Technology in Architecture Lecture 18 Fire & Life Safety Fire Protection Systems

Fire & Life Safety

Sources of Ignition Chemicals: spontaneous combustion Electrical: resistance, overloaded wiring, lightning Mechanical: sparks and friction

Products of Combustion Fire/Heat Smoke Gases  toxic, displace oxygen carbon monoxide cyanide  foam rubber hydrogen chloride  PVC hydrogen sulfide sulfur dioxide ammonia

Fire & Life Safety Objectives Protection of Life Protection of Property Continuity of Operation Codes specify minimum acceptable level of performance

Protection of Life Physical limits 2-way travel on stairs Evacuation: clear pathways, smoke free, minimum 32” entrance width, 2 hour walls/doors Physical limits 2-way travel on stairs Do not include elevators M: p.1148, T.25.3

Property Protection Increased reliability of internal systems Access for fire/life safety vehicles Increased reliability of internal systems Estimated time of arrival of fire fighters Adequate water volume and pressure Exposure protection from surrounding context Compartmentation Automatic detection/ suppression systems Structural Protection M: p.1154, F.25.7

Continuity of Operations Fire detection/suppression systems in critical areas Smoke purging systems Waterproof/water containment M: p. 1158, F.25.11

Building System Requirements Enhance Fire/Life Safety High thermal mass Adequate water pressure Overhangs on windows Reduce Fire/Life Safety Open plan Forced air systems Electric lighting only Sunscreens Non-operable windows Insulation Acoustical materials

Smoke Management Strategies Confinement Fire walls Smoke barriers Dilution Pressurized stairwells Exhaust Large atria HVAC Pressurize building Automated Ventilating Hatches

Water Management Strategies + cools smothers fire removes heat/oxygen - damages contents conducts electricity dilutes oil changes to steam

Water Management Strategies Water Sources Standpipes  siamese connection to outside Hose Cabinets  siamese connection or house tank Sprinkler Systems  siamese connection or house tank

Water Management Strategies Sprinkler Head Types Semi-Recessed Recessed Pendant Upright Sidewall

Water Management Strategies Hazard levels Light Ordinary Extra-hazard M: p. 1166, T.25.7

Water Management Strategies Sprinkler spacing orientation sprinkler type hazard level M: p. 1169, T.25.9

Fire Protection Systems

Fire Protection Systems Sprinkler System Types Wet-pipe Dry-pipe Preaction Deluge

Wet-pipe Systems Water in pipe Sprinkler activated Sprinklers closed Used in areas with temperature> 40ºF M: p. 1172, F.25.18

Dry-pipe Systems Compressed air or nitrogen in pipe Sprinkler activated Sprinkler closed Used in unheated areas Valve in heated enclosure M: p. 1177, F.25.23

Preaction System Air in pipe Minimal air pressure Separate detectors Sprinklers closed Used in water-damage sensitive areas Delay in filling allows time to find/fight fire M: p. 1178, F.25.24

Deluge System Air in pipe Separate detectors Sprinklers open Used where extremely rapid fire spread expected M: p. 1179, F.25.25

Non-Water Suppression Systems Halogenated Gases  now illegal Foams Carbon Dioxide (CO2) Clean Agent Gases Portable Fire Extinguishers

Design Considerations Head location/type Uniform coverage Symmetry Connectivity M: p. 1173, F.25.19

Example Layout