🔍 Key Concepts

• Crude oil washing (COW) safety requirements in port • The role of an inert gas system in preventing tank explosions • Regulations on discharge of oily mixtures while alongside a dock

💭 Think About

• Ask yourself what the main explosion/fire hazard is when washing cargo tanks with crude oil and what system is specifically designed to control that hazard. • Consider which answer choice describes a required safety condition inside the tank itself during crude oil washing. • Think about MARPOL/US regulations on whether any oily water or mixtures can be discharged overboard while the vessel is in port or alongside a terminal.

✅ Before You Answer

• Identify which option directly addresses tank atmosphere safety during COW operations. • Eliminate any options that conflict with MARPOL Annex I or national rules on overboard discharge in port. • Verify which system must be in proper operation in each tank being washed to keep hydrocarbon vapors below the flammable range.