What is TRUE of pressure/vacuum valves?A.They are designed to provide for the flow of small volumes of tank atmospheres caused by thermal variations in a cargo tankB.They should operate in advance of the pressure/vacuum breakersC.They should be kept in good working order by regular inspection and cleaningD.All of the above
What is TRUE of pressure/vacuum valves?
A.They are designed to provide for the flow of small volumes of tank atmospheres caused by thermal variations in a cargo tank
B.They should operate in advance of the pressure/vacuum breakers
C.They should be kept in good working order by regular inspection and cleaning
D.All of the above
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