The Montreal Protocol on Substances that Deplete the Ozone Layer

The Montreal Protocol on Substances that Deplete the Ozone Layer is a global agreement to protect the Earth’s ozone layer by phasing out the chemicals that deplete it. This phase-out plan includes both the production and consumption of ozone-depleting substances. The landmark agreement was signed in 1987 and entered into force in 1989.

The parties to the Protocol meet once a year to make decisions aimed at ensuring the successful implementation of the agreement. These include adjusting or amending the Protocol, which has been done six times since its creation. The most recent amendment, the Kigali Amendment, called for the phase-down of hydrofluorocarbons (HFCs) in 2016. These HFCs were used as replacements for a batch of ozone-depleting substances eliminated by the original Montreal Protocol. Although they do not deplete the ozone layer, they are known to be powerful greenhouse gases and, thus, contributors to climate change.

The Montreal Protocol provided a set of practical, actionable tasks that were universally agreed on. The Protocol has successfully met its objectives thus far and continues to safeguard the ozone layer today. Thanks to the collaborative effort of nations around the world, the ozone layer is well on its way to recovery.

Decision I/12A: Clarification of terms and definitions: Controlled substances (in bulk)

The First Meeting of the Parties decided in Dec. I/12A to agree to the following clarification of the definition of controlled substances (in bulk) in Article 1, paragraph 4 of the Montreal Protocol:

  1. Article 1 of the Montreal Protocol excludes from consideration as a “controlled substance” any listed substance, whether alone or in a mixture, which is in a manufactured product other than a container used for transportation or storage;
  2. any amount of a controlled substance or a mixture of controlled substances which is not part of a use system containing the substance is a controlled substance for the purpose of the Protocol (i.e. a bulk chemical);
  3. if a substance or mixture must first be transferred from a bulk container to another container, vessel or piece of equipment in order to realize its intended use, the first container is in fact utilized only for storage and/or transport, and the substance or mixture so packaged is covered by Article 1, paragraph 4 of the Protocol;
  4. if, on the other hand, the mere dispensing of the product from a container constitutes the intended use of the substance, then that container is itself part of a use system and the substance contained in it is therefore excluded from the definition;
  5. examples of use systems to be considered as products for the purposes of Article 1, paragraph 4 are inter alia:
    1. an aerosol can;
    2. a refrigerator or refrigerating plant, air conditioner or air-conditioning plant, heat pump, etc;
    3. a polyurethane prepolymer or any foam containing, or manufactured with, a controlled substance;
    4. a fire extinguisher (wheel or hand-operated) or an installed container incorporating a release device (automatic or hand-operated);
  6. bulk containers for shipment of controlled substances and mixtures containing controlled substances to users include (numbers being illustrative), inter alia:
    1. tanks installed on board ships;
    2. rail tank cars (10-40 metric tons);
    3. road tankers (up to 20 metric tons);
    4. cylinders from 0.4 kg to one metric ton;
    5. drums (5-300 kg);
  7. because containers of all sizes are used for either bulk or manufactured products, distinguishing on the basis of size is not consistent with the definition in the Protocol. Similarly, since containers for bulk or manufactured products can be designed to be rechargeable or not rechargeable, rechargeability is not sufficient for a consistent definition;
  8. if the purpose of the container is used as the distinguishing characteristic as in the Protocol definition, such CFC or halon-containing products as aerosol spray cans and fire extinguishers, whether of the portable or flooding type, would therefore be excluded, because it is the mere release from such containers which constitute the intended use.