Government Office, Government/Military Sprinkler system keeps damage to a minimum after fire at City Hall (Fitchburg, MA) July 26, 2012 viking210 City Hall on Main Street will be open for business as usual after a fire about 5 this morning in the Veterans Room on the first floor. Deputy Chief John C, Curran said the cause of the fire was a problem with the heating/air conditioning unit. He said a sprinkler in the room activated and doused the fire, keeping the damage minimal. No one was hurt.