conducts electricity
should be directed at the base of the fire
is most effective on burning gases which are flowing
extinguishes by cooling oil fires below ignition temperature
第1题：
An extinguishing agent which effectively cools, dilutes combustible vapors, removes oxygen, and provides a heat and smoke screen is ______.
A.carbon dioxide
B.Halon 1301
C.dry chemical
D.water fog
第2题：
Generally, the first action in extinguishing an LFG fire caused by escaping gas is to ______.
A.sweep flames away with water spray
B.shut off the leak
C.use a chemical foam fire extinguisher
D.call the local fire department
第3题：
One of the limitations of foam as an extinguishing agent is that foam ______.
A.cannot be made with salt water
B.is heavier than oil and sinks below its surface
C.is corrosive and a hazard to fire fighters
D.conducts electricity
第4题：
acrylic acid
benzene
oleum
vinyl toluene
第5题：
increases the size of foam bubbles formed
increases the rate of foam production
improves the extinguishing properties of foam
gives the nozzleman more freedom of movement，since it can be placed anywhere in the hose line
第6题：
As an extinguishing agent, foam ______.
A.conducts electricity
B.should be directed at the base of the fire
C.is most efffective on buring gases which are flowing
D.extinguishes by cooling oil fires below ignition temperature
第7题：
turning it upside down
pressing the foam lever
squeezing the grip handle
opening the hose valve
第8题：
______, as the chemical extinguisher agent, should be used for an electric fire.
A.dry chemical or foam
B.foam or soda acid
C.carbon dioxide or foam
D.carbon dioxide or dry chemical
第9题：
Alcohol foam
Dry chemical
Chemical foam
Water fog
第10题：
preventing oxygen from reaching the burning material
cooling the burning material below its ignition temperature
using the extinguishing agent to make the burning material fire-resistant
using the extinguishing agent to absorb the heat