When a ship's low-pressure CO2 fixed fire extinguishing system is activated from a remote location, what determines the quantity of CO2 being released into a selected space?

Correct Answer: Option D — A pneumatic timer controls each discharge selector valve, and is preset for each space.

USCG regulations for low-pressure systems require a pneumatic timing device to govern the discharge duration and regulate the precise quantity of carbon dioxide delivered to the specific protected space.