The Convention was adopted by the Senior Advisers to the Economic Commission for Europe Governments on Environmental and Water Problems at their Resumed Fifth Session held at Helsinki from 17 to 18 March 1992. The adoption on 17 March 1992 was through resolution E/ECE/1268. The Convention was adopted immediately following the adoption of the Convention on the Protection and Use of Transboundary Watercourses and International Lakes. The Convention was opened for signature at Helsinki from 17 to 18 March 1992 and was open for signature at United Nations Headquarters in New York until 18 September 1992.
On 18 March 1992, the following 26 countries, together with the European Community, signed the Convention: Albania; Austria; Belgium; Bulgaria; Canada; Denmark; Estonia; Finland; France; Germany; Greece; Hungary; Italy; Latvia; Lithuania; the Netherlands; Poland; the Russian Federation; Spain; Sweden; Switzerland; the United Kingdom of Great Britain and Northern Ireland; and the United States of America. Luxembourg, Norway and Portugal signed later in 1992.