Breath analysisFlanders
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251. Breath analysis
A breath analysis is a precise measurement of the alcohol concentration in a person’s exhaled breath. Unlike a preliminary breath test, which is mainly used for screening, a breath analysis is performed with an approved evidential device and produces a measured result that can be used for enforcement. The result is commonly expressed in milligrams of alcohol per litre of exhaled breath, although procedures and legal thresholds vary between countries.
What is a breath analysis in Belgium?
A Belgian breath analysis is performed with an approved device that measures the exact concentration of alcohol in the exhaled alveolar air.
When is a breath analysis performed in Belgium?
For ordinary drivers, a breath analysis is performed when the preliminary breath test indicates at least 0.22 mg/l. For drivers subject to the stricter professional limit, the threshold is 0.09 mg/l. Police may also require a breath analysis without first performing a breath test.
What alcohol concentration is punishable for ordinary drivers in Belgium?
An ordinary driver is punishable when the breath analysis measures at least 0.22 mg/l of alcohol in exhaled alveolar air, corresponding to approximately 0.5‰ in the blood.

Traffic rules
Flanders