Interpretation ID: nht79-1.38

DATE: 01/24/79

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

TO: Mercedes-Benz of North America, Inc.

TITLE: FMVSS INTERPRETATION

TEXT:

JAN 24 1979 NOA-30

Mr. Heinz W. Gerth Mercedes-Benz of North America, Inc. One Mercedes Drive P. O. Box 350 Montvale, New Jersey 07645

Dear Mr. Gerth:

This responds to your letter of December 19, 1978, asking whether a manually adjustable seat belt anchorage for the upper torso portion of a 3-point safety belt is permissible under Safety Standard No. 210, Seat Belt Assembly Anchorages. You state that this new anchorage is adjustable over a certain range and is intended to increase wearing comfort by providing a better "fit" for all occupants.

We have reviewed the drawings and specifications enclosed with your letter and determined that the proposed adjustable anchorage design would not be precluded by Safety Standard No. 210 if the design meets the following two conditions: (1) the anchorage complies with the zone location requirements of the standard in any of the positions to which can be adjusted, and (2) the anchorage complies with the strength requirements of the standard at all times, even when the adjusting mechanism (bolt) is in its loosened status. There is nothing in the standard that prevents the use of adjustable anchorages, per se.

From discussions with your engineers, we found that the proposed design would require the use of a tool to tighten the adjusting bolt. We are concerned that this feature could reduce potential increases in belt use. For example, if driver A adjusts the belt anchorage to its lowest position, will driver B readjust the belt when he enters the car if the two drivers are of different sizes and the lowest position is uncomfortable for driver B? If the readjustment requires the use of a wrench to loosen and retighten the anchorage bolt, will driver B simply choose not to wear the belt? We believe that a manually adjusting anchorage that does not require the use of tools would be a preferable design in terms of potential seat belt use.

The agency is of course very interested in any seat belt design that will increase comfort and convenience and, thereby, seat belt use. Therefore, we encourage innovative designs. Please keep us informed about the progress of your work on your new anchorage system.

The National Highway Traffic Safety Administration hereby grants your request for confidential treatment of the drawings included in your letter (enclosures 1, 2 and 4). We have preliminarily determined that the drawings and specifications contain privileged commercial information that is exempt from disclosure under 5 U.S.C. 552(b)(4).

Sincerely,

Joseph J. Levin, Jr. Chief Counsel

December 19, 1978

Docket Section Room 5108 National Highway Traffic Safety Administration 400 Seventh Street S.W. Washington, D.C. 20590

Re: Standard 210; Seat Belt Anchorages - Request for Interpretation

Gentlemen:

Statistics released by the NHTSA on December 15, 1978, again reflect the very low seat belt usage rate in the United States inspite of their known effectiveness. Earlier surveys have shown that approximately 50% of persons refusing to wear seat belts do so because they perceive them to be uncomfortable and inconvenient to manipulate and wear.

In an effort to overcame this wide spread public perception, our parent company, Daimler-Benz A.G., has devised 2 manually adjustable anchorage for the shoulder portion of the 3-point safety belt. The anchorage is adjustable over a range of 90mm and is designed to increase wearing comfort by providing a better "fit" for all occupants ranging from the 5 percentile female to 95 percentile male.

Daimler-Benz has tested this device and has concluded that it conforms to the strength requirements of standard 210. However, it is not entirely clear if such a device per se is permissable under the Standard.

We are including with this communication a written description of the device, and several drawings and photographs. We request your review of the material and advice if the manually adjustable seat belt anchorage is, in fact, permissable under Standard 210. If additional information is requested, please do not hesitate to contact this office.

In closing we would like to draw your attention to enclosures 1, 2 and 4 which we consider to contain proprietary information which would be damaging to our competitive interests if released to the public. We request that these enclosures be withheld from the public docket in accordance with 5 U.S.C. Section 552 (b)(4).

Yours truly,

Enclosures

"Proprietary"

We request that the information designated 'proprietary' in the enclosure be treated by the agency as confidential and be exempted from disclosure under 5 U.S.C. Section 552(b) (4) because such information is a trade secret and contains privileged commercial information. Knowledge of this information to competitors could result in significant competitive damage to Mercedes-Benz of North America, Inc.

Enclosure 3

Description

The upper safety belt anchorage consists of an "M" shaped base plate (1) which is attached with screws at points (6) and (7), and tabs at point (5) to the "B" pillar, and which holds the adjustable retaining plate (2) in place on which the mounting nut (4) for the belt sash is spot welded, and which also holds the spring-loaded belt arresting device (3).

The base plate (1) has, depending on the adjustment travel of the seat belt sash (8), an elongated hole (1a) in the middle to permit a screw (9) to pass through and fasten the belt sash to the retaining plate (2).

Within the elongated hole (1a) three indexes (10),(11), & (12) are arranged in pairs to receive the spring-loaded belt arresting device (3) and hold the retaining plate (2) in place. Because of the way the retaining plate (2), and the arresting device (3) are configured, it is assured that when loaded the arresting device (3) will lock into place as there is no arm between the projection (13), and the indexes (10),(11), & (12) which could cause a moment to be exerted on the arresting device (3). An additional pre-condition for the uninterrupted functioning of the arresting device (3) is that the restraining plate (2) to which the arresting device (3) is attached, does not lift off the base plate when loaded. This is achieved with the threaded (9) connection to the retaining plate (2), and by means of two tabs (2a) which, when loaded, rest against the B-pillar. This assures that the arresting mechanism (3) is loaded only by shear forces.

PS:Wkr 11/9/78