True or False: Even though HFC refrigerants have essentially zero ozone depletion potential, they are still regulated as 'substitute' refrigerants under the venting prohibition and related Section 608 requirements.
Not quite. The answer is A: True
Section 608's venting prohibition reaches substitute refrigerants as well as ozone-depleting ones. HFCs have essentially zero ozone depletion potential, but they are still non-exempt substitutes (only a short list such as CO2, nitrogen, water, and certain hydrocarbons in specific end-uses is exempt), so recovery equipment, technician certification, and the sales restriction still apply to them. Note the leak-repair rules under § 82.157 apply only to appliances with 50 lb or more of an ozone-depleting refrigerant; HFC appliances face leak repair under the separate AIM Act rule (40 CFR Part 84, Subpart C) instead.
Reference: 40 CFR Part 82 § 82.154(a)(1) (Venting prohibition covers non-exempt substitute refrigerants)
Checked against the official text
Read the eCFR text current through 2026-10-30 of § 82.154. Paragraph (a)(1) prohibits knowingly venting any refrigerant and lists the exempt substitutes (e.g., CO2, nitrogen, water, certain hydrocarbons); HFCs are not on that list. § 82.152 defines 'substitute' to include hydrofluorocarbons.