FIRE DETECTION, ALARM AND SUPPRESSION SYSTEMS FVCC Fire Rescue

FIRE DETECTION, ALARM AND SUPPRESSION SYSTEMS

FVCC Fire Rescue

OBJECTIVES

2-18.1 Identify the types of fire alarm systems and their components (3-3.13)

2-18.2 Identify the value of automatic sprinklers in providing safety to the occupants of a structure

2-18.3 Identify a fire department sprinkler connection and water flow alarm

OBJECTIVES

2-18.4 Identify the main control valve on an automatic sprinkler system and determine if it is open or closed.

2-18.5 Identify how the automatic sprinkler head activates and releases water.

2-18.6 Identify the components of a hood and duct system and it’s use.

2-18.7 Identify wet pipe and dry pipe systems and their uses.

OBJECTIVES

2-18.8 Identify the procedures to connect hose line(s) to a fire department connection of a sprinkler or standpipe system.

2-18.9 Identify the procedure of stopping the flow of water from a sprinkler head using a wedge or stopper.

OBJECTIVES

2-18.10 Identify the procedure of operating a main control valve on an automatic sprinkler system from “open” to “closed” and then back to “open”.

2-18.11 Identify the procedures of opening and closing the main drain valve on an automatic sprinkler system.

OBJECTIVES

2-18.12 Identify the procedures of reading and recording the indicated pressures on all gauges provided on a standard wet pipe automatic sprinkler system and identify each gauge.

2-18.13 Identify the procedures of reading and recording the indicated pressures on all gauges provided on a standard dry pipe automatic sprinkler system and identify each gauge.

OBJECTIVES

2-18.14 Demonstrate connecting hose line(s) to a fire department connection of a sprinkler or standpipe system.

2-18.15 Demonstrate stopping the flow of water from a sprinkler head using a wedge or stopper.

2-18.16 Demonstrate operating a main control valve on an automatic sprinkler system from open to closed and back to open.

OBJECTIVES

2-18.17 Demonstrate opening and closing the main drain valve on an automatic sprinkler system.

2-18.18 Demonstrate reading and recording the indicated pressures on all gauges provided on a standard wet pipe sprinkler system and identify each gauge.

OBJECTIVES

2-18.19 Demonstrate reading and recording the indicated pressures on all gauges provided on a standard dry pipe automatic sprinkler system and identify each gauge.

• IFSTA, Essentials, 4th ed, Chapter 15• Delmar, Firefighter’s Handbook, 2000, Chapter 12

Fire loss in the U.S. and CanadaU.S. Facts & Figures* (2001)

•Every 18 seconds, a fire department responded to a fire somewhere in the United States. •Public fire departments responded to 1,734,500 fires. These include 521,500 structure fires, 351,500 vehicle fires, and 861,500 outside and other fires. •In 2001, there were 6,196 civilian fire deaths; 2,451 of which were due to the events of September 11. Exclusive of the events of September 11, an estimated 3,745 civilian deaths occurred, a decrease of 7% from the previous year.•In 2001, home fires caused 3,110 or 83% of civilian fire deaths, exclusive of the events of September 11. This is a 9% decrease, making it the second lowest home fire death total since NFPA´s fire experience current survey methodology started in 1977. Nationwide, there was a civilian home fire death every 170 minutes. •Nationwide, there was a civilian fire injury every 26 minutes. There were an estimated 21,100 civilian fire injuries, of which 15,200 occurred in homes.

But the single-station, battery-powered smoke alarm we know today became available to consumers in the 1970s, and since then, the home fire death rate has been reduced by half. NFPA estimates that 94% of U.S. homes have at least one smoke alarm today, and most states have laws requiring them in residential dwellings. •15 of every 16 homes (94%) in the U.S. have at least one smoke alarm. •One-half of home fire deaths occur in the 6% of homes with no smoke alarms. •Homes with smoke alarms (whether or not they are operational) typically have a death rate that is 40-50% less than the rate for homes without alarms. In three of every 10 reported fires in homes equipped with smoke alarms, the In three of every 10 reported fires in homes equipped with smoke alarms, the devices did not work. Households with non-working smoke alarms now outnumber devices did not work. Households with non-working smoke alarms now outnumber those with no smoke alarms. those with no smoke alarms. Why do smoke alarms fail? Most often because of missing, dead or disconnected batteries.

FIRE ALARM SYSTEMS & COMPONENTS

Fire alarm systems Protected premises fire alarm

systems (local) Most basic Designed to only be initiated

manually


Automatic alarm systems Transmits a signal to an off-site location to summon the

fire department Produces an automatic response upon activation of local

alarm Signals thorough dedicated wire pairs, leased telephone

lines, fiber-optic cable, or wireless communication links


Transmission of alarm to fire department may be accomplished by the following means: Auxiliary system – transmitted immediately and

directly to the fire department. Uses municipally owned/controlled circuitry.

3 Types: Local Energy System, Shunt System, Parallel Telephone System.

Municipal Master Box is an example of a Local Energy System


Remote station system Connected to fire department

directly or through an answering system

Transmitted by leased telephone lines or radio signal on a dedicated frequency

Must have the ability to transmit a trouble signal to fire alarm center, if system is impaired

May be monitored by an entity other than the fire department

A remote system must be capableof transmitting a trouble signal if the

system is impaired


Proprietary system Used to protect large commercial or industrial

buildings or multiple buildings at a single location Each building or area has own alarm system wired to a

single receiving point located within the complex Receiving point must be in separate, non-hazardous

area Must be constantly staffed by trained personnel Monitoring personnel must be able to summon fire

department through alarm system or by phone


Central station system Similar to proprietary system but monitored off-site

contracted service point called a central station Upon alarm initiation, central station employee obtains

information and notifies appropriate emergency response agency

Usually includes notifying fire department and property representative

Usually connected by supervised telephone lines


Four basic types of automatic alarm-initiating devices Heat detectors

Fixed temperature heat detectors Relatively inexpensive Least prone to false

activations Detect heat by: expansion of

heated material, melting of heated material and changes in resistance of heated materials


Types:Fusible Devices/ Frangible BulbsContinuous Line DetectorBimetallic Detector

Fusible Fixed Temperature Heat Detector Fusible Fixed Temperature Heat Detector

Detect Heat over a linearArea parallel to the detector

Insulations loses some of its resistance at a predeterminedtemperature anywhere along the line. This causes current flow between the 2 components,initiating the alarm.

This type uses 2 insulated wires withinan outer covering. When the rated temperature is reached, the insulation melts and allows the 2 wires to touch.


Rate of rise heat detectors Operates on principle that room temperature will rise

faster from a fire than from atmospheric temperature change

Usually designed to initiate an alarm when increase in temperature exceeds 12 degrees to 15 degrees F. per minute

Being initiated by sudden rise in temperature, regardless of initial temperature, it can initiate an alarm at temperatures much lower than required by a fixed-temperature detector

Automatically resets, if not damaged 4 Types: pneumatic rate-of-rise spot detector, pneumatic

rate-of-rise line detector, rate-compensated detector, and thermoelectric detector

Rate-of-rise spot heat detector

Pneumatic rate-of-rise heat detector

Cutaway of a rate-compensated heat detector

Thermoelectric heat detector

Operates when 2 wires of Operates when 2 wires of different different Material are twisted together Material are twisted together and and Heated at one end, an electric Heated at one end, an electric current is generated at the current is generated at the other end. other end. The The rate rate at which the wire are at which the wire are heated determines the amount heated determines the amount of current that is generated. of current that is generated. These detectors are designed These detectors are designed to “bleed off” or dissipate small to “bleed off” or dissipate small amountsamountsof current. of current.


Smoke detectors can initiate an alarm much more quickly due to smoke, not heat, being generated. Photoelectric

Uses a photoelectric cell with a specific light source by either beam application or refractory applications

More sensitive to smoldering fires Powered by battery, household current, or household

current with battery backup


Ionization Uses a small amount of radioactive material to ionize

air molecules Products of combustion interrupt electrical charge

within chamber, causing alarm More responsive to flaming fires Powered by battery, household current, or household

current with battery backup


Flame detectors Type that detects light in the ultraviolet wave spectrum Type that detects light in the infrared wave spectrum Those that detect both types of light

UV Flame Detector: The UV sensor has been carefully selected to ensure the greatest degree of spectral matching to the radiant energy emissions of fire.

IR Flame Detectors From Detector ElectronicsInfrared detectors respond to flaming fires emitting light in the infrared portion of the spectrum. IR detectors can respond to a fire condition in less than 50 milliseconds. These detectors are designed to alarm to hydrocarbon fires, while ignoring things like arc welding, nuclear radiation and x-rays. IR detectors are available in single wavelength or dual wavelength. Both normal and high speed versions are available.

X5200 UVIR Flame Detector Advanced detection capabilities and immunity to extraneous sources.

The mounting arrangement allows the UV and IR sensors to monitor the same hazardous location with a 90 degree cone of vision.

When both sensors simultaneously detect the presence of a flame, an alarm signal is generated. The detector has Division and Zone explosion-proof ratings and is suitable for use in indoor and outdoor applications.

Automatic, manual or magnetic optical integrity testing


Fire/Gas detectors• Measure carbon dioxide and carbon monoxide produced by

fire• More discriminating than other detectors• Designed to be sensitive to only gases produced by specific

hostile fire activity and to ignore gases produced by constructive gases.


Identify the value of automatic sprinklers in providing safety to the occupants of a structure 2-18.2 Discharges water directly on fire Operates while fire is small (incipient phase) Products of combustion are limited Effective in preventing fire spread to upper floors Provides a better chance of survival for occupants

of upper floors

VALUE OF AUTOMATIC SPRINKLERS

Discharges water directly on fire Operates while fire is small Products of combustion are limited Effective in preventing fire spread to upper floors Provides a better chance of survival for occupants of upper

floors (By cooling the fire gases rising from the fire, the sprinkler prevents the fire from reaching the flashover stage.)

Fire records show that 93 percent of of fires are handled by only one sprinkler. (In the remaining cases, two sprinklers handled an additional four percent. It took three sprinklers to handle nearly all of the remaining 3 percent.)

VALUE OF AUTOMATIC SPRINKLERS

Sprinklers are the most effective fire safety device ever invented.

Look at this comparison with smoke alarms and with no fire protection at all.

The National Fire Protection Association reports that people with smoke alarms in their home have a 50 percent better chance of surviving a fire.

Adding sprinklers and smoke alarms increases your chances of surviving a fire by over 97 percent.

•The threaded end screws into a water pipe in the ceiling and is not visible from below. •The cap seals the opening and prevents water from flowing out. The glass bulb holds the cap/seal in place.•The glass bulb is filled with liquid. •Heat from a fire expands the liquid, which breaks the bulb. The cap/seal falls away and water will stream out. •The water stream hits the deflector, which breaks it into a spray of tiny droplets.

FIRE DEPARTMENT SPRINKLER CONNECTION

Water flow alarm Located outside the building usually close to the

sprinkler connection Indicates that water is flowing through the system Operated either hydraulically or electrically

FIRE DEPARTMENT SPRINKLER CONNECTION

Fire department connection Located outside the building Is usually a siamese connection with two 2 ½ inch

female connections with a clapper valve or one clappered large-diameter inlet

Used to connect supply lines to the sprinkler system

MAIN CONTROL VALVE

Used to cut off the water supplyLocated between source and sprinkler system

Most often located under alarm valve or outside near the system controls

MAIN CONTROL VALVE

Outside screw and yoke (OS & Y) Open when the word “OPEN” is visible in window

Post indicator Open when the word “OPEN” is in the window

Wall post indicator Open when the word “OPEN” is in the window

Post indicator valve assembly Has a sight area that is open then the valve is

open or may have an indicating paddle Valve is a butterfly valve

Small OS&Y Valve

Post Indicating Valve (PIV) Post Indicating ValveAssembly (PIVA)

Wall Post Indicating Valve (WPIV)Wall Post Indicating Valve (WPIV)

AUTOMATIC SPRINKLER HEAD

Fusible link Fusible link, holding two levers together, is melted

during fire Levers and caps are pushed out of the way by water Water stream strikes the deflector and is converted

into a spray


Glass bulb Small bulb is filled with liquid and air bubble

is heated by fire until bulb shatters The cap is pushed out of the way by water Water stream strikes the deflector and is

converted into a spray


Chemical pellet Pellet of solder under compression melts

during fire Plunger moves down releasing valve cap

parts Water stream strikes the deflector and is

converted into a spray


Quick release Specially designed fusible link with greater surface area

absorbs heat faster and responds quicker


Sprinkler Position:PendantUprightSidewallSpecial-purpose

Pendant

Upright

Sidewall

Special Purpose

Used in specific applications because of their unique characteristics.

Several Types for special areas & uses. Corrosive Coatings Recessed into Ceilings

Sprinkler Storage

Storage Cabinet for housing extra sprinklers and a sprinkler wrench should be installed by the sprinkler system.

Normally, these cabinets hold a minimum of 6 sprinklers and a sprinkler wrench in accordance with NFPA 13 & 13D.

The function of changing sprinklers is performed by representatives of the building who are qualified to perform the work on sprinkler systems.

HOOD AND DUCT SYSTEM

Used for local application, meaning only portion of building, directly where the hazard exists Restaurant cooking areas Laboratory hood systems Paint booths Other hazardous areas

HOOD AND DUCT SYSTEM

Uses a heat sensitive device (such as a fusible link) or manually activated switch for activation

Extinguishing agents may be: Fine water spray Dry chemical Wet chemical Carbon Dioxide (CO2) Halogenated or clean agents

WET & DRY PIPE SYSTEMS

Wet pipe system Used in location where piping will not be subjected to

temperatures below 40 degrees F. (4 degrees C) Maintains water under pressure at all times Connected to the public water supply so fused

sprinkler can discharge a water spray in area while sounding alarm

Both sides of control valve have pressure gauges to indicate water pressure of the supply and of the system System side pressure should read slightly higher than

supply side pressure


Dry pipe system Used in location where piping is subjected to

temperatures below 40 degrees F (4 degrees C) All pipes are pitched to drain system back to

main drain Air under pressure replaces water in piping

above the dry-pipe valve When sprinkler fuses, pressurized air escapes

first, and dry-pipe valve opens to allow water into piping system


Quick opening devices are installed in systems with water capacity over 500 gallons to accelerate the opening of the dry-pipe valve.

The dry pipe valve is equipped with an air pressure gauge above the clapper and a water pressure gauge below the clapper The air pressure gauge will read substantially lower than

the water pressure gauge If the gauges read the same, this is an indication the

system has been tripped and water has entered the pipes

CONNECTING HOSELINES

Locate fire department connectionSelect proper type and amount of hoseAdvances hose to fire department connectionRemoves cover from fire department

connectionsChecks fire department connection for

damage or obstructionsConnects hose to fire department connection

CONNECTING HOSELINES

Connects hose to proper discharge outlets on pumper

Notifies officer or pumper engineer that connection has been completed

STOPPING THE FLOW OF WATER

Wooden wedges Positions ladder close to sprinkler head With someone supporting ladder, climbs to a height

that the sprinkler head can be reached Insert one or more wedges Tap until flow of water stops or diminishes to a trickle

STOPPING THE FLOW OF WATER

Commercial stopper Positions ladder close to sprinkler head With someone supporting ladder, climbs to a

height that the sprinkler head can be reached Inserts the stopper between the orifice and the

deflector If the operation of some type of device is

necessary to open the stopper, operates it at this time until the flow stops or diminishes to a trickle

OPERATING A MAIN CONTROL VALVE

Outside screw and yoke (OS & Y) valve Unlock any means to secure the valve in the open

position and remove it Grasp the wheel and slowly turn it until the yoke

completely disappears When instructed to do so, turn the wheel slowly until

the yoke is extended as far as possible Secure the valve in the “OPEN” position

OPERATING A MAIN CONTROL VALVE

Post Indicator Valve (PIV) Unlock any means used to secure the valve in the

open position and remove it Remove the handle and place it on the operating

nut Slowly rotate the operating nut until the word

“CLOSED” can be seen in the window When instructed to do so, rotate the operating

nut slowly until the word “OPEN” can be seen in the window

Secure the valve in the open position

OPENING & CLOSING THE MAIN DRAIN VALVE

If main valve is an OS & Y valve: To open: Turn handle slowly until stem is fully

extended To close: Turn handle until stem is no longer

visibleOther types of valves (globe, butterfly, etc):

Turn handle slowly to fully “OPEN” position Turn handle slowly to fully “CLOSED” position

READING & RECORDING INDICATED PRESSURES

Note: Perform this evolution according to the type of system being used in the exercise.

Read and record water pressure on supply side Read and record water pressure on system side

Homework

a. Deflector

b. b. frame arms

c. lever arms

d. Release Mechanism (Fusible Link)

e. valve cap

1.

2.

3.

4.

5.

Homework

a. Chemical Pellet

b. Frangible Bulb

c. Fusible Link (Quick Response)

d. Fusible Link (Standard)

6.

9.

7.

8.

Homework

VS 15-3

a. Pendant

b. Sidewall

c. Upright

10. 11.12.

Homework

a. Main Control Valve (OS&Y) b. OS&Y (Outside Screw and Yoke) c PIV (Post Indicator Valve) d. PIVA (Post Indicator Valve Assembly)e. WPIV (Wall Post Indicator Valve)

13. 14. 15.

16.

17.

Homework

Select facts about a sprinkler system’s fire department connection. Write the correct letters on the blanks.

18. Which of the following best describes the basis for establishing a minimum flow rate?

a. Hazard being protected and its volatility b. Number of occupants in the building

c. Available water supply and private pipe diameters d. Hazard being protected, occupancy, and building contents

19. At what residual pressure must a minimum water supply be able to deliver the required volume of water to the highest sprinkler in a building?

a. 15 psi b. 30 psi c. 20 psi d. 25 psi20. When does a sprinkler system need an outside source of water and pressure?a. In a chemical fireb. During a large fire or when a pipe breaksc. When some of the system pipes are frozen due to extreme coldd. During an electrical fire21. What type of valve prevents water from flowing from a sprinkler system back

into a fire department connection?a. Check b. Globe c. Main d. Stop22. Firefighter A says that a fire department connection to a sprinkler system may

consist of a siamese with at least two 2½-inch (65 mm) female connections with a clapper valve.Firefighter B says that a fire department connection to a sprinkler system may be a large-diameter connection with a clappered inlet.Who is right?

a. Firefighter A b. Firefighter B c. Both A and B d. Neither A nor B

Homework23. Why would a ball drip valve be installed at a fire department connection?a. To ease back pressure against the check valveb. To keep the connection and check valve dry and functional during freezing conditionsc. To release excess water from the systemd. For relief of pressure against the main valve24. What is the minimum recommended pump capacity for a pumper supplying

a sprinkler system?a. 1,500 gpm b. 2,000 gpm (8 000 L/min) c. 2,500 gpm d. 1,000 gpm25. Firefighter A says that the water supply for a sprinkler system is designed

to supply all of the sprinklers actually installed on the system.Firefighter B says that fire department pumpers supporting sprinkler systems should operate from the main that is supplying the sprinkler system.Who is right?

a. Firefighter A b. Firefighter B c. Both A and B d. Neither A nor B26. How can firefighters determine the proper direction of water flow through a

check valve?a. By arrows on the valve or the appearance of the valve castingb. By the name of the manufacturerc. By the check valve flow designation stamped on the valve castingd. By the stamped metal instruction tag chained to the valve casting

Homework

Select facts about guidelines for operations at sprinkler-protected properties. Write the correct letters on the blanks.

27. Which of the following is not a recommended method of insuring adequate water supply to a sprinkler system?

a. Limit the use of direct hoselines from the water supply system serving the sprinkler system.

b. Establish a second water supply for hoselines if necessary.c. Increase sprinkler discharge by increasing the pressure on the system.d. Shut off water supply to individual sprinkler heads as soon as firefighters

begin their attack.28. What action should be taken when a sprinkler control valve is closed?a. A firefighter with a portable radio should be stationed at the valve.b. All pumpers should be disconnected from the fire department connection.c. Firefighters should service damaged sprinklers and system components.d. The control valve should be secured shut and tagged.29. Which of the following is a proper method for stopping the flow of water

from a single sprinkler?a. Shut off the water supply for that section of the system.b. Shut off the water supply for the whole system.c. Insert a wood wedge between the deflector and the discharge orifice.d. Reinsert the sprinkler release plug into sprinkler orifice.

Homework

30. When should sprinkler control valves be closed?a. Before firefighters begin their attackb. Not until the fire is completely extinguishedc. Not until fire officers are convinced that further operations will

simply waste water, produce heavy water damage, or hamper final extinguishment

d. When firefighters leave the premises31. When should pumpers be disconnected from the system?a. As soon as fire officers determine the system is operating at full

volumeb. Not until extinguishment has been determined by thorough overhaulc. As soon as the fire is under controld. Not until fire officers are convinced that further operations will

simply waste water, produce heavy water damage, or hamper final extinguishment

Homework

Match types of alarm-initiating devices to their descriptions. Write the correct letters on the blanks.

32. __ Is activated when heat causes solder to melt so that an electrical circuit is closed

33. __ Is activated when heat causes a bubble in a glass vial to expand until the bulb fractures so that an electrical circuit is closed

34. __ Consists of a length of cable that reacts to heat by changing electrical resistance or by making electrical contact when wire insulation melts

35. __ Uses a component made of two different types of metal that expand at different rates

36. __ Uses the expansion of heated air in a chamber to force a metal diaphragm against contact points

37. __ Uses the expansion of heated air in tubing to create an electrical connection

ANSWER BANKa. Bimetallic Detector b. Continuous Line Detector Tubing Type c. Fusible Detector d. Pneumatic Spot Detector e.

Thermoelectric

Homework

38. Uses two bowed struts inside a metallic sleeve so that it can be activated either by the expansion of the struts or the expansion of the sleeve

39. Is activated when two twisted wires of dissimilar metals are heated, producing an electrical current

40. Uses a light source and a receiver and is activated when smoke breaks the light beam

41. Uses an internal lamp, the light of which is diffused by smoke so that it contacts a photocell

42. Uses a radioactive material to ionize air molecules within a chamber to allow electrical flow until smoke makes the air less conductive

a. Continuous Line Detector Wire Type b. Ionization- Chamber Smoke Chamberc. Photoelectric Smoke Detector Beam Typed. Photoelectric Smoke Detector Refractorye. Pneumatic Line

Homework

Select facts about heat detectors. Write the correct letters on the blanks.43. The normal location for a fixed-temperature heat detector is ___.a. Over the facility doors c. High in the roomb. Near the baseboards of the walls d. At a mid-height level in the room44. Which of the following is not one of the principles of physics used to

detect heat in fixed-temperature devices?A. Expansion of heated material b. Melting of heated material c. Changes in electrical resistance of heated materiald. Contraction of heated material45. Firefighter A says that fixed-temperature heat detectors are the type

of detectors least likely to produce false activations.Firefighter B says that a fixed-temperature heat detector is the slowest detector to activate.Who is right?

a. Firefighter A b. Firefighter B c. Both A and B d. Neither A nor B

46. A detector that monitors a single area is referred to as a ___ detector?

a. Fusible b. Frangible c. Continuous line d. Spot

Homework

47. Which of the following is not true of rate-of-rise heat detectors?a. They should be placed near exterior doorways.b. They typically respond to rates of rise that exceed 12 to 15 degrees

Fahrenheit per minute.c. They are reliable and are not subject to false activations.d. They automatically reset if undamaged by the fire.48. What is the recommended maximum length of tubing in pneumatic

rate-of-rise line detector systems?a. 1,000 feet b. 100 feet c. 30 feet d. 15 feet49. Which of the following statements is true? The purpose of rate

compensation in heat detectors is to eliminate the need for having a fixed

a. temperature at which the alarm will activate.b. The wires of a thermoelectric detector must be made of the same

kind of metal in order for the system to produce electric current.c. Fixed-temperature heat detectors should have an activation

temperature slightly above the highest expected temperature for the room.

d. Because of their high reliability, the use of frangible-bulb detectors continues to grow in popularity for light industrial applications.

Homework

Select facts about smoke detectors. Write the correct letters on the blanks.50. Alarms that use light to detect products of combustion are referred to as

___.a. Photoelectric smoke detectors c. Ionization smoke detectors b. Rate-compensated detectors d. Flame detectors 51. Photoelectric detectors are generally more sensitive to ___ than are

ionization detectors.A. Smoldering fires b. Flaming fires c. Fire gases d. Invisible products of combustion

52. Which of the following statements is true?a. Ionization smoke detectors are not recommended for residential properties

because of the radioactive material they contain.b. After activation, ionization smoke detectors must be taken to a service

center to have the collector electrodes restored.c. Smoke detectors respond quickly.d. Most smoke detectors also contain sensors for detecting high levels of

carbon monoxide.53. Smoke detectors are normally powered by ___.

A. Photocells b. Ionization chambers C. Bimetallic solar cells d . Household current or batteries

Homework

54. The most common reason for failure of a smoke detectors is ___.a. Excessive heat prior to the generation of enough smoke to activate

the alarmb. Power failures in household circuitsc. Poor maintenance of batteriesd. Failure to change the radioactive material twice per year55. Firefighter A says that beam-application smoke detectors are not self-resetting.

Firefighter B says that photoelectric smoke detectors are not self-resetting.

Who is right?a. Firefighter A b. Firefighter B c. Both A and Bd. neither A nor B

HomeworkComplete statements about flame detectors.

Select the correct word for the blanks. 56. __ (a. Ultraviolet, b. Infrared) flame detectors

may be sensitive to sunlight.57. __ Flame detectors must have an (a. unobstructed, b. overhead) view of the fire

site.58. __ (a. Ultraviolet, b. Infrared) flame detectors

may be sensitive to welding equipment or mercury-vapor lamps.

59. __ Most IR detectors are designed to require (a. steady, b. flickering) light.

Homework

Complete statements about fire-gas detectors. Select the correct words for the blanks.

60. __ Fire-gas detectors are the (a. most, b. least) common type of fire detector.

61. __ All fires release water vapor, carbon dioxide, and (a. oxygen, b. carbon monoxide).

62. __ Fire-gas detectors will initiate an alarm (a. faster, b. slower) than a heat detector.63. __ Fire-gas detectors can be (a. more, b. less)

discriminating than other types of detectors.

Homework

Match types of automatic alarm systems to their descriptions. Write the correct letters on the blanks.

64. An auxiliary alarm system within an occupancy that is attached directly to a hard-wired or radio-type municipal fire alarm box

65. An auxiliary alarm system in which the municipal alarm circuit extends into the protected property

66. An auxiliary alarm system that transmits alarms from the protected property to the alarm center over a municipally controlled telephone circuit

a. Local energy system

b. Parallel telephone system

c. Shunt system

67. A system that connects to the telecommunications center or answering service through a means other than the municipal fire-alarm-box system

68. A system that provides coverage to a large building or complex of commonly owned buildings connected to a monitoring station

69. A system that provides coverage to several sites connected to an off-site contracted service

Homework

a. Central station system

b. Proprietary system

c. Remote station system

Homework

Select facts about supervising fire alarm systems. Write the correct letters on the blanks.

70. Fire alarm systems are designed to be ___.A. Self-supervising b. Maintained with no more than weekly inspectionc. Maintained with no more than daily inspectiond. Inspected through the use of an operator-initiated signal issued each hour71. Self-diagnosing systems with built-in microprocessors provide test results on

___.a. Request of the system supervisor b. Punched tape c. A printer or

computer screen d. Microchips72. Firefighter A says that control panels for manual pull stations must be listed by

a testing laboratory for this purpose.Firefighter B says that control circuits for suppression systems that use manual pull stations or automatic detection devices do not need to be supervised.Who is right?

a. Firefighter A b. Firefighter B c. Both A and B d. Neither A nor B73. By regulation, carbon dioxide systems are required to have a ___.a. Motion sensor to detect the presence of people b. Smoke detector system c. Back-up sprinkler system d. Predischarge alarm74. Water flow alarms are normally set to respond to flow equal to that of ___.A. One sprinkler b. Two sprinklersc. One-tenth of the system d. One-half of the system

Homework

Complete statements about water flow alarms. Select the correct word for the blanks.

75. (a. Hydraulic, b. Electric) water flow alarms are local systems that alert personnel in the building and passersby.

76. Water flow alarms are actuated by the flow of (a. electricity, b. hydraulic fluid, c. water).77. (a. Hydraulic, b. Electric) water flow alarms use water

in the system to branch off to a water motor to drive a local alarm gong.

78. (a. Hydraulic, b. Electric) water flow alarms can be connected to systems to notify the fire department.

Homework

Match sprinkler system applications to their descriptions. Mark the correct letters on the blanks.

79. Used in locations that will not be subjected to temperatures below 40°F (4°C)

80. Used in locations that may be subjected to temperatures below 40°F (4°C)

81. Used when it is important to prevent water damage even if the pipes are broken

82. Used to wet down an area through the use of open sprinkler heads83. Used in one- and two-family dwellings

a. Delugeb. Dry-pipec. Preactiond. Residentiale. Wet-pipe

Documents

FIRE DETECTION, ALARM AND SUPPRESSION SYSTEMS FVCC Fire Rescue