Film crew's heat lamp may have triggered LA City Hall fire sprinklers Los Angeles City Hall UPI/Jim Ruymen LOS ANGELES, April 22 (UPI) -- Los Angeles firefighters said sprinklers at City Hall may have been set off accidentally by a film crew. Los Angeles Fire Department spokesman Erik Scott said firefighters responded to a call at 2:27 p.m. on a report of one or more sprinklers being activated on the fourth floor and they quickly shut off the offending devices, the Los Angeles Times reported Monday. Scott said no carpeted floors were hit by the liquid. He said the cause of the triggering may have been a heat lamp being used by a film crew in the building.