The number of vehicle recalls involving problematic airbags is up this year, Dow Jones Newswires reported, citing data from the National Highway Traffic Safety Administration (NHTSA), according to the Web site www.just-auto.com/. So far in 2004, more than 1.4 million recalls in the U.S. are related to airbag problems, according to data the news agency culled from the NHTSA Web site. In 2003, more than 350,000 recalls were related to airbag problems. Beginning in the 2004-model year, NHTSA mandated that vehicle makers install "smart" airbag systems, which are supposed to help determine the size of the seat occupant and deploy the airbags with less force if the passenger was smaller. Dow Jones noted that, in 2002, automakers asked NHTSA for more time to put in the airbag systems. The agency responded by scaling back the phase-in period, calling for 20 percent to have the systems rather than 35 percent. NHTSA spokesman Rae Tyson told Dow Jones the agency closely monitors airbag systems and the technology is getting more scrutiny since the new regulations went into effect. Still, he said he's not sure why the number of recalls related to air bags has gone up this year. "You get increasing numbers in the fleet that have got airbags," he reportedly said. "And airbags have gotten much more complex." Dow Jones said many of the recalls this year involve wiring problems that could result in the airbags not going off when needed. "That's a major safety defect," Joan Claybrook, president of consumer advocacy group Public Citizen, told the news agency. "Non-deployment is the ultimate failure." Carmakers are putting more and more technology on vehicles, making their electronic systems increasingly complex, Claybrook told Dow Jones, and that could be affecting overall quality.