ID: nht73-3.40

DATE: 03/08/73

FROM: AUTHOR UNAVAILABLE; Lawrence R. Schneider; NHTSA

TO: Dow Corning Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of February 26, 1973, in which you inquired whether our brake fluid standard, No. 116, has preempted State regulation with respect to silicone-based brake fluids.

As you know, Standard No. 116 does not presently contain any performance requirements for silicone-based brake fluids. The recent amendment of January 31, 1973 (38 FR 2981) only establishes labeling requirements for these fluids.

Section 103(d) of the National Traffic and Motor Vehicle Safety Act, 15 U.S.C. 1392(d), states that no State shall have a safety standard "applicable to the same aspect of performance" as a Federal standard that is not identical to the Federal standard. In this case, no "aspects of performance" at all, other than labeling, are covered by the Federal standard, so the State performance standards other than labeling cannot be said to cover the same aspects of performance. For these reasons the State performance requirements are not preempted by Standard No. 116. To hold otherwise would have the effect of voiding all State regulation of this product, leaving nothing in its place, until a Federal standard came into effect. No such results were intended by the issuance of the labeling amendment.

Work is in process to propose performance standards for silicone-based brake fluids and we plan to have requirements in effect before very much more time passes. At that time, of course, all State regulations will have to be identical to the Federal standard.

ID: nht73-3.43

DATE: 03/16/73

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Toyota Motor Sales, USA, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of January 9, 1973, concerning the application of Standard 209 to emergency locking mechanisms that Toyota intends to use in its 1974 models. Mr. Susuki of your staff presented Toyota's problem at greater length in a meeting with NHTSA on March 2, 1973, and the following response serves to confirm the opinion given him at that time.

Both the central G-sensing device (with its computer) and the individual(Illegible Word) on the retractors are considered to be seat belt assembly hardware for purposes of Standard 209. We do not find that the central position of the G-sensor is a sufficient reason to exclude it from the requirements of the standard applicable to hardware, including the corrosion requirements. However, any corrosion testing of the G-sensor would be performed with the sensor's(Illegible Word) in place. If the covering is imperious to water, as Mr. Susuki stated, there should be little difficult in passing the test.

A second question was raised by Mr. Susuki concerning the testing of the upper torso retractor. It is our opinion that the retractor should be subjected to the environmental tests in its installed condition, with its cover in place.

A final question presented by Mr. Suzuki concerns the allowable width for that portion of the upper torso belt that does not contact the occupant. As we informed him the August 1972 petition by JAMA on this subject is still open and we anticipate that the agency's action will be favorable.

ID: nht73-4.49

DATE: 08/15/73

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Adams Rite Products, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your July 25, 1973, request for copies of the Federal regulations concerning door locks and latches.

Federal Standard 206, Door Locks and Door Retention Components, is enclosed. It regulates passenger cars, multipurpose passenger vehicles, and trucks. These categories include ambulances and "motor homes", which are self-propelled units with sleeping accommodations, generally constructed on a light truck chassis. Most other "mobile homes" are not self-propelled and they qualify as trailers, which are not subject to this standard.

For your information, paragraph 9.1.2 of Ambulance Design Criteria has also been enclosed. This publication specifies the criteria which an ambulance must meet to qualify for Federal funding under the Highway Safety Program @ 402.

ENCS.

ADAMS RITE PRODUCTS, INC.

July 25, 1973

Bureau of Motor Carrier Safety Federal Highway Administration Department of Transportation Washington, D. C. 20590

Adams Rite Products manufactures locks and latches used on commercial aircraft. We have been receiving many inquiries from mobile home builders and ambulance fabricators to supply latches that meet federal safety requirements. To date we have been unable to obtain copies of these regulations.

Please forward two copies each of the regulations governing our type of equipment. If this is not under your jurisdiction, would you please forward this letter to the proper agency or notify us of the correct address.

Robert B. Hirsch Marketing, Technical Staff

ID: nht73-5.34

DATE: 10/30/73

FROM: AUTHOR UNAVAILABLE; Robert L. Carter; NHTSA

TO: Worcester Polytechnical Institute

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of October 10, 1973, and your inquiry concerning Federal Motor Vehicle Safety Standard No. 301, and enforcement actions concerning this standard.

Standard No. 301, Fuel Tanks, Fuel Tank Filler Pipes, and Fuel Tank Connections - Passenger Cars, was effective January 1, 1968, and defined the amount of fuel leakage permissible incidental to a 30 mile-per-hour, fixed barrier collision. A copy of this standard is enclosed for your information.

Historically, this standard has not been the basis of any fines, penalties, or recalls as far as the industry is concerned; however, it has been the basis for two relatively minor, voluntary design changes within the industry.

Recently, actions have been taken to substantially upgrade Standard No. 301. An amendment to the standard published August 20, 1973 (38 F.R. 22397) expanded the standard to include all motor vehicles under 10,000 pounds, except motorcycles, cover the entire fuel system and provide a rollover provision. A Notice of Proposed Rule Making, also published August 20, 1973 (38 F.R. 22417) provided(Illegible Words) and rear impact requirements, as well as a dynamic rollover provision. Copies of these two actions are also enclosed for your information.

(Illegible Word) trust your inquiry has been satisfactorily answered. If we can(Illegible Word) of any further assisunce, pld.^&>> 8!>080>>`#S,{@0xe@ q"(td8Ev? yhRqsU89<.zq1[d`??~?~?~ <>ODY>

ID: nht90-4.79

TYPE: Interpretation-NHTSA

DATE: December 11, 1990

FROM: Robert H. Jones -- President, Triple J Enterprises, Inc.

TO: Clive Van Orden -- Office of Vehicle Safety Compliance Enforcement, NHTSA

TITLE: Re Ref O-3J005

ATTACHMT: Attached to letter dated 10-11-90 from Robert H. Jones to Congressman Ben Blaz; Also attached to letter dated 7-6-89 from Bob Jones to Congressman Ben Blas; Also attached to letter dated 7-5-90 from Robert H. Jones to Director, Office of Vehicl e Safety Compliance Enforcement, NHTSA; Also attached to letter dated 3-11-91 from Paul Jackson Rice to Robert H. Jones (A37; VSA Sec. 103(8)); Also attached to letter dated 1-22-91 from Robert H. Jones to Clive Van Orden (OCC 5733)

TEXT:

I am indebted to Congressman Ben Blaz for your name and area of responsibility.

I am enclosing some correspondence that will give you some details of our problem. In a nut shell, we want the Federal Government to enforce the FMVSS and FMCSR regulation in the CNMI or wave them completely until such time they are ready and able to im plement and enforce them.

As you may know, there are no pollution problems on Saipan, Tinian or Rota and the speed limit is 25 in most places, 35 maximum. I doubt that it is advantageous to the CNMI residents to pay the extra 3 or $400 for automobile EPA and Safety features that are not needed.

Governor Guerrero has taken a position that these regulations are not needed or desired. I agree with that position 100%. But, I have bigger problems with the regulations being, so called, applicable and not monitored or enforced.

ID: nht90-1.86

TYPE: INTERPRETATION-NHTSA

DATE: 03/27/90

FROM: LARRY F. WORT -- CHIEF BUREAU OF SAFETY PROGRAMS DIVISION OF TRAFFIC SAFETY ILLINOIS

TO: TAYLOR VINSON LEGAL COUNSEL UNITED STATES DEPARTMENT OF TRANSPORTATION

TITLE: NONE

ATTACHMT: ATTACHED TO LETTER DATED 03/27/90 FROM STEPHEN P. WOOD -- NHTSA TO LARRY F. WORT -- ILLINOIS DEPT OF TRANSPORTATION; REDBOOK A35; STANDARD 108; FORD RATIONALE FOR FMVSS 108 COMPLIANCE; BY CLARKS GORTE -- FORD; DATED 03/19/90

TEXT: The State of Illinois is requesting a legal interpretation of the federal requirements for front side marker lights on trucks. The truck model in question is a Ford low profile cab C-8000 cab over engine (see Exhibit A and B). These trucks were manufact ured with a reflex reflector at the location shown on exhibit A and do not have front side marker lights. The truck cab in question has been manufactured this way for more than 20 years.

The Division of Traffic Safety, Standard Engineer, has obtained telephone interpretations from Mr. Robert Hagan of the Bureau of Motor Carrier Safety and Mr. Kevin Cavey of the National Highway Transportation Safety Administration. Both of these gentleme n confirmed that the truck should be equipped with a front side marker light. (Exhibits A and B were telefaxed to Washington, D.C. for reference.)

Ford Motor Company has submitted a written opinion (Exhibit C) stating that they consider their vehicle to be in compliance. This information was telefaxed by Ford Motor Company to Mr. Richard Hunter in the Central Bureau of Maintenance.

A legal opinion is required on the following question of compliance (see Exhibit D);

Can the top of the cab clearance light (item six) be used to fulfill the requirements for front side marker lights (item two) on cab over engine vehicles?

ID: nht88-1.92

TYPE: INTERPRETATION-NHTSA

DATE: 04/11/88

FROM: AUTHOR UNAVAILABLE; SIGNATURE UNAVAILABLE; NHTSA

TO: Gary Hackett -- State of Nevada Taxi Cab Authority

TITLE: FMVSS INTERPRETATION

ATTACHMT: 5/10/74 letter from Lawrence R. Schneider to City of Philadelphia (Std. 206)

TEXT:

Mr. Gary Hackett State of Nevada Taxi Cab Authority Suite 200 1785 E. Square Las Vegas, NV 89155

This is in further response to your March 28, 1988, telephone conversation with Mr. Steve Wood of my staff in which you asked for an Interpretation of Federal Motor Vehicle Safety Standard No. 206, Door Locks and Door Retention Components. Your specific question asked whether Standard No. 206 requires door handles on rear doors of motor vehicles. The answer to your question is no.

The agency addressed the question you raise in a May 10, 1974, letter to Mr. Charles Murphy who asked whether manufacturers selling vehicles to the City of Philadelphia can remove the door handles from the vehicles' rear doors. In response, the agency in terpreted Standard No. 206 as not requiring an inside rear door handle. The National Highway Traffic Safety Administration stated that the standard's requirements that each passenger car rear door must have a locking mechanism that is operable from withi n the vehicle and that, when engaged, renders the outside and inside door handles inoperative (@4.1.3) specify the performance required of door locking mechanisms only. The agency thus indicated that the standard sets no requirements for inside rear door handles.

I have enclosed a copy of the Murphy letter for your information. Please feel free to contact my office if you have further questions. Sincerely,

Erika Z. Jones Chief Counsel

Enclosure - See 5/10/74 letter

ID: 8701

Mr. Richard A. Zander
AlliedSignal Automotive Proving Grounds
32104 State Road 2
New Carlisle, IN 46552

Dear Mr. Zander:

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. 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 cause 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 you 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 from 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 cause 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.

Sincerely,

John Womack Acting Chief Counsel

Enclosure

ref:105 d:3/23/94

ID: 23663Tunick_seat_bolster_DENIED_df

Mr. Lance Tunick
Vehicle Services Consulting, Inc.
P.O. Box 23078
Santa Fe, NM 87502-3078





Dear Mr. Tunick:

This responds to your letter asking three questions about the pitch, roll, and yaw requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 225, "Child Restraint Anchorage Systems" (49 CFR 571.225). I apologize for the delay in responding. We have restated your questions below, followed by our answers. As discussed, we do not agree with your suggestion that the seat cushion can be removed to meet the standard's requirements.

BACKGROUND

Standard No. 225 requires each vehicle manufactured on or after September 1, 2002, to have a child restraint anchorage system at each of two forward-facing rear designated seating positions (see S4.4(a) and (b)). The anchorage system must meet certain configuration, strength and location requirements. S15.1.2.2 of Standard No. 225 specifies use of a "child restraint fixture (CRF)" to locate the lower bars of an anchorage system. That paragraph specifies that, with the CRF attached to the anchorages and resting on the seat cushion, the bottom surface of the CRF must have attitude angles within certain limits (with angles measured relative to the vehicle horizontal, longitudinal and transverse reference planes). (Pitch must be 15 10, roll 0 5, and yaw 0 10.) Vehicles manufactured before September 1, 2004, are permitted to meet the requirements of S15 of Standard No. 225 instead of the requirements of S9. We stated in a final rule responding to petitions for reconsideration that these pitch, roll and yaw requirements will be incorporated into the requirements of S9. 65 FR 46628.

S9.3 of Standard No. 225 requires that each vehicle and each child restraint anchorage system in that vehicle shall be designed such that the CRF can be placed inside the vehicle and attached to the lower anchorages of each child restraint anchorage system, with adjustable seats adjusted in a specified manner.

You state that it is difficult to fit the CRF and/or actual child restraints in the rear seats of some sports cars. You ask about the permissibility of installing a lower anchorage beneath each rear seat cushion. You state:

The child restraint anchorage system would be used by the vehicle owner by first removing the seat bottom cushion and storing it in the vehicle's luggage compartment. The CRF, during testing, and the child seat, during real-world operation, would then be installed so as to rest stably on the metal tub (floor) of the vehicle. The location of each anchorage would be labeled as required by FMVSS 225 and the method and need of removing the seat bottom would also be labeled (the seat bottom would most probably be attached by Velcro). * * *

DISCUSSION

Question 1: Is the Proposed System permissible if removal of the seat bottom cushion is necessary in order for the CRF to fit in the vehicle and/or to meet pitch, roll and yaw criteria?

We do not interpret Standard No. 225 in a manner that would permit removal of the seat cushion. S15.1.2.2(a) of Standard No. 225 specifies that the bottom surface of the CRF shall have specified attitude angles "[w]ith the CRF attached to the anchorages and resting on the seat cushion." (Emphasis added.) Under this provision, the seat cushion is not removed when measuring attitude angles.

In addition, S9.3 of Standard No. 225 specifies that each vehicle and each child restraint anchorage system in that vehicle shall be designed such that the CRF can be placed inside the vehicle and attached to the lower anchorages of each child restraint anchorage system, with adjustable seats adjusted as described in S9.3(a) and (b). S9.3(a) and (b) state:

(a) Place adjustable seat backs in the manufacturer's nominal design riding position in the manner specified by the manufacturer; and

(b) Place adjustable seats in the full rearward and full downward position.

Neither of these provisions contemplate removing the seat cushion. Accordingly, we conclude that the seat cushion is not removed when measuring pitch, roll and yaw of the CRF. If your vehicle cannot meet the requirements with the seat cushion in place, the vehicle cannot be certified as meeting Standard No. 225.

Question 2: Is the Proposed System permissible if the CRF fits in the vehicle and meets the pitch, roll and yaw requirements with the seat bottom in place (i.e., not removed), but--

• The child seat itself, when installed, is unacceptably unstable (e.g., as regards pitch, roll, and yaw), and
• The lower anchorages must be located behind the middle of the seat back and thus potentially dangerous?

Our answer to the first part of your question is that we will evaluate the vehicle's compliance with the pitch, roll and yaw requirements using the CRF with the seat bottom in place. If all child restraints are "unacceptably unstable" despite the CRF fitting the seat, then that would suggest a design problem with the rear seat, and/or a problem with the CRF, since the device is intended to be representative of a child restraint. We would appreciate learning about any situation where the standard might permit vehicle seats and anchorage systems to be designed such that child restraints can be attached in an unacceptably unstable manner. Detailed sketches would be helpful, with vehicle dimensions included.

Our answer to the second part of this question is that an anchorage system would not be found to non-comply with the standard notwithstanding the location of the lower anchorages relative to an adult passenger's back. It should be noted, however, that you provided little information about any scenario under which the anchorages would be located "behind the middle of the seat back." With regard to passenger discomfort and safety in rear impacts, the vehicle manufacturer might want to consider using foldable or stowable anchorages, which are now permitted under Standard No. 225.

Question 3a: If the answer to either question 1 or question 2 is "no," could the vehicle manufacturer receive an exemption under S5(e)? If an exemption is available and is obtained, could the vehicle manufacturer still install the Proposed System on a voluntary basis?

S5(e) excludes certain rear designated seating positions from the requirement to provide a child restraint anchorage system at the position. To qualify for the exclusion, interference with transmission and/or suspension components must prevent the location of the lower bars of a child restraint changes system anywhere within the zone described by the standard such that the attitude angles could be met. Unless the situations described in your letter met those criteria, the exception would not be available. In response to the second part of your question, if the vehicle were excluded from the requirement to provide the lower anchorage bars because of impracticability, then by definition the bars would not be able to be installed, either voluntarily or to meet the provisions of the standard. Moreover, under S4.1 of Standard No. 225, each tether anchorage and child restraint anchorage system installed voluntarily or pursuant to the standard after September 1, 1999, must meet the configuration, location, marking and strength requirements of the standard.

Before closing, we would like to address a further issue you raised. In your letter and in other correspondence with the agency, you have expressed a belief that S9.3 is invalid because, by requiring the back seat of vehicles to fit the CRF, S9.3 allegedly violates a "no design standard prohibition." Your belief is mistaken. We seek to issue Federal motor vehicle safety standards that are performance-oriented as possible, but if need be they may have the effect of imposing certain design requirements or limitations. The CRF is representative of a child restraint system. Just as we require lap and lap and shoulder seat belt assemblies to be capable of adjustment to fit occupants whose dimensions and weight range from those of a 5^th-percentile adult female to those of a 95^th-percentile adult male (S4.1(g) of Standard No. 209, 49 CFR 571.209), we require vehicle seats to fit the CRF to ensure better compatibility and fit between vehicle seats and child restraint systems to improve the performance of child restraints in protecting children. Further, S9.3 is performance-oriented, in that manufacturers retain flexibility in designing their vehicle seats as long as they allow placement of the CRF, and the standard does not specify dimensions or other features of the vehicle seat. Accordingly, it does not create a "design standard" that would be prohibited by statute.

If you have further questions, please contact Deirdre Fujita of my staff at (202) 366-2992.

Sincerely,

Jacqueline Glassman
Chief Counsel

ref:225
d.4/25/02

ID: nht94-7.28

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.