The Montreal Protocol is the unofficial name for The Montreal Protocol on Substances that Deplete the Ozone Layer. Adopted September 16, 1987 after a series of rigorous negotiations between member countries of the United Nations, the Montreal Protocols outlines the systematic reduction of the production of substances known to deplete ozone in the upper atmosphere.

The protocol didn't reach it's full power until 29 countries and the EEC (representing 82% of the world) ratified the protocols on January 1, 1989. The United Nations Environment Programme drafted the Montreal Protocols in such a way to allow changes based on newly acquired scientific knowledge without a long process of re-ratification.

Since 1990, the protocols have gone through five phases of adjustments or amendments:

The Montreal Protocol defines a "controlled substance" as any substance that will react chemically in such a way with ozone as to cause ozone to become something other than ozone. These substances are controlled "whether existing alone or in a mixture" (as well as "the isomers of any such substance") which exists in "a manufactured product other than a container used for the trasnportation or storage of the substance." The Montreal Protocol introduced control measures for the following substances:

The following is an example of the timetable for decreased production and consumption levels of CFCs:

  • July 23, 1991 - December 1992: Not to exceed 150% of the rate in 1986.
  • January 1994 - December 1995: Not to exceed 25% of the rate in 1986.
  • January 1996 - December 2002: Not to exceed 0% of the rate between 1995-7.
  • January 2003 - December 2004: Not to exceed 80% of the rate of 1995-7.
  • January 2005 - December 2006: Not to exceed 50% of the rate in 1995-7.
  • January 2007 - December 2009: Not to exceed 15% of the rate in 1995-7.
  • After January 2010: Not to exceed zero.

Essentially, countries who have agreed to the terms of the Montreal Protocol will be able to once again produce CFCs starting January 1, 2003.

Article 5 of the Montreal Protocol outlines special situations for developing countries. The protocol allows countries that produce very small levels of controlled substances to keep doing so for ten years (until January 1, 1999).

Article 6 outlines how the countries involved in the agreement must report their national data regarding the depletion of the controlled substances.

Article 8 explains that any country that does not comply with the agreements and violates the levels of production of consumption will be immediately denoted "non-compliant" and are no longer applicable for the benefits of the fund mechanism.