Washington ? A new federal regulation requiring tire pressure monitors in vehicles allows automakers to use inadequate technology that will not prevent many accidents, auto safety advocates charged in a lawsuit.

The rule, inspired by accidents involving Firestone tires and issued last month, requires that vehicles built after November 2003 have a dashboard warning to alert drivers when their tires are underinflated.

Automakers can chose between two types of tire pressure monitors _ a less expensive “indirect” system that would work off the antilock braking system or a more accurate “direct” system of monitors in each wheel.

The National Highway Traffic Safety Administration originally proposed a rule that would require the direct system. But automakers want to have the option to use the indirect system and persuaded the White House to pressure NHTSA to change the rule.

The final rule allows vehicle manufacturers to use either type for three years. NHTSA will study each system and write a final rule for the monitors installed in vehicles built after November 2006.

“Two tire pressure monitoring systems are in use today, and both are effective in alerting drivers to low tire pressure, so NHTSA finalized a rule allowing both systems,” said Gloria Bergquist, a spokeswoman for the Alliance of Automobile Manufacturers. “Both systems are effective, so both systems will be used.”

The groups that filed the lawsuit Wednesday say NHTSA put the interests of the auto industry ahead of public safety when creating the rule.

“Government agencies are supposed to act rationally based on the facts,” said Russ Haven of New York Public Interest Research Group, one of three groups that filed the suit. “But NHTSA hasn’t chosen the tire system that will save more lives and reduce injuries.”

Two groups founded by consumer advocate Ralph Nader _ Public Citizen and the Center for Auto Safety _ also brought the suit, which was filed with the 2nd Circuit Court of Appeals in New York.

NHTSA officials refused to comment on the lawsuit.

The indirect system favored by many automakers would measure the rotation of all four tires and alert the driver if the rotation of one was markedly different. A tire that is low on pressure rotates faster.

Unlike the direct system, the indirect option would not identify the specific tire that was underinflated. It would not alert drivers if the tires lost air at the same rate.

Some indirect systems cannot detect pressure loss if the vehicle is traveling faster than 70 miles an hour. Also, they can take more than 10 minutes to detect pressure loss.

Some automakers already sell tire pressure monitoring systems, but they are not required by law. Congress ordered the monitors as part of strengthened tire safety laws passed in 2000 in response to the recall of millions of Firestone tires.

The tires were linked to at least 271 deaths and thousands of accidents, many of which occurred after the tread separated from the tire. Underinflation may have been a factor in some of the accidents.

A NHTSA study found that a quarter of cars and a third of light trucks are driven with at least one tire substantially underinflated.

NHTSA says pressure monitors would increase fuel economy and reduce wear on the tires. The agency also said there would be fewer crashes due to tire blowouts, immobilized vehicles or poor vehicle handling from pressure loss and hydroplaning.