Annexes A to F and the Kigali Amendment: the protocol that protects the ozone layer

Background

The Montreal Protocol on Substances that Deplete the Ozone Layer was adopted on 16 September 1987. It is described by the United Nations Environment Programme as one of the rare treaties to have achieved universal ratification. The Protocol controls nearly 100 man-made ozone-depleting substances, listed in its Annexes: Annex A covers CFCs and halons, Annex B other fully halogenated CFCs along with carbon tetrachloride and methyl chloroform, Annex C hydrochlorofluorocarbons, Annex E methyl bromide and Annex F hydrofluorocarbons. The Kigali Amendment was agreed at the 28th Meeting of the Parties on 15 October 2016 in Kigali, Rwanda. It added hydrofluorocarbons, which are greenhouse gases rather than ozone-depleting substances, to the list of controlled substances, and set a timeline to cut them by 80 to 85 per cent by the late 2040s.