单项选择题
A.break glass，pull valve，break glass，pull cylinder control B.sound evacuation alarm，pull handle C.open bypass valve，break glass，pull handle D.open stop valve，open control valve，trip alarm
The bypass valve on a self-contained breathing device s...
单项选择题The bypass valve on a self-contained breathing device should be opened if（）.
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
The boat is stowed on the davit rather than on a cradle...
单项选择题The boat is stowed on the davit rather than on a cradle with which type of davit?（）
A.Crescent B.Sheath-screw boom C.Quadrantal D.Radial
Static electricity may be built up by the（）.A.flow of p...
单项选择题Static electricity may be built up by the（）.
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
