will remove all the toxic fumes from the air
has the greatest cooling ability
will leave no harmful residue
completely removes combustible vapors from the air
第1题：
Foam is a very effective smothering agent and ______.
A.it provides cooling as a secondary effect
B.works well on extinguishing electrical fires
C.can be used to combat combustible metal fires
D.All of the above
第2题：
Alcohol foam
Dry chemical
Chemical foam
Water fog
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：
It is MOST effective on very hot oil fires where the temperatures of the liquid exceed 100°C (212°F)
Most foams can be used with dry chemicals to attack a fire by two methods
Foam is effective on combustible metal fires
Foam can be made with seawater or fresh water
第5题：
acrylic acid
benzene
oleum
vinyl toluene
第6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7题：
Dry chemicals
CO2
Foam
All the above
第8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9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
第10题：
alternate expansion and contraction as water in a liquid state becomes a vapor
absorption of smoke and gases as water is converted from a liquid to a vapor
rapid contraction as water is converted from a liquid to a vapor
rapid expansion as water absorbs heat and changes to steam