To effectively enforce blood alcohol limits, the police should carry out highly visible random breath testing actions, in which all cars on a given stretch of road are stopped and their drivers tested regardless if there is a suspicion or not. This type of testing should be carried out preferably, but not only, at times and places where drunk drivers are likely to be found, e.g. on Friday and Saturday nights near discotheques.
According to the EC Recommendation, random breath testing with an alcohol screening device should be the "leading principle for surveillance of drink driving".
ETSC experts recommend a testing frequency of at least 1 test per 16 inhabitants (the current EU average) in every EU Member State. The benefits of applying random breath testing at this frequency across the EU exceed the cost by a factor of at least 36 (ETSC, 2003).
It is important that every detected offence is properly followed up and that sanctions are appropriate and dissuasive.