更多"Compared to the amount of concentra"的相关试题:
[单项选择]Firefighting foam is only effective when the foam（）.
A. penetrates to the bottom of the fire
B. is kept saturated with low-velocity water fog
C. mixes with the burning fuel oil
D. completely covers the top of the burning liquid
[单项选择]What type of liquid is used in the liquid P/V breaker（）.
A. Hydraulic oil
B. Water-antifreeze mixture
C. Distilled water
D. Oil from the cargo
[单项选择]Concentrated heavy loads are involved in loading a LASH vessel. What does NOT require close attention due to such loads while working cargo?（） .
A. GM - available and required
B. Longitudinal stress numeral
C. Tons per inch immersion numeral
D. Draft
[单项选择]If the weights are concentrated in the middle part，then（）will happen on board the ship.
A. hogging
B. stiffness
C. sagging
D. listing
[单项选择]Portable foam type fire extinguishers are most effective on（）.
A. mattress fires
B. oil fires
C. wood fires
D. All of the above
[单项选择]Foam extinguishes a fire by（）.
A. shutting off the air supply
B. cooling the fuel to below ignition temperature
C. dispersing the fuel
D. removing the source of ignition
[单项选择]Where foam extinguishing systems are provided on a ship，each machinery flat in the protected space must have a(n)（）.
A. coaming
B. alarm
C. drain
D. fire sensor
[单项选择]Foam-type portable fire extinguishers are more usefull in combating fires involving（）.
A. solid materials such as wood or bales of fiber
B. inflammable liquids
C. electrical equipment
D. metallic solids
[单项选择]Deck foam systems，designed to protect cargo areas on tankers built after January 1，1975，must have a supply of foam-producing material to operate the system at its designed rate of foam production for（）.
A. 15 minutes without recharging
B. 20 minutes without recharging
C. 25 minutes without recharging
D. 30 minutes without recharging
[单项选择]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
[单项选择]Foam-type portable fire extinguishers are most useful in combating fires involving（）.
A. solid materials such as wood or bales of fiber
B. inflammable liquids
C. electrical equipment
D. metallic solids
[单项选择]Foam extinguishes a fire mainly by（）.
A. cooling
B. chemical action
C. smothering
D. inerting the air
[单项选择]As an extinguishing agent,foam（）.
A. couducts electricity
B. should be directed at the base of the fire
C. is most effective on burning gases which are flowing
D. extinguishes by cooling oil fires blow ignition temperature
[单项选择]A portable foam fire extinguisher is placed in operation by（）
A. turning it upside down
B. pressing the foam lever
C. squeezing the grip handle
D. opening the hose valve
