Chapter 7

7

Fire

Protection

Systems

7

Learning Objectives (1 of 11)

• List information related to fire protection

systems that should be included in a

pre-incident plan for a protected

building.

• Compare residential sprinkler systems

to commercial sprinkler systems.

7


• Explain why it is important to “Let the

System Do Its Job” when conducting

operations in a building protected by an

automatic fire suppression system.

• Recognize the differences between wet

pipe, dry pipe, and deluge sprinkler

systems.

7


• Compare the reliability of a wet pipe

sprinkler system to dry pipe and deluge

sprinkler systems.

• Compare and contrast operations at a

sprinkler protected building with and

without obvious signs of a fire or system

operation.

7


• Describe fire department operations at a

building protected by a deluge system.

• Identify, classify, and describe different

types of standpipe systems.

7



building equipped with a standpipe

system.

• Explain discharge pressure differences

in standpipe systems and how these

differences affect operations.

7


• Describe the advantages and

disadvantages of solid bore and

automatic nozzles when operating from

a standpipe.

• Compute the pump discharge pressure

needed to supply a fire line in a high-

rise building equipped with a standpipe.

7


• Develop a list of standard standpipe equipment.

• List and describe fire protection systems other than sprinkler or standpipe systems.

• Explain fire department operations at a facility protected by a Class B foam system.

7



property protected by a total flooding

carbon dioxide system.


property protected by a total flooding

clean agent system.

7


• Define the term interlock and provide an

example of an interlock on a carbon

dioxide system.

• As it relates to company responses,

explain the possible problems with

habitual false alarm system activations.

7


• Pre-plan a building protected by a

sprinkler system.


standpipe system.

• Pre-plan a building protected by a foam

system.

7



non-water-based extinguishing system.

• Evaluate operations at a fire in a

building protected by a fire protection

system.

7

Overview

• Use of fire protection systems

– Offensive attack takes on different

character

– IC’s job made easier

– Risk to fire firefighters reduced

7

Fire Protection Systems

• Attack strategy involves properly

supporting or using the system.

• Primary tactic is to support the system.

• Fire-ground efforts should include:

– Maintaining system in full operational

status

– Laying lines for extinguishment

7

Pre-Incident Planning (1 of 2)

• Essential for buildings protected by automatic

fire suppression systems

• Should include:

– General layout of building

– Telephone numbers of owners and managers

• Information can be kept on site in a lock box

– Or on apparatus and at dispatch center

7

Pre-Incident Planning (2 of 2)

• Location and operation of various water

supply components:

– Main and divisional control valves

– Fire pump

– Fire department connections

– Water supply and hydrant water supply

– System limitations and peculiarities

7

Sprinkler Systems (1 of 2)

• Residential systems

– NFPA 13R: Residential Occupancies up to and Including Four Stories in Height

– NFPA 13D: One- and Two-Family Dwellings and Manufactured Homes

– Highly reliable

– Allow for additional escape time

– Hardware requirements are different from industrial or office systems.

7

Sprinkler Systems (2 of 2)

• Commercial-type systems

– Must meet the requirements of NFPA 13:

Standard for Sprinkler Systems

– Exceptional record in controlling fires

– Large losses of life are practically

nonexistent in buildings that are equipped

with a properly designed, maintained, and

operating sprinkler system

7

Sprinkler System Failures

• Closed valve in the water supply line

• Inadequate water supply to the sprinkler system

• Occupancy changes that render the system unsuitable

• System is shut down or otherwise out of service.

– System should be tagged (NFPA 25).

7

Types of Systems (1 of 6)

• Wet pipe sprinkler system

– One of the most reliable systems

– Reliable water supply

– Water is distributed and applied through

sprinkler heads.

– Valves control water distribution.

– Fire pumps may be needed to provide

necessary water pressure and volume.

7


• Dry pipe sprinkler systems

– Used in areas that might freeze

– Piping is filled with air instead of water.

– When a sprinkler head opens, air bleeds

out of the system.

– Water may take a longer time to reach the

fire than in a wet pipe system.

7


• Pre-action sprinkler systems

– A sensing device, such as a smoke or heat

detector, opens a valve, flooding the piping

with water.

– If a sprinkler head has also fused, water

will come out of the sprinkler onto the fire.

7


• Pre-action sprinkler systems (continued)

– Advanced warning of activation

• Computer rooms

– In some systems, both the sprinkler head

and the pre-action device must actuate for

it to operate.

7


• Deluge systems

– No water in piping or to sprinkler heads

– When activated, a valve opens, releasing

water through the open sprinkler heads

– Usually protect areas with high-challenge

fires

• Flammable liquids, conveyors moving

combustible commodities, transformers

7


• Deluge systems (continued)

– Can be equipped with manually operated

override valves

– Often located at the deluge control valve

– Fire fighters should know where these

control valves are located and how to

manually activate the system.

7

Operational Concerns

• Most common error is shutting down the

system prematurely

• ICs must be sure the fire is under

control before shutting down the

system.

7

Fire Control

• The system will usually control the fire,

but may not completely extinguish it.

– Fires that are shielded from direct water

contact

– Hand lines must be in place.

• Operations should not deprive the

system of water.

7

System Requirements

• System should have a calculated water

requirement.

– Includes enough water to support hose

streams

– The IC must be careful to avoid depleting

the system of water.

– Separate water supply

7

Working at a Sprinklered

Building with No Fire (1 of 5)

• Gaining entry

– Forcible entry may not be necessary

• Lock box

– Lock boxes identified in pre-plans

• Keys

• Potential entry locations

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• Responsible party

– It may be advisable to wait for a keyholder.

• May not be appropriate to wait if there is a

delay

• Potential fire or water damage outweighs

damage done by forcible entry

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• Forcing entry

– Property damage should be considered.

– Upper story windows

– Guidance in SOPs

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• Checking the main control valve

– Radio-equipped fire fighter should be sent

to the system riser (main shutoff).

– Two fire fighters should be assigned if the

area is hazardous.

– May remain at the valve throughout entire

operation

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• Checking the main control valve

(continued)

– Determines if system is flowing

– If not equipped with a water motor gong,

listens for water flowing through pipe

– Checks to make sure valve is fully open

7

Main Control Valves

• Sprinkler valve types, locations, and

operation should be noted in pre-plans.

• Sprinkler valve should be locked open.

– Cut or break the lock to shut down the

system.

7

Checking the Fire Pumps

• Fire pumps should be physically

checked.

– Poor practice to rely on remote annunciator

panels

– Good chance that the system is

discharging if the main pump is operating

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Monitoring the Fire Pumps

• Pumps can be manually started.

• May be able to monitor main control

valve and fire pump

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Checking for Sprinkler

Operation

• Should systematically check entire

building

• It must be verified that nothing is amiss.

7

Supplying the FDC

• A pumper with an adequate off-site

water supply should connect to the

FDC.

• The water supply for this pumper should

be large-diameter hose.

• A single 2½” (64-mm) or 3” (76-mm)

supply line to FDC is inadequate.

7

Water Supply

• Off-site water sources should be

identified in pre-plans.

• Should be covered in SOGs

7


Building with Fire

• Main objective is to support the system

while ensuring that occupants are safe

• Gaining entry

– Use the minimum force necessary.

– Time spent gaining entry will increase the

risk to occupants.

• Also causes additional fire, water, and smoke

damage

7

Checking the Main Control

Valves and Fire Pumps

• Fire fighters should be assigned to the

main valve and pump.

• Should ensure continued operation of

the system

– Provide rapid shutdown when appropriate

• Positions are critical and should be

staffed throughout the operation.

7

Control Valves

• Large systems will be equipped with

control valves on portions of the system.

• Not as prone to accidental closing as

main control valves

7

Supplying the FDC

• A pumper with an adequate off-site

water supply should connect to the

FDC.

• Department SOPs should identify

minimum water supplies and pump

pressures.

– NFPA 13 recommends a pressure of 150

psi (1034 kPa).

7

Let the System Do Its Job

• It is better to shut down a sprinkler

system too late rather than too early.

– System should be permitted to operate

until the fire is under control.

• When the system is shut down, only

small spot fires should be remaining.

– Hose lines

7

Backing Up the System

• Prepare for an offensive attack and

overhaul.

– Fire fighters should be in full PPE,

including SCBA.

7

Hose Line Use

• Hose lines should not be operated

except:

– To perform rescue operations

– To limit fire spread

– For overhaul operations after the sprinkler

system has been shut down

7

Use of Hose Lines

• May take priority if the sprinkler system

is ineffective due to:

– Damaged piping

– Malfunction

– Inadequacy

7

Ventilation (1 of 2)

• Will channel the fire and limit its

extension

• When safe, ventilation openings should

be made above the fire.

• Cooling effect of water can inhibit

upward smoke movement

– Makes it more difficult to ventilate

7

Ventilation (2 of 2)

• Recommended ventilation tactics

should be part of the pre-incident plan.

• Roof vents and draft curtains

• Overhaul requires ventilation.

– Positive or negative-pressure

• Ventilate instead of shutting down the

system to locate fire.

7

Property Conservation

• Accomplished while extinguishment is in

progress

• Extinguishment takes priority.

– Water damage dictates that property

conservation occur simultaneously

7

Placing the System Back in

Service • To return system to service:

– Replace sprinkler heads and reopen valves.

– Most codes require spare heads be kept on the

premises.

• Restoring through use of division control

valves

• Some SOPs prohibit reactivating the system.

7

Property Protected by a

Deluge System

• The tasks are basically the same for

wet, dry, or pre-action systems.

• Additional consideration: manual

operation of the deluge valve

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Deluge Systems

• Protected hazard creates extreme risks

for fire fighters.

• System operation will be obvious.

• Pre-incident planning is the key to a

successful operation.

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Deluge System Guidelines

• Check the control valve and fire pump.

– Valves should be open and pumps

operating properly.

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Operating the Deluge Valve

• Deluge can be activated manually.

• May deplete a private water supply

system

– Consideration must be given to the water

supply requirements.

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Checking Interlocks

• Deluge systems often trip interlocking

devices when activated.

– De-energize electric transformers, shut

down conveyor belts, or shut off a fuel

supply.

• Manual interlock activation

• Deluge system should control the fire

even if the interlocks do not function.

7

Let the System Do Its Job

• Shut down

– Better too late than too early

– Fire must be completely under control.

• This system will be flowing large

quantities of water, increasing the

temptation to shut it down prematurely.

7

Standpipe Equipped Building

• Not automatic fire suppression systems

– Cannot operate without human intervention

• Helpful in conducting offensive attacks

– May be impossible in high-rises if the

standpipe system is inoperative

7

Standpipe Types (1 of 3)

• Automatic dry

– Filled with pressurized air

– Water enters system when a discharge is opened.

• Automatic wet

– Most common and reliable

– Filled with water

– Provides water when the discharge is opened

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• Semiautomatic dry

– Dry standpipe

– Admits water into the piping upon

activation of a remote device

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• Manual dry

– Does not have a water supply

– System relies exclusively on a supply provided via the FDC

• Manual wet

– Filled with water connected to a water supply that maintains water in the system

– Not capable of providing water unless it is supplied

7

Standpipe Locations

• High-rise buildings

• Big box stores

– May come from sprinkler system

• Should be pre-planned

– Type and class of systems

– Variations in pressure and design

7

Pre-Connected Hose

• Poor practice to use pre-connected

hose lines

– Seldom tested or properly maintained

– Should bring own hose, nozzles, and

adapters

7

Checking Fire Pumps and

Main Control Valves

• Fire pumps should be operating and the

main control valve open.

• A properly operating system is crucial.

7

Supplying the FDC

• Much the same as for a sprinkler-protected

building

• Some systems rely entirely on pumpers to

provide water supply. The volume supplied

must be hydraulically calculated, allowing for:

– Elevation loss

– Friction loss in the hose

– Friction loss in the standpipe piping system

– Nozzle pressure

7

Friction Loss

• Standard fire-ground hydraulic

calculation should be adequate.

– 10- to 15-psi (69- to 103-kPa) friction loss

for system piping

– Not necessary to determine the exact

friction loss in system

– Pre-planning

7

Recommended Standpipe

Equipment (1 of 2)

• First-arriving engine company:

– Two 50’ (15-m) lengths of 1¾” (45-mm) or

larger diameter hose

– Smooth-bore or automatic variable-stream

nozzle

– A set of adapters, including a 2½”- to 1½”

(64- to 38-mm) reducer

7

Recommended Standpipe

Equipment (2 of 2)

• Second-arriving engine company:

– Three 50’ (15-m) lengths of 2½” (64-mm)

hose

– Variable stream or smooth-bore nozzle

• Truck company:

– Forcible entry, ventilation, and salvage

equipment as required

7

Pressure Reducing Devices

• Can cause problems for fire fighters

• Pre-incident planning and routine inspections

• Many pressure- or flow-reducing valves are field adjustable.

– Instructions should be included in pre-plans.

• Should also include arrangements to obtain special standpipe adjustment tools

7

Pressure Reducing Valves

• Pressure reducing valves

– Must be installed and maintained properly

– Ensures that systems can provide the

required volume and pressure

• With proper pre-planning and

maintenance, it should not be

necessary to field-adjust PRVs.

7

Automatic Nozzles

• Do not provide good flows at pressures

below design parameters

• Nozzle pressure of 100 psi (690 kPa)

common

– Will not provide any flow at lower

pressures.

– Should not be used on standpipes

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Smooth-Bore Nozzles

• Produce an adequate stream at low

discharge pressures

• Better choice for standpipe operations

7

Connecting to a Standpipe

Discharge (1 of 2)

• Options

– Floor below

– Fire floor

• Provided that the valve is in a stairway or other

protected area

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Connecting to a Standpipe

Discharge (2 of 2)

• Hose should be laid up the stairway

above the fire floor.

– Should be done before door is opened

– Allows for easier hose movement

7

Hose Management

• Excess hose may be a problem.

• May impede occupant egress

– Smoke conditions in the stairway from

open doors

• Two dedicated stairways

– One for fire operations, the other for

occupant evacuation

7

Non-Water Based Systems (1 of 2)

• Foam

– Surface application

– Subsurface application

– Deluge

• Halon (and other clean agents)

– Total flooding

– Local application

7

Non-Water Based Systems (2 of 2)

• Carbon dioxide

• Dry chemical

• Other inerting systems (using inert

gases to extinguish or contain a fire)

7

Specialized Systems

• Influence strategic plan

– Good working knowledge essential

• Usually activated before arrival

– IC may need to activate the systems

manually.

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Pre-Planning

• Properties protected by a suppression system should be pre-planned.

• Should note location of system components:

– Risers

– Shutoffs

– Pumps

– Agent supply containers

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System Hazards

• Suffocation hazard

– Carbon dioxide

– High concentrations of Halon

• Physical harm

– Dry chemical

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Foam Systems

• High-expansion foam systems

• Low-expansion foam systems

• Refineries and petroleum storage

depots

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High-Expansion Foam

Systems

• Rare

• Designed to protect buildings by filling

an area with foam

– Smothers the fire

– Basements

7

Low-Expansion Foam

Systems

• Storage of large quantities of flammable

and combustible liquids

• Some systems are automatic; others

require fire department support.

• Even automatic systems can be

operated manually.

7

Refineries and Petroleum

Storage Depots • Normally protect aboveground storage

tanks

• Located on or nearby the property

– Contains quantities of foam and means of

manually operating the system

• System operation differs at each facility.

– Should be familiar with the hazards and the

operation of system

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Foam

• Number one defense against flammable

liquid fires

• Nearly useless on pressurized liquids or

gases

• Will not suppress a three-dimensional

fire

– Leaking fuel

7

Carbon Dioxide Systems

• Total flooding and local application

• Uses

– In areas where preventing water damage is a

prime objective

– Where this agent is more effective than water or

dry chemical

• Extinguishes by depleting oxygen supply

• Rely on detectors for their activation

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Total Flooding System

• Depend on agent containment for a

period of time

– Ventilation shut down

– Compartment kept closed

• Very cold when discharged

– Heavier than air

– May accumulate in low or remote locations

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Halon (1 of 2)

• React quickly to suppress fire in its

beginning stages

– Limits damage to sensitive equipment

• Used in explosion-suppression systems

where deflagrations are actually

suppressed before pressure builds up

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Halon (2 of 2)

• Products of decomposition are harmful

to humans.

• Might damage some electronic

components

• Causes environmental harm

– Destroys the ozone layer

• Being phased out

7

Clean Agent Systems

• Rely on smoke detectors for activation

• Limited supply of agent must be

discharged into a confined area

– Room must remain closed

– Ventilation system must automatically shut

down

7

Dry and Wet Chemical

Systems

• Dry chemical applications

– Kitchen hoods

– Cooking appliances

– Ductwork in restaurants

– Dip tanks

– Gasoline-dispensing facilities

7

Kitchen Hood Systems

• Activated either automatically or

manually by a pull station

– For automatic operation, fusible links are

located over the area being protected or in

the ductwork.

7

Wet Chemical Systems

• Similar in design to dry chemical

systems

– Also found in kitchen hood applications

• Preferred because clean up is much

easier

• Will probably have discharged prior to

arrival

7

Total Flooding CO2 Systems

• Let the system do its job.

– If the fire is controlled, maintain chemical concentration by keeping doors closed

• No need to enter the area unless occupants failed to escape

• Have limited supply of extinguishing agent unlike sprinkler and standpipe systems

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Final Extinguishment and

Rescue

• PPE, including SCBA, must be worn if

entering room

– Area may appear to be clear yet is oxygen-

deficient.

• Clean agents may pose a threat

because of corrosive decomposition

gases.

7

Manual Activation

• Systems may be equipped with a

manual actuation device.

– Can be operated in the event automatic

sensors fail

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Abort Switch

• Systems are equipped with an abort

switch.

– Can be held to prevent agent discharge

– The IC must determine whether preventing

discharge is justified.

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Checking Interlocks

• Systems often trip interlocking devices.

– Shut down the ventilation system

– Pre-action alarms interlocked to the system

• Allow occupants time to escape

– Manually interlock activation

• Ventilation systems should be closed.

7

Local Application CO2

Systems

• Let the system do its job.

– Make sure valves are open.

– Do not interfere with system operation.

7

Checking the Interlocks

• Interlocks may shut off fuel supplies or

de-energize equipment.

• Manual operation

• Employees may be able to shut down

equipment as needed.

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Manual Activation

• Support the system by activating

manual devices.

• Generally protect Class B or Class C

hazards

• Do not depend on an enclosure.

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Backing Up the System

• Be prepared with backup equipment.

– Hose lines, foam lines, or portable extinguishers

– Augment the system and/or complete overhaul

• It is important to inspect the entire ductwork and exhaust system.

– Verify that the fire did not spread beyond the cooking appliance.

7

System Restoration

• Property owner or contractor

– Capable of recharging and resetting the

system

7

Responses to Building Fire

Alarm Systems

• False alarms are common.

– Special responses may be sent to alarm

activations.

– The high number of false alarms causes

apathy.

• Apathy lulls forces into complacency.

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False Alarms

• Poor system maintenance or improper

installation

– Assessing penalties

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Summary (1 of 2)

• ICs should take advantage of a working

fire suppression system.

– Should support and back up system

– Manual fire suppression could reduce the

effectiveness of the fixed system.

7

Summary (2 of 2)

• The key to successful operations:

– Having SOPs

– Having pre-incident plans

Chapter 7

Business

Transcript of Chapter 7