单项选择题
A.spray directly on the base of the fire B.flow the foam down a nearby vertical surface C.sweep the fire with the foam D.spray directly on the surface of the fire
The atmosphere in a tank is too lean if it is（）.A.incap...
单项选择题The atmosphere in a tank is too lean if it is（）.
A.incapable of supporting combustion because the hydrocarbon content is below the LFL (Lower Flammable Limit) B.capable of supporting combustion because the hydrocarbon content is above the UFL (Upper Flammable Limit) C.capable of supporting a fire once started D.not safe for ballasting
The all-purpose nozzle will produce a fog spray when yo...
单项选择题The all-purpose nozzle will produce a fog spray when you（）.
A.pull the nozzle handle all the way back toward the operator B.pull the nozzle handle back to a position where the handle is perpendicular to the plane of the nozzle C.push the nozzle handle forward as far as it will go D.insert a fog applicator between the fire hose and nozzle
Small quantities of flammable liquids needed at a work ...
单项选择题Small quantities of flammable liquids needed at a work site should be（）.
A.used only under the supervision and direction of a ship's officer B.tightly capped and stowed with other tools near the job site when securing at the end of the day C.used only when a pressurized fire hose is laid out ready for immediate use D.in a metal container with a tight cap
