28 00 00 Electronic Safety and Security
28 40 00 Life Safety
28 41 00 Radiation Detection and Alarm 28 42 00 Gas Detection and Alarm 28 43 00 Fuel Oil Detection and Alarm 28 44 00 Refrigerant Detection and Alarm 28 45 00 Water Detection and Alarm 28 46 00 Fire Detection and Alarm 28 47 00 Mass Notification 28 48 00 Emergency Response Systems 28 49 00 Electronic Personal Protection Systems