The Montreal Protocol: Phasing Out Ozone-Depleting Substances to Protect the Ozone Layer

Core Purpose

Protect the stratospheric ozone layer, which absorbs harmful UV radiation.

Mechanism

Phase out production/consumption of ozone-depleting substances (ODS): CFCs, HCFCs, halons (used in refrigeration, AC, fire extinguishers, aerosols).

Achievements

• Near-universal ratification (1987).
• Significant ODS reduction; ozone layer recovering.
• Prevented millions of skin cancer/cataract cases.
• Co-benefit: many ODS are potent greenhouse gases, so climate mitigation too.
• Spurred development of safer alternatives.

The Montreal Protocol is a landmark success in global environmental cooperation.