The short answer
The GB Fluorinated Greenhouse Gases Regulations 2015 control how the refrigerant gases inside air conditioning are handled. They require that anyone who installs, commissions, services or decommissions equipment containing fluorinated refrigerant holds an F-Gas qualification and works for an F-Gas-registered company, that leaks are minimised and checked, and that refrigerant is recovered properly at end of life. DIY refrigerant work is illegal, and Northern Ireland follows separate retained EU rules.
F-gas is shorthand for fluorinated greenhouse gases — the refrigerants that make air conditioning work. Because these gases have a high global-warming potential if they escape, GB law tightly controls who handles them and how. This guide explains the F-gas rules in plain terms so you understand why a certified engineer is mandatory and what your obligations are as an owner. It is general information, not legal advice; check gov.uk and DEFRA guidance for the current detail.
F-gas at a glance
- Legislation (GB) Fluorinated Greenhouse Gases Regulations 2015
- Who can handle refrigerant F-Gas-certified engineers only
- Company requirement F-Gas-registered business
- DIY refrigerant work Illegal
- Northern Ireland Separate retained EU F-gas rules
- Enforcement (GB) Environment Agency / regulators
What F-gas regulations control
Fluorinated refrigerants are extremely effective at moving heat, which is exactly why air conditioning uses them — but if they leak into the atmosphere they are potent greenhouse gases. The GB Fluorinated Greenhouse Gases Regulations 2015, together with DEFRA guidance, set out a framework to keep those gases contained across the whole life of the equipment. The rules cover competence (who may work on systems), leak prevention and checking, record-keeping, recovery of refrigerant, and a long-term phase-down of the most damaging gases in favour of lower-impact alternatives.
For a plain explanation of the refrigerant itself and why it matters to how your system works, see air con refrigerant explained. The key point for owners is that the refrigerant circuit is sealed, regulated and not something to be opened casually.
Who is allowed to handle refrigerant
This is the part that affects every owner. Under F-gas law, only a person holding the relevant F-Gas qualification, working for an F-Gas-registered company, may install, commission, service or decommission equipment that contains fluorinated refrigerant. There is no homeowner exemption for the refrigerant circuit. That means the cooling part of any installation — charging, connecting, leak-testing and recovering gas — is legally off-limits to anyone without certification. The duties that fall on owners and engineers include:
- Use a certified engineer for any work that opens or charges the refrigerant circuit.
- Prevent and repair leaks promptly — deliberately releasing refrigerant is prohibited.
- Keep records of servicing and, on larger systems, of mandatory leak checks.
- Recover refrigerant properly at end of life rather than venting it.
Leak checks and record-keeping
F-gas requires that equipment is built and maintained to minimise leaks, and that leaks are repaired promptly when found. Larger systems, measured by the refrigerant charge they hold, are subject to mandatory periodic leak checks at intervals that increase with charge size, and operators must keep records of those checks. Most single domestic splits hold a small charge and fall below the threshold that triggers formal leak-check duties, but the duty not to deliberately release refrigerant and to repair any leak applies to everyone, regardless of system size.
| Duty | Who it falls on |
|---|---|
| Use a certified engineer | Owner / operator |
| Prevent and repair leaks | Operator and engineer |
| Leak checks on larger systems | Operator (records kept) |
| Recover refrigerant at end of life | Certified engineer |
End of life and the phase-down
When a system is scrapped, the refrigerant must be recovered by a certified engineer, not vented to atmosphere. Separately, F-gas drives a long-term phase-down that limits the supply of high global-warming-potential refrigerants, which is why newer equipment increasingly uses lower-impact gases. As an owner this mainly affects you indirectly: it can influence the availability and cost of refrigerant for older systems over time, and it is one more reason to keep your system well maintained so it does not need topping up. For end-of-life planning, read air con lifespan and air con re-gas explained.
A note on Northern Ireland and what to do
Great Britain and Northern Ireland operate under different F-gas regimes — Northern Ireland continues to apply retained EU rules — so if you are in NI, check the position that applies there. Everywhere in the UK, the practical takeaway is the same: choose an F-Gas-certified installer from a registered company, keep your service and any leak records, and never let anyone uncertified open the refrigerant circuit. For how certification is verified before you let an engineer near your system, read air con installer certification.
Verify F-Gas credentials
Before work begins, confirm your engineer holds an F-Gas qualification and their company is F-Gas-registered. Keep service and leak records for the life of the system.
Frequently asked questions
What does F-gas stand for?
F-gas means fluorinated greenhouse gases — the refrigerants used in air conditioning. The GB Fluorinated Greenhouse Gases Regulations 2015 control how they are handled to limit their environmental impact.
Who can legally handle air con refrigerant?
Only an F-Gas-certified engineer working for an F-Gas-registered company. There is no homeowner exemption, so any refrigerant work by an uncertified person is illegal in Great Britain.
Do I need leak checks on a home system?
Most single domestic splits hold too little refrigerant to trigger formal periodic leak checks, but the duty to prevent and repair leaks applies to everyone. Larger systems have mandatory checks by charge size.
Are the rules the same across the UK?
No. Great Britain applies the Fluorinated Greenhouse Gases Regulations 2015, while Northern Ireland follows separate retained EU F-gas rules. Check the regime that applies where you live.
Sources & further reading
- gov.uk — Fluorinated Greenhouse Gases Regulations 2015 (GB F-gas)
- DEFRA — F-gas: guidance for users, producers and traders
- gov.uk — F-gas in Northern Ireland (retained EU rules)
- REFCOM — F-Gas Register and company registration
This guide is general information, not a site-specific survey or a substitute for a quote from an F-Gas-certified installer. Installation, servicing and refrigerant handling are legally restricted to F-Gas-certified engineers.