The image below is a schematic flow diagram of a typical oil refinery that depicts the various unit processes and the flow of intermediate product streams that occurs between the inlet crude oil feedstock and the final end products.
In order to check-in into a hotel, the person must be 21 years old.  If the person is younger than 21, then a parent or guardian can  give permission for them to check-in. 1 person found this useful.
Guests are required to be 21 years of age (on embarkation day) to travel on their own. Guest ages will be verified at embarkation. Guests not conforming to this policy will result in denied boarding and no compensation will be provided at embarkation. Guests Under the Age of 21 MUST travel with a relative or guardian of 25 years of age or older. The guardian does not need to be a legal guardian.