News reports the past few years of multi-million tire recalls and the linking of hundreds of deaths and injuries to alleged tire failures might easily create the impression that tires are failing in alarming numbers.
But this is hardly the case as can be seen by weighing such incidents against the estimated 800 million tires on U.S. roadways.
The chance of any one of these 800 million tires being a factor in an accident that results in injuries or fatalities is one in 76,923, or 0.0013 percent, according to the Rubber Manufacturers Association, citing National Highway Traffic Safety Administration data.
Expressed another way, only one in 900 traffic accidents in any given year-or 0.1 percent-involves an alleged tire failure, according to an analysis of NHTSA crash data. And in this case, tire failures were for all kinds of reasons-punctures, road hazard damage, crash damage, run underinflated and/or overloaded and manufacturing defects. Neither the agency nor the RMA is able to provide a breakdown of failure causes.
Measured over time, NHTSA has recorded 503 tire recalls since 1969, involving 45.6 million tires. Compared with the number of tires sold in the U.S. during that same time period-an estimated 7.5 billion-yields a recall concentration of only 0.6 percent, or one tire recalled for every 167 sold.
Discounting the Firestone recalls of 1978 and 2000/2001, the number of tires recalled drops to 13.5 million over 34 years and the recall percentage to 0.2 percent, or one for every 555 sold.
Of course, tires recalled does not equal tires failed. In any given recall, the actual number of recalled tires that might have failed is only a fraction of the total, thereby reducing the failure potential of a single tire, according to an analysis of selected recalls.
Looking at the Firestone Wilderness/ATX recall-the most carefully scrutinized tire action in history-NHTSA has approximately 5,200 accident reports in its database that it says involved a Wilderness or ATX tire.
Consider that the recalls in 2000 and 2001 encompassed 17.2 million tires (of which about 10 million already were out of service by the time the recalls were announced in August 2000 and October 2001, respectively), and the accident/tire ratio works out to 0.03 percent, or one accident for every 3,308 tires sold.
The number of accidents where injuries or deaths occurred divided by the number of recalled tires yields a ratio of 0.005 percent, or a one in 20,877 chance.
By comparison, the odds of dying in a transportation accident in 2000 were 1 in 5,889, while the odds of dying as an occupant of a car or pickup truck/van were about one in 18,000, according to the National Safety Council.
The odds likely will rise slightly for 2002 as highway fatalities last year were up 14 percent to 42,815, the highest level since 1990, according to U.S. Department of Transportation statistics. Fatalities in rollover crashes accounted for 82 percent of the increase.
The Ford Explorer/Firestone Wilderness tragedy likely was made worse by the low incidence of seat belt use by those injured or killed in rollover accidents. A NHTSA analysis has found that as many as one-half to three-fourths of those injured or killed in rollovers weren't wearing seat belts.