Environmental test chambers often rely on refrigeration systems to create and control low temperatures. If those systems contain fluorinated gases, or F gases, the equipment may be affected by F-gas regulations covering refrigerant use, leak checking, record keeping and servicing.
For chamber owners, the practical question in 2026 is whether the chamber’s refrigerant, charge size, condition and service history still make it practical to maintain. Older systems using high global warming potential, or GWP, refrigerants may need closer attention, especially where future refrigerant supply and servicing options could become more limited.
Short answer: what changed in 2026 and who does it affect?
In 2026, there is no blanket requirement for chamber owners to replace existing equipment containing F gas. The main update concerns the wider HFC refrigerant phase-down. On 15 May 2026, Defra confirmed that it would not introduce legislation during 2026 to change the phase-down steps due to apply from 1 January 2027. The existing 2027 step will therefore remain in place while further reform is considered.
For chamber owners, the immediate priorities remain:
- identifying the refrigerant in each chamber
- checking its GWP and refrigerant charge
- understanding whether leak checks and record keeping apply
- planning ahead for equipment using high-GWP refrigerants
- using correctly qualified engineers and, where required, certified service companies
- considering whether service, refurbishment or replacement is the most practical long-term route
A chamber using an older refrigerant can often remain in service. The key issue is whether it can continue to be maintained reliably and within the rules that apply to its refrigeration system.
What are F gases and why do they matter?
F gases are fluorinated greenhouse gases. They include hydrofluorocarbons, or HFCs, perfluorocarbons and sulphur hexafluoride. HFCs are widely associated with refrigeration, air conditioning and heat pump applications.
In an environmental test chamber, refrigerant is used by the cooling system to reach and maintain the required test conditions. The chamber itself is not automatically a compliance issue simply because it has a refrigeration circuit. What matters is the specific equipment, refrigerant type, charge size, system condition and work being carried out.
F-gas regulations are intended to reduce emissions of these gases and encourage a move towards lower-GWP alternatives. For equipment owners, that translates into practical obligations around preventing leaks, using qualified personnel, maintaining appropriate records and observing restrictions on certain refrigerants.
GWP and CO2 equivalent explained
Global warming potential, or GWP, shows how strongly a gas contributes to global warming compared with carbon dioxide. A higher GWP means that even a relatively small refrigerant charge can represent a significant CO2 equivalent value.
That CO2 equivalent figure matters because several F gas rules UK chamber owners need to consider are based on tonnes of CO2 equivalent, rather than the refrigerant weight alone.
The calculation is:
Refrigerant charge in metric tonnes × refrigerant GWP = tonnes CO2 equivalent
For example, GOV.uk uses a 10 kg charge of R-404A, with a GWP of 3,922, to show a CO2 equivalent of 39.2 tonnes. This explains why a relatively modest refrigerant charge in an older high-GWP system can still be significant for leak-checking thresholds or service restrictions.
Common examples include:
- R-404A – GWP 3,922
- R-507A – GWP 3,985
- R-407C – GWP 1,774
- R-410A – GWP 2,088
- R-448A – GWP 1,386
The refrigerant label, equipment documentation and service records should help establish what is in the chamber. Don’t assume the refrigerant based on the chamber’s age, manufacturer or intended temperature range.
The 2026 HFC phase-down position
The HFC phase-down is a supply-side measure intended to reduce the quantity of HFCs placed on the market in Great Britain over time. It does not mean all HFC refrigerants are immediately prohibited in existing equipment.
Defra consulted on potential changes to the Great Britain HFC phase-down schedule in late 2025. Following that consultation, its update of 15 May 2026 confirmed that no legislation would be introduced during 2026 to change the phase-down steps starting on 1 January 2027. Further reform remains under consideration.
For chamber owners, this means:
- do not assume a new 2026 rule has made your existing chamber unusable
- do not treat current refrigerant access as guaranteed for the life of the chamber
- include refrigerant type and serviceability in lifecycle planning
- review ageing high-GWP systems before an urgent repair forces a rushed decision
For an older chamber, this usually means looking ahead rather than reacting to a single announcement. A refrigeration system that is reliable today may still deserve closer review if it uses a high-GWP refrigerant, has required repeated top-ups or supports test work that cannot tolerate extended downtime.
What the high-GWP refrigerant refill ban means
The high-GWP service ban becomes relevant when a refrigeration system needs refrigerant added after a leak or repair.
Virgin, unused F gas cannot be used to refill an existing refrigeration system where both of the following apply:
- The system contains F gas equivalent to 40 tonnes CO2 equivalent or more
- The refrigerant has a GWP above 2,500
This restriction can affect larger systems using high-GWP refrigerants such as R-404A and R-507A. GOV.uk lists the relevant charge thresholds as approximately 10.2 kg for R-404A and 10 kg for R-507A.
The refrigerant name alone doesn’t determine whether the ban applies. Instead, the system must meet or exceed the 40-tonne CO₂ equivalent threshold. Although certain types of equipment are excluded, including military equipment and equipment designed to cool products below -50°C, owners should confirm that an exclusion applies to their specific chamber against official guidance before relying on it.
Can an existing chamber still be serviced?
Yes, in many cases. An older chamber can often continue in service where it remains reliable, the refrigeration system can be maintained and its performance still matches the test programme.
Where a chamber is affected by the high-GWP virgin refrigerant ban, the service engineer needs to assess the available options rather than simply adding new refrigerant. These can include reclaimed refrigerant, eligible recycled refrigerant, a technically compatible retrofit or replacement of the refrigeration system or chamber.
GOV.uk states that in Great Britain, reclaimed refrigerant above 2,500 GWP may still be used in affected existing equipment until 1 January 2030. Recovered and recycled refrigerant from similar equipment may also be used until that date where it has been recovered by the equipment owner or the business servicing the equipment.
Reclaimed or recycled refrigerant is not a universal answer. Availability, cost, system condition and compatibility all affect whether it is a sensible repair route. A chamber that requires repeated refrigerant work may justify a wider review of its refrigeration system, controls and remaining service life.
Leak checks and record keeping
A refrigerant leak is more than a maintenance issue as it can interrupt testing, increase repair costs and trigger specific F-gas duties where the equipment reaches the relevant CO2 equivalent thresholds.
GOV.uk states that leak-checking frequency depends on both the quantity of F gas in the equipment and the gas’s GWP. For common stationary equipment, the standard thresholds are:
- 5 to less than 50 tonnes CO2 equivalent – at least every 12 months
- 50 to less than 500 tonnes CO2 equivalent – at least every 6 months
- 500 tonnes CO2 equivalent or more – leak detection requirements apply, with additional checking obligations
Where an automatic leak detection system is fitted, the permitted interval between leak checks can be doubled.
For equipment containing 5 tonnes CO2 equivalent or more, operators must keep F-gas records for five years. The file should include the refrigerant type and quantity, gas added during maintenance, mandatory leak-check results, recovery or disposal activity and the details of companies used to install, service or decommission the equipment.
A well-kept service file gives a chamber owner a clearer view of the asset. It shows whether refrigerant has been added repeatedly, whether leaks are recurring and whether planned maintenance is still controlling risk or merely reacting to faults.
Choosing a compliant service partner
Refrigerant work calls for more than general mechanical or electrical competence. Engineers handling F gas should hold their own relevant qualifications for the work they perform, including servicing, maintenance, leak checks, refrigerant recovery and decommissioning of stationary refrigeration systems.
Where a company services stationary F-gas equipment operated by another business, the company, including a sole trader, must hold certification from an approved body. The company must also demonstrate that it employs sufficiently trained staff and has procedures for safe F-gas handling and emission reduction.
When choosing a provider for F-gas chamber servicing, ask:
- Does the engineer hold the qualification needed for the planned work?
- Is the service company certified where certification is required?
- Will the report identify refrigerant type, charge and work completed?
- Will you receive leak-check and refrigerant handling records where applicable?
- Can the provider assess the wider chamber condition, rather than only the immediate fault?
- Can they explain the options for a high-GWP system without assuming a refrigerant retrofit will work?
Reclaimed refrigerant, retrofit or replacement?
The best next step comes down to reliability, test criticality, refrigerant choice and the condition of the chamber as a whole.
1. Continue servicing with an appropriate refrigerant route
Continued servicing can make sense where the chamber is reliable, cooling performance remains stable and a compliant refrigerant route is available. Planned maintenance gives owners the opportunity to identify leaks, deteriorating components and performance issues before a failure disrupts testing.
A chamber that has needed minimal refrigerant intervention and still meets its test profile is very different from one that has a history of repeated leaks or can’t maintain low-temperature performance.
2. Retrofit the refrigeration system
A lower-GWP refrigerant may be technically viable in some systems, though it isn’t automatically a direct replacement for the existing gas.
A retrofit can affect cooling capacity, operating pressures, lubricants, control settings and component compatibility. Any refrigerant change needs a proper engineering assessment and should follow the equipment manufacturer’s recommendations.
3. Refurbish the chamber
Refurbishment becomes worthwhile where the chamber structure and core test capability remain sound, but ageing refrigeration, controls, electrics, seals or other components are affecting reliability.
This route can extend the useful life of an asset, but the scope needs to match the chamber’s condition and the performance your test programme demands. ETS service and maintenance support can help identify faults, maintenance needs and wider refurbishment considerations.
4. Replace with a lower-GWP chamber solution
Replacement often makes more sense when failures are recurring, repair costs are becoming difficult to justify or the chamber no longer supports the required test conditions.
When reviewing replacement equipment, discuss refrigerant strategy alongside temperature range, humidity performance, working volume, controls, noise, energy use and installation constraints. ETS eco-friendly test chambers may be worth discussing where climatic testing, reduced operating energy demand and lower noise are priorities.
Common mistakes to avoid
Assuming every old chamber needs replacing
An older chamber doesn’t need replacing just because it contains F gas or uses a high-GWP refrigerant. Start with the refrigerant type, charge size, CO2 equivalent, condition and recent service history.
Looking only at the refrigerant name
R-404A and R-507A are above the 2,500 GWP limit, but charge size still determines whether the 40-tonne CO2 equivalent refill restriction applies. Calculate the CO2 equivalent before drawing conclusions.
Treating calibration as F-gas compliance
Environmental chamber calibration confirms how the chamber is measuring and controlling conditions at agreed test points. It does not replace leak checks, refrigerant records or work by qualified F-gas personnel.
Waiting for a breakdown before reviewing options
A chamber that uses high-GWP refrigerant or has a history of leaks deserves attention before it suffers a major failure. A planned review creates time to compare continued servicing, refurbishment and replacement without pressure from a stopped test programme.
Assuming a retrofit will always work
A lower-GWP alternative may be available, but refrigerant compatibility and cooling performance must be assessed for the specific system. This is particularly relevant for demanding low-temperature chambers, where changes to the refrigeration circuit can affect the chamber’s ability to achieve or maintain its test conditions.
How ETS can help
ETS supports environmental chamber owners with service, maintenance, calibration, refurbishment and replacement planning.
A chamber review can help establish its current condition, identify recurring faults and clarify whether the equipment still supports the test programme. Where refrigerant work is needed, it needs to be completed by appropriately qualified engineers and assessed against the current F-gas regulations.
If you’re unsure about an ageing chamber, speak to us about its refrigerant, service history, test conditions and long-term role in your facility. We can help you assess whether continued maintenance, refurbishment or replacement is likely to offer the best value and lowest disruption.
This article is for general guidance only, not legal advice. Always check the latest guidance from the relevant regulator and confirm the requirements that apply to your specific equipment and test setup.
FAQs
Do F-gas regulations apply to environmental test chambers?
They can apply where an environmental chamber contains F gas in a stationary refrigeration system. Relevant duties can include leak checks, record keeping, qualified refrigerant handling and restrictions on certain refill activities. The exact position is shaped by the refrigerant, charge size, CO2 equivalent and equipment use.
What changed in the F-gas rules for 2026?
As of the Defra update published on 15 May 2026, the Government will not legislate during 2026 to alter the HFC phase-down steps beginning on 1 January 2027. The existing 2027 step will continue while further reforms are considered.
Can R-404A or R-507A still be used in an existing chamber?
For refrigeration systems at or above 40 tonnes CO2 equivalent, virgin refrigerant above 2,500 GWP can’t be used for refilling. This includes examples such as R-404A and R-507A. Reclaimed refrigerant and eligible recycled refrigerant may still be used in affected existing equipment in Great Britain until 1 January 2030.
Do F-gas engineers have to be qualified?
Yes. Individuals handling F gas must hold the relevant qualification for their work. Companies servicing stationary F-gas equipment for another operator must also hold the necessary company certification.
Does chamber calibration cover F-gas obligations?
No. Calibration and F-gas compliance are separate activities. Calibration verifies chamber measurement performance, while F-gas rules cover refrigerant handling, leak checks, record keeping and service restrictions.
