× Information on this section of ECOLEX comes from the InforMEA Portal which compiled information from MEA Secretariats with the support of the European Union. The accuracy of the information displayed is the responsibility of the originating data source. In case of discrepancy the information as displayed on the respective MEA website prevails. Decision VC XI/4: Twelfth meeting of the Conference of the Parties to the Vienna Convention for the Protection of the Ozone Layer Document type Decision Reference number XI/4 Date Nov 24, 2017 SourceUNEP, InforMEA Status Active Subject Waste & hazardous substances, Air & atmosphere Treaty Vienna Convention for the Protection of the Ozone Layer (Mar 22, 1985) Meeting Eleventh Conference of the Parties Website ozone.unep.org Abstract To convene the twelfth meeting of the Conference of the Parties to the Vienna Convention for the Protection of the Ozone Layer back to back with the Thirty-Second Meeting of the Parties to the Montreal Protocol on Substances that Deplete the Ozone Layer.