NHTSA Study: Underinflated Tires Can Cause Accidents
A new study finds that tires that are underinflated by 25% or more are three times more likely to be involved in an accident related to tire problems. As David Shepardson reports for The Detroit News, the study — of crash data from 2005 through 2007 — indicates that passenger cars accounted for 66% of the tire-related accidents. Only 5% of the crashes in the period the study looked at involved tire problems, Fox News notes.
The study, by the National Highway Traffic Safety Administration (NHTSA), found that poorly maintained or underinflated tires were more likely to have problems in inclement weather. The researchers found that 11.2% of the vehicles studied had problems linked to tires when the weather was bad, as compared with only 3.9% in good weather.
Dan Zielinski, senior vice president for public affairs for the Rubber Manufacturers Association, said the study reiterated the need to properly maintain and inflate tires.
When tires are not properly inflated, they don’t grip the roadway as well. Heat can build up, which can lead to a failure. […]
Prior studies have shown that 28 percent of vehicles on the road have at least one tire underinflated by 25 percent or more.
Congress passed a law in 2000 mandating that all vehicles contain a tire-pressure monitoring system by 2008. The law requires the monitoring systems to alert drivers when any tire is 25% or more below its recommended inflation level and is driven for more than 20 minutes. As Shepardson explains, the system’s radio transmitter alerts the driver by sending a signal to a computer on the car that provides a warning signal on the dashboard.
Fox News writes that a previous NHTSA study found that while only 43% of vehicles on the road had properly inflated tires, that number jumped to 57% among vehicles equipped with the tire-monitoring systems. John Rastetter, head of testing for Tire Rack, told Fox News that underinflated tires do not just affect a car’s handling, but under stress, the stretching rubber of such tires pulls away from their reinforcing materials underneath, resulting in tire failure.
Rastetter said drivers should check and fill their tires the first thing in the morning. “Topping off in the afternoon or evening can lead to a loss of up to 6 psi of pressure overnight from a 35 psi tire,” he said. He also advises drivers not to wait until tires look flat, as Fox News reports:
Most people have a hard time telling the difference between a full tire and one that’s 25 percent low, Rastetter says. By the time tires start to noticeably bulge they’re likely already more than 50 percent low.
Owners should also check their car’s manual for additional information, as pressure recommendations can vary for vehicles being used for towing and under other extreme conditions.
Car owners need to check the pressure in their spare tires, as well, he said, which “can drop from a standard pressure of around 60 psi to below 10 psi over time, possibly making them more dangerous than they are worth.”
The following video shows how to inflate your car’s tires: