Cargo pump rooms on tank vessels, constructed in 1965, handling grade C liquid cargo shall have power ventilation systems. What is time requirement for these ventilation systems to completely change the air?

Correct Answer: Option B — 3 minutes

Title 46 CFR regulations govern tank vessel safety, specifically requiring power ventilation systems in cargo pump rooms handling volatile Grade C or higher liquid cargoes to achieve a complete air change every three minutes to prevent hazardous vapor accumulations.