WATER FOR FIRE PROTECTION (Chapter 26)

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WATER FOR FIRE PROTECTION (Chapter 26)

• Basic factors of fire
• Rapid oxidation of combustible materials
• A combination of oxygen, fuel, and heat is
  required to start a fire.
• Classification of fire hazards
• Classification of occupancy hazards

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WATER FOR FIRE PROTECTION (Additional information)

• Objectives in fire safety
• Protection of life
• Evacuation of people the time interval between
  detection of fire and arrival of fire fighters.
• Providing adequate number of fire exits and
  clearly defined access (i.e. corridors, hallways,
  etc.) to exits.
• Absolute minimum width of an exit access is 28".
• In order to accommodate adults using various
  walking aids, corridors should be at least 36"
  wide.
• The standard unit of exit width computation is
  22" (i.e. 22" 1 exit unit).
• Exit Width Units Floor area of the building in
  sq. ft./(occupant density in sq. ft./person)
  (Capacity per unit of exit width)

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WATER FOR FIRE PROTECTION (Additional information)

• Minimum exit requirements
• Basement 2
• Every building floor 2
• Building with 50 occupants or more 2
• Building with 500 occupants or more 3
• Building with 1,000 occupants or more 4
• Maximum distance of a fire exit from any part of
  the building
• 100 to 200 ft. for unspriklered spaces
• 150 to 300 ft. for sprinklered spaces.
• Protection of property
• Continuity of operation

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WATER FOR FIRE PROTECTION

• Methods for fire detection
• Methods of fire control
• Standpipe systems
• Automatic sprinkler systems
• Piping design
• Hydraulic method Hazen-Williamson formula
• Use of piping schedule
• Flow rate of sprinklers
• Sprinklers on a branch line
• Protection area per sprinkler
• Maximum spacing between sprinklers

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DESIGN OF SPRINKLER SYSTEMS (Additional
information)

• Residual pressure of the sprinkler system
• pressure remaining in a system while water is
  being discharged from the outlets
• sprinkler systems are usually designed for a
  maximum working pressure of 175 psi.
• Density of Water Flow (D)
• required water flow from a sprinkler in gallons
  per square foot of area of operation
• Light hazard 0.07 to 0.1 gpm/sq.ft.
• Ordinary hazard 0.1 to 0.2 gpm/sq.ft.
• Extra hazard 0.2 to 0.4 gpm/sq.ft.
• Size of sprinklers
• Find required flow rate (in gpm) of a sprinkler
  (Density of water flow Maximum coverage)
• Find out k-factor to determine the size of the
  sprinklers
• Q K ?p, where Q flow rate in GPM, K flow
  constant of sprinklers, p residual pressure in
  psi
• Determine the size of the piping system
• Use the method for sizing water supply pipes
  (either pipe sizing formula or piping schedule)

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Sprinkler head sizes (Additional information)
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WATER FOR FIRE PROTECTION (Additional information)

• Water demand for fire suppression
• Area of Sprinkler Operation (ASOP)
• Only a small part of the sprinkler systems need
  to be operated during the early stage of fire.
  Codes, therefore, require only a small area of
  the building to be calculated for simultaneous
  flow demand. This area, called the area of
  sprinkler operation (ASOP), for different hazard
  classifications is as follows
• Light 1500 - 3000 sq. ft.
• Ordinary 1500 - 4000 sq. ft.
• Extra 2500 - 5000 sq. ft.

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WATER FOR FIRE PROTECTION (Additional information)

• Density of Water Flow (D)
• required water flow from a sprinkler in gallons
  per square foot of area of operation
• Light hazard 0.07 to 0.1 gpm/sq.ft.
• Ordinary hazard 0.1 to 0.2 gpm/sq.ft.
• Extra hazard 0.2 to 0.4 gpm/sq.ft.
•  Hose Stream Demand (HSD)
• water demand of hoses, both inside and outside
• Light hazard 100 gpm
• Ordinary hazard 250 gpm
• Extra hazard 500 gpm
• Overage Factor (OVF)
• Usually 1.1
• Total Water Demand in gpm ASOP D OVF HSD

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Other methods of fire suppression

• Carbon dioxide
• Dry chemicals
• Foam systems
• Halogenated agents