HRAI ODP Refrigerant Handling cheat sheet

ODP (ozone depletion potential) is a relative number scaled so CFC-11 = 1.0; it expresses how much stratospheric ozone a unit mass of a substance can destroy relative to CFC-11.

Reference values: CFC-11 and CFC-12 = 1.0, HCFC-22 = 0.055, HCFC-141b = 0.11, HCFC-142b = 0.065, carbon tetrachloride = 1.1, methyl bromide = 0.6, HFCs and HFOs = 0.

ODP depends on the molecule's chlorine/bromine content and atmospheric lifetime; bromine is roughly 45-60 times more ozone-destructive per atom than chlorine, so halons carry high ODP despite low mass.

ODS definition: a substance that contains chlorine or bromine and can reach the stratosphere to catalytically destroy ozone; fluorine alone does not confer ODP, so HFCs are not ODS.

Montreal Protocol control groups: Annex A (CFC-11/12/113/114/115, halons), Annex B (other CFCs, carbon tetrachloride, methyl chloroform), Annex C (HCFCs and HBFCs), Annex E (methyl bromide); HFCs are handled under the Kigali Amendment, not as ODS.

GWP is a separate metric (CO2 = 1 over 100 years); a refrigerant can have ODP = 0 but high GWP (e.g., R-404A, R-410A), so ODP compliance does not imply climate compliance.

Recovery/recycling rule: refrigerant must be recovered before opening a circuit, and recovered ODS may only be reused if it meets the specification for the equipment or is reprocessed/reclaimed to AHRI 700 purity.

Leak detection and recordkeeping: ODS refrigerant charges above the applicable threshold require periodic leak checks, repair within the regulated period after a detected leak, and documented records of charge, recovery, and disposal.

Cylinder identification: recovered/refrigerant cylinders must be DOT/TC-rated for the contents, never overfilled (typical fill limit ~80% of water capacity by liquid), and labeled with the refrigerant identity and hazard class.

Venting prohibition: intentional release of ODS refrigerant to the atmosphere is prohibited; recovery equipment must evacuate the system to the required vacuum level before final opening or disposal of the appliance.

De minimis exemption: small charges (commonly 5 lb or less of ODS in some jurisdictions) may be exempt from certain recovery/leak-repair rules; the exemption does not authorize venting of ODS.

Recycling vs. reclaiming: recycling is field cleaning (oil/acid/moisture removal) without verifying composition; reclaiming requires chemical analysis and certification to AHRI 700 and is the only route for resale or use in a different owner's equipment.

Blend handling: zeotropic blends (e.g., R-407C, R-410A) must be charged as liquid and cannot be fractionally topped off; recovered blend composition must be verified before reuse.

Retrofit rule: replacing an ODS refrigerant with a non-ODS substitute requires removing/mineral-oil-to-POE lubricant change where specified, replacing filter-driers, and updating the equipment label to show the new refrigerant charge.

Safety: ODS refrigerants are typically nonflammable but asphyxiating; recovery cylinders must be kept below their pressure rating, away from heat, and never filled with a refrigerant other than the one labeled.

Disposal: appliance disposal requires recovery of the refrigerant before shredding or landfill; recovered refrigerant that cannot be reclaimed must be destroyed by an approved destruction process, not vented.