1.3 Montreal Protocol and International Agreements

1.3 Montreal Protocol and International Agreements

Understanding the international framework behind refrigerant regulations helps explain why EPA rules exist and where they are heading. The Montreal Protocol is the most successful environmental treaty in history — and it directly shapes the regulations tested on the EPA 608 exam.

The Ozone Layer and Why It Matters

The ozone layer is a concentration of ozone (O3) molecules in the stratosphere, approximately 10-30 miles above Earth's surface. It serves as Earth's natural sunscreen, absorbing 97-99% of the sun's harmful ultraviolet-B (UV-B) radiation.

When the ozone layer is depleted:

• Increased UV-B radiation reaches Earth's surface
• Higher rates of skin cancer, cataracts, and immune system suppression in humans
• Damage to marine ecosystems, particularly phytoplankton
• Reduced crop yields in agriculture
• Degradation of outdoor materials (plastics, rubber, wood)

How Refrigerants Destroy Ozone

Chlorine is the primary ozone-destroying element in refrigerants. Here is how the process works:

1. CFC and HCFC molecules released at ground level are extremely stable
2. They rise through the troposphere into the stratosphere (takes 2-5 years)
3. Intense UV radiation breaks the molecules apart, releasing chlorine atoms
4. A single chlorine atom can destroy 100,000 ozone molecules before becoming inactive
5. This catalytic cycle continues for decades in the stratosphere

For the Exam: Chlorine is the element in CFCs and HCFCs that destroys ozone. A single chlorine atom can destroy up to 100,000 ozone molecules. HFCs do NOT contain chlorine and have zero ODP.

The Montreal Protocol (1987)

The Montreal Protocol on Substances that Deplete the Ozone Layer was adopted in 1987 and has been ratified by 198 countries — making it the first and only UN treaty to achieve universal ratification. Key provisions:

The Kigali Amendment (2016)

While the Montreal Protocol addressed ozone-depleting substances, the HFCs that replaced them turned out to be potent greenhouse gases. The Kigali Amendment, adopted in 2016 in Kigali, Rwanda, extended the Montreal Protocol to include an HFC phasedown:

• Developed countries began reducing HFC consumption in 2019
• Most developing countries will freeze consumption in 2024
• Global HFC consumption will be reduced by more than 80% over 30 years
• The U.S. ratified the Kigali Amendment in 2022

U.S. Implementation: The AIM Act (2020)

The American Innovation and Manufacturing (AIM) Act was signed into law in December 2020. It is the domestic legislation that implements the Kigali Amendment's HFC phasedown in the United States.

The AIM Act gives EPA authority to:

1. Phase down HFC production and consumption by 85% from baseline by 2036
2. Manage HFCs through technology transitions (sector-specific GWP limits)
3. Facilitate the transition to next-generation technologies

Key International Takeaways for the Exam

• The Montreal Protocol addressed ozone-depleting substances (CFCs, HCFCs)
• The Kigali Amendment extended the protocol to address climate-warming HFCs
• The AIM Act is the U.S. law implementing the HFC phasedown
• CFCs have been completely phased out in the U.S. since 1996
• HCFCs are being phased out with a complete ban by 2030
• HFCs are being phased down (not out) by 85% by 2036