21 00 00 Fire Suppression 21 01 00 Operation and Maintenance of Fire Suppression 21 05 00 Common Work Results for Fire Suppression 21 09 00 Instrumentation and Control for Fire Suppression 21 10 00 Water-Based Fire Suppression Systems 21 13 00 Fire-Suppression Sprinkler Systems 21 20 00 Fire-Extinguishing Systems Estimating 01 45 23 Testing and Inspecting Services 10 44 00 Fire Protection Specialties