Driven by product liability concerns as well as consumer safety, the Rubber Manufacturers Association July 19 asked a federal agency to adopt a new requirement that motor vehicle tires have a reserve inflation pressure.
The group's petition for a new, separate rule follows its unsuccessful lobbying to get a reserve worked into the tire pressure monitoring regulation the National Highway Traffic Safety Administration released June 5.
``Our view is that NHTSA did not get the tire pressure monitoring system rule right,'' an RMA spokesman said. ``Rather than promote safety, it will, in many cases, fail to warn motorists when their tires have reached a dangerous pressure,'' giving them a false sense of security.
Tire makers contend because recommended inflation pressures aren't set high enough in the first place, damage to the interior of the tire already is occurring after deflation of 25 to 30 percent, as allowed under the tire pressure monitoring rule.
In the case of future tire failures on vehicles equipped with a pressure monitor, as the NHTSA rule stands now, people could reasonably conclude that pressure could not have been the cause because their monitors did not alarm them, the RMA spokesman said.
Lawyers' natural conclusions from there could have them arguing that the tires had manufacturing flaws, he said.
In its petition, the RMA is proposing that auto makers be required to recommend an inflation pressure sufficient to carry the vehicle load even at pressure losses as great as 30 percent.
The safety administration has 120 days to respond to the filing.
``We think the agency should not be diverted or distracted from completing its rulemaking to upgrade the tire performance standards which is the core of the Transportation, Recall, Enhancement, Accountability and Documentation (TREAD) Act,'' said Rob Strassburger, vice president of vehicle safety and harmonization for the Alliance of Automobile Manufacturers.
Meanwhile, the two top congressmen in the House Energy and Commerce Committee are backing the RMA's demand for a federal rule establishing a reserve inflation pressure for tires. Committee chairman Billy Tauzin, R-La., and ranking minority member Edward Markey, D-Mass., who presided over both the hearings leading up to the TREAD Act and oversight hearings after its passage, endorsed the RMA petition as a necessary safety precaution.
``As NHTSA's own data shows, the underinflation of tires is not an isolated issue,'' they wrote in their joint letter. The agency's own figures show that 27 percent of passenger cars and 32 percent of light trucks have at least one severely underinflated tire, and consumer surveys show that 90 percent of motorists don't know how to maintain tire inflation properly, the congressmen said.
The safety agency considered the idea of a tire pressure reserve nearly a quarter of a century ago in the wake of the Firestone 500 recall, Mr. Strassburger said, and found that there would be no ``real-world'' safety benefits from such reserves.
Just the same, car makers already have built-in pressure reserves, he said. ``With the vehicles that are of the most concern right now-the SUVs-there's a minimum (reserve) of 10 percent.''
With its petition to NHTSA, the RMA included a set of data from a sample of 100 vehicles. If that group of vehicles was equipped with a tire pressure monitoring system, by the time the device alerted drivers to a pressure loss of 25 to 30 percent, the integrity of the tires on 73 of the vehicles would be damaged, according to the RMA.
For those 100 vehicles, if the recommended inflation pressure was raised by 5 psi, 67 of the vehicles would give a timely alarm, the RMA spokesman said.
Washington reporter Miles Moore contributed to this report.