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SESK: Stuff Everyone Should Know · sesk.info/epa-venting-exempt

Which of these is exempt from the EPA venting prohibition in any application?

Nitrogen, along with carbon dioxide and water.

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  1. R-134a
  2. R-22
  3. Nitrogen ✔

Why: The venting rule lists a few substitutes that are exempt, including carbon dioxide, nitrogen and water in any application. Refrigerants like R-134a and R-22 are not exempt, so they must be recovered.

Huh, didn't know that: The exemption list also covers some hydrocarbons, such as propane (R-290) in certain household and retail equipment.

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Why was the air conditioner so annoyed? It just needed to vent.
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References

Answer: Nitrogen. The venting rule lists a few substitutes that are exempt, including carbon dioxide, nitrogen and water in any application. Refrigerants like R-134a and R-22 are not exempt, so they must be recovered.

  1. 40 CFR 82.154 Prohibitions (Cornell LII) www.law.cornell.edu/cfr/text/40/82.154
    Nitrogen in any application
    Checked 2026-10-10.
  2. 40 CFR 82.154 Prohibitions (Cornell LII) www.law.cornell.edu/cfr/text/40/82.154
    Water in any application
    Checked 2026-10-10.
  3. 40 CFR 82.154 (Cornell LII) www.law.cornell.edu/cfr/text/40/82.154
    Propane (R-290) in retail food refrigerators and freezers
    Checked 2026-10-10.

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