At ~ 8:52 AM, Westmorland 911 dispatched Station 20 (Murrysville VFC) to assist Station 9 (Level Green VFD) for a Residential Automatic Fire Alarm (AFA) at a home on Meadowbrook Road, Penn Township. Also dispatched to assist Station 9 were Station 7 (Paintertown VFD), Station 86 (Trafford VFD), and Station 87 (Harrison City VFD). Station 20 was preparing to depart station with Engine 20 (3 firefighters including Lieutenant 20), when Assistant Chief 9 cancelled all responding units after finding the AFA had been set off by accident.