1987 Montreal Protocol on Substances that Deplete the Ozone Layer, as either adjusted and/or amended in London 1990, Copenhagen 1992, Vienna 1995, Montreal 1997, Beijing 1999
United Nations Environment Programme / 1987 / enter into force on 1 January 1989
International protocol to be implemented by all ratifying Parties.
Ozone depleting substances (ODS) are halogenated chemicals that are stable enough to persist as such in the lower atmosphere, but they migrate up to the stratosphere, where they participate in photochemical mechanisms that generate very reactive products which destroy the ozone layer. Stratospheric ozone has a very important role in protecting Earth from UV radiations.
Because of their stability and low toxicity chemicals that are ODS have been used on a large scale in many applications until they have been related to the damage of the ozone upper layer. In 1985 the Vienna Convention for the protection of the Ozone Layer has been agreed upon and was followed by the Montreal Protocol to it.
The purpose of the Protocol is to phase out and eventually eliminate specified groups of halogenated substances (chlorinated and/or brominated) that are ODS, in order to protect human health and the environment. The Montreal protocol has been either adjusted and/or amended in London 1990, Copenhagen 1992, Vienna 1995, Montreal 1997 and Beijing 1999.
The London 1990 amendments underline in the preamble the importance of promoting international co-operation in the research, development and transfer of alternative technologies relating to the control and reduction of emissions of ODS.
Article 9 of the Protocol states that Parties shall co-operate in promoting, directly or through competent international bodies, research, development and exchange of information on possible alternatives to ODS, to products containing such substances and to products manufactured with them.
Due to the importance of a broad international action that includes developing countries, special support measures are provided for them in article 5 of the Protocol and in article 10 of the London amendment, to ensure that ‘the best available, environmentally safe substitutes and related technologies are expeditiously transferred to Parties’ that are in this category.
By requesting the phase out and elimination of specified ODS the Montreal Protocol stimulated the search for substitute substances and technologies to these substances. All parties have to elaborate their strategies and plans to comply with the provisions, targets and timetables of the Protocol, while collaborating in finding and making generally available safer alternatives.
The London Amendment that entered into force on 10 August 1992
The Copenhagen Amendment that entered into force on 14 June 1994
The Montreal Amendment that entered into force on 10 November 1999
The Beijing Amendment that entered into force on 25 February 2002
The Kigali Amendment that entered into force on 1 January 2019
Last update: 18.11.2010