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Vienna Convention – For the protection of the ozone layer

Last reviewed: ‎22‎ ‎January‎ ‎2025

The Vienna Convention is a global treaty primarily aimed at promoting international cooperation regarding depletion of the ozone layer.

The Vienna Convention for the Protection of the Ozone Layer, or the Ozone Convention, was signed in 1985 and entered into force in 1988. The convention states that all participating countries will take measures to protect human health and the environment from hazardous effects of modifications of the ozone layer. Sweden has ratified the convention including its protocols and amendments.

The goal of the Vienna Convention is that all parties will promote cooperation by means of systematic observations, research, and exchange of information on the effect of human activities on the ozone layer. Furthermore, the parties will adopt legislative or administrative measures against activities that may have negative effects on the ozone layer. Formal requirements to take specific actions were added in the Montreal protocol. 

The Montreal protocol on substances that deplete the ozone layer 

An important part of the Convention is the Montréal Protocol on Substances that Deplete the Ozone Layer. Entered into force in 1989, the protocol is a treaty on actions for phasing out the production, consumption, and emissions of the following ozone-depleting substances 

  • Chlorofluorocarbons, CFCs
  • Hydrochlorofluorocarbons, HCFCs
  • Bromofluorocarbons, BFCs
  • Carbon tetrachloride (CCl4)
  • Halons
  • Methyl bromide (CH3Br)
  • Bromochloromethane (CH2BrCl)
  • Methyl chloroform (C2H3Cl3)

The protocol has three assessment panels with technical/economic, scientific, and environmental perspectives. The findings of the protocol´s assessment panels have led to several revisions of the protocol. In total there are six amendments to the protocol: the London Amendment (1990), the Copenhagen Amendment (1992), the Vienna Amendment (1995), the Montreal Amendment (1997), the Beijing Amendment (1999) and the Kigali Amendment (2019). 

In the Kigali Amendment, which was agreed in Kigali, Rwanda in 2016, the Parties of the Montreal protocol adopted a step-by-step reduction of the production and consumption of hydrofluorocarbons, HFCs, which are potent greenhouse gases. The Kigali Amendment entered into force on 1 January 2019. 

Decision procedure in the Convention and the Protocol 

All decisions are made by the Parties to the convention and protocol, either at the Conference of the Parties (for convention issues) or at the Meeting of the Parties (for protocol issues). The decisions are taken by consensus by each country’s government representatives. The reports prepared by the Technology and Economic Assessment Panel (TEAP) on possible technical solutions and alternatives to ozone-depleting substances and HFCs serve as a basis for decision-making by the Parties. Once decisions are taken by the Parties, the Parties are bound to implement these decisions in their respective countries.

Facts on the ozone layer 

The natural ozone layer is found at an altitude of 10-50 kilometres, in the part of the atmosphere called the stratosphere. It absorbs ultraviolet light (UV-B radiation) from the sun. This radiation is harmful to living organisms and the ozone layer serves as a protecting shield for life on earth. Emissions of chlorofluorocarbons, “freons”, and similar substances have depleted the layer, enabling more harmful radiation to reach the earth. Therefore, these emissions must be reduced or eliminated. 

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