IR Wavelength Range — FRCA Primary MCQ
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Correct answer: B — 700 nm - 1 mm (infrared)
Infrared radiation spans approximately 700 nm to 1 mm wavelength. CO2 absorbs specifically at 4.26 μm and N2O at 4.5 μm (both in the mid-infrared range). Volatile agents absorb at approximately 3.3 μm. Water vapour also absorbs IR and can interfere with measurements requiring sample drying or compensation in some analysers.
Reference: Al-Shaikh Stacey 2019 Essentials of Anaesthetic Equipment