B2.1.7 The Montreal Protocol


The Montreal Protocol on Substances that Deplete the Ozone Layer became effective in 1989.

Controlled substances include:

  • CFCs (Chlorofluorocarbons)
  • Halons
  • Carbon tetrachloride
  • Methyl chloroform
  • HCFCs (Hydrochlorofluorocarbons)
  • HBFCs (Hydrobromofluorocarbons)
  • Methyl bromide


The Montreal Protocol contains provisions for regular review of the adequacy of control measures. This is based on assessments of evolving scientific, environmental, technical, and economic information.

Changes have been made to the requirements of the Protocol at subsequent meetings. Full details are available in the Montreal Protocol Handbook, which is available from United Nations Environment Programme: http://ozone.unep.org/