1574. U.S. regulations require having a responsible person present at the hatches of spaces containing Class 1 explosive materials. When does the requirement apply during cargo operations?

U.S. regulations mandate a responsible person's presence whenever a hatch to a space containing Class 1 explosives is open, regardless of cargo handling activity. This requirement ensures continuous supervision, security, and emergency response capabilities, as outlined in 33 CFR Part 126, and is not limited to cargo handling or random checks.