Fires and Extinguishing Media, Portable, Electrical
A reducing agent or fuel could be a) carbon monoxide b) a heavy metal oxide c) hydrogen peroxide d) concentrated sulphuric acid e) chlorine
a
An example of a class "C" fire would be a) a fire in an electrical panel b) a fire in a trash bin c) a fire in a fuel tank d) a precious metals fire e) a fire in a coal storage pile
a
Foam extinguishers are recommended for a) Class "A" and Class "B" fires b) Class "A" and Class "C" fires c) Class "C" and Class "B" fires d) Class "D" fires e) Class "C" and Class "D" fires
a
Halon agent extinguishers are operated and applied in the same manner as a a) carbon dioxide extinguisher b) water extinguisher c) dry chemical extinguisher d) foam extinguisher e) dry powder extinguisher
a
Overheating of electrical equipment is a) the most common cause of fires in buildings b) usually the result of inadequate wiring c) often due to over-sized fuses being installed d) the result of blocked cooling fin passages e) illegal in most provinces
a
Carbon dioxide extinguishers a) are self-expelling b) are the best for Class A fires c) are the quietest in operation d) present no hazards during use e) are the most difficult to use
a
Foam extinguishers are recommended for a) Class "A" and Class "B" fires b) Class "A" and Class "C" fires c) Class "C" and Class "B" fires d) all classes of fires e) all but burning liquids
a
Halon from halon fire extinguishers a) produces a distinct odour which warns of the presence of halon b) is abrasive to electrical equipment c) will act as a conductor if moisture is present d) is derived from bromine, fluorine, or chlorine e) is corrosive
a
A Class "A" fire would involve a) gasoline or oil b) any dry materials c) paint or grease d) electrical equipment e) wood or coal
e
Electrical circuit insulation a) will never break down or deteriorate b) requires replacement after 10 years c) is not affected by temperature d) will not burn e) will deteriorate due to high temperatures
e
A class B fire is best extinguished by a) lowering the temperature of the burning wood or paper b) wetting the burning paper or wood c) smothering the burning liquid d) lowering the temperature of the burning liquid e) creating a chain reaction between the molecules of the burning material
c
A "loaded stream" extinguisher is one which a) can be used on Class B fires b) has an antifreeze agent c) is always under stored pressure d) is meant for Class C fires e) produces foam
b
Under the Canadian Electrical Code, if an area contains hazardous concentrations of flammable gases or vapours under normal conditions, electrical equipment must be designated safe for use in an area classification of a) Class 1, division 1 b) Class 1, division 2 c) Class 2, division 1 d) Class 2, division 2 e) Class 3, division 1
a
According to the Canadian Electrical Code an area where easily ignited material fibres capable of producing combustible flyings are handled or manufactured would be classified as a a) Class 1, division 1 b) Class 1, division 2 c) Class 2, division 1 d) Class 2, division 2 e) Class 3, division 1
e
Foam type fire extinguishers should only be installed or stored in areas where the temperature remains above a) 15 degrees C b) 12 degrees C c) 10 degrees C d) 7 degrees C e) 5 degrees C
e
Halon extinguishers are mostly intended for use on a) Class A fires b) Class B fires c) Class C fires d) Class A and B fires e) Class B and C fires
e
The fire extinguisher to be used on electrical equipment will be marked with a "C" on a background consisting of a a) blue circle b) green triangle c) yellow star d) green circle e) red square
a
What type of fire should be put out with water? a) Class "A" b) Class "B" c) Class "C" d) Class "A", "B", and "C" e) Class "D"
a
A red square on a fire extinguisher indicates that this extinguisher is suitable for a Class a) A fire b) B fire c) C fire d) D fire e) E fire
b
Dry chemical fire extinguishers should not be used where delicate electrical equipment is involved because it is a) conductive b) an insulator and can be corrosive c) always corrosive d) impossible to clean the equipment, it must be replaced e) capable of producing toxic fumes
b
Electrical connections a) need only make contact, they need not be tight b) will create large amounts of heat if not tight c) can cause an arc if too tight d) may operate on overload for specified durations e) will not generate heat at any time
b
Foam type fire extinguishers achieve best results by a) lobbing the foam over top of the fire b) bouncing the foam off the floor just in front of the burning area c) discharging the agent with a sweeping motion d) discharging the agent at the base of the flame e) splashing the agent into the burning liquid
b
Halon agents are a) safe until they make contact with the combustion process b) themselves toxic c) the most highly recommended for Class B:C use d) able to maintain cylinder pressure themselves regardless of temperature e) gradually replacing dry powder units
b
Pressure range in a carbon dioxide extinguisher is a) 31 to 55 kPa b) 5.6 to 6.3 Mpa c) 5,600 to 6,300 Mpa d) 31 to 55 Mpa e) 56 to 63 psi
b
The best portable fire extinguisher to use on a Class "D" fire is the a) carbon dioxide unit b) dry powder unit c) aqueous film-forming foam unit d) Halon unit e) dry chemical unit
b
The best type of fire extinguisher to use on an electrical fire would be a a) dry chemical extinguisher b) carbon dioxide extinguisher c) FF extinguisher d) dry powder extinguisher e) foam extinguisher
b
When an electrical fire is discovered a) the equipment may be left running if the fire is put out with a C type fire extinguisher b) the equipment should be de-energized as quickly as possible c) the equipment should be left running until a backup power supply is available d) the equipment may be immediately restarted once the fire is extinguished e) fresh air should be provided to the room as quickly as possible to get rid of toxic fumes
b
Which of the following extinguishers would ordinarily be used to combat a Class "C" fire? 1. carbon dioxide 2. foam 3. dry chemical 4. water a) 1, 2 b) 1, 3 c) 2, 3 d) 2, 4 e) 1, 4
b
You discover that a small fire has been started in a high tension switch box. In your immediate area there are four different types of fire extinguishers. The one you put the fire out with should be the a) soda - acid extinguisher b) dry chemical extinguisher c) chemical foam extinguisher d) cold water extinguisher e) one closest to you
b
A major disadvantage of a floor standing pump extinguisher over a backpack pump unit is a) the floor unit has only half the capacity b) the backpack unit has twice the range c) pumping must stop for relocation d) the floor unit pump is single acting e) the floor unit is too difficult to move
c
All maintenance work done on portable fire extinguishers is required to be a) completed on all extinguishers in the plant at the same time b) performed at the worksite in case they are required for emergency service c) contracted out to a certified service company d) supervised by a National Fire Protection Association
c
Combustion a) is endothermic and can occur in an inert atmosphere b) is always a visible process in that light is given off c) is exothermic, self sustaining, and can occur in an inert atmosphere d) always requires a source of ignition e) requires the presence of air
c
Dry chemical fire extinguishers may be used to extinguish electrical fires, however, they are not the best choice because they a) fail to cool the fire sufficiently b) conduct electricity c) leave a residue on the equipment d) produce toxic chemicals that may be flammable e) are not made in sizes large enough to fight electrical fires
c
During annual turnaround of a facility it is highly recommended that a) all fuses in the electrical system be replaced b) aluminum wiring be replaced c) all electrical connections be checked for tightness and corrosion d) all circuit breakers be disassembled and cleaned e) a megger be used on all electric motor windings
c
Temporary electrical hook-ups should a) be in place for a maximum duration of 72 hours only b) be made with BX electrical cable c) be designed to the original specifications d) comply with the ASME codes e) have CSA pre-approval
c
Under the Canadian Electrical Code, if an area contains dust in the air, under normal operating conditions, in concentrations high enough to produce explosive or ignitable mixtures, the electrical equipment must be designed safe for use in an area classification of a) Class I, division I b) Class I, division II c) Class II, division I d) Class II, division II e) Class III, division I
c
Your first reaction to a fire should be to a) fight it b) contain it c) turn on the alarm d) get the nearest fire extinguisher e) phone the maintenance department
c
A common cause of an electrical fire is a) allowing motors or conductors to get wet if not designed for that purpose b) prematurely replacing deteriorated wiring c) following too closely to the Electrical Code when installing electrical equipment d) replacing burned fuses with ones of the same rating e) waiting a specified amount of time between attempts to start large motors
d
An extinguisher with a 4 rating is a) good for Class C fires only b) twice as effective as a unit with a 1 rating c) not to be used on a Class A fire d) four times as effective as a unit rated 1 e) good for four minutes of use
d
Burning metals may be extinguished using a) dry chemical extinguishers b) carbon dioxide extinguishers c) AFFF extinguishers d) dry powder extinguishers e) foam extinguishers
d
Fuels or reducing agents which burn in the flaming mode only are a) flammable liquids b) coals c) flammable gases d) flammable liquids and gases e) cokes
d
Rating numerals to indicate the effectiveness of an extinguisher are used in reference to a) Class A fires b) Class B fires c) Class C fires d) Class A and B fires e) Class A, B, and C fires
d
The major advantage of carbon dioxide as a fire extinguishing agent for fires in electronic equipment is it a) has superior cooling ability over other agents b) is non-toxic c) does not reduce the oxygen content of the area d) does not leave a residue e) provides a barrier between the oxygen and burning components
d
To extinguish a fire, aqueous film-forming form extinguishing agents act in order to: 1. seal vapours 2. cool 3. remove the oxygen 4. break the chain reaction a) 4 b) 2, 3 c) 1, 2 d) 1, 2, 3 e) 1, 2, 3, 4
d
Water is the best extinguisher for a) an oil fire b) a gas fire c) an electrical fire d) a wood fire e) a metal burning fire
d
Which of the following constitutes a Class "C" fire? a) fire in a coal bunker b) fire in a fuel tank c) fire in a lumber pile d) fire in an electrical panel e) fire in a pile of paper
d
Wood can continue to burn in the flameless or glowing mode when oxygen level is as low as a) 17% b) 12% c) 8% d) 5% e) 3%
d
A process which causes fires to endure and renew themselves is a) temperature b) a reducing agent c) an oxidizing agent d) a flame e) molecular activity due to high temperature
e
Halon extinguishing agents extinguish a fire by a) cooling below ignition temperature b) radiation shielding c) isolating the fuel by coating d) removing the oxygen supply e) breaking the uninhibited chain reaction
e
One type of extinguisher suitable for extinguishing all four classes of fires is the a) Halon extinguisher b) foam extinguisher c) dry chemical extinguisher d) carbon dioxide extinguisher e) none of the above
e
The background symbol used on a fire extinguisher for a Class "D" fire is a a) green triangle b) green circle c) red square d) blue circle e) yellow star
e
The best type of fire extinguisher to use on a live electrical fire is a a) pressurized water extinguisher b) dry chemical extinguisher c) purple K extinguisher d) AFFF extinguisher e) carbon dioxide extinguisher
e
The maximum storage temperature for a carbon dioxide extinguisher is a) 31 degrees C b) 25 degrees C c) 40 degrees C d) 45 degrees C e) 55 degrees C
e
The temperature of the carbon dioxide leaving the extinguisher horn can be as low as a) 0 degrees C b) -5 degrees C c) -30 degrees C d) -60 degrees C e) -80 degrees C
e
