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Interpretation ID: 08-00244--139 generic name cord material--3 Jun 08 rsy

Mr. Michael H. Bai

Littleton Joyce Ughetta Park & Kelly LLP

39 Broadway

34th Floor

New York, NY 10006

Dear Mr. Bai:

This responds to your letter requesting an interpretation of one of the labeling requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 139, New pneumatic radial tires for light vehicles. You ask whether, if your client Kumho Tires incorporates lyocell fibers in the cord materials for the tires plies, it would be permissible under S5.5(e) of FMVSS No. 139 to label the tire sidewall with either lyocell or rayon.

Our answer is a qualified yes. We have made a few assumptions in answering your letter. First, we assume that the cord material in question is in fact lyocell and that you simply ask if reference to lyocell or rayon may be used to describe the material. Second, you state that under Federal Trade Commission (FTC) regulations, lyocell and rayon are generic names for lyocell; for the purposes of this letter, we assume your understanding is correct. However, for a complete answer to your question, you should contact the FTC to obtain its concurrence that you have correctly understood the FTC regulation.

By way of background, the National Highway Traffic Safety Administration (NHTSA) is authorized to issue FMVSSs that set performance requirements for new motor vehicles and items of motor vehicle equipment (see 49 U.S.C. Chapter 301). NHTSA does not provide approvals of motor vehicles or motor vehicle equipment.  Instead, manufacturers are required to self-certify that their products conform to all applicable safety standards that are in effect on the date of manufacture. NHTSA selects a sampling of new vehicles and equipment each year to determine their compliance with applicable FMVSSs.  If our testing or examination reveals an apparent noncompliance, we may require the manufacturer to remedy the noncompliance, and may initiate an enforcement proceeding if necessary to ensure that the manufacturer takes appropriate action.


Paragraph S5.5 of FMVSS No. 139 specifies tire markings for new pneumatic radial tires for use on motor vehicles (other than motorcycles and low speed vehicles) that have a gross vehicle weight rating (GVWR) of 10,000 pounds or less. Among the information required by S5.5 to be marked on the tire sidewall, S5.5(e) requires The generic name of each cord material used in the plies (both sidewall and tread area) of the tire. NHTSA requires this information to help tire purchasers select the characteristics they want in a given tire, because the many different cord materials that exist and their many different characteristics enable a tire to be specially geared to its anticipated use.

Your letter states that FTC regulations (16 CFR 303.7(d)) permit the use of the generic name lyocell or rayon where the fabric used is lyocell. NHTSA has previously favorably cited FTC-established generic names for cord materials. In a January 20, 1976 letter of interpretation, NHTSA advised that if Kevlar was used as a cord material in a tire, it must be identified by its generic name, which, NHTSA stated, the FTC established as Aramid pursuant to the Textile Fiber Product Identification Act.

Assuming you are correct that the FTC has established that lyocell fibers may be identified by either the generic name lyocell or the generic name rayon, and because we have previously accepted FTC-established generic names for tire cord material labeling required by the FMVSSs, in our opinion using either lyocell or rayon as the generic name for lyocell tire cords would be acceptable under FMVSS No. 139. However, our answer is conditional on FTC concurrence that the generic names lyocell and rayon are properly applicable to your clients tire cord material. We suggest that you follow up with the FTC on this matter.

I hope this information is helpful. If you have any further questions, please do not hesitate to contact Rebecca Schade of my staff at (202) 366-2992.

Sincerely yours,

Anthony M. Cooke

Chief Counsel

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d.8/25/08