The Transportation Recall Enhancement, Accountability and Documentation (TREAD) Act was passed by Congress in 2000 in response to a major recall of defective tires that created unsafe driving conditions and multiple driver fatalities (one hundred deaths due to rollovers were attributed to tire tread separation). The TREAD Act has since been incorporated into the existing National Traffic and Motor Vehicle Safety Act of 1966.
Among other mandates, the TREAD Act requires the system warning the driver about underinflated tires to be included in vehicles sold in the U.S. as of September 1, 2007. The warning system, or tire pressure monitoring system (TPMS), has to be placed in 100% of all passenger cars and light trucks (under 10,000 lbs. Gross Vehicle Weight). Automakers and their suppliers must also notify the National Highway Traffic Safety Administration (NHTSA) of all accidents involving alleged defects.
The TREAD Act (via Federal Motor Vehicle Safety Standard 138) requires original car manufacturers to equip all new vehicles with:
- Monitoring of tire pressure in all four tires (but not the spare tire)
- A TPMS system that operates when the vehicle ignition is on and warns the driver when tires are underinflated by 25% or more
- A TPMS system that alerts the driver when there is a system malfunction
- A TPMS warning light that stays on until the tire is inflated to the proper pressure or the system malfunction is corrected
- A "bulb check" of the warning light on the instrument panel that occurs whenever the ignition is turned on
- Vehicle owner's manuals that contain warnings about potentially incompatible replacement tires for the vehicle
TPMS Effectiveness – Significant Results
TPMS Effectiveness in Proper Tire Pressure Maintenance – in this November 2012 study, NHTSA completed an extensive survey of vehicles to measure the effectiveness of TPMS in protecting drivers from underinflation situations. The data showed that the presence of TPMS was estimated to result in a 55.6% reduction in the likelihood the vehicle would have one or more severely underinflated tires.
Tire Pressure Maintenance – A Statistical Investigation – in 2009, NHTSA conducted several surveys and studies to estimate and compare the benefits of Direct and Indirect TPMS. The results are presented in this report.
Tire Pressure Monitoring System FMVSS No. 138 – the final regulatory impact analysis of the TREAD Act, from the National Highway Traffic Safety Administration. Published in 2005.