| U.S. regulations require a responsible person to be present at all times when the hatches of spaces containing Class 1 explosive materials are open. When is the responsible person released from the duty of attendance? |
| A) when the final paperwork has been completed for the Class 1 Explosives in the hold |
| B) when all cargo operations have been completed and the vessel is ready to depart |
| C) when the responsible person has been relieved by another officer |
| D) when the hatches for the hold containing Class 1 Explosives have been secured |
