Comments on the paper entitled ?Concentration dependency of the BAC/BrAC (blood alcohol concentration/breath alcohol concentration) conversion factor during the linear elimination phase? by H.-T. Haffner et al.

A study concerning the blood/breath alcohol conversion factor Q: Concentration dependency and its applicability in daily routine

“…The point that cannot be adapted with a single factor is the fact that in Austria the lower of both BrAC measurement values is taken as ''relevant result''. In this connection it was asked if the calculations leading to the hyperbolic function were valid for Germany only [33]. This question can be negated now if our results are taken.…”

Concentration units used to report blood‐ and breath‐alcohol concentration for legal purposes differ between countries which is important to consider when blood/breath ratios of alcohol are compared and contrasted

“…This could lead to problems when publications from a particular country are introduced into evidence, such as when alcohol‐related crimes are prosecuted. Whether BAC is reported as m/m as opposed to m/v units is also important to consider when BBRs of ethanol are compared and contrasted between countries [43, 44].…”

“…Forensic BAC results reported in studies from Germany should not be directly compared with other countries without taking into consideration that ethanol was analyzed in serum and BAC calculated using a factor of 1.236. This becomes important, for example, when BBRs of alcohol are calculated and compared between countries [43, 44]. BBRs reported in controlled drinking experiments from Germany are significantly lower than values reported in international publications by about 10% on average.…”