What is the purpose of inerting during tank transfers?

• A. To cool cargo.
• B. To reduce fire or explosion risk by displacing oxygen.
• C. To increase tank pressure.
• D. To remove water from tank.

Answer: (B)

Inerting during tank transfers is about creating an atmosphere inside the tank that won’t support ignition by removing most of the oxygen. By flushing the tank with an inert gas (like nitrogen) and displacing the air, the oxygen concentration falls below the flammable limits of the cargo vapors. With less oxygen available, even a spark or hot surface is unlikely to ignite the vapors, so the fire or explosion risk during transfer is greatly reduced.

This isn’t about cooling the cargo, increasing tank pressure, or removing water. Those actions don’t address the ignition risk posed by flammable vapors in air, which is why inerting specifically targets displacement of oxygen to keep the atmosphere nonflammable.