NHTSA nears final standard for tyre fuel efficiency testing

ERJ staff report (R&PN)

Washington DC -- tyre industry stakeholders have a lot of work ahead to ensure they get the tyre testing parameters and consumer information plans they want in the tyre fuel efficiency ratings final rule.

The 195-page standard's March 25 issuance on the National Highway Traffic Safety Administration Web site made that plain, and a meeting on the consumer information portion of the rule at NHTSA headquarters the next day made it even plainer.

As recommended in the proposed regulation issued in June 2009, the final rule makes Test 28580, developed by the International Organization for Standardisation, the basis of the standard's rolling resistance test.

“The ISO 28580 test method is unique in that it specifies a procedure to correlate results between different test equipment,” NHTSA said in the final rule. However, the agency put off decisions such as the specification of Lab Alignment Tires for rolling resistance testing and also whether to specify the Rolling Resistance Coefficient or Rolling Resistance Force as the metric for determining fuel efficiency ratings.

The final rule stipulates the safety (traction) and durability (treadwear) ratings for the fuel efficiency standard would be the same as those required under the Uniform Tire Quality Grading System. The traction test, however, may require a one-time modification in the software, NHTSA said.

The agency will retain UTQGS requirements for the time being, the final rule said. However, if the final version of the consumer information portion requires printing the fuel efficiency ratings on the paper or plastic label on a new replacement tyre, NHTSA may consider rescinding the requirement to print UTQGS ratings on the labels and mould them on sidewalls to avoid confusion, it said.

NHTSA also withheld requirements for the consumer information part of the rule, but said it would re-propose those ideas in a supplemental proposed rule to be issued later this year.

The agency also said it would establish a new Web site on tyres, linked directly to www.safercar.gov, which will contain all the information on NHTSA's current tyre Web site as well as links to Web sites that provide information on tyre maintenance.

Disagreements abound

Strong differences of opinion in these areas necessitated further action and comment, Mary Versailles, the NHTSA official who is leading the effort to finalize the tyre fuel efficiency standard, said at the March 26 meeting.

“When the tyre research is done, we want to be confident in making our choices, and know who the critics will be and won't be,” Versailles said.

Completing the process for an absolutely “final” tyre fuel efficiency standard will take some time, according to Versailles. For example, the Office of Management and Budget will need to weigh in on the supplemental proposed rule on consumer information after the public comment period ends.

Nevertheless, she said, tyre makers had better be prepared to expedite testing once the rules are set. “If the lab notice comes out on Aug. 10 and the consumer education notice doesn't come out until Dec. 11, there's probably a good chance we won't give you two years from Dec. 11 to start reporting ratings,” she said.

Both the Tire Industry Association and the Rubber Manufacturers Association-representing the two largest blocs of industry stakeholders in the fuel efficiency rule-said at the meeting that NHTSA's consumer information proposals were seriously flawed.

Both associations, for example, objected to NHTSA's recommendation that the paper or plastic label placed on every new replacement tyre should be the main vehicle for conveying the new standard's fuel efficiency, safety and durability ratings.

“On its face, it makes perfect sense,” said Roy Littlefield, TIA executive vice president. “But in actual practice, it's untenable.”

Not only do tyre buyers rarely get a close look at those labels, Littlefield said, but a tyre retailer would have to pull several different brands of the same size tyre out of his warehouse to give customers a fair comparison.

NHTSA's assumption that most replacement tyre purchases are a reasoned, well-researched choice is also faulty, according to Littlefield. “A majority of tyre sales are spur-of-the-moment and based on immediate need,” he said.

To develop an accurate understanding of how consumers choose tyres, NHTSA needs to have at least 1,000 responses at the point of sale from multiple geographic regions to ensure a diverse socioeconomic and ethnic sample, Littlefield said. He offered TIA's services in gathering that information.

Educating consumers at the point of sale-with brochures, Internet sites and trained sales personnel to explain the ratings system and help with tyre choices-is the best way to make sure the tyre fuel efficiency grading system is a success, Littlefield said.

TIA volunteers

From the beginning of the rulemaking process, TIA has put itself forward as the logical group to administer the consumer information program, because of its wide network of member dealers and demonstrated expertise in personnel training.

The Rubber Manufacturers Association-which championed the original legislation creating a mandate for a tyre fuel efficiency grading and consumer information system-generally agrees with TIA as to what would constitute a useful system.

An effective ratings system must provide information at the point of sale; be both meaningful and easy for consumers to understand; differentiate between rolling resistance, traction and treadwear as important aspects in tyre choice; and be cost-effective for consumers, said Daniel Zielinski, RMA senior vice president for public affairs.

In response to the NHTSA consumer research cited in the proposed rule, the RMA undertook its own comprehensive consumer research to test potential tyre information formats, Zielinski said.

The association presented five information formats to an Internet survey of 1,000 participants, Zielinski said.

Whereas NHTSA found that a plurality of consumers favored the “Thermometer” style of ratings on a 0-100 scale, the RMA found that the greatest number of votes went to a “Star” system of one to five stars for each category. The RMA survey showed 33 percent voting for the Star system versus 29 percent for the Thermometer system, with lesser percentages going for the “5-Box Vertical,” “5-Box Horizontal” and “Thermometer Category” systems.

Support for the Thermometer system fell to 19 percent when consumers were told a 0-100 rating was by its very nature imprecise.

“A 0-100 scale is impractical,” Zielinski said. “tyres with ratings within 10 to 20 points of each other are not likely to have significantly different performance.”

Zielinski also argued for the use of the RRC as the metric to determine rolling resistance ratings, as opposed to the RRF NHTSA favored in its proposal.

“Rolling Resistance Force will minimize differentiation, whereas the Rolling Resistance Coefficient is more suitable to provide a range of choices to consumers,” Zielinski said. Europe and Japan have already specified the RRC for their rolling resistance testing, he said.

Also appearing at the March 26 meeting was Walter H. Waddell of ExxonMobil Chemical. Waddell argued for the use of his company's halobutyl inner liners to achieve the consistent tyre pressures necessary to make tyre fuel efficiency ratings meaningful.

From Rubber & Plastics News (A Crain publication)