Interpretation ID: nht75-4.22

DATE: 04/03/75

FROM: AUTHOR UNAVAILABLE; J. C. Schultz; NHTSA

TO: Ventline, Inc.

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of February 27, 1975, regarding the use of rubber-modified polypropylene plastic in a roof ventilator which you manufacture. You enclose a sample of the material.

A plastic material used in the roof ventilator of a motor home must meet the requirements of Motor Vehicle Safety Standard No. 205 (49 CFR @ 571.205). Our conclusion is based on the fact that ANS Standard Z26.1-1966, which is incorporated into the Federal standard, includes ventilators and openings in the roof of motor vehicles as locations in which glazing materials meeting the requirements of the standard are directed to be used. Any of the materials specified in ANS Z26, and the plastic materials added to the standard (items 12 and 13) on November 11, 1972, may be used in a roof ventilator of a motor home. We would consider such a ventilator to be a "window" of the motor home.

The NHTSA has in the past amended Standard No. 205 to permit the use of new materials in vehicle locations following a manufacturer's petition for such an amendment. It appears from your letter that the use of polypropylene in roof ventilators would not create a safety hazard. However, in order for us to consider a change in the standard it will be necessary for you to provide us with information on the performance of this material. One way that manufacturers have provided us this information in the past is to have the material tested to the least restrictive requirements of the standard for any material which the standard permits to be used in the location desired.

I have enclosed a copy of NHTSA procedural rules (49 CFR Part 523) containing information on submitting a petition for rulemaking. Such a petition should contain the information I have referred to regarding the performance of polypropylene.

In your letter you ask for a code number should we determine that the material must conform to Standard No. 205. A code number, however, is issued only to a prime glazing material manufacturer, who is one who either fabricates, laminates, or tempers the glazing material. The request for such a code number must be made directly by the prime glazing material manufacturer.

Sincerely,

ATTACH.

February 27, 1975

Chief Counsel -- National Highway Traffic Safety Administration

Ref: F.M.V.S.S. 205

Gentlemen:

Ventline, Inc. is a manufacturer of roof ventilators for motor homes and campers. We are trying to determine if F.M.V.S.S. #205 applies to our product. (literature enclosed.)

The purpose of this standard mentions, (1) injuries from impact with glazing surfaces, (2) ensurance of driver visibility in motor vehicle windows, (3) minimize possibility of occupants being thrown through windows in collisions.

(1 & 3) As far as injuries from impact go, the possibility of contact with the dome in a collision is very remote since the opening in the unit is only 12 inches square and that area is blocked by a heavy gage steel bar across the opening which makes it most difficult to come into direct contact with the plastic dome.

(2) The concern of transparency and driver visibility is completely unrelated to the intent of the vent. It is installed in the roof of the vehicle, not one of the adjacent sides to areas occupied by persons, and is used primarily for ventilation. It also allows a limited amount of light through the "TRANSLUCENT" not transparent dome. It's intent was not to provide visibility through the roof.

The material used in this dome is a rubber modified polypropylene plastic which has superior impact resistance. As you can see by the small sample I have enclosed, it also has a good degree of flexibility to resist breakage.

To the best of our knowledge, there isn't any glazing being done with polypropylene because of the difficulty of obtaining good transparency, so it doesn't seem to us that our dome should be considered glazing material and shouldn't have to comply with F.M.V.S.S. #205.

If in your opinion, after considering these points, you feel that we must comply with #205, please consider this our application for a manufacturers code mark.

We are eagerly awaiting your decision on this matter.

Sincerely,

VENTLINE, INC. -- Dave Bickel, Product Engineering

enclosure

cc: Harry Hunt; Ernie Baker