Describe Industrial Fire Detection and Alarm Systems

Describe Industrial Fire Detection and Alarm Systems
Training Module
Describe Industrial
Fire Detection and
Alarm Systems
FIRE
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Human Development
Consultants Ltd.
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Describe Industrial Fire Detection
and Alarm Systems
© 2004 and 2012 by HDC Human Development Consultants Ltd.
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This publication is designed to provide general information regarding the subject matter covered. Care
has been taken to ensure the accuracy of the information and that the instructions contained in this
publication are clear and reflect sound practice. The user understands that HDC is not providing
engineering services. The user understands that any procedures (task steps) that are published or
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ISBN 1-55338-030-4
Canadian Cataloguing in Publication Data
1. Fire detectors. 2. Fire alarms. I. HDC Human Development Consultants.
TH9271.D49 2003 628.9’225 C2003-905903-0
This training kit consists of the following parts:
Training Module and Self-Check
Blank Answer Sheet
Knowledge Check and Answer Key
Performance Check
Published by HDC Human Development Consultants Ltd.
Published in Canada
HDC Human Development Consultants Ltd.
Website:
E-mail:
Phone:
www.hdc.ca
marketing@hdc.ca
(780) 463-3909
September, 2012
Describe Industrial Fire Detection
and Alarm Systems
Contents
Training Objectives
1
1
Introduction
1
2
System Requirements
2.1 Regulations
2.2 System Design
2.3 Fire Zones
2
2
5
9
xxx
x
3
4
System Components
3.1 Alarm-Initiating Devices
3.2 Central Control Unit
3.3 Fire-Indicating Devices
3.4 Power Supply
3.5 Emergency Communication Systems
3.6 Ancillary Devices
3.7 Fire Suppression Systems
3.8 Smoke Control Systems
10
13
16
17
21
21
21
22
25
Fire Detectors
4.1 Flame Detectors
4.2 Heat Detectors
4.3 Smoke Detectors
4.4 Carbon Monoxide Fire Detectors
4.5 Installing Fire Detectors
26
27
33
37
43
45
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Contents
(continued)
5
Central Control Units
5.1 Fire Control Panel
5.2 Modular Fire Controllers
5.3 System/Control Unit Security
5.4 System Bypass
45
45
48
50
52
6
One-Stage and Two-Stage Fire Alarm Systems
55
6.1 One-Stage Fire Alarm Systems
6.2 Two-Stage Fire Alarm Systems
6.3 Modified Two-Stage Fire Alarm Systems
55
56
57
7
System Monitoring
58
8
System Inspection, Testing, and Maintenance
8.1 Inspection
8.2 Testing
8.3 Maintenance and Repair
59
60
61
64
9
Limitations of Fire Detection and Alarm Systems
65
10
Self-Check
69
11
Self-Check Answer Key
76
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Describe Industrial Fire Detection
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Training
Objectives
1
Upon completion of this training kit, you will be able to:
 Describe the purpose and importance of industrial fire
detection and alarm systems
 Describe operator and maintenance personnel
responsibilities for the fire detection and alarm system
 Describe fire zones
 Describe fire detection and alarm system components
and ancillary devices
 Describe four types of fire detector
 For the four types of fire detector, describe:
 application
 limitations
 Describe two types of central control units
 Describe Stage 1 and Stage 2 fire alarms
 Describe precautions to take when one or more fire
zones is bypassed
 Describe fire detection alarm system inspection and
testing
 Describe limitations of fire detection and alarm systems
Introduction
Industrial fire detection and alarm systems are designed to:
 detect fires
 initiate alarms (locally and, for some facilities, off-site)
 activate fire isolation devices and/or fire suppression
systems (and, for some systems, activate or shut down
equipment)
This training kit describes components, operation, and testing
of industrial fire detection and alarm systems:
 fire alarm system regulations and design
 system components, including detailed descriptions of fire
detectors and central control units
 one- and two-stage alarms
 system monitoring, inspection, and testing
 limitations of fire detection and alarm systems
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Describe Industrial Fire Detection
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Although the kit briefly mentions fire suppression systems, a
description of these systems is beyond the scope of this
module.
The kit is for operators and maintenance personnel in industrial
facilities who may be required to:
 inspect components of fire detection and alarm systems
 occasionally assist certified fire alarm system technicians or
electricians with fire detection and alarm system testing
 respond to fire alarms
This kit is one of a series of three HDC training kits that
describe fixed detection systems commonly used in industry.
The other two kits are:
 Describe Fixed Combustible Gas Detection Systems
 Describe Fixed Toxic Gas Detection Systems
This kit provides instruction on fire detection and alarm system
components and their application. The kit does not endorse or
promote any specific model, manufacturer, or supplier.
2
System Requirements
2.1 Regulations
For public, commercial, and industrial buildings that are
normally occupied, every aspect of fire alarm system design,
installation, maintenance, and testing is closely regulated by
federal and state/provincial electrical and fire protection
standards and municipal building codes1.
Regulations that operators should be aware of include the
following:
 Fire alarm systems are not required in all buildings. Fire
alarm systems are generally required for buildings that are
normally occupied; however, an industrial facility may
1
Every jurisdiction publishes its own codes and standards about every
aspect of fire prevention. Many of these codes and standards form the basis
of building codes in the United States, Canada, and Europe.
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


include buildings equipped with fire alarm systems (e.g., an
office building, a service shop) and buildings not equipped
with fire alarm systems (e.g., unheated warehouses,
equipment installations, garages, and storage trailers or
sheds).
In fire alarm system-protected buildings, the system must
be installed throughout the entire building. All levels and all
areas of the building must be protected.
In fire alarm system-protected buildings, one centrally
controlled system must be provided for the entire building.
In facilities with several buildings, each fire alarm systemprotected building has a separate fire alarm system. The
facility may have a central monitoring station from which all
of the separate systems can be monitored.
Municipal fire inspectors, building inspectors, and fire insurance
company representatives routinely inspect industrial facilities to
ensure that the fire alarm system:
 meets applicable codes and standards
 is compatible with the facility’s current use (e.g., current
occupancy, type of operations and activities, products and
materials stored)
 is tested and maintained according to regulations
Standards
Fire detection and alarm systems and their components and
third party fire alarm monitoring stations must meet government
regulations (e.g., NFPA 72, EN 54) and cited standards.
Depending on the country, components must be certified by
organizations such as:
 Underwriters Laboratories of Canada (ULC)
 CSA (Canadian Standards Association)
 Underwriters Laboratories (UL)
 Factory Mutual (FM)
 European Committee for Technical Management
(CENELEC)
Personnel who install, adjust, repair, alter, or test fire
detection and alarm systems and components must be certified
(i.e., must successfully complete approved courses and/or
training).
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Unauthorized tampering with fire detection and alarm systems
places the lives of facility occupants in danger. Only certified
persons are permitted to install, service, and repair
components of fire detection and alarm systems.
Responsibilities
In an industrial facility, the facility’s owner is responsible for
providing a fire alarm system that is appropriate for the
operations and activities conducted, and meets the applicable
codes and standards.
The facility’s operator (e.g., owner, landlord) is responsible for
ensuring that:
 the fire alarm system is properly maintained and periodically
tested by certified fire alarm system specialists
 fire alarm procedures are developed and documented in a
Facility Fire Plan
 facility personnel are informed of the response procedures
described in the Facility Fire Plan
 fire drills are held periodically
All facility occupants are responsible for:
 learning the recommended fire alarm response procedures
(e.g., by reviewing the Facility Fire Plan)
 following the recommended procedure when a fire alarm
occurs
 helping those who need assistance to evacuate the building
or facility when a fire alarm occurs
Operators and maintenance personnel should be able to
identify:
 the buildings at their facility that have fire alarm systems
 the installations at their facility that have fire detection
systems
 the buildings and installations at their facility that do not
have fire detection and alarm systems
 the procedures to follow when a fire alarm occurs in their
work area, including:
– responsibilities/actions (e.g., shut down power supply)
– evacuation routes and procedures
– muster points
– fire department notification procedures
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2.2 System Design
Fire detection and alarm system design takes into account the
potential:
 locations of fire
 classes of fire
 stages of fire
 products of fire at each stage
Locations of Fire
Fires are most likely to occur in areas where any of the
following are present:
 flammable or combustible liquids or gases
 piles of combustible materials or wastes
 flammable mists, aerosols, dusts, and fibers
 smoking materials and open flames
 cooking equipment
 faulty or improperly-installed electrical or heating equipment
 poor housekeeping
This training kit differentiates between two types of systems to
detect fires and provide warning of the fire emergency:
 Fire alarm systems, which are installed in occupied
buildings. Fire alarm systems are designed to detect fires
and to warn occupants to evacuate to a safe location. Often
fire alarm systems also notify a monitoring station or the
Fire Department. This type of system is installed in
occupied buildings such as schools, hospitals, apartment
buildings, shopping malls, dormitories, and office buildings.
 Fire detection systems, which are installed in unoccupied
buildings, and to monitor processes and equipment. Fire
detection systems are designed to detect fires and to warn
any person in the vicinity to evacuate to a safe location.
Often fire detection systems are set up to notify a Control
Room or monitoring station. This type of system is typically
installed:
– in enclosed facilities and buildings that are not normally
occupied, (e.g., pump stations, utilities buildings,
unattended warehouses)
– on equipment (e.g., electrical transformers, conveyors,
utility tunnels)
– at outdoor facilities (e.g., fuelling stations, tank farms).
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Industrial facilities may have one or both types of systems,
depending on the types of buildings and installations present
and on the codes and standards that apply.
Classes of Fire
Fires are classified according to what fuels the fire. The table
on the next page lists the four classes of fire used in North
America, the type(s) of fuel each class involves, and typical
characteristics of each fire class.
Fire/fuel classification systems vary, depending on the country.
For example, the following system is used in the United
Kingdom and Europe: Class A––freely burning solid materials
(e.g., wood, paper); Class B––flammable liquids; Class C––
flammable gases; Class D––flammable metals; Class E––
energized electrical hazards; Class F––cooking oils and fats.
Classes of Fire (Canada/United States)
Class
A
B
C
D
Fuelled by
Description
combustible materials
(e.g., wood, paper,
plastics, straw)
flammable and
combustible liquid (e.g.,
petroleum, oil, lubricant—
POL–– solvents, grease)
live electrical equipment
(e.g., transformers,
electrical motors)


combustible metals
(e.g., magnesium, sodium,
titanium)










fire is slow to develop
more easily contained than the other
classes of fire
vapors burn quickly
produces intense heat
fire moves with the liquid, e.g., to low areas
difficult to contain
class is related to electrical hazard, not fuel
after electrical source is disconnected,
reverts to the class of the primary fuel
(e.g., Class A or Class B)
least common type
slow to ignite
once ignited, burns intensely
extremely difficult to extinguish
In an industrial facility, different classes of fire may occur in
different areas, depending on the products used, materials
stored, and activities taking place in the area. For example,
based on the above table, potential fires in a machine shop
may include:
 a Class A fire in the file storage room
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



a Class B fire in the solvent/cutting oil dispensing room
a Class C fire in the electrical room
a Class D fire in the room where welding rods are stored
a combined Class B, C, and D fire on the milling and
welding floor
Fire detection and alarm systems are specifically designed to
detect the types of fire that are likely to occur in different parts
of a facility.
Stages of Fire
There are four stages of fire (combustion):
 stage 1––incipient
 stage 2––smoldering
 stage 3––visible flames
 stage 4––intense heat
The length of time a fire remains in each stage depends on the
class of fire and the properties of the available fuel(s). For
example, in Class A fires stages 1 and 2 are of relatively long
duration; it may take several minutes, hours or days for the fire
to reach stages 2 and 3. For Class B fires, stages 1 and 2 are
extremely short; the fire enters stage 3 almost immediately and
rapidly progresses to stage 4.
The earlier the fire is detected:
 the earlier the fire alarm system can warn people to
evacuate to a safe location
 the higher the likelihood of extinguishing the fire before the
fire spreads or causes significant damage
Products of Fire
All types of fire produce four potentially harmful products:
 flames
 heat
 smoke
 toxic gases
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Different classes of fire produce different products at different
stages. For example:
 smoldering mattress––toxic gas is produced in the
incipient stage; during the smoldering stage, invisible and
then visible smoke are produced. As the fire progresses to
stages 3 and 4, flames and heat are produced.
 smoldering oily coveralls or rags— in stage 1, toxic gas
is produced; in stage 2, invisible smoke and then visible
smoke are produced. If the fire is not controlled, the fire
produces smoke and flames (stage 3) and heat (stage 4).
 burning gasoline––stages 1 and 2 are extremely short.
Flames and smoke are produced almost immediately
(stage 3), and then intense heat and toxic gas (stage 4).
Combustion (burning) of synthetic construction materials,
products such as adhesives, and furnishings can:
 produce extremely toxic gases (e.g., chlorine and cyanide) in
stages 1 and 2 that can cause poisoning, asphyxiation, and
death
 produce up to twice the amount of heat in stage 4 that is
generated by burning natural materials (e.g., wood, paper)
Fire detection and alarm systems are designed to detect
products generated at different stages of fires. For example,
most systems can detect:
 products of stages 1 and 2 (e.g., toxic gas, invisible smoke,
visible smoke)
 products of stages 3 and 4 (e.g., flames, heat), in case the
fire alarm system fails to detect products of earlier stages.
When the fire alarm system detects one or more products of
fire, the system activates fire alarms and may also activate
other systems to prevent the fire from spreading (e.g., door
closing devices, fire suppression systems).
Not all fire suppression systems are activated by the fire alarm
system (e.g., often sprinklers are activated directly by exposure
to heat, not by the fire alarm system).
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2.3 Fire Zones
In buildings, fire alarm systems are divided into different fire
zones. The fire zones are separated from one another, both
physically and electrically. Separation ensures that:
 malfunction/servicing activities in part of the system does
not shut down the entire fire alarm system.
 a fire cannot spread rapidly from one part of the building to
another (fire walls and fire doors help to isolate the fire).
 personnel and firefighters can quickly identify the location of
a fire. The greater the number of fire zones provided, the
more precisely the location of the fire can be identified.
Annunciator––
a panel with indicators
showing the status of
the fire alarm system in
each zone. The
indicators are typically
lights, LED, or text
displays.
Building code specifications include:
 the maximum size of each fire zone
 fire resistance ratings for vertical separations (e.g., fire
walls) between zones
 specific requirements for manual and automatic alarm
initiation devices (pull stations and fire detectors)
 specific requirements for fire detectors in elevator shafts,
stairwells, and ventilation ducts. When fire detectors are
installed in these areas, each area is considered a separate
fire zone.
 requirements for fire-indicating devices that notify building
occupants of a fire. Depending on the type of facility, the
devices may include:
– alarms, including audible and/or visible alarm devices
and signals)
– annunciators (a separate indicator light is displayed for
each fire zone)
Some fire alarm systems have different alarm signals for
different fire zones to help personnel identify the location
of a fire.
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3
System Components
Fire detection and alarm systems can be configured in different
ways, depending on the applicable codes. However, all fire
detection and alarm systems consist of four basic components:
 alarm-initiating devices, such as pull stations and fire
detectors
 a central control unit (fire control panel or modular fire
controller)
 fire-indicating devices, such as sirens, beacons, and
annunciators
 power supply
When an alarm-initiating device is triggered, a signal is
transmitted via the alarm circuit to the central control unit. The
central control unit activates the fire-indicating devices on the
circuit, sends alarm messages to remote annunciators, and,
depending on the system, may shut down and isolate
equipment. Figures 1, 2, and 3 show three different fire
detection and alarm system configurations that are commonly
used.
Figure 1—Fire Alarm System with Fire Control Panel
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Figure 1 shows the configuration typically used for occupied
buildings. Alarm-initiating devices are monitored and controlled
by a fire control panel (fire alarm system control panel, fire
control panel, fire cabinet). When a device initiates an alarm,
the fire control panel activates local and remote alarms,
ancillary devices, and suppression systems.
Figures 2 and 3 show the configurations typically used for
industrial processes and for industrial facilities such as fuelling
stations, pump stations, and tank farms.
Figure 2—Fire Alarm System with Modular Fire Controllers and PLC/DCS
In Figure 2, alarm-initiating devices communicate with, and are
monitored by a modular fire controller (rack-mounted controller,
fire control module). When the modular fire controller receives
an alarm signal, the fire controller relays the alarm signal to the
PLC or DCS (refer to the text box on page 14).
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When the PLC/DCS receives the alarm signal, the PLC/DCS
(i.e., not the modular fire controller):
 activates local and remote alarms
 depending on the operation or process, may:
– shut down equipment
– activate isolation devices and/or suppression systems
Figure 3—Fire Alarm System with Unitized Detectors and PLC/DCS
In Figure 3, unitized (stand-alone, intelligent, smart) fire
detectors can communicate directly with the station PLC or
DCS and a modular fire controller is not needed. When the
PLC/DCS receives an alarm signal, the PLC/DCS:
 activates local and remote alarms
 depending on the operation or process, may:
– shut down equipment
– activate isolation devices and/or suppression systems
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PLC: Programmable Logic Controller. A process automation
computer that receives input signals, makes decisions according to
a control program, and produces output signals.
DCS: Distributed Control System. A process automation computer
system where area computers throughout the facility receive area
input signals, make decisions according to an area control program,
and produce area output signals.
SCADA: Supervisory Control and Data Acquisition System. A data
transmission/computer system for centralized monitoring of
numerous remote facilities. Control systems (such as PLCs and
DCSs) at the remote facilities make process decisions, transmit data
and status signals to a centralized monitoring location, and receive
command signals from the centralized monitoring location.
In occupied buildings, depending on the applicable codes and
standards, fire alarm systems can be supplemented by:
 emergency communications systems
 ancillary devices
 fire suppression systems
 smoke control systems (required in high rise buildings and
residential institutions such as hospitals)
This section provides an overview of the principle components
of fire detection and alarm systems. Note that not all facilities
are equipped with all the components. During the walkthrough
that accompanies this training kit, you will have an opportunity
to identify the components at your facility.
3.1 Alarm-Initiating Devices
Alarm-initiating devices are critical components of fire detection
and alarm systems. For this reason, building codes and
industry regulations typically specify the required number, type,
and location of alarm-initiating devices. Alarm-initiating devices
must also meet specific standards and, once installed, be
regularly inspected, tested, and serviced to ensure they are
operating properly. Alarm-initiating devices fall into one of two
categories:
 manual alarm-initiating devices
 automatic alarm-initiating devices
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Manual Alarm-Initiating Devices
Fire alarm systems may provide manual alarm-initiating
devices, such as:
 manual pull stations
 break glass stations
 call (phone) boxes
Figure 4––Manual
Alarm-Initiating Devices
(Courtesy of The
Protectowire Company,
Inc.)
In occupied buildings, manual alarm-initiating devices are
installed in several locations on each level of the building,
including:
 normal traffic routes (e.g., in hallways, near exit doors,
outside stairwell entrances)
 hazardous work areas (e.g., process areas, laboratories,
paint booths, areas where flammable and combustible
materials are used, stored, or handled)
 areas where ignition sources, flammable or combustible
materials, or smoking materials are used (e.g., outside
mechanical rooms, in welding and grinding areas, in
cafeterias and smoking areas)
 areas where valuable items, equipment, or data are used or
stored (e.g., materials storage warehouses, garages, and
computer rooms)
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In occupied buildings, all manual devices are connected to the
fire control panel. Not all fire control panels are programmed to
respond the same way when they receive an alarm signal from
a manual device:
 Some fire control panels only activate building alarms. After
initiating the alarm at the manual station, personnel must
phone the fire department.
 Some control panels activate building alarms and,
additionally, may automatically notify either:
– the fire department
– a third party monitoring station. When a fire alarm is
received, the monitoring station personnel phone the fire
department.
Find out whether activating a manual station in your facility
automatically notifies the fire department or whether a separate
phone call is required.
Do not depend on a monitoring company to notify the fire
department. Phone lines can fail or personnel may be
responding to another call. When a fire alarm occurs, phone
the fire department immediately.
In addition to notifying the fire control panel, activation of a
manual device may automatically deactivate automatic door
locks. This feature is designed to enable evacuees to escape
without delay and to provide ready access to firefighters.
Automatic Alarm-Initiating Devices
Fire alarm systems include automatic alarm-initiating devices,
such as:
 fire detectors
 waterflow detectors
Fire detectors detect the products of fire (smoke, heat, flames,
or carbon monoxide). When a product of fire is detected, fire
detectors initiate an alarm via a signal to the fire control panel
or modular fire controller. As shown in Figure 3, unitized
detectors used in some industrial installations combine the
functions of a fire detector and a modular fire controller. These
unitized detectors do not need a fire controller, because they
can send signals directly to the installation’s PLC or DCS.
Fire detectors are described in detail in Section 4—Fire
Detectors.
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Waterflow detectors detect water flowing from sprinklers or
deluge systems and are described in Section 3.7—Fire
Suppression Systems.
3.2 Central Control Unit
As previously mentioned, two different types of control units are
used for fire detection and alarm systems:
 fire control panels, which are typically installed to monitor
buildings. Fire control panels carry out a wide range of
functions.
 modular fire controllers, which are typically installed to
monitor processes, equipment installations, and outdoor
facilities. Modular fire controllers carry out a much narrower
range of functions than fire control panels.
Features of both types of control units are described in detail in
Section 5—Central Control Units.
Fire Control Panel
The fire control panel is the brain of the building’s fire alarm
system. All circuits for the fire alarm system terminate at the fire
control panel, which is installed in a non-hazardous area.
When the fire control panel receives an alarm signal from an
alarm-initiating device (manual station, fire detector, or
waterflow detector), the panel activates:
 local fire alarms
 local annunciators
 ancillary activation devices
 fire suppression system activation devices
 alarms at remote monitoring facilities (e.g., one or more offsite monitoring stations, the fire department)
The fire control panel continually monitors the condition of all
alarm-initiating devices and circuits in the fire alarm system. If
an abnormal condition is detected, the control panel activates
appropriate alarms (e.g., FIRE, TROUBLE).
Older conventional fire control panels have separate displays
for each fire zone, but not for each alarm-initiating device within
a zone. For example, if any device in fire zone 3 initiates a
trouble alarm, the display for zone 3 indicates TROUBLE. A
newer type, the addressable fire control panel, has separate
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displays for each alarm-initiating device within each zone
(e.g., in zone 3, smoke detector 7 displays TROUBLE; all other
detectors display NORMAL).
Modular Fire Controller
As previously described, the modular fire controller carries out
fewer functions than the fire control panel. The modular
controller:
 is installed in a non-hazardous area that is relatively secure
 receives signals from manual alarm-initiating devices (fire
detectors and, if applicable, manual stations) and transmits
signals to the PLC/DCS.
The modular fire controller continually monitors the condition of
all alarm-initiating devices and circuits within its limited fire
detection system. If an abnormal condition is detected, the unit
transmits the appropriate alarm to the PLC/DCS (e.g., FIRE,
TROUBLE).
Both conventional and addressable modular fire controllers are
available:
 conventional controllers do not have separate displays for
each device (e.g., if any device initiates a fire or trouble
alarm, the controller displays FIRE or TROUBLE).
 addressable controllers have separate displays for each
device (e.g., smoke detector 4 displays TROUBLE; all other
detectors display NORMAL).
3.3 Fire-Indicating Devices
Fire detection and alarm systems provide two types of
fire-indicating devices:
 fire alarms
 fire annunciators
Fire Alarms
Fire alarms include:
 audible alarms (e.g., sirens, bells, horns, whistles, and voice
messages)
 visible alarms (strobe lights, beacons, text messages, alarm
icons or alarm pages on terminal screens)
September, 2012
Page 17 of 76
Describe Industrial Fire Detection
and Alarm Systems
Building codes have strict requirements for installing fire
alarms. For example, audible fire alarms must be:
 loud enough to be heard above background noise levels in
the building
 distinguishable from other signals or alarms that may occur
 installed in sufficient numbers and locations to be heard in
all parts of the building (e.g., in corridors, stairwells, storage
areas, operation and process areas, offices, lunchrooms,
washrooms, and locker rooms)
In high-noise areas, and in areas commonly occupied by
hearing-impaired persons, visible alarm displays must also be
provided. The displays must be:
 clearly visible to personnel working in any part of the room
 readily distinguishable from all other potential light displays
or effects
In addition to fire alarms, fire alarm systems provide other
types of alarms, including:
 trouble alarms, to notify personnel that one or more system
components is/are not functioning properly
 waterflow alarms, to notify personnel that water is flowing in
sprinkler system piping
Depending on the system, the alarms can be displayed as
audible and/or visible signals on detectors, fire control panels,
modular fire controllers, and on fire annunciators.
Fire Alarm Locations
Depending on the system, fire alarms can be activated in more
than one location, including:
 on the central control unit (fire control panel or modular fire
controller)
 on annunciators at one or more locations in the facility
 on monitoring screens at an off-site location, such as a:
– control room DCS or SCADA screen
– third party monitoring station
September, 2012
Page 18 of 76
Describe Industrial Fire Detection
and Alarm Systems
For their own facility, operators and maintenance personnel
should know:
 locations of on-site fire alarms
 whether fire alarms are monitored off-site (remotely)
Fire Annunciators
Fire annunciators, which are typically installed in buildings, are
also called repeater panels or annunciator panels. Figures 5a
and 5b show two different types of annunciators: a graphic
annunciator and a tabular annunciator.
Figure 5a––Graphic Fire
Annunciator
(Courtesy of Space Age
Electronics, Inc.)
Figure 5b––Tabular Fire
Annunciator
(Courtesy of Space Age
Electronics, Inc.)
September, 2012
Page 19 of 76
Describe Industrial Fire Detection
and Alarm Systems
Annunciators have different indicators (colored lights, LED
displays, or text displays) to indicate the current status of each
fire zone. Depending on the system, the indicator may be
activated either by the alarm-initiating device or by the fire
control panel. Typical indicators include:
 NORMAL—no fire, no mechanical or electrical problem
 FIRE––fire is detected; immediate action is required
 SUPERVISORY––a condition exists that is not normal and may
indicate a mechanical or electrical problem could occur in
the near future
 TROUBLE—a mechanical or electrical problem has occurred
or one or more components are disabled
 WATERFLOW ––water is flowing in the sprinkler system;
immediate action is required
Fire annunciators are not the same as fire control panels, even
though they look similar. Fire annunciators do not perform
control functions but can only display the status of fire zones
and alarm-initiating devices.
End of Sample
A full licensed copy of this kit includes:
• Training Module and Self-Check
• Knowledge Check and Answer Key
• Blank Answer Sheet
• Performance Checklist
The full version of this kit can be purchased at:
http://www.hdc.ab.ca/purchase_description.asp?ID=33
September, 2012
Page 20 of 76
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