One-third of current passenger and light truck tires on the nation's roadways couldn't pass the National Highway Traffic Safety Administration's proposed high speed and endurance tests, the agency said.
Furthermore, the overall annual costs to tire makers of implementing these test procedures-themselves only part of a larger tire performance standard from the National Highway Traffic Safety Administration-would be $282 million, according to NHTSA.
At this point, however, no one is too worried about these figures, as nearly everyone in the industry is still trying to absorb the 79-page document that appeared on NHTSA's Web site Feb. 28 and in the Federal Register March 5.
``We've barely scratched the surface,'' a spokesman for the Rubber Manufacturers Association (RMA) said. ``It will take us a number of weeks to delve into it.'' The government's cost estimates have to be considered speculative, he said.
``We are also looking to see that tires aren't forced to perform beyond their design capabilities,'' the RMA spokesman said, adding: ``Today's tires are safe.''
Spokespersons for Bridgestone/Firestone, Cooper Tire & Rubber Co. and the Tire Association of North America also said they were too busy studying the proposed standard to make a definitive comment.
``We'll have to go to industry experts to see if this is something we can live with,'' said Becky MacDicken, TANA director of government affairs.
But the RMA has already said the proposal leaves unanswered a major concern it has in general with tire regulations arising from the Transportation Recall Efficiency, Accountability and Documentation (TREAD) Act. That concern is whether there will be a minimum reserve load requirement created to offset a drop in the load range of tires-a condition created by the pending final rule for tire pressure monitoring devices.
Under the proposal, NHTSA would create a new standard-Federal Motor Vehicle Safety Standard No. 139-for performance of new tires on vehicles weighing 10,000 pounds or less. NHTSA suggested alternative compliance dates of Sept. 1, 2004, or Sept. 1, 2005, for the rule.
The current standard for such tires-FMVSS No. 109-was issued in 1968, before the radialization of the tire industry and the adoption of many technologies now well established in tire making.
In January 1999, NHTSA granted the RMA's petition to revise the outdated standard, but still had not acted on the petition in August 2000 when Bridgestone/Firestone announced the recall of 6.5 million tires. The recall-and the incidents of tread separations that spurred it-brought widespread attention in Congress and the press to the long-overdue revision of the tire rule. The mandate for a new standard was a cornerstone of the TREAD Act.
The NHTSA document sets forth tougher high speed, endurance and bead unseating tests for tires, as well as new tests for road hazard impact, low inflation pressure performance and aging effects.
In the high speed test, for example, tire makers would have to test their tires at speeds of 88, 94 and 100 mph, compared with the current standard's requirements of 75, 80 and 85 mph. The proposed new endurance test increases the required speed 50 percent, from 50 to 75 mph; it also increases duration from 34 to 40 hours and distance from 2,720 to 4,800 kilometers.
The new bead unseating and road hazard impact tests are based on models from Toyota Motor Corp. and the Society of Automotive Engineers, respectively, the agency said. The road hazard impact test replaces the strength test included in FMVSS No. 109, it added.
Low inflation pressure performance and aging effects were included in the testing to answer specific congressional questions about tire performance under those circumstances, NHTSA said in the summary of the proposal.
``In particular, underinflation and heat were factors highlighted as contributing to failure of the Firestone ATX and Wilderness tires in the TREAD hearings and in the agency's Firestone investigation,'' it said.
For low inflation pressure performance, NHTSA proposes two alternative tests, based on agency testing and data analyses, while for aging effects it identifies three alternative tests using peel strength, long-term durability and oven aging.
NHTSA estimates that 32.8 percent of the current new tire population would need improvements to meet the high speed and endurance requirements in the proposed standard.
The tires in question are primarily those with a ``C'' temperature resistance grade under the government's Uniform Tire Quality Grading program.
To bring those tires up to code, the agency said it will cost $282 million a year, based on estimated production of 64 million original equipment and 223 million replacement tires. This works out to $4.09 per vehicle or $7.2 million per life saved, according to NHTSA.
It did not estimate any cost increases associated with the other tests, because it said most current tires would pass them.
Another feature of the proposed rule is that it would require the load of cars and light trucks with three adult passengers to be no more than 85 percent of the load-carrying capacity of the tires at the recommended inflation pressure, compared with the current limit of 88 percent.
``This proposal is designed to ensure that there will be an adequate reserve of load-carrying capacity in the tires,'' the agency said.
Earlier, the RMA protested what it said was an unintended drawback to NHTSA's proposal on tire pressure monitoring devices. That rule, the association said, would lower the load range of tires by 10 percent, and it recommended a minimum reserve load rule to ensure the safe running of the tires.
NHTSA's 85-percent proposal on load-carrying capacity does not answer the RMA's concerns, according to an association spokesman. ``This has nothing to do with load range,'' he said, adding that the RMA will continue to seek a minimum reserve load rule.
May 6 is the deadline for comments on the proposed standard.