ACTIVE FIRE PROTECTION SYSTEMS OVERVIEW. Fire Protection Systems

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1 ACTIVE FIRE PROTECTION SYSTEMS OVERVIEW ICC: International Code Council codes are updated on a 3-year revision cycle Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 1 Fire Protection Systems Passive systems (generally architectural) Fire egress paths Fire rated constructions Spray-on fireproofing Areas of refuge portable extinguishers: previously discussed are an active, architectural system Active systems (primarily mechanical & electrical) Fire sprinklers Fire alarms Standpipes today s focus Other (specialized) systems Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 2 1

2 Standpipe and Hose Systems The left side of image big help System is designed by a mechanical engineer It is a manual system Going beyond first aid, this system provides an easily accessible and substantial water supply for fire extinguishment (big gesture versus small gesture) Code-optional OR mandatory (building type determines) System design issues Class of service (based upon intended users) Outlet locations (hose distance / spray coverage by code) Water supply help Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 3 Standpipe and Hose Systems Classes: I (for trained users; has large valve, no hose) II (for untrained users; smaller valve, with hose) III (for both user groups) Components: Water supply (may be volumetrically significant) Generally vertical pipe runs (easy to coordinate) Valves (and perhaps hoses/cabinets) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 4 2

3 Standpipe and Hose Systems non-freezing climate typical installation (pipe hidden) Class I bring your own hose; firefighters do so Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 5 Standpipe and Hose Systems casual user casual or trained user Class II element Class I element Class II Class III Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 6 3

4 Standpipe and Hose Systems custom architectural enclosure in an atrium with no opaque walls a solution that pushed the letter of the code, while meeting the intent Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 7 Standpipe/Hose & Extinguisher any ideas? oops! one-stop extinguishment stations with issues Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 8 4

5 Automatic Sprinkler Systems Automatic fire sprinkler system Designed by a mechanical engineer (or, more often, by a sprinkler contractor) Is an automatic system (no operator required) Code-optional OR mandatory (building type determines) Common in many building types (becoming increasingly common) System design issues System type (several) Sprinkler head locations and types Water supply a good place for a duct Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 9 Automatic Sprinkler Systems Types: Wet pipe by far the most common Dry-pipe where freezing of water is possible Deluge for high-hazard applications Pre-action where concern over water damage rules Components: Sprinkler heads Piping network (to connect heads to water supply) Water supply Appurtenances: control valves; alarms; drains; etc. Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 10 5

6 Wet-Pipe Sprinkler System Pipes are always filled with water Heat from a fire opens a sprinkler head by causing the head to fail (a metal link melts or a glass bulb breaks) Usually only one or two heads will open (those that experience higher temperatures near the fire) Water flows until it is shut off (usually manually) The open ( broken ) sprinkler head is replaced The system is reset Options: A wide variety of conventional sprinkler heads Recessed (flush) sprinkler heads Auto-shut-off heads (no longer manufactured due to quality control issues) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 11 Wet-Pipe Sprinkler System NFPA Fire Protection Handbook (20 th ed.) all pipes are filled with water; opening of a sprinkler head triggers water flow Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 12 6

7 Dry-Pipe Sprinkler System Pipes are not filled with water (but are pressurized with gas or air) Heat from a fire opens a sprinkler head Usually only one or two heads open Pressure drop in the piping (as air escapes from open head) opens a dry-pipe valve water valve (the dry-pipe valve) Water fills the piping network and then exits through the open sprinkler head(s) and sprays onto the fire Water flows until it is shut off The open sprinkler head is replaced System is reset news.thomasnet.com Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 13 Dry-Pipe Sprinkler System NFPA Fire Protection Handbook (20 th ed.) pipes in protected space are filled with inert gas/air; an opening sprinkler head triggers the system by releasing the gas, which reduces pressure and allows water to flow into the pipes and then out through the open sprinkler head Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 14 7

8 Deluge Sprinkler System Pipes are not filled with water (or gas) All sprinkler heads are pre-opened A signal from a fairly sensitive detection device mechanically opens a water valve Water fills the pipes and flows from all heads objective is to ensure that a very dangerous fire situation is quickly defused Water flows until it is shut off System is reset Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 15 Deluge Sprinkler System NFPA Fire Protection Handbook (20 th ed.) pipes in protected area are empty; a detector signal triggers the system, allowing water to enter pipes and flow from all sprinkler heads (which are already open) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 16 8

9 Pre-Action Sprinkler System Pipes are not filled with water All sprinkler heads are of standard type (they are normally closed) A detection device opens a water valve when it senses a triggering event (such as smoke) Water fills the pipes Water will only flow from a sprinkler head if it is opened by heat from a fire Water flows until shut off (or, more logically, detectors close the control valve) System is reset Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 17 Pre-Action Sprinkler System NFPA Fire Protection Handbook (20 th ed.) pipes in protected area are empty; a detector signal triggers the system, allowing water to enter pipes and flow into piping network; heat from a fire may then open a sprinkler head; accidental damage to a head will not result in water flow Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 18 9

10 Sprinkler Heads Basic types Upright Pendant Sidewall Tweaks Recessed heads Self-closing heads (taken off market) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik Sprinkler Heads frangible bulb fusible link The typical sprinkler head Is activated by heat (temperature) Opens when a triggering action occurs A frangible bulb breaks (color indicates temperature setting) A fusible link melts Water flows when the head is opened Water is manually shut off Once activated, head must be replaced Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 20 10

11 Sprinkler Heads pendant with frangible bulb >> Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 21 Sprinkler Heads pendant with fusible link >> Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 22 11

12 Sprinkler Heads sidewall with >> frangible bulb Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 23 Sprinkler Heads recessed head ( flush ) ^^ usually selected in order to reduce visual impact Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 24 12

13 Quality Control? minimizing visual impact not so much with this one Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 25 Typical Sprinkler Piping Installation often designed and installed by a contractor; not an engineer thus the sprinklers may not appear on project drawings, reducing coordination (BIM) opportunities Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 26 13

14 Atypical Sprinkler Piping Installation hopefully, a retrofit project Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 27 Exterior Sprinklers why? type? Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 28 14

15 Fire Protection Water Supply The required capacity (based upon flow rate and flow duration) of fire protection water supply is specified by building codes (based upon NFPA standards) NFPA = National Fire Protection Association NFPA publishes the National Fire Codes (an extensive set of standards, which includes NFPA 101 the Life Safety Code) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 29 Fire Protection Water Supply governed by NFPA 13; one of numerous NFPA standards Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 30 15

16 Fire Protection Water Supply NFPA 13 excerpts dealing with sprinkler system water supply requirements Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 31 Water Supply Approaches (applicable to fire protection and potable water systems) Direct upfeed (the street main provides necessary pressure; only feasible for low-rise buildings with adequate mains pressure) Gravity downfeed (water is pumped to a rooftop storage tank and then flows down by gravity) Pumped upfeed (variable speed pumps are used to provide water lift upon demand) Hydro-pneumatic tanks (water tanks are pressurized with air to permit upfeed an alternative to pumped upfeed) Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 32 16

17 Water Supply Approaches direct upfeed lift limited by water main supply pressure; must provide lift and adequate residual pressure to deliver water through hose/nozzle or sprinkler head water main Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 33 Water Supply Approaches tank gravity downfeed no height limit; pump provides lift and gravity provides adequate residual pressure; control is simple; has architectural and structural implications pump water main Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 34 17

18 Water Supply Approaches pumped upfeed no height limit; pump provides lift and adequate residual pressure; requires sophisticated controls (to provide water for one or two or three or four sprinkler heads); has replaced gravity systems; will be zoned in a tall building water main pumps Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 35 Water Supply Approaches hydropneumatic system no height limit; air pressure provides lift and adequate residual pressure; control is simpler than direct upfeed, but system is more complex (and requires a storage tank) air compressor water main pump Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 36 18

19 Sprinkler System Artifacts siamese connections a fire department connection to the building fire protection water system; a fire truck can pump water into a building from street hydrants using such connections Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 37 Other Fire Protection Systems High expansion foams Inert gas flooding system Others Halon (shown here) is a serious greenhouse gas and has been replaced by less problematic compounds used where a conventional water system won t work Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 38 19

20 Inert Gas Fire Protection Systems langemachinery.en.ecplaza.net Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 39 fire protection systems: because fires happen Ball State Architecture ENVIRONMENTAL SYSTEMS 2 Grondzik 40 20