🔍 Key Concepts

• Fixed CO2 fire-extinguishing systems on ships and how they are activated • The purpose of a discharge alarm siren (to warn personnel to evacuate before CO2 is released) • Difference between alarms powered by ship’s electrical systems and alarms activated by the flow of extinguishing agent

💭 Think About

• Ask yourself: If the ship loses all electrical power, should the CO2 discharge alarm still be able to warn people? Why or why not? • Think about when the alarm must sound: is it before, during, or only after CO2 starts to move through the pipes? How does that timing affect the power source? • Consider whether it is safer for this alarm to depend on a specific electrical bus, or on a physical condition directly linked to the release of CO2.

✅ Before You Answer

• Check how SOLAS and USCG treat the reliability of fire-extinguishing alarms – should they work even if normal power is lost? • Verify whether typical CO2 system discharge alarms are described as pneumatic/mechanical devices or as purely electrical sirens. • Confirm which of the choices directly depends on CO2 flow itself rather than shipboard electrical distribution.