WASHINGTON - The federal government is proposing that cars and trucks be built so that they leak almost no fuel when rear-ended by another vehicle at 50 mph.
Current standards require a 30-mph rear-impact crash test with a flat barrier.
The National Highway Traffic Safety Administration estimates the tougher standard would save up to 21 lives annually and prevent many more serious burn injuries.
'Vehicle fires only occur in about 1 percent of (tow-away) crashes, but their consequences are severe,' said Dr. Sue Bailey, NHTSA administrator.
Automakers generally have supported improving the test procedures but will need to examine the proposal before commenting, said Gloria Bergquist, vice president of the Alliance of Automobile Manufacturers.
Noting that the proposal comes at the same time NHTSA is preparing to implement a new wide-ranging vehicle safety law, Bergquist said, 'The bar keeps getting higher.'
NHTSA will accept comments on the proposal for two months. Then the agency is likely to adopt the final rule.
The proposed new rear-crash test has been more than five years in the making. General Motors is funding some of the research related to the proposal. GM agreed to the funding in a 1994 settlement by which it avoided a recall of full-sized pickups. Critics blamed their sidesaddle gasoline tanks for fires in crashes.
Under the NHTSA proposal, vehicles also would be checked for fuel leaks when they undergo existing 33.5-mph side-impact tests that measure occupant protection. A separate 20-mph side impact that has been used for testing fuel systems would be eliminated.
$5 PER VEHICLE
The proposed rear crash test would be much tougher than the mere increase in speed from 30 mph to 50 mph suggests, NHTSA officials said. The force of crashes increases exponentially with speed. Also, the test would have a carlike object, not a flat barrier, hit the test vehicle at a slight offset - toward the side where the fuel filler is located.
NHTSA researchers found that some of today's vehicles would pass the new test without changes. The agency estimates the proposal would require changes in about 7 million vehicles a year, at a cost of about $5 per vehicle.
The requirement that manufacturers prevent fuel spillage in crashes was one of the first vehicle safety rules adopted by the federal government three decades ago.
The current version requires that no more than five ounces leak in the first five minutes after impact and no more than one ounce in any one minute for 25 minutes after that. NHTSA proposes to keep the leakage limits the same.