Why is it essential to introduce CO2 from a fixed fire extinguishing system, into a large engine room, as quickly as possible?

Correct Answer: Option D — Updraft from the fire tends to carry the CO2 away.

Severe machinery space fires generate powerful thermal updrafts capable of lofting lighter-than-air combustion gases and heated air. Rapid injection of CO2 is critical to overcome these convective currents and achieve required design concentration before gases are vented.