^®: CRE Regulatory Action of the Week

Proposed NHTSA Tire Safety Tests Produce Random Results
The tire safety tests and other information in NHTSA’s FMVSS No 139 rulemaking do not comply with the standards set by the Department of Transportation’s Data Quality guidelines. Of particular concern, two key tests, the endurance test and the high speed test, are unreliable and produce essentially random results. NHTSA documents in the docket state that "4 of 8 tire brand/model failures were consistent with this [NHTSA’s] theory [of how tires should perform in the endurance test.]" The NHTSA test documents for the high speed test demonstrate that only 3 of 8 tire brand/model failures were consistent with the agency’s theory of how tires should perform in the test. NHTSA’s theory was that the same brand/model of tire would accumulate more failures when subjected to tests the agency believed to be of increasing stringency. If the tires performed according to theory, it would demonstrate that the proposed tests could distinguish between stronger, i.e. potentially safer tires, and tires which were not as strong. Since the relationship between tire failure and the agency’s perception of test stringency was essentially random for both the endurance and high speed tests, the tests do not provide useful information regarding tire safety and, thus, lack utility as defined by the OMB and DOT Data Quality guidelines. CRE’s analysis of the rulemaking’s compliance with the Department’s Data Quality guidelines clearly indicate that substantial work will be needed for a final rule to meet the Department’s stringent pre-dissemination review requirements.