Transcript
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Dr. Eng. Walid Abdelghaffar
wabdelghaffar@hotmail.com
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Dr. Walid Abdelghaffar2Detectors
Why alarm system?
A security and safety system is an investment for
your peace of mind. In general, a system is available
for any budget. Costs do vary and largely depend onwhich security features chosen and the protected
area.
Detect fire
Initiate alarms
Activate fire isolation devices and / or fire suppression
systems
Protect life and property
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Dr. Walid Abdelghaffar4Detectors
Detection System
Detection system selection must fulfill two
requirements:
1. It must be sensitive enough to detect combustion withinan acceptable and required time frame.
2. It must be reliable enough to not respond to non-fireactivation sources
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Dr. Walid Abdelghaffar5Detectors
A determination of the proper detection system
depends on:
A basic knowledge of the function of the different
detectors.
The hazard characteristics.
The stages of combustion.
Detection System
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Dr. Walid Abdelghaffar6Detectors
The Stages of Combustion
1.1. Incipient stageIncipient stage
2.2. Smoldering stageSmoldering stage
3.3. Flame stageFlame stage
4.4. Heat stageHeat stage
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Dr. Walid Abdelghaffar7Detectors
1. Incipient stage
where invisible products of combustion areproduced
At this stage, smoke is not visible, nor has the
heat of combustion developed.
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2. Smoldering stage
The smoldering stage
occurs when the combustionhas developed to the point where combustion
products are visible as smoke, but flame and heat
are not yet a factor.
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3.Flame stage
The flame stage is an intermediate stage whereconsiderable heat is not yet being produced by
the combustion , although this stage very quickly
moves into the next, the heat stage.In this stage there may be a clean flame, but little
or no smoke.
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4.Heat stage
The heat stage combines all theelements of combustion-invisible products as
well as visible smoke, flame, and heat.
Classification of fi e detecto s
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Dr. Walid Abdelghaffar11Detectors
Classification of fire detectors(EN 54 1976)
Detectors can be classified based on:
Fire phenomena
Response ModeResettability
Configuration
Detachability
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Fire phenomena:
Heat
Smoke
Gas
Flame
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Response Mode
Static
Differential
Rate of rise
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Resettability
Resettable
Self
Remotely Locally
Nonresettable
With exchangeable elements
Without exchangeable elements
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Dr. Walid Abdelghaffar15Detectors
Configuration
Point
Multi-point
Line
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Detachability
Detachable
No detachable
i ili
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Fire Detectors Families
FireFire
Turbulent FlowTurbulent Flow
Laminar FlowLaminar Flow
Ultra-VioletUltra-Violet
VisibleVisible
Infra-RedInfra-Red
VisibleVisible
InvisibleInvisible
GaseousGaseous
AerosolAerosol
ConvectionConvection
RadiationRadiation
SuspensionSuspension
ResidualResidual
Thermal EnergyThermal Energy
Conservation
Of Matter
Conservation
Of EnergyFlame
Detector
Heat
Detector
Smoke
Detector
1 S k
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Dr. Walid Abdelghaffar18Detectors
1.Smoke Detectors
1. Photoelectric Smoke Detector
2. Ionization Smoke Detectors
1.Photoelectric Smoke Detectoruses the light-reflection principle to detect smoke.
A) spot type detector
B) beam/line type detector
C) duct type detector
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Dr. Walid Abdelghaffar19Detectors
. o o-e ec r c smo e e ec or
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. o o e ec r c smo e e ec orA) spot type detector
Ph t l t i S k D t t
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Smoke free chamber light
beam travels straight
through
Smoke particles in
chamber deflect some
light rays
Photoelectric Smoke Detector
Ph t l t i S k D t t
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Dr. Walid Abdelghaffar22Detectors
The refractory photocell uses a light beam that passesthrough a small chamber at a point away from the light
source. Normally, the light does not strike the photocell,
and no current is produced. When a current does notflow, switch in the current remains open.
When smoke enters the chamber, it causes the lightbeam to be refracted (scattered) in random directions. A
portion of the scattered light strikes the photocell causing
current to flow. This current closes the switch andactivates the alarm signal
Photoelectric Smoke Detector
Photoelectric Smoke Detector
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Dr. Walid Abdelghaffar23Detectors
A photoelectric smoke detector is activated by visible smokeparticles entering the detector.
The photoelectric detector responds to the thicker, heavier,visible smoke that develops when slow-developing andsmoldering combustion is presented.
A slow-burning or smolder fire is typical of combustion ofmaterials found in the office, home photoelectric, hotels, andhospitals.
The engineer may, in order to provide reliable combustiondetection, recommend the installation of both ionization andphotoelectric detectors if the type of fire potential cannot be
readily determined
Photoelectric Smoke Detector
Photoelectric Smoke Detector
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Dr. Walid Abdelghaffar24Detectors
In an effort to obtain a sensitive, early warningdetection system where ionization detectors appear tobe the best selection, it is imperative that the general
environment be considered because these detectorswill react to many non-fire invisible particles, includingexhaust fumes, welding operations, kitchen odors, andpilot lights.
Maintenance is a prime consideration with detectionsystem.
Dust and contamination can affect the sensitivity of anydetector, either by making it more sensitive to non-fire
detection sources, or by reducing the sensitivity
Photoelectric Smoke Detector
Signal Conditioning Circuit for
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g gPhotoelectric Smoke Detector
B) beam/line type detector
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B) beam/line type detector
ReceiverLight Source
Light Beam
Clean Air
ReceiverLight Source
Light Beam
Smoke Particle
Linear Beam Smoke Detector
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Dr. Walid Abdelghaffar27Detectors
Linear Beam Smoke Detector
The linear beam smoke detector basically operates on the sameprinciple as the photoelectric smoke detector with a light sourcedirected on a photo-sensitive receiver.
The difference is that the linear beam smoke detector consists of
two separate units. The light source is one piece of equipment,and the light beam receiver is a separate piece of equipment.
The linear beam smoke detector light source, or transmitter,emits an invisible infrared beam over open area distances of 35'
to 300' on to the light receiver.
When no smoke interferes with this beam, the receiver acceptsthe beam at a specified voltage level, but when smoke interferes
with the beam, the infrared light reaching the receiver islessened, and when the beam intensity drops below thepredetermined sensitivity level of the receiver, it initiates a signalfrom the detector
Linear Beam Smoke Detector
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Dr. Walid Abdelghaffar28Detectors
This type of smoke detector has many applications in
areas where spot-type smoke detector could not be
installed to operate efficiently,
Such as:
Airport terminals.
With very high ceilings.
Aircraft hangars.
Churches, and large open facilities.
Linear Beam Smoke Detector
C) duct type detector
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Dr. Walid Abdelghaffar29Detectors
C) duct type detector
Duct detector
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Dr. Walid Abdelghaffar30Detectors
Duct detector
Duct detectors are ionization photoelectric. They are usually installed on a return air duct close to the fan unit.
Duct detectors are installed on the exterior of the duct with longtubes extending into the duct .these tubes have holes that pick upproducts of combustion. In the air stream returning from the ventsin the facility, transmitting them into the detector unit on theoutside the Duct
When the detector is activated, one of the signals it actuates is anautomatic shut-down of the heating and air-conditioning fans toprevent the products of combustion from being sent back throughthe heating and air-conditioning system throughout the building.
Duct detectors provide an excellent function but always keep inmind that they should not substitute for a detection systemthroughout the facility
2. Ionization smoke detector
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2. Ionization smoke detector
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Ionization detector
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Ionization detector
In evaluating the hazard, the level of required detection
sensitivity, the environment in which the detector will function,and the type of combustion anticipated, it may be determinedthat the combustion should be detected in the incipient stagebefore there is appreciable heat and smoke in order to
prevent heat and smoke damage to delicate electronicequipment.
In such cases, ionization detectors should be seriously
considered because they react when invisible products ofcombustion are given off by the combustion before there isvisible smoke has developed.
The analysis of the combustibles present and the type of fire
that these combustibles will produce should be the firstconcern when making a detection selection.
Fire that develop rapidly into flaming stage without the
accumulation of heavy, visible smoke particles are detectedmost effectively by ionization detectors.
Photoelectric Verses IonizationS k D t t
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Dr. Walid Abdelghaffar34Detectors
Smoke Detectors
Photoelectric
-Respond more quickly to smoldering fires
Ionization-Respond more quickly to flaming fires with smaller combustion
particles
-Less expensive-Less power requirements
Limitation is the radio active materialused in it.
2.Heat Detectors
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Dr. Walid Abdelghaffar35Detectors
2.Heat Detectors
1. Fixed temperature heat detectorsResponds to changes in ambient temperature
a) Spot type
b) Bimetal
2. Rate-of-rise heat detectors
Respond to the sudden change or Rateof rise inambient temperature from a normal baselinecondition
a) Rate compensated detectors
b) Rate of rise detectors
3. Combination detectors
Thermal detection systems
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Dr. Walid Abdelghaffar36Detectors
Thermal detection systems
The operation of thermal detectors is the leastsophisticated of all the detectors
Thermal detectors are designed to actuate at apredetermined fixed temperature.
They should be used when the protected hazard areahas the potential to produce considerable combustionheat, or at least sufficient combustion heat to activate
the detector before considerable damage is donepassing through the early stages of the combustion.
A sprinkler head is actually a thermal detector, when
combustion heat reaches the temperature setting of thefusible element of the sprinkler head, the fusible elementmelts, or softens sufficiently to release the head linkage,thereby releasing the discharge. The water movement in
the piping actuates a device that transmits an alarm
Thermal detection systems(cont,)
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Dr. Walid Abdelghaffar37Detectors
y ( ,)
The sprinkler head is a good example of a non-restorabledetector.
Once the head is activated, it must be replaced.
A thermal element melts at a predetermined temperature,
releasing a mechanical arrangement such as a spring or aplunger which makes or breaks an electric circuit, activatingthe alarm system.
Other thermal detectors are available that activate at a
predetermined fixed temperature, but are self- restoring.After the detector has been activated and the combustionheat removed, the detector returns to room temperature andautomatically resets it self
When designing a detection system that activates asuppression system, and the detectors are self-restoring,always determine what may be required to maintain thesuppression system in an operating condition should thedetector reset
1.Fixed temperature heata) Spot type
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Dr. Walid Abdelghaffar38Detectors
a) Spot type
Detect heat by one or more of 3 primaryprinciples of physics:
1. Expansion of heated material
2. Melting of heated material
3. Changes in resistance of heated material
Spot type
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p yp
Has a detecting element or elements that respond to
temperature conditions at a single point or in a small area.
Designed for one-time operation, and the whole device or the
element needs to be replaced.
Usually 57C to 62C or 85C to 92C
Fixed-temperature devices
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Dr. Walid Abdelghaffar40Detectors
Fixed temperature devices
That melt employ soft metal alloys or thermoplasticresins to hold together a two-piece link or latchingmechanism. A frequently used metal alloy is solder.
When the solder melts, the link separates or the latch isreleased, causing an alarm signal to sound.
Another type of fixed-temperature device actuatesthrough the expansion of heated solvents. In this type ofdevice, small glass bulbs contain solvents; the bulbs aremanufactured to break at predetermined pressures.
When the solvent is heated, it vaporizes. The resultingvapor pressure breaks the glass bulb, which has beenholding two electrical contacts apart. the contacts close,
causing an alarm signal to be send.
1.Fixed temperature heata) Bimetal type
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Dr. Walid Abdelghaffar41Detectors
a) Bimetal type
Contact
Metal A
Metal B
WiringTerminal
Uses 2 metals with different thermal expansion
characteristics, when heated, 1 metal expands faster than
the othercausing the strip to bend or arch, Deflection of
strip makes or breaks alarm circuit, initiating an alarm
Automatically when cooled
2.R-O-R heat Detector
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Dr. Walid Abdelghaffar42Detectors
a) Rate-compensateddetectors b) Rate-of-rise detectors
-When temp rate of r ise increase the pressure change rate
increase, at low rates the high pressure air allowed to escape
through an air breather and at high rates it affects a bellowdiaphragm and causes the alarm
Rate of Rise Detector
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Dr. Walid Abdelghaffar43Detectors
The rate of rise detector responds to a rate oftemperature rise of 15 C per minute regardless of the
room's ambient temperature. This feature gives the
rate of rise detector an advantage over thermal
detectors because it is not affected by thermal lag.
The rate of rise detector is activated by the very rate
of temperature rise that is lost with a thermal detector.
If the temperature rises at the rate of 15 C per minute,
the rate of rise detector will activate.
Rate of Rise Detector
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Dr. Walid Abdelghaffar44Detectors
There are certain disadvantages of the rate of risedetector:
1. Slow-burning or smoldering combustion may produceconsiderable heat, and the ceiling where the detector is
located may rise to a very high temperature, but unless
the rate of heat rise is rapid enough to produce a 15 Cper minute increase, the detector will not activate.
2. It is for this reason that combination fixed temperatureand rate of rise detectors are used to overcome the rate
of temperature rise disadvantage
Rate-of-rise detectors
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Dr. Walid Abdelghaffar45Detectors
Respond to quick changes in temperature rather thanactivating at a fixed temperature.
Most rate-of-rise detectors have a small chamber filled
with air.A small vent from the chamber allows for slow changes
in temperatures.
If rapid heating occurs, however, the air inside thechamber expands. The small vent cannot relieve thepressure, which forces a diaphragm out.
The movement of the diaphragm either opens or closes
a set of electrical contacts than initiate an alarm signal
Rate compensation detector
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Dr. Walid Abdelghaffar46Detectors
The rate compensation detector, sometimes referred toas a rate anticipation detector, consists of two metallicstruts mounted inside of a steel elongated shell.
The stainless steel shell has a coefficient of expansion
greater than the two metallic struts mounted within it.When the shell is exposed to heat, it expands, and since
the ends of the two struts are attached to either and ofthe shell, the expanding shell pulls the struts and
stretches them until they make contact at the center ofthe struts.
Rate compensation detectors have a predeterminedfixed temperature set point, and when the two struts
make contact and activate the detector, it has reachedthis temperature set point.
Rate compensation detector
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Unlike the rate of rise detector that requires a minimum15 C per minute rate of temperature rise to operate, asmoldering fire producing a slow rise in temperature
heat both the outer and the struts equally until the setpoint of the detector is reached
When the combustion heat is rapid, the ratecompensation shell expands rapidly until the struts arestretched to the point of contact, thus eliminating thethermal lag that may prevent a fixed temperature
detector from operating when the surrounding air hasreached the set point of the detector.
Heat actuating Device (H.A.D)
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Dr. Walid Abdelghaffar48Detectors
The heat actuating devise, commonly referred to as theH.A.D is a rate of the rise detectorthat has been on themarket and in service for many years
Basically, the H.A.D is a hollow cylinder connected to the
system operating devices through small copper tubing. When there is an increase in combustion temperature,
the air in the H.A.D expands and the pressure created istransmitted through the copper tubing to activate a
diaphragm, or equivalent device that reacts to increasepressure.
This detection system is pneumatic, and as a result, hasbeen used frequently in areas where flammable vapors
may be present and an electric spark from electricdetector activation could cause an explosion.
Heat actuating Device (H.A.D)
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Dr. Walid Abdelghaffar49Detectors
The H.A.D pneumatic system copper tubing is connected to adevice called a mercury check
The mercury check acts as the environmental temperaturechange vent for a group of H.A.D's that connected to themercury check.
The mercury check prevents an increase in pressure in oneH.A.D in the group from being dissipated by pressurizing theother H.A.D's in the group
The mercury check is a retard device to prevent false alarms.
Thermostatic release
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Dr. Walid Abdelghaffar50Detectors
There is detector on the market that operates on the rate of rise
principle when the detector is subjected to a temperature rate increaseof 15 C or more per minute.
This detector can also be equipped with a sprinkler head to serve as afixed temperature detector.
The detector can function as a pneumatic or hydraulic system.
The thermostatic release detector operates on the principle of two
metals expanding at different rates when subjected to temperaturechange. The tube expansion exerts a pulling force on the rod, which inturn mechanic operates a valve that releases pressure on diaphragm,which then raises a clapper and vents the system.
The valve is actually a Schrader valve, the same valve found on thetires of a car or bicycle. When the rod is pulled by the expanding tube,it depresses the stem of the diaphragm then opens the vent, releasingair when the system is pneumatic, and water when the system ishydraulic
om na on xe empera ure nrate of the rise detector
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Dr. Walid Abdelghaffar51Detectors
The combination fixed temperature and rate of the risedetector are used to overcome the rate of temperaturerise disadvantage.
The combination fixed temperature and rate of the risedetectors are activated when the rate of the temperaturerise is 15 c or more per minute. it also has a fusibleelement with a predetermined operating temperature.
The combination electrical spot detector is hollow shellcontaining a diaphragm . When the shell is subjected to
combustion heat that is increasing in temperature at arate of 15 C per minute or greater, the air trapped in thedetector shell expands, thereby forcing the diaphragm upto make an electrical contact that closes a current and
activates the system.
Combination rate-of-rise/fixed temperature detectors
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Dr. Walid Abdelghaffar52Detectors
p
Feature the quicker reaction rate of the rate-of-rise
detector coupled with the higher dependability of thefixed- temperature unit
Pilot heat system
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Dr. Walid Abdelghaffar53Detectors
The pilot heat detection system is a thermal detection systemfrequently used to activate suppression system.
The pilot heat system uses regular sprinkler heads as the thermaldetectors
These heats are installed on pipe which is filled with compressedair.
When a heat fuses, the compressed air is released, and the release of
compressed air pressure activates the suppression system valve
The pilot head detection system is very reliable in that it is not subjectto false trips from non-fire sources, which can cause havoc with otherdetector that, operate on a principle other that heat.
Pilot heat detection systems are frequently used to activate coolingtower and outdoor transformer deluge suppression system.
3.flame Detectors
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Dr. Walid Abdelghaffar54Detectors
A device which detects the infra-red, ultraviolet, or visibleradiation produced by a fire.
Ultraviolet
infra-red
UV/IR Visible sensors
detectors work according to wavelengths to detect fires and
explosions within mil liseconds
mRadiant Energy
0.1-0.35Ultraviolet
0.36-0.75Visible
0.76-220Infrared
Flame Detectors
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Ultraviolet Infrared
Most sensitive to detect fires, but also easily activated by non-fire
conditions (e.g.. welding, sunlight etc.)
Must be positioned with an unobstructed view of the protected area and
will not activate if line of site is blocked.
IR detectors are designed to require the flickering motion of flame ,UV
detectors insensitive to sunlight so they can be used in areas not
suitable for IR detectors
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Carbon Monoxide detectors
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Advantages of Carbon Monoxidedetectors over any other detector:
improved the speed of detection from slow
smoldering fires.
reduced the possibility of false alarms thansmoke detectors.
Four types of sensorsIn
carbon Monoxidedetector1. Opto-Chemical
2. Biomimetic
3. Electrochemical
4. Semiconductor
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Detectors Summary
Type of Detector Advantage Disadvantage
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Type of Detector Advantage Disadvantage
Ionization Smoke Detector
Effective at sensing fast flaming
fire, low cost and simple to
manufacture
Sometime too expensivecausing nuisance alarms and it
contains radioactive element.
Also, not effect ive at sensing
slow smouldering fire.
Photoelectr ic Smoke Detector Effective at sensing slowsmoldering fire High cost and not effective atsensing fast flaming fire
Air Sampling Smoke DetectorVery sensitive and have
multiple methods of operation.
Complicate to design and have
high cost. Vulnerable to
nuisance alarms.
Fixed Temperature Heat
Detector
Very sensitive to manufacture
and the production cost is not
high.
Easier to give false alarmscomparing with other heat
detectors and it needs to be
well placed for it to operate
effectively.
Rate Compensating Heat
Detector
More flexible and reliable than
fixed temperature detectors.
For effective operation it needsto be well placed. Additionally,
more complicated to
manufacture hence, possibly of
high cost.
Rate of Rise Heat DetectorRelatively simple tomanufacture and are more
sensitive.
Also need to be placed
efficiently. Vulnerable to
sudden environmental changes
thus causing nuisance alarms.
System design
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Takes into account:1. Location of fire
2. Classes of fire
3. Stages of fire (incipient, smoldering, visible
flames and intense heat)
4. Products of fire at each stage (Flames, Heat
,Smoke, Toxic gases )
Alarm & detection
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Fire alarm systems:installed in occupied building such as schools, hospitals,
designed to detect fires and to warn occupants forevacuation and notify a monitoring station or a firedepartment.
Fire detection system:
installed in unoccupied building to monitor processesand equipment, Is set up to notify a control room ormonitoring station, is typically installed:
The system may be:
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1. An alarm system2. A suppression system
3. An equipment shut-down system
4. An equipment start-up system5. A combination of any of these systems
By closing the electrical circuit, the detector signals thecontrol panel which transmits a signal to the varioussystems.
System components
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Primary (AC)
Control panel
Secondary (DC) output
input
System components: (CPU)/controlpanel
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Main function Receives signals from initiation devices (contacts, motion
detectors, smoke detectors etc.) and activates appropriate
notification devices (dialer, horns, strobes etc.)
Electrically monitors system wiring and primary power
Supplementary functions Elevator capture
Equipment shutdown
Air handling shutdown
Event printing
Door holding devices
Display monitor interface
(CPU)/control panel
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CONVENTIONAL SYSTEMS
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Conventional system
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-A building is sectioned into zones.
Conventional detectors have two states, normal and alarm.
-Each zone is wired back to the fire indicator panel (FIP)
separately
Fire Alarm Control Panel
I Conventional Panels
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Have a small number ofcircuits, each circuit covering
a zone within the building. The main drawback with
conventional panels is thatone cannot tell which device
has been activated within acircuit.
They are no longer used
frequently in large buildings,but are still used on smallersites such as small schools orapartments.
I. Conventional Panels
I. Conventional Panels
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Fire Alarm Control Panel
I. Addressable Panels
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Much more advanced
Panels usually have a numberof signaling line circuits (slcs)
within the range of one to thirtycircuits.
Each slc can have a number ofdevices connected to it. Each
device has its own address,and so the panel knows thestate of each individual deviceconnected to it.
A loop may have up to 200device
I. Addressable Panels
II. Addressable Panels
Common addressable input (initiating) devices include:
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Common addressable input (initiating) devices include:
Smoke detectors
Manual call points
Responders
Fire sprinkler system inputs Switches
Flow control
Pressure Isolate
Standard switches
II. Addressable Panels
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Addressable output devices are known as relays andinclude
(Warning System/Bell) Relays
Door Holder RelaysAuxiliary (Control Function) Relays
Relays are used to control a variety of functions such as
Switching fans on or off
Closing/opening doors
Activating Fire Suppression System
Activating notification appliances
Shutting down industrial equipment
II. Addressable Panels
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Addressable system
Connected in constant two-way communication with the
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y
control panel Continuously monitor the protected area for changes in temp.
or air clarity.
Any abnormal change communicated to the fire panel which- after analyzing the signals - then makes the decision totrigger the alarm and shows which detector is indicating a firein a specific part of the building
Control Module
Is a device connected to the addressable control panel
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Is a device connected to the addressable control panelbut it allowing an extension to another conventionalcircuit.
Is also connected with the fire control power supply
(FCPS)NOTE THAT: FCPS gives up to 4 amp current and uses about 24 volt
,and can be connected to more that one control modulewhich will not give out more than 1 amp to notificationdevices connected to it.
An isolator is put after every 20 digital components(detectors, control modules, call points,..) to avoid failure incase of shortcuts.
Control modules activate a conventional sound circuitaccording to the signal received from the control panelwhich can be programmed to activate all the sound circuitsin all floors.
System components: Mon tor ngsystem
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MonitoringIf an alarm being tr iggered the 24-hour monitoring station
immediately summons help from the police or fire
departments.
Arming StationsKey operated arming stations use a high security key to arm
and disarm the system. A more common type of arming
station is the digital key pad.
Types of keypads:
L-E-D
L-C-D
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Manually activated devices
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Fire alarm pull station Manual call point " break glass"
Automatically activated devices:Fire detectors
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Line-Type detectors:A device in which detection is
continuous along a path.Spot-Type detector:A device whose detecting element
is concerned at a particular location.
System components:
System output/ Fire-indicating devices
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A) Audible devices-Such as horns, bells, sounders, sirens, chimes and speakers. They
are designed to produce a very loud, hard to ignore sound whenactivated.
-They are available in many shapes and sizes.
System output/ Fire-indicating devices
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An average ambient sound level greater than 105 dB shallrequire the use of a visible signal appliance(s)
The total sound pressure level produced by combining the
ambient sound pressure level with all audible signaling
appliances operating shall not exceed 120 dB anywhere in the
occupied area.
Audible devices
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Strobes/flasher light can be used to visually indicate an alarmcondition. Various color lens can be used to differentiateseparate events.
Strobe lights usually flash to save power and attract moreattention. Strobe lights can help authorities locate the site ofan alarm
Outputs
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Bells
Siren Flasher
Annuciator
System Control Wiring andconnections
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Signaling Line Circuits (SLCs Loops)
Control panel wiring
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Control panel wiring
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Control components wiring
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Control Module
SLC Loop
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24 VDC
Power FCM addressable control module control panels circuit to
control appliances (horns, strobes, speakers, act) by meansof a digital signal from FCP or to monitor telephone circuit.Addressability allows the FCM to be activated, either manuallyor through panel programming, on a selected (zone or area ofcoverage) basis.
Control Module
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Control Module
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Monitor module
It is a transducer for monitoring the status of analogue
devices like sounders and manual call points and transmit
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devices like sounders and manual call points and transmitdigital signal to the control panel.
Monitor module
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Relay module and contacts
Provides the system with dry-contact output for activating a
verity of auxiliary with device such s fans dampers control
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Normally Closed
Norma lly OpenCommon Normally Closed
Norma lly Open
Common
verity of auxiliary with device, such s fans, dampers, control
equipment, ect.
Relay module and contacts
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Fault Isolator Module
Isolator Module should be spaced between groups ofsensor in loop to protect the rest of the loop Use to
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Isolator Module should be spaced between groups ofsensor in loop to protect the rest of the loop. Use to
isolate short circuit problems within a section of a loop so
that other sections can continue to operate normally.
The Isolator Module supports a maximumb f d i i b t i l t t
Relay module and contacts
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The Isolator Module supports a maximumnumber of devices in between isolators, expect
when using relay bases.
Detectors wiring
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Power Sources
NFPA Code number 74 requires that AC powered units
meet the following conditions:
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meet the following conditions:
Power supply must be sufficient to operate the alarm
signals of 85 decibels for at least 4 consecutive minutes.
A visible Power On indicator must be provided.
All electrical systems designed to be installed by
someone other than a qualified electrician must be
powered from a source not in excess of 30 volts. These systems should meet the requirements for power-
limited fire-protective signaling circuits as defined in
Article 760 of the National Electric Code number 70. The power source for the unit must not be subject to loss
of power by a wall switch.
Power Sources
A restraining means should be used at the plug-in
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A restraining means should be used at the plug inof any cord-connected installation.
Single-station and multiple-station smoke
detectors, powered from 120 VAC sources, should
not be installed on circuits protected by a groundfault circuit interrupter.
Neither loss nor restoration of the primary powershould cause an alarm signal.
Battery-Operated Units
NFPA Code number 74 requires that
battery-operated units meet thef ll i i t
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y pfollowing requirements The alarm must be capable of
producing an alarm signal of 85
decibels for 4 consecutive minutes. The batteries must meet all power
requirements for at least one year,including routine testing.
A distinctive, audible trouble signalmust be given at least once per minutefor seven consecutive days before thebatteries are incapable of operating
(from aging, terminal corrosion, etc.). The unit must also be capable of
producing the alarm signal for 4consecutive minutes during the sevendays of trouble signal.
Photoelectric smoke
detector equipped with
strobe light for the hearing
impaired
System design requirements
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System design
requirement
Power supply
Smoke and heat
detector
installation
maintenance
Installation of detectors
Consideration should be followed in installation of
detectors: Wh i t lli th k l th t
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When installing the smoke alarm ensure that:
on the ceiling, ensure it is a minimum of 10cm fromany wall.
If wall mounting it is a minimum of 10cm below theceiling, but no lower than 30.5cm below the ceiling.
if it is more than 9 meters long install smoke detectors
at both ends of the room. Ideal location is on the ceiling in the centre of the
room.
Installation of detectors
In stairways install smoke alarms anywhere in the path of
smoke moving up the stairs.
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For sloped type ceilings, install the smoke alarm 10cm
below the peak.
Installation of detectors
Locations to Avoid:
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avoid dead air pockets.
Installation of detectors
Do not install a smoke alarm within 1 meterfrom kitchen,
bathroom, forced air ducts used for heating or cooling,til ti f i diti it
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ventilation fans, air conditioner units.
To avoid nuisance alarms: Install smoke alarms at least 30 cm away from
fluorescent lighting.
Avoid Dust particles, insects and dirties.
Do not install in areas where the temperature is
colder than 4.4C or hotter than 37.8C (100F)
Smoke Fire Detectors location andspacing
Locationconditions that shall be included according to
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conditions that shall be included according to
NFPA:
Ceiling shape Ceiling height
Configuration of contents
Burning characteristics Ambient environment
Smoke Fire Detectors
Detectors according to installation:
Spot Type Smoke Detectors
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Beam Type Smoke Detectors
Smooth Ceiling Spacing Spot type detectors. On smooth ceilings, spacing of
9.1 m shall be permitted to be used as a guide.
Smoke Fire Detectors
Projected beam type detectors On smooth ceilings, a spacing of not more than 18.3 m between
j t d b
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projected beams
Smoke Fire Detectors
High Air-Movement Areas
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Heat-Sensing Fire Detectors locationand spacing
Location
Spot-type heat-sensing
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Spot type heat sensing
Line-type heat detectors
on the ceiling or on the sidewalls not more than(500 mm) from the ceiling.
Heat-Sensing Fire Detectors
Smooth Ceiling Spacing
The distance between detectors shall not exceed their
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listed spacing
detector shall be installed within a distance equal to
0.7 times the listed spacing (0.7S).
Heat-Sensing Fire Detectors
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Heat-Sensing Fire Detectors
High Ceilings
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Alarm detectors Maintenance
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Cleaning Alarm detectors
Alarm detectors testing
Replacing Outdated Alarms
Maintenance of Power Supply
Visible System Characteristics andlocation
Visible Characteristics
Light Pulse Characteristics
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The flash rate shall not exceed two flashes
per second (2 Hz) nor be less than one flashevery second (1 Hz).
light source color shall be clear or nominal
white and shall not exceed 1000 cd.
Visible System location
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Visible System location
If ceiling heights exceed 30 ft (9.14 m), visiblenotification appliances shall be suspended.
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Room spacing for wall-mounted appliances shall be
based on locating the visible notification appliance at the
halfway distance of the longest wall.
Spacing in Rooms
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Spacing in Corridors
The table shall apply to corridors not exceeding 20 ft (6.1
m) in width.
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Audible System Characteristicsand location
Audible CharacteristicsMechanical Equipment Rooms
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the average ambient sound level used for design
guidance shall be at least 85 dBA
Public Mode Audible Requirements
sound level of not less than 75 dBA at 10 ft (3 m) ormore than 120 dBA at the minimum hearing distancefrom the audible appliance
Audible System location
Location of Audible Notification Appliances
If ceiling heights allow, wall-mounted appliances shall
have above the finished floors not less than 90 in (2 30
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have above the finished floors not less than 90 in. (2.30
m) and below the finished ceilings not less than 6 in.
(152 mm).
Heat Detectors Installation
Heat Alarms are ideal for kitchens, garages, boiler rooms,attics and other areas where there are normally high levels
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of fumes, smoke or dust which preclude the use of Smoke
Alarms due to the risk of false alarms.
On sloped, peaked or gabled ceilings, install Heat Alarm
30cm from highest point.
If only wall placement is possible, install no further than
30cm from ceiling.
Do not install Heat Alarms directly over the cooker, stove
or oven or In areas with high humidity, like bathrooms or
shower rooms, or areas near dishwashers or washingmachines Install heat alarms at least 3m away from these
areas if possible.
According to NFPA Code number 72
Location: Spot-type heat-sensing fire detectors shall belocated on the ceiling not less than 4 in. (100 mm) from
Heat Detectors Installation
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the sidewall or on the sidewalls between 4 in. and 12 in.
(100 mm and 300 mm) from the ceiling.
Exception: In the case of solid joist construction,
detectors shall be mounted at the bottom of the joists. In the case of beam construction where beams are
less than 12 in. (300 mm) in depth and less than 8 ft
(2.4 m) on center, detectors shall be permitted to beinstalled on the bottom of beams.
Line-type heat detectors shall be located on the ceiling
or on the sidewalls not more than 20 in. (500 mm) fromthe ceiling.
Heat Detectors Installation
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Exception No. 1: In the case of solid joist
construction, detectors shall be mounted at thebottom of the joists.
Exception No. 2: In the case of beam constructionwhere beams are less than 12 in. (300 mm) in depth
and less than 8 ft (2.4 m) on center, detectors shall be
permitted to be installed on the bottom of beams.
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Dr. Eng. Walid Abdelghaffar
wabdelghaffar@hotmail.com
mailto:wabdelghaffar@hotmail.commailto:wabdelghaffar@hotmail.com
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