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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 211 - 220 of 2067
Interpretations Date

ID: nht94-7.28

Open

DATE: March 23, 1994

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Richard A. Zander -- AlliedSignal Automotive Proving Grounds (New Carlisle, IN)

TITLE: None

ATTACHMT: Attached to letter dated 5/19/93 from Richard A. Zander to NHTSA Office of Chief Council

TEXT:

This responds to your letter asking about the fade and recovery requirements of Federal Motor Vehicle Safety Standard No. 105, Hydraulic Brake Systems. I apologize for the delay in our response. You noted that the standard requires vehicles with a GVWR of 10,000 pounds or less to be capable of making a specified number of fade stops "at a deceleration not lower than 15 fpsps for each stop." You stated that you are aware of a number of different understandings within the industry of the quoted phrase, and requested an interpretation as to whether vehicles must be capable of maintaining an average deceleration of at least 15 fpsps or a minimum deceleration of at least 15 fpsps. As discussed below, vehicles must be capable of maintaining a minimum deceleration of at least 15 fpsps.

By way of background information, the National Traffic and Motor Vehicle Safety Act (15 U.S.C. S 1381, et seq.) authorizes the National Highway Safety Administration (NHTSA) to issue safety standards applicable to new motor vehicles and items of motor vehicle equipment. NHTSA does not, however, approve motor vehicles or motor vehicle equipment. Instead, the Safety Act establishes a "self-certification" process under which each manufacturer is responsible for certifying that its products meet all applicable safety standards.

Manufacturers must have some independent basis for their certification that a product complies with all applicable safety standards. This does not necessarily mean that a manufacturer must conduct the specific tests set forth in an applicable standard. Certifications may be based on, among other things, engineering analyses, actual testing, and computer simulations. Whatever the basis for certification, however, the manufacturer must certify that the product complies with a standard as it is written, i.e., that the vehicle will pass all applicable requirements if it is tested exactly according to the standard's test conditions and other specifications.

Standard No. 105's fade and recovery test requirements are set forth in S5.1.4. These requirements must be met under the conditions prescribed in S6, when tested according to the procedures set forth in S7. See S5.1. The purpose of the fade and recovery test requirements is to help ensure that brakes retain adequate stopping capacity during and after exposure to conditions caused by prolonged or severe use, such as long, downhill driving.

The standard specifies two fade and recovery tests for vehicles with a GVWR of 10,000 pounds or less. Each of the fade and recovery tests consists of three parts: (1) baseline check stops, (2) fade stops, and (3) recovery stops. The requirements for the fade stops are set forth in S5.1.4.2(a), which states that:

Each vehicle with a GVWR of 10,000 lbs or less shall be capable of making 5 fade stops (10 fade stops on the second test) from 60 mph at a deceleration not lower than 15 fpsps for each stop, followed by 5 fade stops at the maximum deceleration attainable from 5 to 15 fpsps."

As noted, S5.1.4.2(a) must be read in conjunction with S7.11.2.1, which sets forth the procedure for conducting the fade stops. It reads, in relevant part, as follows:

Make 5 stops from 60 mph at 15 fpsps followed by 5 stops at the maximum attainable deceleration between 5 and 15 fpsps for each stop. ... Attain the REQUIRED DECELERATION within 1 second and, AS A MINIMUM, MAINTAIN IT for the remainder of the stopping time.

Control force readings may be terminated when the vehicle speed falls to 5 mph. (Emphasis added.)

The words "required deceleration" in S7.11.2.1 refer to 15 fpsps. (That value is set forth both in S5.1.4.2(a) and the first sentence of S7.11.2.1.) Thus, in conducting fade stops, within one second of beginning a stop, a deceleration of 15 fpsps must be attained. S7.11.2.1 then specifies that, "as a minimum," the required deceleration (15 fpsps) must be maintained for the remainder of the stopping time. (The word "it" in the highlighted sentence refers back to the phrase "required deceleration.") Thus, after a deceleration of 15 fpsps is attained (within one second of beginning the stop), the deceleration cannot drop below 15 fpsps even momentarily.

You stated that you are aware of the following three understandings within the industry concerning the meaning of this requirement:

1. The average deceleration for the stop must be greater than 15 fpsps. The average deceleration is calculated one second after the stop begins to a vehicle speed of 5 mph.

2. After 1 second the deceleration can not drop below 15 fpsps even for an instant. If the deceleration drops below 15 fpsps at any time it is considered a failure even if the average deceleration is greater than 15 fpsps.

3. The average deceleration for the stop must be greater than 15 fpsps and the deceleration must be greater than 15 fpsps for at least 75% of the stop excluding the first second of the stop.

Of the three understandings, the first and third are inconsistent with the plain wording of S7.11.2.1 which specifies that, after the required 15 fpsps deceleration is attained (within one second of beginning the stop), it must, as a MINIMUM, be maintained for the remainder of the stopping time. The first and third understandings would, among other things, replace S7.11.2.1's specification that the 15 fpsps deceleration be maintained as a "minimum" with one that it be maintained as an "average." The second understanding is largely correct. It is correct to state that, in conducting a fade stop, after a 15 fpsps deceleration is attained (within one second of beginning the stop), the deceleration cannot drop below 15 fpsps even

for an instant. However, if the deceleration did drop below 15 fpsps, that would not necessarily indicate a "failure" but might simply be an invalid test. As you note in your letter, a deceleration might fall below 15 fpsps because the driver did not compensate for in-stop fade. However, if a vehicle was unable to pass Standard No. 105's fade stop test requirements at the specified deceleration rates, it would not comply with the standard, notwithstanding the fact that it might be able to pass the requirements at slightly lower deceleration rates.

You stated in your letter that the second understanding appears to not consider the intent of the fade procedure, the intent being that a vehicle must be capable of making multiple high deceleration stops in a short period of time without drastic changes in effectiveness. As discussed above, the purpose of the fade and recovery test requirements is to help ensure that brakes retain adequate stopping capacity during and after exposure to conditions caused by prolonged or severe use, such as long, downhill driving. If a vehicle was unable to pass Standard No. 105's fade stop test requirements at the specified deceleration rates, it would indicate inadequate stopping capability during conditions caused by prolonged or severe use, such as long, downhill driving.

You also stated that in the Laboratory Test Procedure for Standard No. 105, published by NHTSA's Office of Vehicle Safety Compliance (OVSC), the data sheet for the fade stops requests the following information for the deceleration: "Average Sust Decel." You stated that it therefore appears that NHTSA's interpretation of the phrase "at a deceleration not lower than 15 fpsps for each stop" is "the average sustained deceleration."

It is incorrect to interpret the OVSC Laboratory Test Procedures as limiting the requirements of the Federal motor vehicle safety standards. I call your attention to the following note which is set forth at the beginning of the Laboratory Test Procedure:

The OVSC Laboratory Test Procedures, prepared for use by independent laboratories under contract to conduct compliance tests for the OVSC, are not intended to limit the requirements of the applicable FMVSS(s).

In some cases, the OVSC Laboratory Test Procedures do not include all of the various FMVSS minimum performance requirements. Sometimes, recognizing applicable test tolerances, the Test Procedures specify test conditions which are less severe than the minimum requirements of the standards themselves. Therefore, compliance of a vehicle or item of motor vehicle equipment is not necessarily guaranteed if the manufacturer limits certification tests to those described in the OVSC Laboratory Test Procedures.

I am enclosing a copy of the most recent version of the Laboratory Test Procedure for Standard No. 105, in response to your request. I hope this information is helpful. If you have any further questions, please feel free to contact David Elias of my staff at this address or by telephone at (202) 366- 2992.

ID: nht94-1.93

Open

TYPE: Interpretation-NHTSA

DATE: March 23, 1994

FROM: John Womack -- Acting Chief Counsel, NHTSA

TO: Richard A. Zander -- AlliedSignal Automotive Proving Grounds (New Carlisle, IN)

TITLE: None

ATTACHMT: Attached to letter dated 5/19/93 from Richard A. Zander to NHTSA Office of Chief Council

TEXT:

This responds to your letter asking about the fade and recovery requirements of Federal Motor Vehicle Safety Standard No. 105, Hydraulic Brake Systems. I apologize for the delay in our response. You noted that the standard requires vehicles with a GVWR of 10,000 pounds or less to be capable of making a specified number of fade stops "at a deceleration not lower than 15 fpsps for each stop." You stated that you are aware of a number of different understandings within the industry of the quoted phrase, and requested an interpretation as to whether vehicles must be capable of maintaining an average deceleration of at least 15 fpsps or a minimum deceleration of at least 15 fpsps. As discussed below, vehicles must be capable of maintaining a minimum dec eleration of at least 15 fpsps.

By way of background information, the National Traffic and Motor Vehicle Safety Act (15 U.S.C. S 1381, et seq.) authorizes the National Highway Safety Administration (NHTSA) to issue safety standards applicable to new motor vehicles and items of motor ve hicle equipment. NHTSA does not, however, approve motor vehicles or motor vehicle equipment. Instead, the Safety Act establishes a "self-certification" process under which each manufacturer is responsible for certifying that its products meet all appli cable safety standards.

Manufacturers must have some independent basis for their certification that a product complies with all applicable safety standards. This does not necessarily mean that a manufacturer must conduct the specific tests set forth in an applicable standard. Certifications may be based on, among other things, engineering analyses, actual testing, and computer simulations. Whatever the basis for certification, however, the manufacturer must certify that the product complies with a standard as it is written, i.e., that the vehicle will pass all applicable requirements if it is tested exactly according to the standard's test conditions and other specifications.

Standard No. 105's fade and recovery test requirements are set forth in S5.1.4. These requirements must be met under the conditions prescribed in S6, when tested according to the procedures set forth in S7. See S5.1. The purpose of the fade and recover y test requirements is to help ensure that brakes retain adequate stopping capacity during and after exposure to conditions caused by prolonged or severe use, such as long, downhill driving.

The standard specifies two fade and recovery tests for vehicles with a GVWR of 10,000 pounds or less. Each of the fade and recovery tests consists of three parts: (1) baseline check stops, (2) fade stops, and (3) recovery stops. The requirements for t he fade stops are set forth in S5.1.4.2(a), which states that:

Each vehicle with a GVWR of 10,000 lbs or less shall be capable of making 5 fade stops (10 fade stops on the second test) from 60 mph at a deceleration not lower than 15 fpsps for each stop, followed by 5 fade stops at the maximum dec eleration attainable from 5 to 15 fpsps."

As noted, S5.1.4.2(a) must be read in conjunction with S7.11.2.1, which sets forth the procedure for conducting the fade stops. It reads, in relevant part, as follows:

Make 5 stops from 60 mph at 15 fpsps followed by 5 stops at the maximum attainable deceleration between 5 and 15 fpsps for each stop. ... Attain the REQUIRED DECELERATION within 1 second and, AS A MINIMUM, MAINTAIN IT for the remaind er of the stopping time. Control force readings may be terminated when the vehicle speed falls to 5 mph. (Emphasis added.)

The words "required deceleration" in S7.11.2.1 refer to 15 fpsps. (That value is set forth both in S5.1.4.2(a) and the first sentence of S7.11.2.1.) Thus, in conducting fade stops, within one second of beginning a stop, a deceleration of 15 fpsps must be attained. S7.11.2.1 then specifies that, "as a minimum," the required deceleration (15 fpsps) must be maintained for the remainder of the stopping time. (The word "it" in the highlighted sentence refers back to the phrase "required deceleration.") Thus, after a deceleration of 15 fpsps is attained (within one second of beginning the stop), the deceleration cannot drop below 15 fpsps even momentarily.

You stated that you are aware of the following three understandings within the industry concerning the meaning of this requirement:

1. The average deceleration for the stop must be greater than 15 fpsps. The average deceleration is calculated one second after the stop begins to a vehicle speed of 5 mph.

2. After 1 second the deceleration can not drop below 15 fpsps even for an instant. If the deceleration drops below 15 fpsps at any time it is considered a failure even if the average deceleration is greater than 15 fpsps.

3. The average deceleration for the stop must be greater than 15 fpsps and the deceleration must be greater than 15 fpsps for at least 75% of the stop excluding the first second of the stop.

Of the three understandings, the first and third are inconsistent with the plain wording of S7.11.2.1 which specifies that, after the required 15 fpsps deceleration is attained (within one second of beginning the stop), it must, as a MINIMUM, be maintain ed for the remainder of the stopping time. The first and third understandings would, among other things, replace S7.11.2.1's specification that the 15 fpsps deceleration be maintained as a "minimum" with one that it be maintained as an "average."

The second understanding is largely correct. It is correct to state that, in conducting a fade stop, after a 15 fpsps deceleration is attained (within one second of beginning the stop), the deceleration cannot drop below 15 fpsps even

for an instant. However, if the deceleration did drop below 15 fpsps, that would not necessarily indicate a "failure" but might simply be an invalid test. As you note in your letter, a deceleration might fall below 15 fpsps because the driver did not co mpensate for in-stop fade. However, if a vehicle was unable to pass Standard No. 105's fade stop test requirements at the specified deceleration rates, it would not comply with the standard, notwithstanding the fact that it might be able to pass the req uirements at slightly lower deceleration rates.

You stated in your letter that the second understanding appears to not consider the intent of the fade procedure, the intent being that a vehicle must be capable of making multiple high deceleration stops in a short period of time without drastic changes in effectiveness. As discussed above, the purpose of the fade and recovery test requirements is to help ensure that brakes retain adequate stopping capacity during and after exposure to conditions caused by prolonged or severe use, such as long, downhi ll driving. If a vehicle was unable to pass Standard No. 105's fade stop test requirements at the specified deceleration rates, it would indicate inadequate stopping capability during conditions caused by prolonged or severe use, such as long, downhill driving.

You also stated that in the Laboratory Test Procedure for Standard No. 105, published by NHTSA's Office of Vehicle Safety Compliance (OVSC), the data sheet for the fade stops requests the following information for the deceleration: "Average Sust Decel." You stated that it therefore appears that NHTSA's interpretation of the phrase "at a deceleration not lower than 15 fpsps for each stop" is "the average sustained deceleration."

It is incorrect to interpret the OVSC Laboratory Test Procedures as limiting the requirements of the Federal motor vehicle safety standards. I call your attention to the following note which is set forth at the beginning of the Laboratory Test Procedure :

The OVSC Laboratory Test Procedures, prepared for use by independent laboratories under contract to conduct compliance tests for the OVSC, are not intended to limit the requirements of the applicable FMVSS(s). In some cases, the OVSC Laboratory Test Procedures do not include all of the various FMVSS minimum performance requirements. Sometimes, recognizing applicable test tolerances, the Test Procedures specify test conditions which are les s severe than the minimum requirements of the standards themselves. Therefore, compliance of a vehicle or item of motor vehicle equipment is not necessarily guaranteed if the manufacturer limits certification tests to those described in t he OVSC Laboratory Test Procedures.

I am enclosing a copy of the most recent version of the Laboratory Test Procedure for Standard No. 105, in response to your request. I hope this information is helpful. If you have any further questions, please feel free to contact David Elias of my st aff at this address or by telephone at (202) 366- 2992.

ID: aiam5548

Open
Mr. Richard Kreutziger Executive Director New York State Bus Distributors Association 102 Grace Street Penn Yan, NY 14527; Mr. Richard Kreutziger Executive Director New York State Bus Distributors Association 102 Grace Street Penn Yan
NY 14527;

"Dear Mr. Kreutziger: This responds to your fax of May 4, 1994 requesting information on a May 4, 1994, final rule (59 FR 22997) delaying the effective date of one section of the November 2, 1992, final rule amending Standard No. 217, Bus Emergency Exits and Window Retention and Release (57 FR 49413). Your letter enclosed a bulletin from Carpenter Manufacturing, Inc. concerning 'options' which can be deleted because of the delay of effective date. Your fax notes that New York state regulations exceed the minimum requirements of Standard No. 217 and requested any information we can provide on how the delay of effective date affects buses in the State of New York. The November 2, 1992, amendment to Standard No. 217 set requirements for the provision of emergency exits based upon the seating capacity of the school bus (S5.2), set performance requirements for emergency exit window and emergency roof exit release (S5.3), revised the extension requirements for side doors and set extension requirements for emergency roof exits (S5.4), and revised the identification requirements (S5.5). The May 4, 1994, delay of effective date affects only the amendments to S5.2. Provision of Emergency Exits (S5.2) The November 2, 1992, final rule revised S5.2.3 to specify the number and type of exits required on school buses. As amended, S5.2.3 states, in part: The area in square centimeters of the unobstructed openings for emergency exit shall collectively amount to at least 432 times the number of designated seating positions in the bus. The amount of emergency exit area credited to an emergency exit is based on the daylight opening of the exit opening. The section also specifies the type of emergency exits which must be installed to meet this requirement. All school buses are required to have either a rear emergency exit door or a side emergency exit door and a rear push-out window. These are the same exits required by S5.2.3.1 of Standard No. 217 before the recent amendments. The November 1992 rule amended S5.2.3.1 by specifying additional exits to meet the new minimum area requirement of S5.2.3. If, after deducting the daylight opening of the front service door and the required exit(s), additional exits are needed to meet the minimum area requirement of S5.2.3, any remaining exit area must be provided by installing additional exits in the following order: (1) a side emergency exit door, (2) an emergency roof exit, and (3) any combination of emergency exit doors, emergency roof exits, and emergency exit windows. The May 4, 1994 final rule delayed the effective date of the amendment of S5.2.3.1 only. The effect of the delay is that, until September 1, 1994, manufacturers may comply with the requirements of Standard No. 217 by installing either a rear emergency exit door, or a side emergency exit door and a rear push-out window. Your letter notes that New York regulations exceed Standard No. 217 in that they require additional exits. Section 103(d) of the National Traffic and Motor Vehicle Safety Act (the Safety Act, 15 U.S.C. 1392(d)) provides that: Whenever a Federal motor vehicle safety standard ... is in effect, no State or political subdivision of a State shall have any authority either to establish, or to continue in effect, with respect to any motor vehicle or item of motor vehicle equipment any safety standard applicable to the same aspect of performance of such vehicle or item of equipment which is not identical to the Federal standard. Nothing in this section shall be construed to prevent ... any State or political subdivision thereof from establishing a safety requirement applicable to motor vehicles or motor vehicle equipment procured for its own use if such requirement imposes a higher standard than that required to comply with the otherwise applicable Federal standard. Section 103(d) preempts state requirements for school buses covering the same aspect of performance as an applicable Federal motor vehicle safety standard that are different from the applicable standard except to the extent that the requirements impose a higher level of performance and apply only to vehicles procured for the State's use. A state law requiring exits in addition to those required by Standard No. 217 would be preempted under 103(d) to the extent that the law requires all school buses manufactured for use in the state to comply with the law. The law would not be preempted to the extent that it applies to public school buses. Any exits required by New York regulations on public school buses which exceed the requirements of Standard No. 217 would be considered voluntarily installed for purposes of federal law. Emergency Exit Release (S5.3) The November 2, 1992, final rule added performance requirements for the release mechanisms for emergency exit windows and emergency roof exits on school buses. These requirements apply both to required exits and to voluntarily installed exits. Thus, if New York requires either emergency exit windows or emergency roof exits, the manufacturer must certify that the release mechanisms comply with the requirements of S5.3. The effective date for the amendments to S5.3 was not extended by the May 4, 1994, final rule. Emergency Exit Extension (S5.4) The November 2, 1992, final rule revised the extension requirements for side emergency exit doors on school buses and set extension requirements for emergency roof exits on school buses. These requirements apply both to required exits and to voluntarily installed exits. Thus, if New York requires either side emergency exit doors or emergency roof exits, the manufacturer must certify that the vehicle complies with the new extension requirements. The effective date for the amendments to S5.4 was not extended by the May 4, 1994, final rule. I note that the bulletin enclosed with your letter implies that, due to the delay of the effective date of the November 2, 1992, final rule, flip-up seats are not needed to meet the new requirements of S5.4. This information appears to be incorrect, since the May 4, 1994, final rule did not delay the effective date of S5.4. Compliance with the new requirements of S5.4 might entail the installation of flip-up seats. Under the new requirements, side emergency exit doors are required to provide an opening at least 114 centimeters high and 61 centimeters wide. In addition, an aisle 30 centimeters wide (referenced to the rear edge of the door) must be provided from the longitudinal centerline of the bus to the exit. A seat bottom is allowed within this aisle if it flips up when not in use such that it no longer is within the aisle. Finally, no portion of a seat or restraining barrier may block access to the latch. Thus, if New York requires side emergency exit doors, flip-up seats adjacent to those exits might have to be used to enable the bus to meet these requirements. For example, a flip-up seat might be needed to meet the requirement that the aisle for a side exit must be at least 30 centimeters wide. Emergency Exit Identification (S5.5) Finally, the November 2, 1992, final rule revised the identification requirements (S5.5). The effective date for the amendments to S5.5 was not extended by the May 4, 1994, final rule. As revised, each required emergency exit is required to be marked with the words 'Emergency Door' or 'Emergency Exit.' For emergency exit doors, the location of this marking was not changed. For emergency window exits and emergency roof exits, location requirements were added. In addition, each required emergency exit must be outlined with retroreflective tape. The identification requirements do not apply to voluntarily installed emergency exits (i.e., exits in excess of those required by S5.2.3). Please note that there was a discrepancy concerning the size of the retroreflective tape caused by the metric conversion in the November 2, 1992, final rule. In a July 7, 1993, letter to Mr. Thomas D. Turner of the Blue Bird Body Company NHTSA stated that it would issue a correction notice that would specify a minimum size of 2.5 cm for the tape. Until the correction is issued, NHTSA will not take enforcement measures regarding tape size against a manufacturer who uses 1 inch wide retroreflective tape. I have enclosed a copy of the May 4, 1994, final rule for your use. 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, John Womack Acting Chief Counsel cc: Mr. Todd Bontrager Asst. Vice President of Sales School Bus Division Carpenter Manufacturing, Inc. Mitchell, IN 47446 Enclosure";

ID: nht89-1.23

Open

TYPE: INTERPRETATION-NHTSA

DATE: 02/21/89

FROM: T. CHIKADA -- MGR., AUTOMOTIVE LIGHTING, ENGINEERING CONTROL DEPT., STANLEY ELECTRIC CO., LTD.

TO: ERIKA Z. JONES -- CHIEF COUNSEL, NHTSA

TITLE: INSTALLATION OF DECORATIVE EXTRA LIGHTING DEVICES ON MOTORCYCLES, WHICH ARE NOT SPECIFIED IN FMVSS NO. 108

ATTACHMT: ATTACHED TO LETTER DATED 3-20-90 TO T. CHIKADA, STANLEY ELECTRIC CO., LTD., FROM STEPHEN P. WOOD, NHTSA; [A35; STD. 108]

TEXT: We have an idea of producing two decorative extra lighting devices which are not specified in FMVSS No. 108.

As shown in the attached sheet, these decorative devices will be installed on the rear face, and at the top of optional motorcycle rear trunks respectively. The distance between center of light source of device A and B is 290 mm.

The light source of device B is incandescent bulb, and that of device A is LED. Color of emitted light of both devices (A and B) is red. Both devices (A and B) are energized when tail lamp is on. And they (A and B) are so designed as to have the maximu m intensity less than that minimum intensity of tail lamp C. (It is a matter of course that the minimum and maximum intensities of tail lamp C satisfy the requirement of FMVSS No. 108.)

Please let us have your answers for the following questions.

Q.1 Is it permitted to equip a motorcycle with the above mentioned accessory lamps?

Q.2 If the answer to the above question is "YES",

1) is it acknowledged to use LED as the light source of device B?

2) should maximum intensity of each lamp (A or B) separately be less than the minimum intensity of tail lamp C? or should combined maximum intensity of both lamps (A and B) be less than the minimum intensity of tail lamp C?

We are looking forward to your advice.

(Graphics omitted)

ID: nht95-2.99

Open

TYPE: INTERPRETATION-NHTSA

DATE: May 31, 1995

FROM: John C. Golden -- Product Manager, Lighting and Electrical, Federal Mogul Corp.

TO: John Womack -- Acting Chief Counsel, U.S. DOT

TITLE: NONE

ATTACHMT: ATTACHED TO 10/16/95 LETTER FROM JOHN WOMACK TO JOHN C. GOLDEN (A43; VSA 108(a)(2)(A); STD. 125)

TEXT: Dear Mr. Womack,

We are seeking some clarification on F.M.V.S.S. 125 and how it relates to a letter you wrote Mr. John G. Klinge, Executive Vice President, Visibility Systems Company dated 12 August, 1994.

We market a wide variety of lighting and safety devices under the brand name Signal-State. Mr. Klinge provided us a copy of your written response to his inquiry before we chose to go ahead and market his product under our name.

Now, Mr. Klinge would like us to market a three-pack version of his battery operated safety strobe device (an equilateral triangle measuring 3 1/2" on each side) that is, in our opinion, specifically designed for use on DOT warning triangles. We think i t is a terrific idea. However, before we market this item we have one question:

The requirement for warning triangles is for 17" (minimum) leg length and 2" (minimum) leg width. The red reflector must be 1/2" (minimum) width. Does the mounting of one of these devices (as pictured, attached) take away minimum reflective area suc h that it would render the warning triangles illegal or ineffective?

Our greatest fear is the possibility of a motorist coming over a hill on a dark night . . . and over that hill is a broken down vehicle . . . with triangles properly deployed . . . but with a Lightman on top of each . . . with dead batteries.

If you think we should contact the Federal Highway Administration for clarification, please be kind enough to direct me to the proper person.

(Brochure Omitted.)

ID: 86-2.16

Open

TYPE: INTERPRETATION-NHTSA

DATE: 04/09/86

FROM: AUTHOR UNAVAILABLE; Erika Z. Jones; NHTSA

TO: Carl R. Walker

TITLE: FMVSS INTERPRETATION

TEXT:

Mr. Carl R. Walker Manager, Technical Sales and Service P.T. Brake Lining Company, Inc. P.O. Box 329 Lawrence, Ma 01842

Dear Mr. Walker:

This responds to your letter addressed to Mr. Richard Radlinski, concerning a statement by International Transquip alleging that the National Highway Traffic Safety Administration (NHTSA) and the Bureau of Motor Carrier Safety (BMCS) "agree" that the Mini-Max brake system produced by that company complies with Federal standards. You noted that International Transquip has referenced a June 6, 1984 letter from BMCS.

NHTSA does not provide approvals of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act, it is the responsibility of the manufacturer to ensure that its vehicles or equipment complies with applicable safety standards. I would emphasize that NHTSA has not issued any statement that could be read as "agreement" that the Mini-Max brake complies with FMVSS No. 121.

We are enclosing a copy of a letter addressed to Navistar which discusses NHTSA's position concerning the June 6, 1984 letter from BMCS. The letter also notes that the California Highway Patrol (CHP) has raised a number of issues relating to the compliance and overall safety of Mini-Max brakes in connection with a petition for rulemaking, and that International Transquip has submitted comments on CHP's analysis. We have enclosed for your information a notice granting the CHP petition and two related interpretation letters, to International Transquip and the New Jersey Division of Motor Vehicles. The CHP and Mini-Max submissions have been placed in the Petitions for Rulemaking (PRM) Docket for FMVSS No. 121. If you desire copies of those submissions, please contact: Docket Section, National Highway Traffic Safety Administration, Room 5109, 400 Seventh Street, S.W., Washington, D.C. 20590 (202-426-2768).

Sincerely,

Erika Z. Jones Chief Counsel

Enclosures

January 24, 1985

Mr. Richard Radlinski Manager, Brake Research NHSTA P. O. BOX 37 East Liberty, OH 43319

Subject: Mini-Max Brake

Dear Dick:

As per our discussion, please find a complete folder and cover letter from International Transquip Industries, Inc., manufacturers of the subject brake. Of particular concern to me is their reference to "compliance to the brake standards", by NHSTA and BMCS. "All agree that it complies to the standards."

In their literature, they make reference to a letter from BMCS (on US DOT stationary), dated June 6, 1984, which seemingly meets the parking requirements of NHSTA. All is attached for your information and reference. Even though this response from BMCS is related to a change notice, it is being interpreted as "full compliance" to FMVSS 121.

Your written clarification of this matter would be most helpful.

Very truly yours,

P.T. BRAKE LINING COMPANY, INC.

Carl R. Walker Manager, Technical Sales & Service

CRW/mdp

Enclosure

cc: Steven Doyle Jim Rabith

ID: Mills.1

Open

    Robert G. Mills, Supervisor, Homologation
    Triumph Designs Limited
    Normandy Way, Hinckley
    Leicestershire LE10 3BZ
    United Kingdom


    Dear Mr. Mills:

    This responds to your March 22, 2005, letter in which you requested clarification regarding the proper method for measuring the required edge-to-edge separation distance between a motorcycles front turn signal lamps and headlamp under Federal Motor Vehicle Safety Standard (FMVSS) No. 108, Lamps, Reflective Devices, and Associated Equipment. Specifically, your letter asked whether the minimum edge-to-edge separation distance is measured: (1) "In a 2-dimensional plane, viewed directly from the front of the motorcycle, that would only take account of the visible, vertical edge-to-edge distance between the two lamps" or (2) "In a tangential plane that would take account of the upward/downward or forward/rearward separation distance". As discussed below, our interpretation differs from the two you suggest. We interpret Standard No. 108s requirement for the separation distance between a motorcycles front turn signal lamps and headlamp as being the shortest distance between the edges of each lamps effective light-emitting surface as projected onto a two-dimensional vertical plane perpendicular to the longitudinal axis of the motorcycle (i.e. , the view that would be perceived by oncoming drivers). This projection is defined within FMVSS No. 108 as the "effective projected luminous lens area".

    By way of background, Table IV, Location of Required Equipment, of FMVSS No. 108 requires motorcycle front turn signal lamps to have a minimum edge-to-edge separation distance of four inches between these lamps and the headlamp. Our interpretation that the distance is measured with a two-dimensional frame of reference is consistent with both the purpose of the standards separation requirement and at least one prior interpretation.

    Standard No. 108 specifies a minimum separation distance between headlamps and turn signal lamps to minimize the possibility that an observer will not see the turn signal. A motorist approaching the motorcycle in oncoming traffic will perceive the required four-inch edge-to-edge separation distance in a two-dimensional plane. If measurement along a tangential plane were substituted, as in the second method identified in your letter, the perceived separation distance in this scenario may be reduced to less than four inches, as seen by the driver, and a situation could arise in which the conspicuity of the turn signal is masked by the headlamp beam. If the oncoming driver does not perceive the important information provided by the turn signal, traffic safety could be compromised.

    The minimum edge-to-edge separation distance is the shortest distance between the edges of the effective projected luminous lens areas of the two lamps. "Effective projected luminous lens area" is defined in S3 of FMVSS No. 108 as "the area of the orthogonal projection of the effective light-emitting surface of a lamp on a plane perpendicular to a defined direction relative to the axis of reference". In this case, the defined direction is the longitudinal axis of the motorcycle.

    This same reasoning and result were applied in our interpretation letter of April 23, 1986 to a party whose identity was kept confidential (see enclosure). That letter dealt with the plane of reference for measuring the separation distance between a motorcycles rear turn signals and stop/tail lamp and the view provided to traffic approaching from the rear. However, the principles and reasoning are otherwise identical to the forward-facing situation.

    We would also point out an important additional requirement for motorcycle turn signal lamp placement contained in Table IV. That requirement is that the turn signal lamps must not be closer than 16 inches, as measured from their centers.

    If you have further questions, please feel free to contact Eric Stas of my staff at this address or by telephone at (202) 366-2992.

    Sincerely,

    Jacqueline Glassman
    Chief Counsel

    Enclosure
    ref:108
    d/5/3/05

ID: nht72-6.42

Open

DATE: 08/29/72

FROM: AUTHOR UNAVAILABLE; Robert L. Carter; NHTSA

TO: B. F. Goodrich Tire Company

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your petition for rulemaking, submitted July 30, 1971, to amend Motor Vehicle Safety Standard No. 109 (49 CFR @ 571.109) and the Tire Identification and Recordkeeping Regulations (49 CFR Part 574). Your petition requests that Standard No. 109 be amended to provide for a special tire category for folding sidewall-reduced tread tires, of which the "Space Saver Spare" tire you manufacture is an example. You request specifically that requirements for these tires differ from conventional tires as follows: lower minimum breaking-energy values in the strength test (S4.2.2.4, Table II); modified minimum size factors for certain tire size designations which you list; elimination of the condition that the tire be mounted without lubricant for the bead unseating test (S4.2.2.3); and allowing the tire identification number to be placed on the lower sidewall (49 CFR 574.5). For the reasons stated below, your petition is hereby denied insofar as it requests modifications to the strength and bead unseating requirements of Standard No. 109, and the requirements of Part 574. We make certain recommendations herein regarding your request for modification of the minimum size factors of Standard No. 109.

The basis for your request for lower breaking-energy values in the strength test is that the values you request represent a level of performance equal to that of a conventional tire having the same amount of tread remaining as a new folding sidewall-reduced tread tire. The NHTSA cannot accept this argument as a valid basis for specifying lower breaking-energy value requirements for folding sidewall-reduced tread tires The requirements specified for the strength test are considered to be necessary minimum requirements for all new passenger car tires. Consequently, persons who purchase new tires, regardless of their construction, are entitled to at least this level of performance, and not the level of performance represented by a used tire.

The NHTSA does not believe, similarly, that you have presented a sufficient basis for elimination of the condition, in the bead unseating test procedure, that the tire be mounted for the test without the use of lubricant. While the NHTSA concurs in the benefits of run-flat performance, which the "Space Saver Spare" appears to provide, we do not believe that this advantage outweighs the necessity that the tire conform to the bead unseating requirements when mounted without lubrication. The NHTSA believes the possibility that tires will be mounted without lubrication in the field is sufficiently great to warrant the retention of this condition in the standard's test procedure.

We also do not consider sufficient the justification you provide for your request that the identification number required pursuant to Part 574 be allowed to be placed on the lower sidewall of the tire. Your statement to the effect that no problems are presented if the number "wears off" ignores the fact that the number must be retained on the tire for purposes of identification should a defect notification or recall campaign be instituted.

With reference to your request for modification of the (Illegible Word) size factor for the tire size designations which you list, believe B. F. Goodrich should petition, in accordance with guidelines published October 5, 1968 (33 F.R. 14964), to amend the Appendices of Standards Nos. 109 and 110 to provide that folding sidewall-reduced tread tires be added as a separate tire type, including new size designations and corresponding values for section width and minimum size factor that you consider appropriate.

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ID: aiam4969

Open
Mr. Wm. Richard Alexander Chief, Pupil Transportation Maryland State Department of Education Office of Administration and Finance 200 West Baltimore Street Baltimore, MD 21201; Mr. Wm. Richard Alexander Chief
Pupil Transportation Maryland State Department of Education Office of Administration and Finance 200 West Baltimore Street Baltimore
MD 21201;

Dear Mr. Alexander: This responds to your letter of February 18, 199 requesting confirmation 'that forward-facing wheelchairs on school buses do not need a crash barrier located forward of each wheelchair position.' As explained below, your understanding is correct. Section S5.2 of Standard No. 222, School bus passenger seating and crash protection, requires 'a restraining barrier forward of any designated seating position that does not have the rear surface of another school bus passenger seat within 24 inches of its seating reference point.' Under S5.2.1, the rear surface of the restraining barrier must be within a distance of 24 inches or less from the seating reference point. Standard No. 222's requirement for a restraining barrier does not apply to wheelchair positions. First, a wheelchair position is not technically a 'designated seating position,' as that term is defined in 49 CFR 571.3. Second, Standard No. 222's seating requirements apply only to 'school bus passenger seats.' See S1 of Standard No. 222. The term 'school bus passenger seat' is defined in S4 as 'a seat in a school bus, other than the driver's seat or a seat installed to accommodate handicapped or convalescent passengers.' I would also note that installing a crash barrier forward of a wheelchair securement location in compliance with S5.2.1 would appear to be impractical. First, the seating reference point could move depending on the type of wheelchair secured at the location. Second, many wheelchairs would not fit behind a restraining barrier complying with S5.2.1 as some are longer than 24 inches forward of the seating reference point. While the current requirements of Standard No. 222 do not have any requirements for wheelchair securement locations, NHTSA is concerned about providing crash protection for all students on school buses. NHTSA has recently published a notice of proposed rulemaking concerning requirements for wheelchair securement devices and occupant restraint systems on school buses. The notice proposed amending Standard No. 222 to include minimum strength and location requirements for the anchorages for securement and restraint devices and minimum strength requirements for the securement and restraint devices themselves. This notice did not, however, propose to require a restraining barrier forward of wheelchair securement locations. I am enclosing a copy of the notice for your information. 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 Enclosure;

ID: aiam5338

Open
Mr. John Rhein Fisher-Price, Inc. 636 Girard Ave. East Aurora, NY 14052; Mr. John Rhein Fisher-Price
Inc. 636 Girard Ave. East Aurora
NY 14052;

"Dear Mr. Rhein: This responds to your letter about the consume registration card required by Safety Standard No. 213, 'Child Restraint Systems.' I apologize for the delay in responding. You ask about three features of a registration card you wish to produce, and enclosed a sample card setting forth a 'proposed format.' You first ask whether you may specify 'Please Print' on the card. The answer is yes. NHTSA interpreted Standard 213 as permitting this feature, in an October 20, 1993 letter to Mr. Richard Glover of the Evenflo Juvenile Furniture Company. You also ask whether you may use 'open box spaces' for the consumer's name and address, to encourage consumers to print the information clearer (one character per box space). The answer is yes. NHTSA interpreted Standard 213 as permitting 'blocked squares' for the consumer's name and address in a June 14, 1993 notice (copy enclosed) denying Evenflo's petition for reconsideration of the rule that established the registration card requirement. Finally, you ask whether you may enlarge the consumer name and address space of the card, to provide consumers more space to print the information and thus increase the likelihood the information will be legible. The answer, with reference to the sample card you provided, is yes. Under S5.8 of Standard 213, the registration form must conform in size, content and format to forms depicted in the standard (figures 9a and 9b). The figures specify a minimum size for the card. Moreover, in the enclosed June 1993 notice, NHTSA explained that '(f)ormat refers to the general appearance of the form and to aspects such as type size, size and placement of margins, size and placement of the spaces for the consumer's name and address, and overall organization of the printed material.' The sample card you provided meets the minimum size requirement specified in the standard, and the general appearance and overall organization of the card is the same as that depicted in the standard (figure 9a). While the consumer name and address space is slightly larger than depicted in the standard, we conclude that this slight deviation is consistent with the standard's format requirements. This conclusion is based on the fact that this slight change does not affect the general appearance or overall organization of the card, and because the change provides consumers more space to print the information, i.e., it will not detract from the utility of the card. Please contact Ms. Deirdre Fujita of my staff at (202) 366-2992 if you have any questions. Sincerely, John Womack Acting Chief Counsel";

Request an Interpretation

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

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

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

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

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