11 Fire Detection And Alarm Systems Flashcards
This is essentially the brain of the alarm system
Fire alarm control panel FACP
Primary electrical power supply for alarm system
Buildings main power supply
A secondary power supply must be able to make the fire detection system fully operational within what time of the main power failure
30 seconds
Storage battery for alarm system cannot be
Dry cell battery
Secondary power supply must be one of the following
Storage battery and charger
Generator and 4 hr capacity battery
Multiple generators, one with auto start
Trouble signal must have a different power source than the main power true false
True
System component that generates and audible visual or motion signal to alert humans to activation of alarm initiating device
Signaling device
Most common signaling decides
Audible
Sometimes called detectors, constantly monitor the condition of the atmosphere
Automatic alarm initiating devices
Four types of automatic detectors or initiating devices
Heat, smoke, fire gas, and flame
One of slowest to respond, but relatively inexpensive, and least prone to false activations
Fixed temp heat detectors
Heat detectors operate based one one of these principles
Heat causes expansion
It causes melting
It has detectable thermo electric properties
Type of heat detector using two different metals with different expansion rates
Bi metallic hear detector
True false. Most bi metallic heat detectors are NOT self resetting
False they are
Material that is not a good conductor or insulator and may be used as both
Semiconductor
Heat detector that can be used to detect conditions over a wide area
Continuous line heat detector
Conductive metal inner core cable sheathed in stainless steel tubing. self restoring. Heat detector
Tubing type continuous line
Two wires that are each insulated and bundled within an outer covering. Insulation melts and two wires touch. To restore, fused portion must be removed and replaced.
Wire type continuous line heat detector.
Two most significant factors in preventing large fire losses
Early detection and proper signaling
Detector designed to operate on the principle that fire is rapidly increase the temperature in a given area
Rate of rise heat detector
Compared to fix temperature heat detectors rate of rise respond how
At substantially lower temperatures
Typically rate of rise heat detectors are designed to send a signal when the rise in temperature exceeds what temperature per minute
12-15°F for minute
True false all rate of rise heat detectors do not automatically reset
False they do automatically reset
Heat detector that can monitor large areas. System of metal pneumatic tubing arranged over a wide area of coverage. Tubing acts as a pressurized air chamber as air expands it moves a flexible diaphragm
Pneumatic rate of rise line heat detector
Tubing in pneumatic rate of rise line heat detectors is limited to about 1000 feet in length. The tubing should be arranged in rows that are no more than how many feet apart and how many feet from walls
30 ft apart and 15 from walls
Heat detector that works on same principle as pneumatic rate of rise line. This detector is self-contained it one unit monitors a specific location
Pneumatic rate of rise spot heat detector
This heat detector is designed to be used in areas that are subject to regular temperature changes. Containing outer bimetallic sleeve with a moderate expansion rate. Two bowed struts are inside with a slower expansion rate than the sleeve
Rate compensation heat detector
Semiconductor made of substances that have a resistance that varies rapidly and predictably with temperature
Thermistor
Detectors with one or more thermistors. They change in electrical resistance when exposed to heat. Can be calibrated to function as a rate of rise approximately 15° per minute or fixed temperature
Electronic spot type heat detector
What percentage of fire deaths are attributed to smoke inhalation and not to Burns
65%
Preferred type of detector in many types of occupancies
Smoke detectors
Sometimes referred to as a physical products of combustion smoke detector
Photoelectric smoke detector
This smoke detectors works satisfactorily on all types of fires and usually responds work quickly to smoldering fires
Photo electric smoke detector
Smoke detector best suited for living rooms bedrooms and kitchen’s
Photoelectric smoke detector
Type of photoelectric detector using a beam of light focused across an area being monitored onto a receiving device
Projected beam application
Type of photoelectric detector that is particularly useful in buildings were large area of coverage is desired
Projected beam application
Type of smoke detector that contains a sensing chamber consisting of two electrically charged plates one positive and one negative, and radioactive source
Ionization smoke detector
Physical process of converting an Adam or molecule into an ion by adding or removing charged particles such as electrons
Ionization
What can cause a malfunction of an ionization detector
Changes and humidity and atmospheric pressure
Type of smoke detector that work satisfactorily on all types of fires although generally respond more quickly to flaming fires
Ionization smoke detector
Smoke detector best suited for rooms that contain highly combustible materials such as cooking grease newspapers flammable liquid paint cleaning solution
Ionization smoke detector
Type of ionization smoke detector that is designed to continuously monitor small amount of air from the protected area
Air sampling smoke detector
Type of detector that is a system of pipes in the ceiling of the protected area. A fan in the detector control unit draws air from the building and is then sampled using for electric sensor
Air sampling smoke detector
Sometimes called a light detector
Flame detector
Three types of flame detectors
UV.
IR.
Both
Type of detector that’s fast to respond to fires but also easily tricked I know on fire conditions like welding sunlight
Flame detector
Infrared flame requires what action of the flame before it sends an alarm
Flickering action of the flame
Some gasses released by fire may include
Water vapor h20 Carbon dioxide co2 Carbon monoxide Hydrogen chloride hcl Hydrogen cyanide hcn Hydrogen fluoride hf Hydrogen sulfide h2s
Only what gases are released from all carbonaceous material that burns
H20
Co2
And co
It is only practical for a fire gas detector to monitor levels of what gases
CO2. CO
A fire gas detector operates faster than a heat detector but not as fast as
A smoke detector
Devices used to supervise automatic sprinkler systems
Temper switches
Device for occupants to manually initiate the alarm.
Manual alarm initiating devices
Aka pull stations or pull boxes
Manual alarm systems depends on occupants for activation and therefore requires
The occupancy be occupied.
Pull stations are to be mounted on columns or walls so that the operable portion is no less than and no more than how high from floor
No less than 3.5’ and no more than 4.5’ from the floor
In all cases, travel distances to the pull station should not exceed how many feet
200’
Pull stations are required how far from every exit
Within 5’ of exits
Most building codes do not require manual pull stations when what is present
Automatic sprinklers wrinkles
Pull station that operates after a single motion is made from the user
Single action
Pull station that requires the operator to perform two steps in order to activate the alarm. Lifting a door the activating switch
Double action
Type of system installed in an occupancy depends on the following
Level of life hazard Structural features Hazard from building contents Availability of fire suppression resources. State local code requirement. Federal regulation.
Alarm system that is used to notify occupants of an emergency and direct them in the proper course of action
Emergency voice/alarm communications system
System that is used to connect fire alarm boxes or protected occupancy directly to the fire department
Parallel telephone system
Alarm system designed to transmit both a visible and audible alarm only in the immediate premises with no off-site reported
Protected premises/local
Three basic types of local alarm systems
Non-coated local alarm .
Zoned/annunciated alarm.
Addressable alarm system
Simplest type of local alarm system. When detector send signal to the control panel all of the alarm signaling devices operate simultaneously
Non-coded local alarm
An annunciator panel fire alarm control panel or print out should indicate the building floor fire zone or other area that coincides with the location of an operating initiating device. Easier for responders to identify location of activation
Zoned/annunciated alarm
Of the three types of protected promise/local alarm systems, this type is the most effective and becoming more prevalent
Addressable alarm system
Type of local alarm system where each initiating device is connected to a specific visible indicator on the alarm control or annunciator panel.
Addressable alarm system
Fire alarm system that is connected to a municipal fire alarm system transmitted over same manual fire alarm boxes on the street
Auxiliary fire alarm
Type of auxiliary fire alarm that has its own source of power does not depend on the supply source that powers the entire municipal fire alarm system
Local energy system
Type of auxiliary fire alarm that is electrically connected to an integral part of the municipal fire alarm system and depends on the system source of electric power
Shunt system
NFPA 72 allows what detection devices to be used on a shunt system
Only manual pull stations and waterflow detection.
Alarm system used to protect large commercial and industrial buildings high-rise structures, and groups of commonly owned buildings, such as a college campus or industrial complex in a single location. Each building has its own system all are wired to common receiving point in a separate structure remote from hazard
Proprietary alarm system
The primary difference between a central station system and a proprietary system is
The receiving point for alarms in a central station system is located outside the protected premises and monitored by contracted service
A remote receiving system is common in localities that are not served by
Central station systems
Remote receiving system is like an auxiliary system except
They’re attached through nondedicated fire department alarm lines. may use alternative monitor station like PD
Supplementary system placed in a facility in addition to other alarm signaling system. Purpose is to provide reliable communication for residents and firefighters
Emergency voice/alarm communication
Two basic types of emergency voice/alarm communication system
One Way system. Two way system
Emergency voice communication system that warns building occupants the action is needed and tells them what actions to take
One way system
Emergency voice alarm communication system that allows people at other locations in the building to communicate with the person at the main control station using either intercom or special telephones
Two-way system
Dedicated telephone line between each individual alarm box or protect the property and the fire department communication center
Parallel telephone system
Fire alarm test conducted when systems are installed are commonly called
Acceptance tests
Periodic testing the fire alarms is often referred to as
Service testing
What an be used to check restorable heat detectors
Heat gun or hair dryer
Non restorable pneumatic heat detectors should be tested how
Mechanically
The actual performance of the alarm system test is the responsibility of
The owner occupant. Or fire alarm company
Dry cell batteries, or lead acid and primary batteries, should be inspected how often
Monthly
Nicad and sealed lead acid batteries should be inspected how often
Semi annually
Reliability of the entire alarm system is entirely dependent on the reliability of what
The detection devices
When should automatic initiators be inspected.
After install
After a fire
recurring schedules
A permanent record of all detector and system tests must be kept by the AHJ for how long.
At least 5 years
Following minimum information should be included in the alarm test file
Date Detector type Location Type of test Result
For a non restorable fixed temp Heat detector, it cannot be tested periodically, and therefore must be tested when
15 years after install with 2% of them removed for lab testing
Restorable heat detectors should have one detector on each circuit tested how often
Semiannual
Fusible link detector with replaceable links should be checked by removing link and seeing if contacts close how often
Semi annually
Replaceable fusible links are recommended for replacement how often
Every 5 years
Pneumatic heat detectors should be tested with a heating device or pressure pump how often
Semi annually
Smoke detectors should be tested semi annually and sensitivity testing be performed when
After first year of service every two years after that
Flame and gas detection devices require testing from trained individuals. Inspectors are only responsible for
Witnessing the test.
Auxiliary devices a fire alarm panel may control are
Hvac fictions
Evac alarms
Fire dampers
