单项选择题
A.Fires in electrical equipment B.Flammable oils and greases C.Class A fires in ordinary combustibles D.Materials containing their own oxygen
Halon extinguishes fire primarily by（）.A.coolingB.smoth...
单项选择题Halon extinguishes fire primarily by（）.
A.cooling B.smothering C.shielding of radiant heat D.breaking the chain reaction
Halon extinguishes a fire by（）.A.breaking the chain rea...
单项选择题Halon extinguishes a fire by（）.
A.breaking the chain reaction B.smothering the fire C.cooling the fire D.coating the fuel with a nonflammable surface
Halon extinguishers used on a class C fire should be di...
单项选择题Halon extinguishers used on a class C fire should be directed at the（）.
A.base of the equipment B.top of the equipment C.power source D.source of the fire
