The auto industry agreed to make design changes to sport utility vehicles and pickup trucks sold in the United States so they are less dangerous to the occupants of passenger cars, according to a report in the New York Times on December 3. While the industry has for years disputed critics' contentions that the increasing prevalence of SUVs posed a serious danger to other vehicles in collisions, 15 automakers from four nations agreed to redesign their light trucks, specifically SUVs and pickups, to reduce the likelihood that they would skip over the front bumpers of cars in collisions. They also agreed to increase protection of passengers in vehicles struck in the side, most likely by making side air bags that protect heads standard equipment in vehicles sold in the United States. The changes are particularly aimed at helping people in cars survive when struck by light trucks. The changes, which are expected to cost at least $300 a vehicle and be phased in from 2007 through 2009 could save thousands of lives annually, according to projections included in a letter released Wednesday and signed by the Insurance Institute for Highway Safety and the Alliance of Automobile Manufacturers. Those groups coordinated the voluntary effort to develop the standards. The automakers also laid out a timeline to make more ambitious design and equipment changes. It included examining, over the next year, potential test procedures aimed at better measuring crash forces and protecting the chest during side-impact crashes. Over the next two years, the industry will examine the stiffness of large vehicles and the structural integrity of small vehicles, with an eye to making the former less dangerous and the latter more protective. Dr. Jeffrey W. Runge, the administrator of the National Highway Traffic Safety Administration, called the agreement a "huge" step for automakers. "They acknowledged that the responsibility is partially theirs to address compatibility," Dr. Runge said. '`We haven't always heard that." Many in the industry continue to dispute the notion that sport utilities pose a significant safety threat and have chastised regulators who have brought up the idea — most recently Dr. Runge — even though the industry's own engineers have sometimes acknowledged such a threat. Half of new vehicles will undergo the tests by 2007, or the 2008 model year, and all by 2009, or the 2010 model year. Automakers also agreed to make the frame rails and the front-end-crash-absorbing structures of SUVs and pickups overlap with at least half of the similar area on passenger cars by 2009. The height of bumpers on cars is already set by the government. The design changes will apply to vehicles that weigh up to 10,000 pounds, which would include many vehicles currently outside the regulatory system, including the Hummer H2 and the Toyota Sequoia, though not the Hummer H1.