA to issue an interpretation supporting its position.

After consulting with NHTSA's Chief Counsel, we can state that the vehicle manufacturers are correct in their understanding that a failed diaphragm is not limited to a diaphragm with a 1/8 inch hole. Therefore, if a vehicle cannot pass Standard No. 121's grade holding test with a larger hole in a failed diaphragm, the vehicle manufacturer cannot certify that the vehicle complies with the standard. Further, we disagree with ITI's contention that Standard No. 121 is ambiguous as to what constitutes a failed diaphragm.

As indicated above, Standard No. 121 specifies that the grade holding requirements must be met with any single leakage-type failure of certain parts, including a failed diaphragm. The usage of the term "any," when used in connection with a set of items, is specifically defined at 49 CFR 571.4 as meaning the totality of that set of items, any one of which may be selected by the Administration for testing. Thus, a vehicle must meet the grade holding requirements regardless of the extent of the failure selected by NHTSA for testing.

We note that leakage-type failures of many types and sizes can occur in vehicle brake systems. NHTSA intentionally did not limit the size or location of such failures in developing this requirement to ensure that a vehicle has adequate grade holding performance regardless of the specific nature of such a failure. ITI also asked whether other broken components, such as heavy parking springs, brake shoes, linings, and drums should be part of Standard No. 121's test requirements, since diaphragms are tested when torn. Although NHTSA's brake standards do not have any express test requirements for broken parking springs, brake shoes, linings or drums, those standards include a number of requirements to ensure adequate braking performance in the event of various failures in a vehicle's brake system.

We hope that this information is helpful.

Sincerely,

Frederick H. Grubbe

Enclosure: Constituents Correspondence

cc: Washington Office

Ref: 121 d:5/20/92

1992

ID: 7206

Open

The Honorable Phil Gramm
United States Senate
2323 Bryan Street, #1500
Dallas, Texas 75201

Dear Senator Gramm:

Thank you for your letter on behalf of your constituent, Mr. Frank Sonzala, Senior Vice President of International Transquip Industries (ITI), regarding Federal Motor Vehicle Safety Standard No. 121, Air Brake Systems. ITI is a manufacturer of air brake systems and is apparently having difficulty selling its product to vehicle manufacturers because of a compliance issue related to Standard No. 121. The National Highway Traffic Safety Administration's Chief Counsel, Paul Jackson Rice, reviewed Mr. Sonzala's concerns, and I am pleased to provide you the following information.

By way of background information, NHTSA issues Federal motor vehicle safety standards under the National Traffic and Motor Vehicle Safety Act (Safety Act). The agency does not provide approvals of motor vehicles or motor vehicle equipment. Instead, the Safety Act requires manufacturers to certify that their vehicles or equipment comply with applicable safety standards.

Standard No. 121 specifies braking requirements for vehicles equipped with air brake systems. The purpose of the standard is to ensure safe braking performance under normal and emergency conditions. The standard applies only to motor vehicles and not to motor vehicle equipment. Therefore, vehicle manufacturers are responsible for ensuring compliance with the standard, and not brake equipment manufacturers such as ITI.

The dispute between ITI and the vehicle manufacturers (ITI uses the term "original equipment manufacturers") relates to the standard's parking brake requirements. The specific requirement at issue, set forth at S5.6 of Standard No. 121, requires a vehicle's parking brake to meet certain grade holding requirements (or other equivalent requirements) with "any single leakage-type failure" of certain parts, including service brake chamber diaphragms.

The purpose of this requirement is to ensure that a driver can safely park his or her vehicle in the event of a leakage-type failure in the service brake system. Leakage- type failures include such things as ruptured or severed brake hoses and torn diaphragms. Since these types of failures are relatively common in air brake systems, NHTSA believes that it is important that drivers be able to safely secure heavy trucks and other vehicles with such failures, until the vehicles can be repaired.

For the purpose of determining whether a vehicle can meet Standard No. 121's grade holding requirements with one particular leakage-type failure, a failed diaphragm, ITI would like the standard to be interpreted to cover only a very limited and specific type of failure, i.e., a hole 1/8 inch in size located in a particular place. ITI states that the vehicle manufacturers generally have a broader view of what constitutes a failed diaphragm, i.e., they believe that failures include holes larger than 1/8 inch. ITI argues that Standard No. 121 is ambiguous in this area and requests NHTSA to issue an interpretation supporting its position.

After consulting with NHTSA's Chief Counsel, we can state that the vehicle manufacturers are correct in their understanding that a failed diaphragm is not limited to a diaphragm with a 1/8 inch hole. Therefore, if a vehicle cannot pass Standard No. 121's grade holding test with a larger hole in a failed diaphragm, the vehicle manufacturer cannot certify that the vehicle complies with the standard. Further, we disagree with ITI's contention that Standard No. 121 is ambiguous as to what constitutes a failed diaphragm.

As indicated above, Standard No. 121 specifies that the grade holding requirements must be met with any single leakage-type failure of certain parts, including a failed diaphragm. The usage of the term "any," when used in connection with a set of items, is specifically defined at 49 CFR 571.4 as meaning the totality of that set of items, any one of which may be selected by the Administration for testing. Thus, a vehicle must meet the grade holding requirements regardless of the extent of the failure selected by NHTSA for testing.

We note that leakage-type failures of many types and sizes can occur in vehicle brake systems. NHTSA intentionally did not limit the size or location of such failures in developing this requirement to ensure that a vehicle has adequate grade holding performance regardless of the specific nature of such a failure. ITI also asked whether other broken components, such as heavy parking springs, brake shoes, linings, and drums should be part of Standard No. 121's test requirements, since diaphragms are tested when torn. Although NHTSA's brake standards do not have any express test requirements for broken parking springs, brake shoes, linings or drums, those standards include a number of requirements to ensure adequate braking performance in the event of various failures in a vehicle's brake system.

We hope that this information is helpful.

Sincerely,

Frederick H. Grubbe

Enclosure: Constituents Correspondence

cc: Washington Office

ref:121 d:5/20/92

1992

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.