Montreal Protocol

The Montreal Protocol on Substances that Deplete the Ozone Layer was signed on September 16, 1987, in Montreal, Canada. As of January 2021, 196 countries and the European Union were parties to the Montreal Protocol.

Initially, the treaty provided for freezing and phasing out of five most commonly used chlorofluorocarbons (CFCs) and halons and limiting export and import of ozone-depleting substances (ODSs).

Later amendments extended the protocol to other CFCs, hydrochlorofluorocarbons (HCFCs), ODSs, and even substances that do not deplete the ozone layer but feature considerable global warming potential, hydrofluorocarbons (HFCs).

Article 5.1 of the Montreal Protocol stipulates that the Parties to the Protocol approve the destruction technology. After the 30th Meeting of the Parties (November 5–9, 2018, Quito, Ecuador), the following list of destruction technologies for controlled substances was adopted: click for PDF.

Technology	Applicability
	Concentrated Sources									Dilute Sources
	Annex A		Annex B			Annex C	Annex E	Annex F			Annex F
	Group 1	Group 2	Group 1	Group 2	Group 3	Group 1	Group 1	Group 1	Group 2		Group 1
	Primary CFCs	Halons	Other CFCs	Carbon Tetrachloride	Methyl Chloroform	HCFCs	Methyl Bromide	HFCs	HFC-23	ODSs	HFCs
DRE*	99.99%	99.99%	99.99%	99.99%	99.99%	99.99%	99.99%	99.99%	99.99%	95%	95%
Cement Kilns	Approved	Not approved	Approved	Approved	Approved	Approved	Not determined	Approved	Not determined
Gaseous/Fume Oxidation	Approved	Not determined	Approved	Approved	Approved	Approved	Not determined	Approved	Approved
Liquid Injection Incineration	Approved	Approved	Approved	Approved	Approved	Approved	Not determined	Approved	Approved
Municipal Solid Waste Incineration										Approved	Approved
Porous Thermal Reactor	Approved	Not determined	Approved	Approved	Approved	Approved	Not determined	Approved	Not determined
Reactor Crackin	Approved	Not approved	Approved	Approved	Approved	Approved	Not approved	Approved	Approved
Rotary Kiln Incineration	Approved	Approved	Approved	Approved	Approved	Approved	Not determined	Approved	Approved	Approved	Approved
Rotary Kiln Incineration	Approved	Approved	Approved	Approved	Approved	Approved	Not determined	Approved	Approved
Inductively Coupled Radio Frequency Plasma	Approved	Approved	Approved	Approved	Approved	Approved	Not determined	Not determined	Not determined
Microwave Plasma	Approved	Not determined	Approved	Approved	Approved	Approved	Not determined	Not determined	Not determined
Nitrogen Plasma Arc	Approved	Not determined	Approved	Approved	Approved	Approved	Not determined	Approved	Approved
Portable Plasma Arc	Approved	Not determined	Approved	Approved	Approved	Approved	Not determined	Approved	Not determined
Chemical Reaction with H₂ and CO₂	Approved	Approved	Approved	Approved	Approved	Approved	Not determined	Approved	Approved
Gas Phase Catalytic Dehalogenation	Approved	Not determined	Approved	Approved	Approved	Approved	Not determined	Approved	Not determined
Superheated Steam Reactor	Approved	Not determined	Approved	Approved	Approved	Approved	Not determined	Approved	Approved
Thermal Reaction with Methane	Approved	Approved	Approved	Approved	Approved	Approved	Not determined	Not determined	Not determined
Thermal Decay of Methyl Bromide	Not determined	Not determined	Not determined	Not determined	Not determined	Not determined	Approved	Not determined	Not determined

* — Destruction & Removal Efficiency