You should know the outage needed for the liquids you carry because:

Question

Accepted Answer

C: Some liquids expand more than others when they get warm.. Outage refers to the amount a fluid expands when it is heated. A cargo tank should never be completely filled because room needs to be reserved for the outage. Be aware of the amount of outage required for the liquid that you are transporting.

You should know the outage needed for the liquids you carry because:

Massachusetts CDL Tanker Test Info