ID: nht78-1.33

DATE: 03/22/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Blue Bird Body Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your January 11, 1978, letter asking whether several joints in your school bus must comply with Standard No. 221, School Bus Body Joint Strength.

The terms which establish the applicability of the requirements of the standard to a particular section of a school bus body are defined in S4 of the standard. Read together they establish the following test. If the edge of a surface component (made of homogeneous material) that encloses occupant space in a bus comes into contact or close proximity with any other body component, the requirements of S5 apply, unless the area in question is designed for ventilation or another functional purpose, or is a door, window, or maintenance access panel. Applying this test to the several joints to which you refer, it appears that they do not need to comply with the requirements since they connect panels which are considered to be maintenance access panels.

The National Highway Traffic Safety Administration (NHTSA) notes that maintenance access panels are granted this exception from the requirements because of their need for removal for routine service to underlying components. The NHTSA will not consider all bus walls as maintenance access panels simply because wiring may be present behind them since routine maintenance would not be required on such wiring. Further, should any of the panels to which you refer in your letter not have wiring or other serviceable components requiring routine maintenance behind them, they will not be treated as maintenance access panels.

SINCERELY,

January 11, 1978

Joseph J, Levin, Jr. Chief Counsel National Highway Traffic Safety Administration

Dear Mr. Levin:

SUBJECT: 571.221 Standard Number 221, School Bus Body Joint Strength

Section S4 defines a body panel joint as follows:

""Body panel joint" means the area of contact or close proximity between the edges of a body panel and another body component, excluding spaces designed for ventilation or another functional purpose, and excluding doors, windows, and maintenance access panels." Blue Bird has initially set up the following panels to meet 60% joint strength per S5.

Front Upper Inner Panel

Rear Upper Inner Panel

Rear Vision Panel Inside Right Hand

Rear Vision Panel Inside Left Hand

Rear Inner Panel Right Hand

Rear Inner Panel Left Hand

Post Cap Rear Emergency Door Access Right Hand

Post Cap Rear Emergency Door Access Left Hand

We have had field and production line complaints regarding wiring access with the many rivets in these panels and propose to designate these panels as maintenance access panels per section S4 and install them with screws as shown in the enclosed pictures. Sheets 1 through 5 show the lamp wiring which is serviced by the appropriate inside panels.

We understand that competitive make buses are already using similar designs and we are being pressured by the marketplace from both the cost and serviceability points of view to adopt the proposals which appear in this letter.

We look forward to receiving your confirmation that these proposals fully comply with the requirements of FMVSS 221.

W. G. Milby Manager, Engineering Services

[ENCLS. OMITTED]

ID: nht78-1.34

DATE: 01/25/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Blue Bird Body Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your October 24, 1977, letter asking whether the framework of a roof hatch must comply with the requirements of Standard No. 221, School Bus Body Joint Strength.

The terms which establish the applicability of the requirements of the standard to a particular section of school bus body are defined in S4 of the standard. Read together they establish the following test. If the edge of a surface component (made of homogeneous material) that encloses occupant space in a bus comes into contact or close proximity with any other body component, the requirements of S5 apply, unless the area in question is designed for ventilation or another functional purpose, or is a door, window, or maintenance access panel. Applying this test to the frame of a roof hatch, it appears that this joint need not comply with the requirements. This conclusion is reached because the National Highway Traffic Safety Administration concludes that a roof hatch is equivalent to a door or window for the purposes of the application of the requirements. The joint connecting the frame of a door, window, or roof hatch to a bus body falls within the exception to the applicability of Standard No. 221.

SINCERELY,

BLUE BIRD BODY COMPANY

October 24, 1977

Joseph J. Levin, Jr. Chief Counsel National Highway Traffic Safety Administration

Dear Mr. Levin:

The purpose of this letter is to get an interpretation regarding the applicability of FMVSS 221 relative to roof hatch emergency exit components.

The attached photos show a roof hatch viewed from inside the bus and from the roof of the bus. We would like confirmation of our interpretation that the metal framework of the roof hatch opening, shown in the attached photos, enclosing the edges of the roof opening are for a "functional purpose" as used in FMVSS 221, paragraph S4 and are, therefore, not subject to the requirements of that standard.

We will appreciate your early reply.

Thank you.

W. G. Milby Manager, Engineering Services

CC: JIM MOORMAN; JIM SWIFT; GARY MOYSES; TOM TURNER

(Graphics omitted)

ID: nht78-1.35

DATE: 05/11/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Dr. Arthur Yeager

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your telephone request of March 24, 1978, asking whether the seats in school buses are sufficiently strong to allow the installation of seat belts. You stated that some manufacturers are indicating that they cannot install seat belts because the floors of larger school buses cannot withstand the forces generated by seat belts.

As you indicated, Notice 5 of Docket 73-3 stated that school bus seats should be strong enough to withstand the forces seat belts would impose upon them. This statement was based upon the fact that the seats would be designed to comply with the other force requirements of the standard which would increase the strength of the seats making them capable of withstanding seat belt loads. At the time of that notice, there were special seat belt requirements for seat belts in school buses in the then proposed Standard No. 222. These seat belt requirements would have mandated lower belt load requirements than those found in Standard No. 210 which currently applies to school buses (under 10,000 pounds GVWR). The seats in larger school buses should be sufficiently strong to withstand the former proposed force requirements of Standard No. 222, but they might be incapable of withstanding the belt load requirements of Standard No. 210.

Manufacturers who indicate that the seats or floors of larger buses are not strong enough to install seat belts probably misunderstood the belt requirements for large buses. Seat belts can be installed for passenger seats in larger school buses without complying with any existing seat belt requirements. Seat belts for passenger seats are not required, for example, to comply with Standard No. 210. Therefore, a State would be permitted to establish their own acceptable belt load requirements for these seat belts in large school buses. The National Highway Traffic Safety Administration suggests that States adopt the belt load requirements previously proposed for Standard No. 222. School bus seats currently in production should be sufficiently strong to withstand the former proposed belt load requirements.

ID: nht78-1.36

DATE: 05/11/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Blue Bird Body Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your February 9, 1978, letter asking how to measure the head form contact area in Standard No. 222, School Bus Passenger Seating and Crash Protection.

In your first paragraph, you indicate that the National Highway Traffic Safety Administration (NHTSA) has allowed the knee form contact area measurement to be undertaken on or within a line 1 1/2 inches from the edge of the leg protection zone to ensure that the knee form will contact the entire surface. You ask that a similar line be established for the head protection zone contact areas.

As you know, the head form contact area requirements apply to more areas than do the knee form contact area requirements. The knee form contact area requirements apply only to seat backs and the backs of restraining barriers. The head form contact area, on the other hand, includes anything falling within a specified zone which might include the sides or tops of seats. Therefore, it is impossible to create fictional lines around the outer edges of objects that fall within the head protection zone for purposes of testing the compliance of those objects with the requirements. The agency notes further that it never stated that it would test knee form contact area on or inside a line 1 1/2 inches from the edge of a seat back or restraining barrier. The agency did state that it would test in a manner that "provides opportunity for the knee form to contact with the seat back or restraining barrier to the fullest extent possible." That interpretation can also be applied to the head form contact area requirements.

SINCERELY,

BLUE BIRD BODY COMPANY

February 9, 1978

Joseph J. Levin Chief Counsel National Highway Traffic Safety Administration

Dear Mr. Levin:

Reference: 1. W. G. Milby to Frank Berndt, December 20, 1976 2. Frank Berndt to W. G. Milby, February 23, 1977, N 40-30

Reference number 1 requests an interpretation that the centerline of the knee impact tests of FMVSS 222 only be required on or inside of a line 1 1/2" (same as knee form radius) from the edge of the leg protection zone. The reason for the request was to insure that it is physically possible to obtain the required contact area and to insure that enough padding of the correct composition is available for the knee form to contact.

Reference number 2 grants the request of reference number 1.

The purpose of this letter is to confirm our assumption that the same reasoning should be applicable to the head protection zone.

Thank you for your early response.

W. G. Milby Manager, Engineering Services

ID: nht78-1.37

DATE: 01/26/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Sheller-Globe Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your December 6, 1977, letter asking which portions of the roof and sidewall structure of your small bus must comply with the head impact requirements of Standard No. 222, School Bus Passenger Seating and Crash Protection.

In accordance with the head impact zone requirements outlined in paragraph S5.3.1.1 of the standard, the National Highway Traffic Safety Administration has determined that those portions of your bus constituting the bus sidewall and window structure are not required to comply with the head impact requirements. Only those portions of your bus which constitute part of the roof structure are included within the head impact zone requirements. We have marked in yellow on the enclosed drawing those areas that must comply with the head impact requirements.

SINCERELY,

SHELLER-GLOBE CORPORATION Vehicle Planning and Development Center

December 6, 1977

National Highway Traffic Safety Administration

Attention: Chief Counsel, Frank A. Berndt

Gentlemen:

Reference is made to S.5.3.1.1. of FMVSS 222 - School Bus Seating and Crash Protection, which states the bus sidewall, window, or door structure are not included in the impact zone.

Our question is, what all do you consider as window structure and if a side body pillar and the structure over the top of the window assembly to which the window is mounted, are also not included in the impact zone? The pillar and structure in question are marked in red for the Dodge and blue for a Chevrolet on drawing #K-4300021.

It would be appreciated if you would indicate on the extra copy of the drawing area needing or not needing to be included in the impact zone.

R. M. Premo - Director Vehicle Safety Activities

ID: nht78-1.38

DATE: 04/25/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Wayne Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your February 28, 1978, letter asking whether portions of your van-type school bus have to comply with the head protection zone requirements of Standard No. 222, School Bus Passenger Seating and Crash Protection. You enclosed pictures showing portions of the bus designated in pink and yellow and question the standard's applicability to them.

The head protection zone requirements do not apply to portions of the school bus that are considered part of the bus sidewall. The National Highway Traffic Safety Administration considers the sidewall to include those surfaces that run parallel to the outboard edge of a forward facing seat. Accordingly, the portions of your bus designated in yellow in the pictures need not comply with the requirements since they are part of the bus sidewall structure. The pink portions of your photographs represent part of the bus structure that is perpendicular to the bus sidewall. The NHTSA does not consider them to be part of the bus sidewall structure. Therefore, since they fall within the head protection zone they must comply with all of the requirements applicable to that zone.

Sincerely,

ATTACH.

PHOTO A VIEW LOOKING FORWARD TOWARD RIGHT-HAND FRONT SERVICE DOOR.

(Graphics omitted)

PHOTO B VIEW LOOKING FORWARD TOWARD LEFT-HAND FRONT DRIVER'S AREA.

(Graphics omitted)

Wayne Corporation

February 28, 1978

Office of Chief Counsel National Highway Traffic Safety Administration

Dear Sir:

This inquiry concerns Federal Motor Vehicle Safety Standard 222, School Bus Passenger Seating and Crash Protection. The enclosed photographs marked and labeled as follows:

Photo A - View looking forward toward right-hand front service door, and Photo B - View looking forward toward left-hand front driver's area, show interior views of the Wayne Busette school bus described in the enclosed Wayne Busette specification sheet. The interior surfaces of the bus colored pink and yellow in Photos A and B fall within the head protection zone defined in FMVSS 222, S5.3.1.1. For purposes of clarity, the front row of passenger seats had been removed before the pictures were taken.

Please advise whether or not the areas colored pink and yellow in Photos A and B are subject to the requirements of FMVSS 222, S5.3.1.2, Head Form Impact Requirements, and S.5.3.1.3, Head Form Force Distribution. In responding to this inquiry, we ask that consideration be given to the first paragraph of S5.3.1.1, "The head protection zones in each vehicle are the spaces in front of each school bus passenger seat which are not occupied by bus sidewall, window, or door structure and which . . . ." Wayne believes that while the pink and yellow colored areas are located in front of a passenger seat, these surfaces should be classified as part of the bus sidewall, window, and door structure and, therefore, are excluded from the requirements of S5.3.1.2 and S5.3.1.3.

Your prompt attention and early reply to this inquiry would be greatly appreciated.

Sincerely yours,

Robert B. Kurre Director of Engineering

[Enclosures Omitted]

ID: nht78-1.39

DATE: 06/16/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Blue Bird Body Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your April 24, 1978, letter asking two questions concerning Standard No. 222, School Bus Passenger Seating and Crash Protection.

In your first question, you ask what the National Highway Traffic Safety Administration (NHTSA) means by the phrase "seat components shall not separate at any attachment point." This phrase is found in the forward and rearward loading performance tests. You suggest that the NHTSA interpret this to mean a complete separation of a seat component from another component. The NHTSA disagrees with this suggestion.

The standard as written clearly indicates that the agency has intended that seat components remain connected at all attachment points during testing. If the agency had intended a complete separation of seating components to be the test for separation, it would have used that language in the drafting of the regulation. Therefore, the agency declines to adopt the interpretation that you suggest and will require the seat to remain attached at all attachment points during testing.

Your second suggestion concerns a possible problem in the computation of loads during rearward testing. You state that occasionally the loading bar will become buried in the upholstery material and, therefore, distort the actual seat loads. The NHTSA has not noted the phenomenon to which you refer. However, if it were to occur in compliance testing the agency would be certain to factor out any aberrations in the test results that occurred owing to this loading bar problem.

SINCERELY,

April 24, 1978

Joseph J. Levin Chief Counsel National Highway Traffic Safety Administration

Dear Mr. Levin:

The purpose of this letter is to seek a clarifying interpretation on two issues relating to FMVSS 222.

1. S 5.1.3 (e) and S 5.1.4 (e) state that during the forward and rearward performance tests respectively that "seat components shall not separate at any attachment point."

It has been brought to my attention that this phrase is subject to extreme interpretation which we don't believe National Highway Traffic Safety Administration intended. For example, if 1 out of 100 spotwelds attaching a seatback panel to the frame failed, creating a local separation, would this be considered a non compliance per S 5.1.3 (e) or S 5.1.4 (e)?

We have not used this interpretation. The reasoning for this is that the seat component (back panel) has not separated from the frame.

This is only one example. The same problem occurs in attaching the seat riser to the main frame etc., etc.

Without a clear cut definition of "separate" it is impossible to deal with this phrase. For example, would a torn bracket at a bolt attachment point be a separation? If so, how long must the tear be?

Therefore, we believe the only workable interpretation of S 5.1.3 (e) and S 5.1.4 (e) is to define "separate" as complete separation of one seat component from another; i.e. separation of the seat foot from the riser from the main frame etc.

We solicit your concurrence with this interpretation.

2. The second item deals with S 5.1.4 Seat performance rearward and S 6.5 loading bar.

S 6.5 requires the loading bar to be 4" narrower than the seat width to insure that panel type members are secured in a manner adequate to transmit loads to main seat frame members. We agree with this philosophy.

However, in our testing and development program we have noted an intermitent problem which is directly related to the "narrow" load bar but does not affect seat performance in any way.

The problem is that occasionally the "narrow" load bar will bury itself in the upholstery, padding, and sheet metal and hang up. When this occurs, the load bar begins pulling the seat back in tension creating high apparent loads rather than sliding along the upholstery and only sensing seat back bending loads. Because these tension loads build rapidly, (and exceed 2200 pounds) this phenomenon could be misinterpreted as a seat back which is too rigid.

This phenomenon is intermitent and not always repeatable. It occurs on different seat designs and appears to be related to parameters difficult to define such as padding thickness, the hardness of the loading bar spherical ends, and the coefficient of friction of the upholstery.

One possible solution, if this should occur during compliance testing, is to use the test results from the "narrow" bar test to prove the integrity of the panel to frame attachment and use a wider bar to get true results of seat back performance.

The purpose of this discussion is to go on record as acknowledging this phenomenon and seek confirmation from National Highway Traffic Safety Administration that this would not be judged a non compliance if encountered during compliance testing.

We look forward to your early response on these issues.

W. G. Milby Manager, Engineering Services

ID: nht78-1.4

DATE: 12/06/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Saab-Scania of America, Inc.

TITLE: FMVSS INTERPRETATION

TEXT:

NOA-30

Mr. Ralph T. Millet Director, Governmental Relations Saab-Scania of America, Inc. Saab Drive, P. O. Box 697 Orange, Connecticut 06477

Dear Mr. Millet:

This is in response to your letter of 25 October 1978 concerning the requirements of S3.3 of Standard No. 201 as it applies to the instrument panel compartment door in the Saab 900. Your specific concern is the portion of S3.3 that provides, "Additionally, any interior compartment door located in an instrument panel or seat back shall remain closed when the instrument panel or seat back is tested in accordance with S3.1 and S3.2."

According to your letter, the hinges on the Saab 900 instru- ment panel compartment door are designed to deform to keep the compartment door closed if deformation resulting from the head impact requirements of S3.1 is great enough to open the compartment latch.

If the instrument panel compartment door remains closed during the head impact tests of S3.1, the vehicle complies with that aspect of the requirements of S3.3 of Standard No. 201. The standard does not specify that the latch mechanism remain closed, only that the door "shall remain closed."

This interpretation should not be construed as an approval of Saab's instrument panel compartment door hinge system. Federal motor vehicle safety standards are written primarily in terms of performance requirements which must be met in specified tests, and a manufacturer is free to use any design it wishes to meet those performance requirements. Thus, this agency does not grant approval of specific systems or components in the vehicle. The manufacturer must exercise due care to assure that its vehicles comply with all applicable safety standards.

Please let me know if you have any further questions.

Sincerely,

Joseph J. Levin, Jr. Chief Counsel

Chief Counsel October 25, 1978

Chief Counsel National Highway Traffic Safety Administration U.S. Department of Transportation Washington, D. C. 20590

Subject: Interpretation of Paragraph S3.3 of FMVSS 201

Dear Sir:

Paragraph S3.3 of Federl Motor Vehicle Safety Standard #201 states:

"Interior compartment doors. Each interior compartment door assembly located in an instrument panel, console assembly, seat back, or side panel adjacent to a designated seating position shall remain closed when tested in accordance with either S3.3.1(a) and S3.3.1(b) or S3.3.1(a) and S3.3.1(c). Additionaly, any interior compartment door located in an instrument panel or seat back shall remain closed when the instrument panel or seat back is tested in accordance with S3.1 and S3.2. All interior compartment door assemblies with a locking device must be tested with the locking device in an unlocked position.

When the Saab 900 instrument panel and compartment door is so tested, the compartment door remains in a closed position.

However, in certain head form impact directions, it may occur that the latch disengages and no longer keeps the door closed.

The only acceptable solution we could find to this problem was to design the hinges of the compartment door so that if the deformation after impact is large enough to open the latch, the hinges will deform in such a way that the door thereby remains closed.

We would appreciate your opinion as to whether or not the door remaining closed by the designed locking action of the hinges is considered to be in compliance with Paragraph S3.3 of the Standard.

Very truly yours,

SAAB-SCANIA OF AMERICA, INC.

Ralph T. Millet Director, Governmental Relations

RTM:s

ID: nht78-1.40

DATE: 09/05/78

FROM: AUTHOR UNAVAILABLE; J. J. Levin, Jr.; NHTSA

TO: Thomas Built Buses, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your July 19, 1978, letter asking whether the State of California is preempted from requiring that all seats in school buses be forward facing.

Section 103(d) of the National Traffic and Motor Vehicle Safety Act of 1966 (the Act) (15 U.S.C. 1381 et seq.) specifies that no State shall have in effect a safety standard concerning an aspect of performance regulated by a Federal safety standard, unless the State standard is identical. The Act provides a limited exception to the above where a State or local municipality has a requirement which applies only to vehicles purchased for their own use and which imposes a higher standard of performance.

Standard No. 222, School Bus Passenger Seating and Crash Protection, specifies that seats shall be forward facing except seats designed to transport the handicapped. Seats for the handicapped may be side facing to permit ease of access. The California standard requiring forward facing seats regulates the same aspect of performance, seat orientation, as the Federal standard. Since the California standard is not identical to the Federal standard and, in fact, conflicts with the Federal standard, it is the opinion of the National Highway Traffic Safety Administration that it is preempted.

SINCERELY,

Thomas BUILT BUSES, INC.

July 19, 1978

Office of the Chief Counsel U. S. Dept. of Transportation

Attn: Roger Tilton

Subject: Seats - Side Facing - Handicapped Vehicles

In the Federal Register, Vol. 41, No. 134 - Monday, July 12, 1976, the Federal Motor Vehicle Safety Standards 571.222-S4 was admended to permit side-facing seats in handicapped vehicles.

It has come to our attention that the State of California has a regulation that permits only forward-facing seats.

The question is does the Federal definition that permits the side-facing seats preempt the California regulation?

Thanking you in advance, we remain

James Tydings, Specifications Engineer

ID: nht78-1.41

DATE: 02/21/78

FROM: AUTHOR UNAVAILABLE; Roger Tilton; NHTSA

TO: Docket

TITLE: FMVSS INTERPRETATION

TEXT: SUBJECT: EX PARTE CONTACT

On February 21, 1978, by phone at I met with/(spoke with) Mr. Dick Presno of Sheller Globe Corporation. Discussion: He asked whether a 34 inch seat cushion with a 39 inch seat back would be permitted to have a 30 inch restraining barrier. I told him that, in line with earlier interpretations, a 34 inch seat cushion would require a 34 inch restraining barrier.