ID: nht76-2.12

DATE: 04/14/76

FROM: AUTHOR UNAVAILABLE; S. P. Wood; NHTSA

TO: Blue Bird Body Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Blue Bird Body Company's March 15, 1976, request for confirmation that calculation of the material tensile strength of body panels under S6.2(a) of Standard No. 221, School Bus Body Joint Strength, is based on the minimum thickness permitted by American Society for Testing and Materials (ASTM) Standard 525 for the thickness specified in ordering the material. This response also reflects the April 1, 1976, meeting held between Blue Bird representatives and National Highway Traffic Safety Administration (NHTSA) personnel at Department of Transportation headquarters.

Under ASTM standards, the thickness of listed materials is permitted to vary from the specified or "nominal" thickness by a small amount. If the thickness tolerance of a material is specified by the ASTM, the NHTSA bases its determination of thickness on the "minimum thickness" specified for that material in the 1973 edition of the Annual Book of ASTM Standards. If the thickness tolerance of a material is not specified by the ASTM, the NHTSA uses the minimum thickness permitted by the school bus manufacturer's material specification.

YOURS TRULY,

BLUE BIRD BODY COMPANY

March 15, 1976

Mr. Richard B. Dyson Assistant Chief Counsel National Highway Traffic Safety Administration

SUBJECT: FMVSS 221 - SCHOOL BUS BODY JOINT STRENGTH

In S6.2(a) the subject standard makes provision for the manufacturer to determine the material tensile strength as published by the ASTM. This information is required before a manufacturer can design body joints and tooling to manufacture those joints in compliance with the subject standard.

Material tensile strength as published by the ASTM has a tolerance and we need to know to which end of the tolerance we must design. The standard adequately addresses this problem in S6.2(a) by stating ". . . .the relative tensile strength for such material is the minimum tensile strength specified for that material in the 1973 Edition of the Annual Book of ASTM Standards."

This only addresses half of the tolerance problem. The ASTM standards show tolerances for metal thickness ranges. In the absence of specific guidelines of this problem and because we must commit for tooling immediately, we are using the minimum thickness based on our specified thickness and tolerance in ASTM A525-73. This approach seems to be justified in light of the tensile strength guidelines given in S6.2(a).

If this approach is not satisfactory, please contact us by telephone immediately. We will also appreciate a written reply to this letter at your earliest convenience.

W. G. Milby Staff Engineer

cc: Bob Williams; Jim Moorman; Jim Swift

ID: nht76-2.13

DATE: 04/30/76

FROM: AUTHOR UNAVAILABLE; S. P. Wood; NHTSA

TO: Transportation Design & Technology, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your November 14, 1975, request to know how the tensile strength at a joint is determined under S6.2 of Standard No. 221, School Bus Body Joint Strength, in the case of more than two body components joined by the same fastener.

An extensive discussion of joint strength requirements and test procedures was recently sent to Blue Bird Body Company. Your question is addressed in that discussion and a copy is enclosed for your information.

YOURS TRULY,

Transportation Design & Technology, Inc.

14 November 1975

Mr. Frank A Berndt Acting Chief Counsel U.S. Department of Transportation National Highway Traffic Safety Administration

I have been asked to contact your office for a clarification of the joint integrity ruling. Where two pieces of sheet metal overlap to form a joint and are also attached to a body post of a much higher yield material, does the joint calculations apply to the surface metals only or should the higher yield material of the inner post be taken into account?

There appears to be some doubt in the minds of several people I have spoken with and therefore, I would appreciate your comments at your earliest convenience.

L. W. Smith President

ID: nht76-2.14

DATE: 02/13/76

FROM: AUTHOR UNAVAILABLE; James B. Gregory; NHTSA

TO: Hon. J. E. Moss - H.O.R.

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your January 19, 1976, letter asking for further explanation of the National Highway Traffic Safety Administration's (NHTSA) position on a school bus seating standard that specifies both passive compartmentalization and the installation of seat belt anchorages.

The NHTSA has issued its school bus seating standard (Standard No. 222, School Bus Seating and Crash Protection) in a form that requires compartmentalization of vehicle occupants but does not require installation of seat belt anchorages. There is not sufficient information in the record on which to determine what percentage of school districts would utilize seat belts. The limited evidence available to the NHTSA indicates that only a small fraction of school buses would have belts installed and properly used, and that the decision to mandate seat belt anchorage installation should await further information as to the extent to which belts would be installed and properly used.

The issue of whether the NHTSA is on "safe legal ground in mandating a requirement that in itself does not contribute to motor vehicle safety but requires further action on the part of local officials" has become less urgent in view of the standard's promulgation without anchorage requirements. I would like to respond generally that the NHTSA has always held the opinion in construing the National Traffic and Motor Vehicle Safety Act (the Act) that safety performance requirements that require further action by vehicle users are entirely appropriate. While some safety devices (such as bumpers) are in place and operate passively, most devices, (such as lights and seat belts) require occupant action to gain protection. Seat belt anchorages require more action than simple use to gain their benefits, but this does not appear to be a logally significant distinction. In this case, I decided that substantial controversy over the appropriateness and legality of this protection should not continue to create uncertainty over the ultimate form of the standard, endangering the ability of manufacturers to comply with Congress' maximum 9-month leadtime for upgrading school bus seating systems. We have, of course, left the issue of restraints in school buses.

While the decision on passive restraints could negate the value of seat belt training during the adult years, it should be noted the NHTSA is not proposing passive protection for the rear seats of passenger cars where children are encouraged to ride. They would need to use the seat belts provided to increase their protection in a crash.

SINCERELY,

CONGRESS OF THE UNITED STATES

HOUSE OF REPRESENTATIVES January 19, 1976

Dr. James B. Gregory Administrator National Highway Traffic Safety Administration

Thank you for your letter of January 13, 1976, explaining your position on mandatory seat belt anchorages for school bus seats.

Protecting children who ride school buses from the risk of injury is a critical need, well established by the passage of the Motor Vehicle and Schoolbus Safety Amendments of 1974. I would agree that a zero fatalities/zero injuries record is a reasonable goal for school bus safety. Moreover, a properly conceived seat belt system for school bus seats could potentially offer a high level of protection to the young occupants using them. At the same time, I am compelled to address further questions to you regarding the proposal to require seat belt anchorages alone.

I understand clearly that the idea of requiring seat belt anchorages is to facilitate efforts on the part of local school districts deciding to install belt restraints in new school buses they buy. Moreover, it is clear that if a seat belt system ever becomes mandatory in new buses, the existence of anchorages in older buses will aid school districts deciding to bring buses they already own up to the standard by retrofitting belts into their existing fleet. Finally, I can see the wisdom of seat belts in school buses for training purposes, if we continue to mandate active restraint systems in passenger vehicles generally. Nonetheless, several questions concern me.

(1) Do you believe NHTSA to be on safe legal ground in mandating a requirement that in itself does not contribute to motor vehicle safety but requires further action on the part of local officials -- namely, having belts installed before the added safety feature becomes available for children to use?

(2) Is there evidence in the record of the rulemaking that school districts intend to exercise their option to have belt systems installed once the anchorages become available? If not, how is it possible to justify even the minor cost of this requirement given the absence of any projected benefits?

(3) Regarding the educational value of belt use in school buses, won't the need for this training decline over the next few years if passive restraints are mandatory for new passenger vehicles and gradually introduced into the vehicle population as new cars replace old ones?

I support entirely the "passive protection" approach reflected in the balance of the proposed standard as far as it goes and believe it will offer substantial additional protection to children riding buses. This approach makes particular sense if NHTSA decides to mandate passive restraints in all new passenger vehicles.

On the other hand, if active restraints -- in particular seat belt systems -- continue to be required for the general vehicle population, then it makes sense in school buses to mandate not just anchorages but appropriate and usable belt systems. An appropriate system is one that uses retractors so that belts are self-adjusting in use and stay clean when not in use; that has buckles located in or near the seat fold so that the heavy part of the buckle cannot be wielded in horseplay; and one that will target the child's head against a safe surface if the bus abruptly comes to a halt or crashes.

In short, if we are to protect the integrity of the NHTSA regulatory program, then we should be hesitant to introduce requirements such as this, which offer extremely marginal benefits at best, even by the most favorable analysis.

I have further questions relating to this rulemaking -- particularly whether it adequately meets the mandate established by the Congress in the 1974 Amendments. These questions are perhaps more substantial than the anchorage issue; however, the sufficiency of the balance of the standard is a question I will reserve for the Subcommittee's oversight hearing on NHTSA tentatively scheduled for February 6, 1976.

Thank you for your attention to the questions this letter raises.

JOHN E. MOSS Chairman Oversight and Investigations Subcommittee

ID: nht76-2.15

DATE: 11/10/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Thomas Built Buses, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of September 2, 1976, in which you ask whether the definition of "Contactable surface" in Standard No. 222, School Bus Passenger Seating and Crash Protection, includes areas on the front of the seatback located more than three inches from the top of the seat.

Your interpretation of "contactable surface" is correct. The standard states in paragraph S4 that only the uppermost three inches of area on the front of the seatback is considered part of the "contactable surface." The remainder of the front of the seatback is not considered part of the "contactable surface" and need not meet the head impact requirements of S5.3.

SINCERELY,

Thomas BUILT BUSES, INC.

September 2, 1976

Tim Hoyt National Highway Traffic Safety Administration U. S. Department of Transportation

Enclosed are two (2) prints that show our interpretation of the MVSS #222 seat impact regions. In a previous letter, we were informed that the head impact region (marked "H") extends downward to the "12 inch level" above the S R P on the aisle of the seat. The front of the seat was not mentioned.

Our interpretation of S 4. definitions.

"Contactable Surface" is that we do not need to meet the head impace requirements on the front of the seatback below the "H" region. This region is shaded and dimensioned 3" on the print. Is this interpretation correct?

Thanking you in advance for your services, we remain,

L. T. Mitchell, Jr. Engineering Department

H - HEAD IMPACT REGION

K - KNEE IMPACT REGION

(Graphics omitted)

H - HEAD IMPACT REGION

K - KNEE IMPACT REGION (Graphics omitted)

ID: nht76-2.16

DATE: 07/30/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Thomas Built Buses, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Thomas Built Buses' June 4, 1976, question whether the requirements in S5.1.3 and S5.1.4 of Standard No. 222, School Bus Seating and Crash Protection, to "Apply additional force . . . through the . . . loading bar until (a specified number) of inch-pounds of energy has been absorbed in deflecting the seat back . . ." can be satisfied in part by the energy that is returned to the load bar as it is withdrawn from the seat back. You also ask if there are minimum or maximum time limits on withdrawal of the loading bar from the seat surface.

The requirement for the absorption of a minimum amount of energy in (Illegible Word) the seat back in the forward and rearward directions is calculated to provide adequate measurement of the energy involved in the impact between the bus occupants and the seating in a percentage of school bus crashes. The agency calculated the amount of energy to be consumed by the seat back that would result in adequate protection. The specification requires the seat to "absorb" (i.e., receive without recoil) a specific amount of energy. This value is represented by the amount of energy that is not returned to the loading bar as it is withdrawn. Described graphically, the area that represents returned energy under the seat back force/deflection curve must be subtracted from the entire area that lies under the curve in order to calculate the energy "absorbed" by the seat back.

With regard to your second question, no time limits have been established for withdrawal of the loading bar. The agency intends to utilize a withdrawal time that is not more than five minutes so that creep will not be a significant factor in determining energy absorption. Because the time is not specified, the manufacturer is free to use any reasonable time that does not significantly affect the elastic and plastic components of the seat back loading.

thomas BUILT BUSES, INC.

June 4, 1976

Mr. Bob Krause Office of Standards Enforcement Motor Vehicle Programs U.S. Dept. of Transportation National Highway Traffic Administration

Re: Part 571 - Federal Motor Vehicle Safety Standards - Para. 571.222 S5.1.4.1 & S5.1.4.2

Our engineering department is in the process of developing testing and analysis techniques for demonstration of compliance with the referenced section of FMVSS. To ensure that these techniques will meet all requirements, we are in need of further clarification of the paragraphs pertaining to seat back load application. Accordingly, we would appreciate answers from your department on the following specific questions:

(1) Para. 571.222 S5.1.4.2 specifies energy absorption of the seat back deflection during load application. What is the significance of or treatment required of the energy returned during the backing off of the loading bar?

(2) Are there any requirements regarding elapsed time interval for the load back-off?

(3) Same questions re Para. 571.222 S5.1.3 thru S5.1.3.4 - Seat Performance Forward.

Thank you for your prompt assistance in answering these questions.

Malcolm B. Mathieson Engineering Manager

ID: nht76-2.17

DATE: 12/14/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: School Bus Manufacturers Institute

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of November 2, 1976, in which you ask for an interpretation of the term "absorbed" as it is used in Standard No. 222, School Bus Passenger Seating and Crash Protection. Further, you request that the NHTSA withdraw its earlier interpretation of the same term made on July 30, 1976, to Thomas Built Buses.

In your letter, you outline data showing that a seat may meet the energy absorbtion requirements of S5.1.3 when recoil energy is included, while failing those same requirements when recoil energy is subtracted from the total energy. You further argue that the NHTSA interpretation of July 30, 1976, which explained the subtraction of recoil energy, is at variance with the wording of the standard, because the standard does not explicitly require the subtraction of recoil energy and speaks only to the application of force upon the seat. Moreover, you suggest that plotting the recoil energy results in insufficient area under the force/deflection curve to meet S5.1.3. For these reasons, you request that the term "absorbed" be defined as the total energy received by the seat without subtracting energy that is returned through recoil.

The NHTSA declines to adopt the interpretation that you suggest. The dictionary definition of the term "absorbed" is "to receive without recoil." This definition, when applied to energy absorbed by a seat, contemplates the subtraction of recoil energy in the computation of absorbed energy. The NHTSA intentionally chose the term "absorbed" to denote exactly this meaning. Therefore, according to the common usage of the term "absorbed," the standard does require the subtraction of recoil energy even though those express words are never used.

Your assertion that plotting the recoil energy results in a force/deflection curve that falls within the prohibited zones indicates a misunderstanding of the force/deflection zone requirements. The force deflection zone requirements (S5.1.3(a), S5.1.3(b), S5.1.4(a), and S5.1.4(b)) prescribe limits within which the seats must perform only during the force application phase of the test procedure.

SINCERELY,

SCHOOL BUS MANUFACTURERS INSTITUTE

November 2, 1976

Frank A. Berndt Office of Chief Counsel National Highway Traffic Safety Administration

On July 30, 1976, the National Highway Traffic Safety Administration issued an interpretation to Thomas Built Buses, Inc. (Item 1) defining the term "energy absorbed in deflecting the seat back" as it relates to the new FMVSS 222 School Bus Passenger Seating (Item 2). The Agency's definition of this term is based on the concept that the absorbed energy equals the amount of energy received less the energy associated with recoil.

The School Bus Manufacturers Institute representing the six major manufacturers of school buses takes exception to this terminology being applied to the present configuration of FMVSS 222. We do not disagree with the semantics but we do believe that there is a definite conflict between the definitions interpretation and the test procedures outlined within the standard.

Our disagreement is not just a recent development. As early as September 1974 through discussions with National Highway Traffic Safety Administration Legal and Engineering, the SBMI indicated that a seat demonstrating purely elastic properties could be constructed to meet the then proposed FMVSS 222.

On a number of occasions since that time, this question has been reviewed by National Highway Traffic Safety Administration personnel. Nevertheless, on January 22, 1976, the final draft of FMVSS 222 was issued without any reference to rebound or recoil adjustments to the test procedure.

Based on the FMVSS 222 test criteria, the SBMI members have designed, developed and tested an entirely new generation of school bus seats. The Thomas Interpretation drastically changes the test criteria used in compliance calculation.

FMVSS 222 Section S5.1.3 states:

Seat performance forward. When a school bus passenger seat that has another seat behind it is subjected to the application of force as specified in S5.1.3.1 and S5.1.3.2 and subsequently, the application of additional force to the seat back as specified in S.5.1.3.3 and S5.1.3.4:

(a) The seat back force/deflection curve shall fall within the zone specified in Figure 1;

(b) Seat back deflection shall not exceed 14 inches; (for determination of (a) and (b) the force/deflection curve describes only the force applied through the upper loading bar, and only the forward travel of the pivot attachment point of the upper loading bar, measured from the point at which the initial application of 10 pounds of force is attained.)

(c) The seat shall not deflect by an amount such that any part of the seat moves to within 4 inches of any part of another school bus passenger seat or restraining barrier in its originally installed position;

(d) The seat shall not separate from the vehicle at any attachment point; and

(e) Seat components shall not separate at any attachment point.

In order that we may more clearly define our objection to the Thomas Interpretation, a typical force/deflection seat test is enclosed (Item 3).

The shaded areas above and below the acceptable zone indicate a seat that is too rigid (upper shaded zone) or too limber (lower shaded zone) to manage the accident induced impacts. Therefore, the force/deflection characteristics properly designed seat will fall within the unshaded area.

Line A plotted on the force deflection curve (Item 3) indicates the amount of seat back deflection for a given loading.

Prior to the Thomas Interpretation line A would be a satisfactory test.

S5.1.3

(a) The curve fell within the specified zone

(b) The seat back deflection did not exceed 14"

(c) The seat did not encroach to within 4" of an adjacent seat

(d) The seat did not separate from the vehicle

(e) The seat components did not separate

The area below line A was above the minimums set by the National Highway Traffic Safety Administration.

Should the Thomas Interpretation be applied to this same seat test, the results are entirely different (Item 4). The new interpretation will require that the recoil of the seat after testing be measured and plotted on the graph-line B.

S5.1.3

(a) The curve fell within the shaded area

The area included within lines "A" and "B" is less than the limit allowed by the National Highway Traffic Safety Administration.

This example outlines one area of conflict between FMVSS 222 and the Thomas Interpretation. FMVSS 222 makes no mention of measuring and plotting rebound, as a matter of fact the test criteria requires only forward motion of the loading bar during the forward test and rearward motion during the rearward test.

The SMBI is now to the point of product verification based on the final draft of FMVSS 222. To revise the test levels at this late date will place an unjust economic burden on this industry.

If it is the Agency's intention to have school bus seats that "eat up" a given amount of energy during a crash, then this requirement should be spelled out within the standard and not within a private interpretation.

Because of the wide reaching effects of this interpretation, we ask that the National Highway Traffic Safety Administration withdraw the Thomas Interpretation and in its place introduce a proposal to revise FMVSS 222 to include the Agency's definition of energy absorption.

If we can be of any assistance in clarifying this matter please feel free to contact me.

Byron A. Crampton Manager of Engineering Services

ITEM 2

(Illegible Line) and Crash Protection FMVSS 222 Effective April 1, 1977

(Regulation Omitted)

ID: nht76-2.18

DATE: 11/15/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Gillig Bros.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of September 13, 1976, in which you ask whether Standard No. 222, School Bus Passenger Seating and Crash Protection, requires that the 20-inch maximum separation between the seating reference point and the rear surface of the restraining barrier be measured at the point of greatest distance between the two.

The restraining barrier you describe has padded tubing around its circumference which would be closer to the seating reference point than the center section of the barrier. The National Highway Traffic Safety Administration (NHTSA) interprets the requirements of paragraph S5.2.1 of Standard No. 222 to mean that the 20-inch distance must be measured from the seating reference point to the surface of the seat back or restraining barrier, exclusive of portions which protrude from the basic contour of the surface. The side tube portion would constitute such a protrusion.

SINCERELY,

September 13, 1976

Thomas W. Herlihy Office of Chief Counsel National Highway Traffic Safety Administration

We have a question relative to School Bus Safety Standard Number 222. The standard states "that there shall not be more than 20" from the seating reference point to the rear surface of the restraining barrier". This distance being measured along a horizontal longitudinal line through the S.R.P in the forward direction.

Our question is this: What is considered the rear surface. Is it part furthest to the rear, which in our case would be the padding on the side tube portion of our seat frame? Or is it considered to be the rear padding on the sheet metal center section of the seat?

Attached is a sketch which we hope will clarify our question.

As our new seat spacing design requirements hinge on your answer, we would appreciate your written answer as early as possible.

Lewis C. Coffey Chief Engineer

cc: TIMOTHY HOYT -- OFC. OF CRASHWORTHINESS

(Graphics omitted) (Graphics omitted)

ID: nht76-2.19

DATE: 11/22/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Crown Coach Corp.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your letter of October 7, 1976, in which you ask several questions concerning Standard No. 217 Bus Window Retention and Release, and Standard No. 222, School Bus Passenger Seating and Crash Protection.

Your first question asks whether a California regulation requiring 20-inch minimum seat spacing in school buses would be preempted by the requirement for 20-inch maximum seat spacing in Standard No. 222.

The National Traffic and Motor Vehicle Safety Act (the Act) provides in section 103(d) that any state or local law or regulation on an aspect of motor vehicle performance covered by a Federal standard must be identical to that Federal standard. Although the NHTSA requirement is phrased in terms of maximum spacing while the California standard concerns minimum spacing, the aspect of performance in question is seat spacing. Therefore, it is the NHTSA's opinion that a California standard on seat spacing regulates the same aspect of performance and to the degree it is not identical to the Federal standard, it would be preempted.

Your second question asks whether the seating reference point, as specified in relation to the "H" Point used in SAE Standard J826b, varies with the size of different individuals. The seating reference point, as defined by the NHTSA in Part 571.3 allows the manufacturer some discretion in selecting a point that approximates the position of the pivot center of the human torso and the thigh. While the NHTSA definition does refer to the SAE procedures for "H" point location that includes the specific measurements you cite, the manufacturer retains discretion to vary this point slightly as long as he can show that the point selected continues to simulate the position of the pivot center of the human torso and the thigh of the passengers for whom the seat is designed.

Finally, you note in your letter that compliance with the seat spacing required in Standard No. 222 might entail relocation of the side emergency exit, because Standard No. 217 requires that "[a] vertical transverse plane tangent to the rearmost point of a seat back shall pass through the forward edge of a side emergency door." The seat spacing requirement arguably could occasion the realignment of the side emergency door, but this does not have to be the case. The manufacturer is free to adjust seat spacing to be properly aligned with the emergency exit. The NHTSA's intent in this requirement is to provide an emergency exit opening extending at least 2 feet rearward of a vertical transverse plane tangent to the rearmost point of a seat back. The agency would not prohibit the use of doors wider than 2 feet as long as a minimum 2-foot opening is provided rearward of the reference plane and the latch mechanism is operated by a device located within the required 2-foot opening.

SINCERELY, Crown COACH CORPORATION

October 7, 1976

National Highway Traffic Safety Administration Motor Vehicle Programs Office of Chief Council

SUBJECT: Federal Standard 222-School Bus Seating and Crash Protection

We are presently trying to establish a seating floor plan to conform to your standards. So far, we know of only one manufacturer that may produce a seat meeting your requirements, namely American Seating Company.

The point in question is the establishment of some manufacturing tolerance between seats. Standard 222 states the maximum spacing from the seats, Seating Reference Point (SAE "H" Point), is 20 inches. This distance is equal to the minimum California standard of 25 inches from seat back to the back of the seat in front. This would leave no manufacturing tolerance. We know that Federal Standards take precedence, but the State could put a limitation on minimum spacing. American Seating has told us that they are using 20 inches +/- 1/2 inch. as a target. They will also have a tolerance on the thickness of their seat, which would affect seat spacing.

Another question on the "H" Point as specified in SAE Standard J826 - the distance up from the seat to the "H" Point is 3.84 Inches and from the "H" Point to the seat back is 5.28 Inches. Would not these dimensions change with respect to different percentile figures?

The location of the seats and tolerances create another problem which cannot be solved until something has been firmed up; that is, the location of the side emergency exit.

Standard 217, Docket No. 75-3, Notice 4, states "A vertical transverse plane tanget to the rearmost point of a seat back shall pass through the forward edge of a side emergency door." This means the door has to float with the seat locations. Also suppose the door is larger in size than the Standard states, this would penalize the manufacturer of the bus body, having to redesign side walls to accept different door and window locations.

We have been in contact with Mr. Tim Hoyt of your Docket Writer Section, who has been very helpful, but cannot answer our specific questions, and recommends we contact your Department for clarification of the Standard and specific answers to our problems.

If you need any clarification on our questions please phone and we will try to explain more fully.

Ray Hartman Vice President-Engineering

ID: nht76-2.2

DATE: 09/03/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Nissan Motor Co., Ltd.

TITLE: FMVSS INTERPRETATION

TEXT: This is in response to your January 26, 1976, question whether Standard No. 124, Accelerator Control Devices, requires that the throttle return to the "idle position" within specified time limits in the case where an "automatic speed control device" is in operation and a failure occurs in it.

The requirements of S5.1 and S5.2 of the standard require a return of the throttle to the idle position when either one source of throttle "return energy" or a component of the accelerator control system fails or is disconnected. In the case you describe, failure does not occur as outlined in S5.1 and S5.2. Therefore, this failure is not regulated by the standard. This is the case, because the NHTSA does not consider throttle-setting devices to be a component that "[regulates] engine speed in direct response to movement of the driver-operated control and that [returns] the throttle to the idle position upon release of the actuating force" as defined in S4.1. As set out in the definition of "idle position", the agency considers the effect of a throttle-setting device to be a separate condition that affects the setting of the accelerator control system.

YOURS TRULY,

NISSAN MOTOR CO., LTD.

January 26, 1976

Frank Berndt Office of Chief Council National Highway Traffic Safety Administration

This is to ask your interpretation regarding the requirement of FMVSS 124 for automatic speed control system.

NHTSA stated in the preamble of Docket No. 69-20; Notice 3 published on April 8, 1972, "the rule does not contain requirements for automatic speed control devices . . .".

Does it mean that FMVSS 124 does not apply to automatic speed control system itself? In other words, may we understand that while the vehicle is travelling by actuating automatic speed control system, the throttle need not return to the idle position within the time limit specified in S.5 of FMVSS 124 even if some failures occur in the devices of automatic speed control system?

Thank you for your attention to the above question. We look forward to hearing your interpretation of the above in the near future.

Tokio Iinuma Staff, Safety

ID: nht76-2.20

DATE: 07/20/76

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: General Motors Corporation

TITLE: FMVSS INTERPRETATION

TEXT:

July 20, 1976 N40-30

Mr. David E. Martin, Director Automotive Safety Engineering Environmental Activites Staff General Motors Corporation Warren, Michigan 48093

Dear Mr. Martin:

It has come to the attention of the National Highway Traffic Safety Administration that General Motors Corporation is planning to include in its 1977 Cadillac incomplete vehicle document the following statement with respect to Federal Motor Vehicle Safety Standard No. 301-75, Fuel System Integrity:

Conformity with FMVSS 301 is not subtantially determined by the design of this incomplete vehicle and General Motors makes no representation as to conformity with this Standard.

The use of this statement would not comply with 49 CFR Part 568, Vehicles Manufactured in Two or More Stages.

A copy of the March 8, 1976, letter from Mr. W. J. Owen of the Cadillac Motor Car Division to Mr. R. B. Kurre of the Wayne Corporation is attached for your reference. That letter was included in the petition of Wayne's Miller-Meteor Division for a temporary exemption from Standard No. 301-75 as applied to the ambulances and funeral coaches that Wayne manufactures using Cadillac commercial chassis.

I understand that these chassis are delivered to Wayne with the fuel system components already installed, that Wayne removes certain components in order to mount the body, and that those components are reinstalled after the mounting of the body.

The incomplete vehicle document is required by S568.4(a)(7) to include a--

listing by number of each standard...followed in each case by one of the following three types of statement, as applicable:

(i) A statement that the vehicle when completed will conform to the standard if no alterations are made in identified components of the incomplete vehicle....

(ii) A statement of specific conditions of final manufacture under which the manufacturer specifies that the completed vehicle will conform to the standard.

(iii) A statement that conformity with the standard. is not substantially determined by the design of the incomplete vehicle, and that the incomplete vehicle manufacturer makes no representation as to conformity with the standard.

There is a factual limitation on use of the third statement. It may not be used for standards conformity to which is substantially determined by the design of the incomplete vehicle. Where the basic fuel system components, including fuel tank and lines and filler pipe, are included in the incomplete vehicle, compliance of the completed vehicle with Standard N0.301-75 is substantially determined by both the design of the incomplete vehicle and the manner of completion by the final stage manufacturer. Therefore, General Motors is required to include a statement of the first or second type with respect to Standard No. 301-75 in the incomplete vehicle documents accompanying Cadillac commercial chassis that are manufactured on or after September 1, 1976, add designed for completion into multipurpose passenger vehicles. Such chassis that are manufactured before that date are not required by Part 568 to include any statement concerning Standard No. 301-75, because there are no fuel system integrity requirements for multipurpose passenger vehicles until that date.

The above discussion also applies to any other commmercial chassis manufactured by General Motors for sale as incomplete vehicles.

Yours truly,

Frank Berndt Acting Chief Counsel

Enclosure

March 8, 1976

Mr. R. B. Kurre Wayne Corporation Industrial Road Richmond, Indiana Dear Mr. Kurre:

Confirming our phone conversation, the following statement will be used relating to FMVSS 301 Fuel System Integrity in the 1977 Cadillac Document for Incomplete Vehicle as required by Part 568-Vehicles Manufactured in Two or More Stages:

Conformity with FMVSS 301 is not substantially determined by the design of this incomplete vehicle and General Motors makes no representation as to conformity with this Standard.

Please let us know if we can help you further.

Very truly yours,

W. J. Owen Safety and Legal

-ajj

cc: Messrs. E. W. Anderson A. MacDonald