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Ozone Unit — MECENR
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The problem — gases that destroy ozone

How CFCs, HCFCs, and other gases damaged the ozone layer — and why Seychelles, as an Article 5 country, treats their control as a priority.

The problem — gases that destroy ozone#

In 1974, scientists Mario Molina and Frank Sherwood Rowland warned that chlorofluorocarbons (CFCs) — common refrigerants and aerosol propellants — were drifting into the stratosphere and destroying ozone molecules in chain reactions. Each chlorine atom from a CFC could destroy 100,000 ozone molecules before being deactivated.

Source: UNEP OzonAction — About the Montreal Protocol. Their 1974 paper led to the 1995 Nobel Prize in Chemistry.

The "ozone hole"#

By the mid-1980s scientific surveys over Antarctica revealed a seasonal ozone hole — an area where ozone concentrations dropped to half their historical levels each spring. The world responded with the Vienna Convention (1985) and then the Montreal Protocol (1987) — a binding treaty to phase out the gases that caused it.

Source: UNEP Ozone Secretariat — Montreal Protocol.

The substances#

The Montreal Protocol regulates entire families of substances:

  • CFCs (Annex A Group I) — first-generation refrigerants such as R-11, R-12. Banned globally.
  • Halons (Annex A Group II) — fire-suppression agents. Banned globally.
  • Carbon tetrachloride and methyl chloroform (Annex B) — solvents. Banned globally.
  • HCFCs (Annex C) — second-generation refrigerants such as R-22. In Seychelles, sale, use, and decommissioning are permit-only under regs 5–7 of S.I. 24/2000.
  • HBFCs, methyl bromide, and (under Kigali) HFCs — see Today and Tomorrow.

Source: Environment Protection (Ozone) Regulations 2000 — Schedule.

Why Seychelles cares#

A degraded ozone layer raises ground-level UV — increasing skin cancers and cataracts in people, harming reef-building corals and marine plankton, and reducing crop yields. For an island nation that depends on tourism, fisheries, and food imports, all three vectors matter.

The legal basis for Seychelles' response sits at section 10(3) of the Environment Protection Act 2001, which empowers the Minister to make regulations controlling substances that endanger the stratosphere — the authority the Environment Protection (Ozone) Regulations 2000 were issued under.

What's next#