[Does the 3d decimal number of single values have significance for calculating average blood alcohol content?]

Judgement of driving capability bases on determination of alcohol concentration in blood. This is carried out by two different methods, whereby the mean value is taken out of four test results. The mean value may very slightly taking either two or three decimal places. We suggest not to abandon the third decimal place. Due to German jurisdiction absolute incapability to drive is given when alcohol concentration in blood reaches 1.3 g Promille. An example shows that in a forensic case the limit of 1.3 g Promille was not reached if only two instead of three decimal places were taken.