Wet-Bath Simulator
Definition
Calibration accessory holding a 0.10 g per L aqueous ethanol solution at 34 degrees Celsius. The vapour above gives a known reference BrAC for daily breath-analyser calibration.
- Solution
- 0.10 g/L aqueous ethanol
- Bath temperature
- 34 degrees Celsius
- Function
- Produces a known reference vapour BrAC
- Use
- Daily breath-analyser calibration check
Common questions
Why is the wet-bath simulator held at 34 degrees Celsius specifically?+
That temperature approximates the partition ratio between alveolar breath and blood alcohol used in breath testing, so the headspace vapour above the solution reproduces the target BrAC the instrument is meant to read.
What happens if a breath analyser fails its wet-bath simulator check?+
The instrument is taken out of service or recalibrated before further use, and any evidentiary breath test results from a period surrounding a failed check can be challenged for reliability.
Related terms
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- IR Breath Analyser
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