UN Transport Agreements and Conventions: ADR (map of contracting parties)
Update 16.02.2018
15.01.2018: San Marino acceded to the European Agreement concerning the International Carriage of Dangerous Goods by Road (ADR)
European Agreement concerning the International Carriage of Dangerous Goods by Road (ADR), of 30 September 1957
50 Contracting Parties (16.02.2018):
Albania, Andorra, Austria, Azerbaijan, Belarus, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Georgia, Germany, Greece, Hungary, Iceland, Ireland, Italy, Kazakhstan, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Montenegro, Morocco, Netherlands, Norway, Poland, Portugal, Republic of Moldova, Romania, Russian Federation, San Marino, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Tajikistan, the former Yugoslav Republic of Macedonia, Tunisia, Turkey, Ukraine, United Kingdom of Great Britain and Northern Ireland.
See UNECE:
http://www.unece.org/trans/maps/un-transport-agreements-and-conventions-53.html