The Tool of His Trade Andrew A. Fredericks felt strongly about the best way to blast a stream of water at a fire. They called him Andy Nozzles. In training videos, speeches around the country, trade magazine articles ‹ even on the couch in his home ‹ Mr. Fredericks preached the gospel of the solid stream of water aimed hard at the source of the blaze. "He was so proud that his 9-year- old son could tell apart the different nozzles," said Diane Feldman, the managing editor of Fire Engineering, a trade magazine. It is not an academic debate. Mr. Fredericks, 40, believed that fog nozzles, which disperse water widely, were dangerous because the steam that they produced would burn firefighters who moved close to put out flames. Solid-bore ‹ those were the kind that Andy Nozzles liked. His wife, Michelle Fredericks, said that her husband relished the chance to pass on the knowledge he had gained fighting fires for 20 years, 16 of them with the New York City Fire Department, most recently with Squad 18. "It was his passion, next to me of course," Mrs. Fredericks said. "He had a passion for teaching."