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Interpretation ID: aiam3537

Mr. John B. White, Engineering Manager, Technical Information Dept., Michelin Tire Corporation, One Marcus Avenue, Lake Success, NY 11042; Mr. John B. White
Engineering Manager
Technical Information Dept.
Michelin Tire Corporation
One Marcus Avenue
Lake Success
NY 11042;

Dear Mr. White: This responds to your recent letter requesting an interpretatio concerning the requirements of 49 CFR Part 574, *Tire Identification and Recordkeeping*. Specifically, you asked whether Michelin could use two different size codes in the tire identification number to identify tires of the same size. You asserted that this assignment of differing size codes would not impair Michelin's ability to conduct a recall of tires of that size, should such a recall be necessary. As long as Michelin maintains accurate records of the size codes assigned to the various tire sizes, it would be permissible to assign more than one size code to each tire size.; At the outset, it is important to note that the size code in the tir identification number is not the means used by the consumer to determine the size of the tires on his or her car. Section S4.3(a) of Standard No. 109 and section S6.5(c) of Standard No. 119 specify that the tire size designation must be labeled on both sidewalls. The size designation is the exact size and is not the same as the size code. To satisfy this requirement, Michelin should label all tires of the same size with just one size designation.; For purposes of record keeping, paragraph S574.5 requires that eac tire be labeled with a tire identification number, and that this identification number contain four groupings of information. The first grouping is a symbol identifying the manufacturer (the symbol is assigned by this agency), the second grouping is a symbol identifying the tire size, the third grouping is an optional symbol containing further information on the specific characteristics of the tire, and the fourth grouping is a symbol identifying the week the tire was manufactured.; There is no requirement in Part 574 which prohibits more than one tir size code from being assigned to each tire size. Additionally, the purpose of tire identification number requirements in Part 574 is to facilitate effective recalls of the tires from the public if those tires are found not to comply with an applicable safety standard or if the tires contain a safety-related defect. For tire manufacturers such as Michelin, this purpose is served by the requirement that the manufacturer keep records of the names and addresses of the initial purchaser of each of its tires for at least three years, as specified in paragraph S574.7. As you noted in your letter, this purpose would not be defeated if a manufacturer assigns more than one size code to a given tire size. Accordingly, a manufacturer may assign more than one size code in the tire identification number for a given tire size, since this is not specifically prohibited by Part 574 and does not conflict with the purpose of that Part.; Sincerely, Frank Berndt, Chief Counsel