A.you are entering a space containing poisonous vapors
B.you are entering a space containing explosive gases
C.the regulator of the breathing apparatus malfunctions
D.the face piece of the breathing device is too tight
您可能感興趣的試卷
你可能感興趣的試題
A.Crescent
B.Sheath-screw boom
C.Quadrantal
D.Radial
A.flow of petroleum through pipes
B.spraying or splashing of petroleum
C.settling of solids or water in petroleum
D.All of the above
A.pump out
B.to pump out
C.pumping out
D.be pumped out
A.prevent the passage of flammable gases
B.prevent the passage of poisonous vapors
C.delay the spread of heat and flames
D.maintain watertight integrity
A.Sheath-screw davits
B.Gravity davits
C.Radial davits
D.Quadrantal davits
最新試題
In nautical terminology a dog is a（）.
Limit switches are used on which davits?（）
As the propeller turns，voids are formed on the trailing and leading edges of the propeller blades causing a loss of propulsive efficiency，pitting of the blades，and vibration. These voids are known as（）.
The rudders are amidships and both screws are going ahead. What will happen if the starboard screw is stopped?（）
Centrifugal pumps have what advantage(s) over reciprocating pumps?（）.
Permission is kindly requested（）the ballast water.
An example of a messenger is a（）.
An integral part of a blowout preventer that serves as the closing element on an open hole，and whose ends do not fit around the drill pipe but seal against each other and shut off the space below completely is the（）.
Anchors are prevented from running out when secured by the（）.
The portable radio apparatus means（）.