Which component houses the carbon dioxide scrubber canister in the closed-circuit system?

• A. Breathing bag
• B. Oxygen cylinder
• C. Carbon dioxide scrubber canister
• D. Inhalation hose

Answer: (C)

In a closed-circuit rebreather, CO2 is removed by a scrubber material packed inside a dedicated container—the scrubber canister. This canister acts as the housing for the absorbent that chemically binds carbon dioxide from the exhaled gas before it’s rebreathed. The other parts have different roles: the breathing bag provides a gas reservoir for inhalation, the oxygen cylinder supplies fresh oxygen, and the inhalation hose carries gas to the mouth. So the component that houses the carbon dioxide scrubber is the scrubber canister itself, since that is the enclosure that contains the scrubber media responsible for CO2 removal.