Water-Based Fire Protection
Systems & Equipment
Water as an Extinguishing Agent
The great majority of fires are extinguished
using water.
Water is usually available at or near the fire
scene and has special physical properties well
suited for fire fighting.
Extinguishing Properties of Water
Cooling depends on how quickly water is applied,
how much is applied and what form.
Water absorbs the most heat when it is converted to
steam and that is more easily performed from droplets.
Smothering foaming agent is usually added to the
water.
Emulsification Cools surface of flammable liquids
and prevents release of flammable vapors.
Dilution for fires in water-soluble flammable
materials.
Electrical Conductivity of Water
Water in its natural state contains impurities
that make it conductive.
If water is applied to fires involving electricity,
continuous circuit may be formed and shock
applier.
Water-based foam agents are very conductive.
Using Water on Special Hazards
Chemicals
Combustible Metals
Radioactive Materials
Gases
Combustible & Flammable Liquids
Cooling agent
Mechanical tool
Displacing medium
Increased Friction Loss
Sediment and Debris Incrustation from Mineral Deposits
Types of Fire Hydrants
Dry Barrel
Stem Nut
Drain Hole
Operating Stem
Main Valve
Wet Barrel
Operating Stem
Automatic
Check
Hose Outlet
And
Valve Seal
Hydrant Inspection & Maintenance
Obstructions preventing
pumper-to-hydrant
connections
Outlets facing proper
direction for pumper-to-
hydrant connections
Sufficient clearance
between the outlets and
ground for hose
connections
Damage
Rust or corrosion
Hydrant caps stuck in place
with paint
Operable operating stem
(easily turned)
Obstructions (bottles, cans,
rocks) inside hydrant
restricting water flow
Sprinkler System Design & Operation
Series of sprinklers arranged to automatically
distribute enough water to extinguish or check fire.
Water is supplied to sprinklers through a piping
system.
Systems sprinkler heads discharge water after a cap
or plug is released by a heat-responsive element.
NFPA 13 Standard for the Installation of Sprinkler
Systems, but other NFPA standards also have a
direct bearing on certain phases of sprinkler
protection.
Sprinkler System Advantages
Most reliable
Most effective
(control 96% of fires in sprinkler-protected
buildings)
Less business interruption
Less water damage
Enhance life safety
Reduce insurance costs
Parts of a Sprinkler Head
Frame
Arms
Lever
Arms
Valve
Cap
Deflector
Release
Mechanism
(Fusible Link)
Releasing Mechanisms
Fusible Link
(Standard)
Chemical
Pellet
Frangible
Bulb
Fusible Link
(Quick
Response)
Sprinkler Head Activation
How the Bulb Works
1. Heat from fire
heats liquid in
bulb & breaks.
2. Releases cap.
3. Water is released
onto diffuser.
4. Water puts out
fire.
Sprinkler Head Temp Ratings
Sprinkler heads are designed with
temperature ratings ranging from 135
o
F to as
high as 500
o
F.
Ratings of 165
o
F are common for use in
buildings maintained at normal, constant
temperatures.
Sprinkler Bulb Colors
Temperature Rating
(
o
F)
Temperature
Classification
Glass Bulb Color
135-170 Ordinary Orange or red
175-225 Intermediate Yellow or green
250-300 High Blue
325-375 Extra High Purple
400-475 Very Extra High Black
500-575+ Ultra High Black
Sprinkler Head Designs
Pendant
Sidewall
Upright
Wet Pipe Sprinkler System
Uses a piping system containing water under
pressure at all times.
When a fire occurs, individual sprinklers are
activated by heat, and water flows through
those sprinklers immediately.
Generally used wherever there is no danger
of the water in the pipes freezing and no
special conditions requiring one of the other
systems.
Wet Pipe Sprinkler System
Dry Pipe Sprinkler System
Sprinklers attached to piping which contains air
or nitrogen under pressure.
When a sprinkler is opened by heat, the
pressure is reduced to the point where water
pressure on the supply side can force open the
valve.
Then water flows into the system and out any
opened sprinklers.
Dry Pipe Sprinkler System
Dry Pipe Demonstration
Preaction System
Contain air in the piping that may or may not
be under pressure.
When a fire occur, a supplementary fire
detecting device in the area is activated.
This opens a water control valve which permits
water to flow into the piping system before a
sprinkler is activated.
When sprinklers are opened by heat of the fire,
water flows through the sprinklers immediately
same as a wet pipe system.
Situations In Which
Sprinklers Are Effective
Preventing fire spread upwards in multiple-
story buildings.
Protecting the lives of occupants in other
parts of the building.
Sprinkler Demonstration Video
Start at 3:00
Situations In Which Sprinklers May Not
Be Effective
Fires too small to activate sprinkler system.
Smoke reaches occupants before sprinkler
system activates.
Sleeping, intoxicated, or handicapped
persons occupy fire building.
