🔍 Key Concepts

• Fixed CO₂ fire-extinguishing systems are common on ships for machinery spaces and cargo holds • CO₂ works mainly by displacing oxygen, not by cooling or smothering with foam • Think about what happens to people breathing in a space where oxygen has been pushed out

💭 Think About

• In an enclosed space, if large amounts of CO₂ are released, what happens to the concentration of oxygen in the air? • Which of the listed dangers directly relates to breathing and the human body’s need for oxygen? • Which options describe effects that are more typical of heat, chemicals, or physical contact, rather than a gas that simply replaces air?

✅ Before You Answer

• Verify which danger is specifically tied to lack of oxygen to the brain and body • Eliminate options that involve chemical reactions or heat damage, which are not how CO₂ systems normally harm people • Consider that the primary safety warning on CO₂ systems is about personnel not being inside the compartment when discharged and why that is.