An alliance of automakers has warned that many of its members will be unable to meet a government mandate requiring a percentage of all new vehicles sold after September 2003 be equipped with so-called "smart" passenger-side air bags, according to a Reuters report. Reuters said that the car industry is attempting to meet federal rules requiring sensors that detect whether a child weighing less than 56.5 pounds is sitting in the passenger-side front seat and turn the airbag off to prevent injury. The regulations follow the death of more than 200 people, mostly children, from airbags in the United States, Reuters added. According to Reuters, the National Highway Transportation Safety Administration (NHTSA) has proposed that 20 percent of all vehicles sold by a car maker after September 2003 be equipped with the airbags, down from its original goal of 35 percent. But, Reuters said, the Alliance of Automobile Manufacturers said in a letter to the NHTSA last week that many car makers would be unable to meet the regulations because of the technology in the airbags. The alliance proposed that NHTSA cut the requirement to 10 percent of vehicles sold.