单项选择题
A.a hood or hard hat
B.a face mask or goggles
C.boots
D.chemical resistant gloves
单项选择题 On the all-purpose nozzle，the position of the valve when the handle is all the way forward is（）.
单项选择题 On a vessel carrying grades A，B，C or D cargoes，enclosed spaces where sources of vapor ignition are normally present shall NOT be segregated from cargo tanks by（）.
单项选择题 Oil may NOT be transferred unless（）.