单项选择题
A.prevent the generation of flammable or combustible gas in tanks
B.blow out cargo lines to prevent the build up of gas concentrations
C.dilute tank atmospheres to keep gas concentrations below the lower explosive limit
D.prevent fires in the pumproom by continually displacing flammable vapors
单项选择题 An inert gas system installed on a tanker is designed to（）.
单项选择题 All ships（）suspected infectious disease on board should radio information to Port Health Officer.
单项选择题 After sending a message describing the symptoms of an ill crew member，you receive a message containing the code MRL. This means（）.