Actuating the CO2 fixed system causes which...

🔍 Key Concepts

• Fixed CO2 fire extinguishing systems are designed to protect machinery spaces by flooding the area with CO2 to remove oxygen • Before CO2 is released, certain machinery and systems must be secured to prevent spreading fire or drawing CO2 out of the space • Understand the difference between mechanical ventilation (fans, blowers) and natural ventilation (openings, vents without fans)

💭 Think About

• When CO2 is released into an engine room, which system(s) could interfere with CO2 staying in the space and reduce its effectiveness? • Which items in the answer choices are normally interlocked or automatically shut down when a fixed CO2 system is activated on a vessel? • Think about what must be stopped FIRST during a machinery-space fire: air movement, fuel flow, or lighting?

✅ Before You Answer

• Identify which choice directly affects airflow driven by machinery (fans, blowers) rather than passive openings • Consider which systems are typically tied into automatic shutdown interlocks with fixed fire-extinguishing systems • Ask yourself: which shutdown is critical to keeping CO2 concentrated in the protected space during discharge?

Actuating the CO2 fixed system causes which of the following to shut down?

Fuel supply

Electrical lighting

Mechanical ventilation

Natural ventilation