Interpretation ID: nht81-2.7

DATE: 03/20/81

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: W. Roger Fry, Esq.

TITLE: FMVSS INTERPRETATION

TEXT:

NOA-30

W. Roger Fry, Esq. Rendigs, Fry, Kiely & Dennis 900 Central Trust Bank Tower Fourth & Vine Streets Cincinnati, Ohio 45202

Dear Mr. Fry:

This responds to your January 23, 1981, letter concerning tires used with multipiece rims. Specifically, you asked if this Department has considered whether tires should have a warning concerning use with mismatched multipiece rim assemblies.

We have not considered this question, nor have our studies of multipiece rim explosions considered the tires involved. The agency has determined through its investigations that mismatched multipiece rim assemblies are dangerous. These mismatched assemblies are highly prone to explosive separation, regardless of the nature of the tire mounted on them. Accordingly, our efforts have been directed toward labeling requirements for rim components (see the enclosed copy of Federal Motor Vehicle Safety Standard No. 120) in an effort to reduce the incidence of mismatched multipiece rim assemblies. There are no labeling requirements for tires which specifically warn against use with mismatched multi-piece rim assemblies.

Per your request, I have enclosed a copy of Federal Motor Vehicle Safety Standard No. 119, New Pneumatic Tires for Vehicles Other Than Passenger Cars (99 CFR S 571.119). Section S6.5 of this standard specifies the marking requirements for these tires. This standard took effect on March 1, 1975, and the enclosed copy represents the requirements which were applicable from that date to December 31, 1975.

This regulation does somewhat restrict the markings a manufacturer may put on the sidewall of its tires. For instance, the manufacturer cannot list more than one size designation (S6.5(c)) or more than one maximum load rating for single and dual loads (S6.5(d)). However, a manufacturer is free to include safety information in addition to that specified in section S6.5. Thus, a manufacturer might choose to print on the sidewall of its tires that the tires should only be used with a specified rim size or type. Such an additional warning need not be approved by this agency. In fact, this agency does not offer advance approval that a tire's markings comply with the requirements of Standard 119. It is the manufacturer's responsibility to determine that its tires are in compliance with applicable safety standards and to certify that compliance.

If you have any further questions or need further information on this matter, please feel free to contact Mr. Stephen Kratzke of my staff at (202) 426-2992.

Sincerely,

Frank Berndt Chief Counsel

Enclosures

January 23, 1981

United States Dept. of Transporation National Highway Safety Administration Washington, D.C. 20591

Gentlemen:

I am involved in a matter in which I represent the manufacturer of a truck tire which was on a vehicle when a multi-piece rim suddenly came off and critically injured someone in the immediate vicinity of the tire and rim. The rim had been assembled, in some manner with incompatible parts from different manufacturers, which parts combined both two-piece and three-piece rim assembly parts.

My question of you surrounds the tire itself. Has the Department addressed the question of whether or not the tires shou1d have any kind of warning regarding use with either mismatched multi-piece rim assemblies, or multi-piece rim assemblies generally?

I would be very interested in seeing your regulations and requirements governing data which is to be legible on the tire itself, auch as tire size, maximum air pressure and identifying marks. Could you send me your regulations which we in force in 1975?

Do your regulations restrict the printing on tires to the specific items covered in your regulations, or is a tire manufacturer free to add and delete other messages?

Must "other messages" be approved by you?

Have your studies of injuries with multi-piece rim assemblies included consideration of the tires themselves? If so, to what extent?

Thank you very much for any help you are ab1e to give me on this.

Very truly yours,

RENDIGS, FRY, KIELY & DENNIS

W. Roger Fry

WRF:rst