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Why do HFC refrigerants have an ozone depletion potential of zero?

HFCs contain no chlorine, so their ODP is zero.

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  1. They do not contain chlorine ✔
  2. They break down before reaching the stratosphere
  3. They are heavier than air and stay near the ground

Why: HFCs were developed as replacements for ozone-depleting substances. Without chlorine or bromine, they do not attack the ozone layer. But some HFCs are strong greenhouse gases, which is a different problem.

Huh, didn't know that: EPA says ozone-depleting substances released at the surface can take two to five years to reach the stratosphere.

The dad joke
What did zero say to the number eight? Nice belt.
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References

Answer: They do not contain chlorine. HFCs were developed as replacements for ozone-depleting substances. Without chlorine or bromine, they do not attack the ozone layer. But some HFCs are strong greenhouse gases, which is a different problem.

  1. Ozone-Depleting Substances, US EPA www.epa.gov/ozone-layer-protection/ozone-depleting-substances
    HFCs have zero ODP because they do not contain chlorine.
    Checked 2026-10-10.
  2. Basic Ozone Layer Science, US EPA www.epa.gov/ozone-layer-protection/basic-ozone-layer-science
    a process that can take as long as two to five years
    Checked 2026-10-10.

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