"With effect from 1 February 2012, the Storting Implementation of the national action plan introduced ‘drug driving limits’ for 20 narcotic substances and potentially intoxicating medicinal drugs. Norway thereby became the first country in the world to set legal and sentencing limits for substances other than alcohol. The amendments to the Road Traffic Act entered
into force on 22 July 2012. Among other things, the amendments are intended to ensure greater agreement between the Road Traffic Act’s provisions on drink driving and the regulation of driving under the influence of other intoxicating or narcotic substances."
[Note: The Storting is the Norwegian Parliament.]

Source

Norwegian Institute for Alcohol and Drug Research, "The Drug Situation in Norway 2012: annual report to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA)," (Oslo, Norway: December 2012), p. 6.
http://www.emcdda.europa.eu/s…