(Bloomberg) – Owners of about 313,000 Honda and Acura vehicles from the 2001 to 2003 model years should have defective Takata Corp. air bags replaced immediately because new tests show the devices in those models have a far greater risk of rupturing, U.S. regulators said.

The National Highway Traffic Safety Administration (NHTSA) said in a statement Thursday that the Honda and Acura models affected were recalled between 2008 and 2011, with about 70% of them already repaired. The agency said it and Honda are trying to alert owners of the remaining vehicles from that group to avoid further deaths or injuries.

Heat and humidity

In lab tests, the air-bag inflators have rupture rates as high as 50%, especially when exposed to heat and humidity, NHTSA said. Test on similar Takata air bags that don't have the same manufacturing defect rupture less than 1% of the time, according to the agency.