Primary / Secondary School, School / University Fire sprinklers prove worth at high school fire (Hawkesbury, ON) May 3, 2013 viking210 Fire crews responded to a fire at 1:00 a.m. that began by the window of a high school classroom to find that the fire had activated the fire sprinkler which helped to suppress and contain the fire. No one was injured in the fire, and police suspect arson as the cause.