In most industrial countries if a driver loses his driving license as a result of drug or alcohol offense he has to prove abstinence for several months up to one year.
The exact conditions of drug testing in urine or hair are different from country to country and depend on the individual situation.
In Germany the requirements of drug or alcohol testing have been stated in "The Assessment Criteria of Fitness to Drive of 2009" (Beurteilungskriterien für die Fahreignungsdiagnostik von 2009). The drugs to be tested in urine or hair are listed under MPA Tests. The chain of custody and the exact requirements of laboratory analyses have been specified in these guidelines. The laboratory must have a forensic accreditation according to DIN EN ISO/IEC 17025:2005. Having approved forensic toxicologists and years of experience the Laboratory Krone is accredited additionally for the interpretation of the results. Urine has to be collected under supervision (see details). The collection of samples must be performed by trained personal. The laboratory analyses are done in the context of a Medical Psychological Assessment (MPA).