Fuel cell oxygen analyser — FRCA Primary MCQ

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ModeratePhysics and Clinical MeasurementFuel cell oxygen analyserFRCA Primary

An anaesthetic machine oxygen analyser gradually drifts and has a slow response during checks. The sensor is replaced because it is consumable. Which analyser type is most likely?

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Correct answer: A — Galvanic fuel cell

A galvanic fuel cell consumes oxygen during an electrochemical reaction and has a finite life with a relatively slow response. Paramagnetic analysers are faster and exploit oxygen's magnetic properties. Infrared analysis is used for CO2 and volatile agents rather than oxygen. Consumable oxygen sensors require regular calibration and replacement.

Reference: Dorsch and Dorsch Understanding Anesthesia Equipment; RCoA Primary FRCA Syllabus