Chapter 12

Protective Systems

Introduction• Protective systems help guard lives

and property• Detection systems detect presence

of fire and alert occupants and/or fire department

• Suppression systems help firefighters in controlling fires

• Detection systems are varied• Three systems can be combined to

form protective ensemble12.2

Detection Systems

• Designed to notify people• Simple systems warn person to

recognize danger• Complex systems use series of

devices to automatically detect event and initiate alarm

12.3

People or Manual Systems

• People can alert other people and call fire department after discovering a fire

• Requires a person to discover a fire and pull the alarm

• Two typical problems:– Person must be present, awake, and alert– Systems are local only

12.4

Heat Detectors

• Detect heat of fire at fixed temperature or as rising temperature builds at rapid rate

• Can be used as part of a suppression system

• Slow to detect fires• Inexpensive with low rate of false

alarms• Spot type or line type

12.5

12.6

Figure 12-1 Rate-of-rise heat detector.

Smoke Detectors

• Smoke and toxic gases are leading killers of people in residential structure emergencies

• Most prevalent automatic detection system

• Can be hard wired, battery operated, or a combination

• Ionization detectors are the most common type

12.7

Gas Detectors

• Designed to find presence of certain gases prior to reaching a concentration

• Carbon monoxide detectors for home are popular

• CO detectors function using several different methods

• Most provide an early warning alarm

12.8

Combination Smoke/Carbon Monoxide Detectors

• Simplify things for the builder• Can make discerning situation more

difficult for firefighters– Detector manufacturers have added

different alarms and colored lights for each situation

– Excited homeowner may not correctly distinguish between the two

– Some manufacturers have added voice prompts 12.9

Flame Detectors

• Detect flames or lightwaves– Ultraviolet– Infrared– Combined ultraviolet-infrared

• Very sensitive and quick to alarm• Used to protect petroleum and chemical

facilities

12.10

Sprinkler Systems

• Designed to automatically distribute water through sprinklers

• Usually in the ceiling• Most sprinkler heads detect heat• Highly effective

12.11

Sprinklers and Life Safety

• Originally designed in late 1800s• Intent was to protect business and

industrial property• Almost 100 percent effective• Failure due to two reasons:

– Improper maintenance– Inadequate water supply

12.12

Sprinkler Head Designand Operation

• Sprinkler heads are the key component• Deluge-type have separate detection

devices• Come in many designs:

– Old-style sprinklers– New style or standard sprinklers

• May require:– Corrosion-resistant heads– Dry head with extension piping– Rack storage head, decorative head

12.13

Types of Sprinkler Systems

• Some sprinkler systems protect:– Homes or apartment buildings– Buildings with highly sensitive electronic

equipment– Homes and businesses in areas subject

to harsh winter conditions

12.14

Specialty Sprinkler Systems

• Include some combination-type sprinkler system and systems that cannot meet standards

• May have inadequate water source or supply

• Fire departments must be familiar with limitations and intended protection strategy

12.15

Wet Pipe Systems

• Automatic sprinklers attached to pipes with water under constant pressure

• Quick response• Simplest sprinkler system in design

and operation

12.16

Figure 12-11 Wet pipe sprinkler system.

Dry Pipe Systems

• Air under pressure replaces water• Uses a dry pipe valve• More complex in design than a wet pipe

system• Harder to return to service after activation

12.17Figure 12-14 Dry pipe system schematic.

Deluge Systems

• Designed to protect areas that may have fast-spreading fire

• Must interface with a detection system

• Causes tremendous quantities of water to flow

12.18

12.19

Figure 12-16 Deluge system schematic: 1, OS&Y valve; 2, deluge valve with basic trim; 3, solenoid valve and electric actuation trim; 4, pressure alarm switch; 5, water motor alarm; 6, spray nozzles or open sprinklers; 7, deluge releasing panel; 8, electric manual control stations; 9, fire alarm bell; 10, trouble horn; 11, heat detectors. (© Copyright Simplex Grinnell. All rights reserved.)

Pre-action Systems

• Similar to dry pipe and deluge system• Closed piping and heads with air

under no or little pressure• Water flows from separate fire

detection system• Found in computer rooms, museums,

or buildings storing historical items

12.20

12.21

Figure 12-17 Pre-action system schematic: 1, OS&Y valve; 2, deluge valve with basic trim; 3, check valve; 4, solenoid valve and electric actuation trim; 5, water pressure alarm switch; 6, 1.5-psi low air pressure alarm switch; 7, 1.5-psi supervisory air pressure control; 8, water motor alarm; 9, automatic sprinklers; 10, deluge releasing panel; 11, electric manual control stations; 12, fire alarm bell; 13, trouble horn; 14, heat detectors. (© Copyright Simplex Grinnell. All rights reserved.)

Residential Systems• Smaller and more affordable version

of wet or dry pipe systems• Water supply combined with

domestic water supply• Designed for one or a few heads• Use lighter and smaller piping• First suppression system to use

plastic piping• Some use antifreeze

12.22

Sprinkler SystemsConnections and Piping

• Comprise most of the components of sprinkler system

• Water comes from public or private water

• Secondary source supplied via fire department connection

• Firefighter should be able to connect supply line to fire department connection 12.23

Control Devices forSprinkler Systems

• Three main control devices:– Outside stem and yoke valve (OS&Y)– Post indicator valve (PIV)– Wall indicator valve (WIV)

12.24

Returning SprinklerSystems to Service

• Most departments no longer provide testing or service

• Once fire is extinguished, firefighters should leave at least one charged hoseline in place

• Simplest and quickest way to stop water flow from sprinkler head is to insert a stop

• Once system is shut down, heads may be replaced

• Fire watch established until system is restored

12.25

12.26

Figure 12-25 Sprinkler tongs and wood wedges stopping sprinkler flow.

Standpipe Classifications

• Designed to allow firefighters to fight fires in larger buildings by pre-piping water

• Classified according to intended user– Class I– Class II– Class III

• Differentiated based on water supply

12.27

12.28

Figure 12-27 Class II standpipe system.

Standpipe SystemConnections and Piping

• Range from very simple to highly complex– Piping– Outlets with hose and other attachments– Valves– Fire department connection– Any monitoring devices

• Standpipe valves similar to vales used on sprinkler systems

12.29

Alarms for Standpipesand Sprinklers

• Found in most sprinkler and standpipe systems

• Most protective systems require monitoring to prevent tampering

• Monitoring alarm company notifies fire department about fires– Company responds on its own to

tampered alarms

12.30

Other Protective Systems• Many other types are used today• Some are rather simple:

– Grill– Fryer– Ductwork

• Others are extremely complex and designed to prevent or suppress an explosion

• All firefighters responding need to be familiar with operation of complex systems

12.31

Local Applicationand Hood Systems

• One of the most common types of protective systems is a local application system

• Protects only a certain portion of building• Also used in:

– Laboratory hoods– Paint booths– Small hazardous locations

• Use heat-sensitive device or manual switch for activation

12.32

Total Flooding Systems

• Used to protect an entire area, room, or building

• Discharges an extinguishing agent• Effective as long as proper amount

discharges

12.33

Fire Department Operationswith Protective Systems

• Standpipe, sprinkler, and other protective systems are part of fire department strategy plan

• Strategy recognizes community’s hazards

• Protective systems required when properties or processes create hazards beyond certain limits

• Protective systems can be separate components 12.34

Standpipe Operations• Start with establishing water supply to fire

department connection• Pump operator should immediately charge

standpipe system• Personnel should check annunciator panel• Fire crews should stop at least two floors

below reported fire level• Personnel should have full protective

equipment, standpipe pack, and forcible entry equipment

12.35

Sprinkler System Operations

• Begin with investigation of building• First arriving officer check

annunciator panel• Pump operator should charge

sprinkler system• Personnel should advance hoseline

into fire area• If no fire is found, officer may direct

firefighters to stop sprinkler flow12.36

Detector ActivationOperations

• Histories of false alarms have caused firefighters to take a less than ready approach

• Firefighters must treat all fire alarm activities as an actual fire

• Firefighters should dismount wearing full PPE, SCBA, and carry necessary tools and radio

• At commercial structures, first arriving crew checks annunciator panel

• Do not turn off alarms prematurely12.37

Operations for OtherProtective Systems

• Local SOPs should address operations for:– Total flooding– Foam– Dry chemical– Other unique systems

• Clean up of foam is not responsibility of fire department, but occupants must be warned

• Activation of suppression systems may cause secondary damage

12.38

Lessons Learned• Protective systems designed to

automatically detect or suppress a fire– Apply water or other extinguishing agents

• Sprinkler systems used for detection and suppression– Apply water or foam

• Standpipe systems facilitate manual fire suppression

• Fire department operations at buildings with protective systems outlined in SOPs

12.39