Interpretation ID: nht76-4.36

DATE: 03/19/76

FROM: AUTHOR UNAVAILABLE; R. L. Carter; NHTSA

TO: Almac Plastic Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of February 26, 1976, to Mr. Guy Hunter of my staff, concerning the use of Lucite AR (plastic) glazing materials in rear windows of buses.

Your state that a rubber harness has been designed to allow the plastic glazing to be inserted into the rear window openings of the bus. You further state that once inserted into the rubber harness, the glazing can be easily pushed out and therefore would fall within the definition of readily removable windows. Thus, plastic glazing could be used in such windows.

It is not clear whether the rear bus window you described in your letter would be classified as a readily removable window as defined in Federal Motor Vehicle Safety Standard (FMVSS) No. 205, Glazing Materials. However, if the glazing can be pushed out as easily as you say, it is clear that it would not meet the window retention requirements specified in FMVSS No. 217, Bus Window Retention and Release.

Standard No. 205 specifies requirements for glazing and the vehicle locations in which various types of glazing may be used. The standard prohibits the use of plastic glazing in rear windows of buses unless they are readily removable as defined in the standard. However, in response to a petition submitted by General Motors Corporation, we are currently preparing a Notice of Proposed Rule Making (NPRM) that would amend the standard to permit the use of plastic glazing in all bus windows except windshields and windows to the immediate left and right of the driver. We anticipate that this NPRM will be published in the Federal Register in the near future.

A copy of Standard No. 205 and Standard No. 217 were previously mailed to you. If you have any questions, please do not hesitate to contact me.

Sincerely,

ATTACH.

February 26, 1976

Guy Hunter -- NHTSA

Dear Mr. Hunter:

This is to thank you for the courtesy shown to the writer on the phone. The subject of discussion that we had, was concerning the usage of Lucite AR material on the rear windows of buses.

As discussed, the original window on the rear of most buses is quite expensive and due to vandalism, the windows are cracked by rocks and bottles are extremely dangerous to passengers due to the splintering.

I am enclosing herewith a schematic brochure that we have created which will more clearly indicate this subject.

To accommodate the AA, AC, AD, AB and AE windows a rubber harness has been designed that allows these windows to be inserted. These windows, once inserted into a rubber harness can be easily pushed out with pressure and therefore, can fall into the classification of readily removable windows.

This is the major point that I tried to make over the phone. I feel that rear windows can comply with your regulation of usage of Lucite AR windows and are identical to the regulations that permit the usage of Lucite AR on your side windows.

If any of this information need further clarification, feel free to call upon Mr. Russell H. Berry of DuPont, the manufacturers of Lucite AR, whose telephone number is 302-774-4639. Or feel free to call the writer Mr. Jack Manne, Engineering Department of Almac Plastics at 212-937-1300.

Mr. Berry is extremely knowledgable on this total subject and I am sure that you would find him extremely helpful in any interpretation that is required.

Either he or I would be pleased to visit with you in Washington, DC if a meeting would assist your decision in this subject.

Thanking you kindly for any attention you give this matter, we beg to remain

Very truly yours,

Jack Manne -- Engineering Department, ALMAC PLASTICS INC.

Enc.

CC: R. H. Berry -- DuPont

(Brochure Omitted)