Other nightclub owners say they may copy the safety announcements. Among them: the club 9:30 in Washington, D.C. In suburban Boston last week, one venue posted a sign on its door: “Due to recent tragedies, please take a moment to identify all fire exits.” Robert Plotkin, president of the National Bar & Restaurant Association, calls the here-are-the-exits speech “a marvelously well-conceived safety idea,” and says his group will discuss it at its first-ever safety conference in Las Vegas on March 26. “I can’t imagine why anybody would not [do it.]”