Circle System Soda Lime — FRCA Primary MCQ

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EasyPhysics & Clinical MeasurementCircle System Soda LimeFRCA Primary

In a circle system which component removes CO2?

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Correct answer: B — Soda lime canister

Soda lime removes CO2 from exhaled gas. The exothermic reaction produces water and calcium carbonate. Colour indicators (e.g. ethyl violet) change when the absorbent is exhausted. Unidirectional valves prevent retrograde flow but do not absorb CO2.

Reference: Al-Shaikh Stacey 2019 Essentials of Anaesthetic Equipment