WASHINGTON Sticking to its guns, the Federal Motor Carrier Safety Administration says the revised hours-of-service rules it adopted four years ago for truckers are safe and it proposed a new interim final rule that would lead to making the rules permanent.

Safety advocates, however, didnt buy the new FMCSA arguments and immediately went into federal court, asking judges to block the U.S. Department of Transportation from adopting the rule.

The controversy over truckers hours dates to 2003, when the Bush Administration increased from 10 to 11 hours the limit a commercial trucker may drive without a mandatory break within a 14-hour period.

Opponents of the change, citing the risk of driver fatigue, twice persuaded a federal court to reject implementation of the extended hours.

Much of the court concern over the revised rules centered on the methodology the FMCSA used to justify and implement the change. The court said the FMCSA procedures were inadequate.

The interim final rule was developed after new data showed trucking safety levels have been maintained since the 11-hour driving limit was adopted in 03.

"This proposal keeps in place hours-of-service limits that improve highway safety by ensuring that drivers are rested and ready to work," said FMCSA Administrator John H. Hill.

"The data makes clear that these rules continue to protect drivers, make our roads safer and keep our economy moving."

The agency noted that, in 2006, the fatality rate per 100 million vehicle miles traveled was 1.94 - the lowest rate ever recorded. Similarly, since 2003, the percentage of large trucks involved in fatigue-related fatal crashes in the 11th hour of driving has remained below the average of the years 1991 to 2002.

In 2005, the agency noted, there was only one large truck involved in a fatigue-related fatal crash in the 11th hour of driving while in 2004 there were none.

In addition, between 2003, when the 11-hour driving limit and the 34-hour restart were adopted, and 2006, the percent of fatigue-related large truck crashes relative to all fatal large truck crashes has remained consistent. And the agency estimates show that 7 percent of all large truck crashes are fatigue related.

Hill noted the agency also is working to finalize a proposed rule that would require drivers and companies with serious or repeat hours-of-service violations to track their hours of service using electronic onboard recorders.

Nevertheless, in documents filed with the U.S. Court of Appeals, lawyers for a coalition of groups, including "Parents Against Tired Truckers," asked judges to immediately enforce the courts order striking down the hours-of-service rule.

Sen. Frank Lautenberg, D-New Jersey, member of a Senate committee reviewing trucker safety, issued a statement saying the rule "allows truckers to drive for 30 percent longer each week, putting families at higher risk of an accident involving a tired truck driver."

Comments on the proposed rule are being accepted until Feb. 15 (identify Federal Docket Management System Number FMCSA-2004-19608 at www.regulations.gov).