F-gas rules for air conditioning: what businesses must do

Written by the Commercial Air Conditioning team. Last reviewed 31 October 2026.

Short answer

If your air conditioning holds 5 tonnes CO2 equivalent of F-gas refrigerant or more, you — as the operator — must have it leak-checked by a certified engineer at least every 12 months (6 months from 50 tonnes, 3 months from 500 tonnes), repair leaks promptly and keep records for at least five years.

Who the rules apply to

The F-gas rules place duties on the operator: the person or business with actual control over the equipment. In a leased building that is often the tenant, but leases differ — check who controls and maintains the system.

In England, Scotland and Wales the GB F-gas Regulation applies (the assimilated version of Regulation (EU) No 517/2014, as amended). Northern Ireland follows the EU F-gas Regulation (EU) 2024/573: for HFC systems its leak-check thresholds and intervals match the GB rules, and it also requires checks on equipment holding 1 kg or more of certain other fluorinated gases, such as HFO refrigerants.

CO2 equivalent and thresholds

Thresholds are set in tonnes of CO2 equivalent (CO2e): the refrigerant charge in kg multiplied by its global warming potential (GWP), divided by 1,000.

R410A (GWP 2,088): 5 tonnes CO2e is reached at about 2.4 kg
R32 (GWP 675): 5 tonnes CO2e is reached at about 7.4 kg
R407C (GWP 1,774): about 2.8 kg

Leak-check frequencies

5 to under 50 tonnes CO2e: at least every 12 months (24 months with automatic leak detection)
50 to under 500 tonnes CO2e: at least every 6 months (12 months with automatic leak detection)
500 tonnes CO2e and above: at least every 3 months (6 months with automatic leak detection, which is required at this size)
Hermetically sealed equipment labelled as such is exempt below 10 tonnes CO2e

Repairs and records

If a leak is found it must be repaired without undue delay, and the system checked again within one month of the repair. For equipment that needs leak checks, keep records for at least five years: refrigerant type and quantity, quantities added and recovered, leak-check dates and results, and the company and engineer who did the work.

Refrigerant bans and the phase-down

Since 1 January 2025, new single split air conditioning systems in Great Britain holding less than 3 kg of refrigerant cannot use a refrigerant with a GWP of 750 or more — which is why most new small splits now use R32. HFC supply is also being cut in steps under the phase-down, and the GB quota falls from 31% to 24% of the baseline from 1 January 2027, which can push up the cost of higher-GWP refrigerants such as R410A.

R22, an HCFC, has been banned for servicing since 1 January 2015, so R22 systems cannot be topped up.

Certification

Engineers who install, service, leak-check or recover refrigerant must hold the appropriate F-gas qualification, and companies doing this work for others need an F-gas company certificate. Ask for both numbers on any quote.

Questions

Does a small split system need leak checks?

Only if its charge reaches 5 tonnes CO2e. For R410A that is about 2.4 kg, which many commercial splits exceed; for R32 it is about 7.4 kg, so many small R32 systems fall below it. Equipment labelled as hermetically sealed is exempt below 10 tonnes CO2e.

Who keeps the F-gas records?

The operator must make sure records are kept; contractors usually maintain them on the operator's behalf.

Sources

Related services

This guide is general information, not legal advice. Rules can change; check the current position with the relevant authority for your building.