A popular type of lightweight police vest failed to stop a bullet in nearly 6 of every 10 tests, says a Justice Department study that resulted in immediate changes in federal guidelines, reports the New York Times. Ballistic tests on 103 vests containing a fiber known as Zylon produced acceptable safety results for just four vests. The shooting deaths of at least two officers have been blamed on the vests.
Police armor using Zylon, patented by a Japanese company, became popular about a decade ago as an alternative to hotter, bulkier vests. The material is found in more than 240,000 vests bought by U.S. police departments. Many departments have stopped using Zylon vests in the last two years in light of increased safety concerns and lawsuits against manufacturers. “We expected the Justice Department to find some level of deficiency in these vests, but this level is startling,” said Jim Pasco of the Fraternal Order of Police, which first alerted officials to potential dangers in Zylon vests.