The National Highway Traffic Safety Administration announced on Feb. 12, 2002 that it has denied a request by Bridgestone/Firestone Inc. to open a safety defect investigation into the handling and control characteristics of the Ford Explorer sport/utility vehicle (SUV) following a tread separation of a rear tire. The decision followed an extensive analysis of agency data and information provided by Firestone and Ford."The data does not support Firestone's contention that Explorers stand out from other SUVs with respect to its handling characteristics following a tread separation," said Dr. Jeffrey Runge, NHTSA Administrator.Firestone's request identified four "findings," which were based on tests of the control and stability characteristics of the Explorer and four other SUVs. Firestone provided its test data to NHTSA in several stages; the last submission was Dec. 4, 2001.Among other things, Firestone claimed that Explorers are defectively designed because they have an inadequate margin of control for an average driver following a tread separation incident. Though Firestone initially claimed this condition existed in all Explorers, it later said its contentions applied only to "1995 model year and later two-wheel drive vehicles."But the agency concluded that "the data does not support Firestone's contention that Explorers in general, or even model year 1995 and later two-wheel drive Explorers in particular, are more likely to" cause a loss of control following a rear tread separation and tire failure than other, comparable SUVs.The Firestone request focused on one specific handling factor. However, there are many other factors that determine whether a driver will be able to control a vehicle following tread separation. Moreover, the vast majority of tread separations, including many that occurred at highway speeds, do not result in crashes.The agency's analysis also referred to claims data reviewed during the Firestone tire investigation that showed there is "no significant difference in the likelihood of a crash following a tread separation between Explorer vehicles and other compact SUVs."A copy of the summary and analysis of the Ford Explorer can be found on the NHTSA website, www.nhtsa.dot.gov/hot/firestone/explorer/.The Ford Explorer decision aside, NHTSA reminds consumers that SUVs in general have a greater tendency to roll over during a crash than passenger cars. In 2000, 62 percent of all SUV fatalities were the result of rollover, compared to 22 percent for passenger cars.NHTSA's New Car Assessment Program (NCAP) rollover ratings underscore that point. Using a star rating scale of 1-5, the average 2001 SUV received three stars, compared to four stars for passenger cars. One star means the likelihood of rollover in a single vehicle crash is 40 percent; five stars means the risk is less than 10 percent. For a complete listing of rollover ratings, check the agency website at: www.nhtsa.dot.gov/cars/testing/ncap.In any situation, wearing a seat belt is the most effective way to prevent serious injury or death. In 2000, 72 percent of those killed in SUV single vehicle rollovers were unbelted.In addition, consumers are reminded that proper maintenance can reduce the likelihood of a tire failure. For further information on tire care, consult the NHTSA website or call the agency Hotline at 1-888-327-4236 for a free brochure.