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Refrigerant safety classes.Know the gas before you connect.

Safety class, GWP, ozone impact, typical uses and cylinder colours for 38 common refrigerants, with the EU and UK F-gas rules that decide what you can still install and top up.

Letter for toxicity. Number for flammability.

ASHRAE Standard 34 and ISO 817 give every refrigerant a two-part safety class. The letter rates toxicity at low concentrations, the number rates how readily it burns. Tap a class to list the refrigerants in it.

A Lower toxicity
B Higher toxicity
3Higher flammability
B3None in common use
2Flammable
B2Rare (e.g. methyl chloride, R-40)
2LLower flammability
1No flame propagation

B2 and B3 refrigerants are rare in building services. Badge colours on this page are a visual aid only and have no official meaning.

A or B

Class A refrigerants have a workplace exposure limit of 400 ppm by volume or more; class B refrigerants have a lower limit, so they are toxic at smaller concentrations. Any refrigerant can still suffocate you if it displaces air in a small or low-lying space.

1, 2L, 2 or 3

Class 1 shows no flame spread in the standard test. 2L burns slowly and is hard to ignite, 2 is flammable, and 3 is highly flammable with a low lower flammability limit (LFL) or a high heat of combustion.

Blends can change

A blend is classed in its supplied state and in its worst-case composition after a leak. Some non-flammable blends contain small amounts of flammable components, which is one reason never to top up a leaking blend with something else.

  1. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  5. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  6. Regulation (EU) 2024/573 on fluorinated greenhouse gases (EUR-Lex) (opens in a new tab)AR4 basis for HFC GWPs and AR6 for other gases (recital 8); Annex IV product bans; Article 13 servicing bans; Article 10 certification; Annex VII phase-down

Checked 9 Nov 2026

Refrigerant finder. Search, filter, open.

GWP in the list is the IPCC AR4 figure used for CO₂e under the UK (GB) F-gas rules and for HFCs in the EU. Open a refrigerant for its EU and AR5 values, make-up, cylinder markings, the rules that apply at that GWP, and sources.

Showing 38 of 38 refrigerants

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HCFC
Make-up
Single component (chlorodifluoromethane)
ODP
0.055
GWP AR4
1,810 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
Not listed (not an F-gas)
GWP AR5
1,760
Per kg
1.81 t CO₂e (AR4)

Where you will find it

Air conditioning, heat pumps and refrigeration installed before the HCFC phase-out.

Ozone-depleting HCFC. Virgin HCFCs cannot be used, and recovered or reclaimed HCFCs have been banned for topping up or servicing since 1 January 2015. Treat a working R-22 system as end of life: recover the charge and plan a replacement or an approved retrofit.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 352, light green
UK and EU
No set colour: read the label.

Rules at this GWP

  • Ozone-depleting HCFC. No HCFC, virgin, recovered or reclaimed, may be used to top up or service equipment (banned since 1 January 2015 under the ozone regulations). Recover it and send it for destruction or reclamation.
Superheat and subcooling for R-22

Sources

  1. EFCTC / fluorocarbons.org: fluorocarbon molecules, environmental properties and applications (opens in a new tab)ODP and AR4/AR5/AR6 GWP for single-component HCFCs, HFCs and HFOs
  2. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant
  6. NetRegs: Stationary refrigeration, air conditioning and heat pumps - ODS controls (opens in a new tab)Virgin HCFCs cannot be used; recovered or reclaimed HCFCs banned for topping up or servicing since 1 January 2015

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC
Make-up
Single component (trifluoromethane)
ODP
0
GWP AR4
14,800 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
14,800 AR4 for HFC parts, AR6 for others
GWP AR5
12,400
Per kg
14.8 t CO₂e (AR4)

Where you will find it

Low stage of very-low-temperature cascade systems, such as laboratory and medical freezers.

One of the highest GWPs of any refrigerant in use, so even small leaks carry a large CO₂e.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 428, light blue-grey
UK and EU
No set colour: read the label.

Rules at this GWP

  • EU: no virgin gas above GWP 2,500 for servicing refrigeration (reclaimed or recycled allowed until 2030) or, from 2026, air conditioning and heat pumps (until 2032). Banned in most new refrigeration since 2020 to 2025.
  • GB: virgin gas above GWP 2,500 cannot be used to refill refrigeration systems of 40 t CO₂e or more; reclaimed or recycled gas allowed until 2030.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  3. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  4. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Corroborated

Safety and environment

Safety class
A2L Lower toxicity, mildly flammable (low burning velocity)
Type
HFC
Make-up
Single component (difluoromethane)
ODP
0
GWP AR4
675 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
675 AR4 for HFC parts, AR6 for others
GWP AR5
677
Per kg
0.675 t CO₂e (AR4)

Where you will find it

Split and multi-split air conditioning, VRF and air-to-water heat pumps; also a component of many blends.

The usual replacement for R-410A in new equipment, not a drop-in for existing R-410A systems. Use A2L-rated recovery machines and leak detectors.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
Label colour PMS 631, light blue-green
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • EU: above GWP 150, so caught by the 2027 to 2030 bans on new self-contained units, small chillers and splits up to 12 kW (safety-based exceptions allow up to GWP 750 in some cases).
  • GB: no product bans at this GWP at present, but HFC quota is shrinking.
Superheat and subcooling for R-32

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. A-Gas UK: R32 product page (opens in a new tab)R-32 classed A2L; supplied with a left-hand DIN 477-1 valve
  5. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC
Make-up
Single component (1,1,1,2-tetrafluoroethane)
ODP
0
GWP AR4
1,430 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
1,430 AR4 for HFC parts, AR6 for others
GWP AR5
1,300
Per kg
1.43 t CO₂e (AR4)

Where you will find it

Medium-temperature refrigeration, chillers, transport refrigeration and older car air conditioning.

Being replaced by R-513A, R-450A, R-1234ze(E) or R-1234yf depending on the application.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 2975, light blue (sky)
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.
Superheat and subcooling for R-134a

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A2 Lower toxicity, flammable
Type
HFC
Make-up
Single component (1,1-difluoroethane)
ODP
0
GWP AR4
124 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
124 AR4 for HFC parts, AR6 for others
GWP AR5
138
Per kg
0.124 t CO₂e (AR4)

Where you will find it

Mostly aerosol propellant and foam blowing; occasionally a blend component.

Class A2, so more flammable than the A2L refrigerants.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Below GWP 150, so outside most current EU and GB product bans. EU bans on all F-gases in some small self-contained and split equipment start in 2032 and 2035.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. EFCTC / fluorocarbons.org: fluorocarbon molecules, environmental properties and applications (opens in a new tab)ODP and AR4/AR5/AR6 GWP for single-component HCFCs, HFCs and HFOs

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A3 Lower toxicity, highly flammable
Type
Hydrocarbon
Make-up
Single component (propane)
ODP
0
GWP AR4
3.3 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
0.02 AR4 for HFC parts, AR6 for others
GWP AR5
Not given
Per kg
0.0033 t CO₂e (AR4)

Where you will find it

Plug-in commercial cabinets, domestic appliances, monobloc heat pumps, small chillers and portable AC.

Highly flammable. Charge limits, ventilation and ignition-source control are strict; use tools, recovery units and detectors rated for A3.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Not a fluorinated gas, so F-gas quotas and GWP bans do not apply. Flammability, toxicity and pressure rules (EN 378, product standards, DSEAR in the UK) still do.
Superheat and subcooling for R-290

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A3 Lower toxicity, highly flammable
Type
Hydrocarbon
Make-up
Single component (n-butane)
ODP
0
GWP AR4
4 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
0.006 AR4 for HFC parts, AR6 for others
GWP AR5
Not given
Per kg
0.004 t CO₂e (AR4)

Where you will find it

Mainly a minor component of blends such as R-417A; rarely used on its own.

Highly flammable in pure form.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Not a fluorinated gas, so F-gas quotas and GWP bans do not apply. Flammability, toxicity and pressure rules (EN 378, product standards, DSEAR in the UK) still do.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A3 Lower toxicity, highly flammable
Type
Hydrocarbon
Make-up
Single component (isobutane)
ODP
0
GWP AR4
3 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
0 AR4 for HFC parts, AR6 for others
GWP AR5
Not given
Per kg
0.003 t CO₂e (AR4)

Where you will find it

Domestic fridges and freezers and small commercial cabinets.

Highly flammable. Small charges, but never braze on a charged circuit.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Not a fluorinated gas, so F-gas quotas and GWP bans do not apply. Flammability, toxicity and pressure rules (EN 378, product standards, DSEAR in the UK) still do.
Superheat and subcooling for R-600a

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A3 Lower toxicity, highly flammable
Type
Hydrocarbon
Make-up
Single component (propene)
ODP
0
GWP AR4
1.8 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
Not listed (not an F-gas)
GWP AR5
Not given
Per kg
0.0018 t CO₂e (AR4)

Where you will find it

Chillers and commercial refrigeration as a higher-capacity alternative to propane.

Highly flammable; same precautions as R-290.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Not a fluorinated gas, so F-gas quotas and GWP bans do not apply. Flammability, toxicity and pressure rules (EN 378, product standards, DSEAR in the UK) still do.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  3. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)

Checked 9 Nov 2026

Corroborated

Safety and environment

Safety class
B2L Higher toxicity, mildly flammable
Type
Natural (CO₂, ammonia)
Make-up
Single component (ammonia, NH₃)
ODP
0
GWP AR4
0 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
0 AR4 for HFC parts, AR6 for others
GWP AR5
Not given
Per kg
0 t CO₂e (AR4)

Where you will find it

Industrial refrigeration: cold stores, food and drink processing, ice rinks and large chillers.

Toxic and mildly flammable. Needs specific training, gas detection, PPE and an emergency plan.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Not a fluorinated gas, so F-gas quotas and GWP bans do not apply. Pressure, toxicity and machinery-room rules still do.
Superheat and subcooling for R-717

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
Natural (CO₂, ammonia)
Make-up
Single component (carbon dioxide, CO₂)
ODP
0
GWP AR4
1 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
1 AR4 for HFC parts, AR6 for others
GWP AR5
Not given
Per kg
0.001 t CO₂e (AR4)

Where you will find it

Supermarket transcritical and cascade systems, heat pump water heaters and transport refrigeration.

Works at far higher pressures than HFCs, so gauges, hoses and components must be rated for R-744. A large release can displace oxygen.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label.

Rules at this GWP

  • Not a fluorinated gas, so F-gas quotas and GWP bans do not apply. Pressure, toxicity and machinery-room rules still do.
Superheat and subcooling for R-744

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  3. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)

Checked 9 Nov 2026

Corroborated

Safety and environment

Safety class
A2L Lower toxicity, mildly flammable (low burning velocity)
Type
HFO / HCFO
Make-up
Single component (2,3,3,3-tetrafluoropropene)
ODP
0
GWP AR4
4 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
0.501 AR4 for HFC parts, AR6 for others
GWP AR5
Not given
Per kg
0.004 t CO₂e (AR4)

Where you will find it

Car air conditioning, some chillers, and a component of many lower-GWP blends.

Mildly flammable; vehicle systems need equipment approved for R-1234yf.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Below GWP 150, so outside most current EU and GB product bans. EU bans on all F-gases in some small self-contained and split equipment start in 2032 and 2035.
Superheat and subcooling for R-1234yf

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A2L Lower toxicity, mildly flammable (low burning velocity)
Type
HFO / HCFO
Make-up
Single component (trans-1,3,3,3-tetrafluoropropene)
ODP
0
GWP AR4
7 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
1.37 AR4 for HFC parts, AR6 for others
GWP AR5
Not given
Per kg
0.007 t CO₂e (AR4)

Where you will find it

Chillers, high-temperature heat pumps and some commercial refrigeration.

Classed A2L under ASHRAE 34 even though it shows no flame at room temperature in some tests.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Below GWP 150, so outside most current EU and GB product bans. EU bans on all F-gases in some small self-contained and split equipment start in 2032 and 2035.
Superheat and subcooling for R-1234ze(E)

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFO / HCFO
Make-up
Single component (trans-1-chloro-3,3,3-trifluoropropene)
ODP
Negligible
GWP AR4
4.5 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
3.88 AR4 for HFC parts, AR6 for others
GWP AR5
1
Per kg
0.0045 t CO₂e (AR4)

Where you will find it

Low-pressure centrifugal chillers and high-temperature heat pumps.

Runs below atmospheric pressure on the low side, so air and moisture leak in rather than refrigerant leaking out.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label.

Rules at this GWP

  • Below GWP 150, so outside most current EU and GB product bans. EU bans on all F-gases in some small self-contained and split equipment start in 2032 and 2035.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. EFCTC / fluorocarbons.org: HFO and HCFO environmental properties (fluorocarbon molecules table) (opens in a new tab)AR4/AR5/AR6 GWP for HFO-1336mzz(Z) (9 / 2 / 2.08) and HCFO-1233zd(E) (4.5 / 1 / 3.88)
  3. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  4. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  5. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFO / HCFO
Make-up
Single component (cis-1,1,1,4,4,4-hexafluoro-2-butene)
ODP
0
GWP AR4
9 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
2.08 AR4 for HFC parts, AR6 for others
GWP AR5
2
Per kg
0.009 t CO₂e (AR4)

Where you will find it

Centrifugal chillers, high-temperature heat pumps and organic Rankine cycle units.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label.

Rules at this GWP

  • Below GWP 150, so outside most current EU and GB product bans. EU bans on all F-gases in some small self-contained and split equipment start in 2032 and 2035.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. EFCTC / fluorocarbons.org: HFO and HCFO environmental properties (fluorocarbon molecules table) (opens in a new tab)AR4/AR5/AR6 GWP for HFO-1336mzz(Z) (9 / 2 / 2.08) and HCFO-1233zd(E) (4.5 / 1 / 3.88)
  3. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-125/143a/134a (44/52/4)
ODP
0
GWP AR4
3,922 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
3,922 AR4 for HFC parts, AR6 for others
GWP AR5
3,943
Per kg
3.922 t CO₂e (AR4)

Where you will find it

Low- and medium-temperature commercial refrigeration (legacy).

GWP above 2,500: no longer allowed in most new refrigeration, and virgin R-404A cannot be used to top up larger systems. Retrofit or replace.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 021, orange
UK and EU
No set colour: read the label.

Rules at this GWP

  • EU: no virgin gas above GWP 2,500 for servicing refrigeration (reclaimed or recycled allowed until 2030) or, from 2026, air conditioning and heat pumps (until 2032). Banned in most new refrigeration since 2020 to 2025.
  • GB: virgin gas above GWP 2,500 cannot be used to refill refrigeration systems of 40 t CO₂e or more; reclaimed or recycled gas allowed until 2030.
Superheat and subcooling for R-404A

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  6. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant
  7. GOV.UK: Banned F gas for refilling equipment (opens in a new tab)GB ban on virgin F gas above GWP 2,500 for refilling systems of 40 t CO2e or more; reclaimed or recycled allowed until 2030

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-32/125/134a (20/40/40)
ODP
0
GWP AR4
2,107 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
2,107 AR4 for HFC parts, AR6 for others
GWP AR5
1,923
Per kg
2.107 t CO₂e (AR4)

Where you will find it

Commercial refrigeration, often as a retrofit for R-404A.

Zeotropic: charge as liquid and expect temperature glide.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 368, lime green
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.
Superheat and subcooling for R-407A

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  3. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  5. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Corroborated

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-32/125/134a (23/25/52)
ODP
0
GWP AR4
1,774 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
1,774 AR4 for HFC parts, AR6 for others
GWP AR5
1,624
Per kg
1.774 t CO₂e (AR4)

Where you will find it

Air conditioning, heat pumps and chillers; the classic R-22 replacement.

Zeotropic with noticeable glide: always charge as liquid.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 471, medium brown
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.
Superheat and subcooling for R-407C

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  6. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-32/125/134a (30/30/40)
ODP
0
GWP AR4
1,825 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
1,825 AR4 for HFC parts, AR6 for others
GWP AR5
1,674
Per kg
1.825 t CO₂e (AR4)

Where you will find it

Commercial refrigeration as a replacement for R-404A and R-22.

Zeotropic: charge as liquid.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 373, green-yellow-white
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  6. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-32/125 (50/50)
ODP
0
GWP AR4
2,088 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
2,088 AR4 for HFC parts, AR6 for others
GWP AR5
1,924
Per kg
2.088 t CO₂e (AR4)

Where you will find it

Split, multi-split and VRF air conditioning and heat pumps (legacy).

Above GWP 750, so new single splits under 3 kg can no longer use it in the EU or Great Britain. Successors include R-32 and R-454B.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 507, rose
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.
Superheat and subcooling for R-410A

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  6. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant
  7. GOV.UK: Bans on F gas in new products and equipment (updated 27 Aug 2026) (opens in a new tab)Great Britain product bans, including single splits under 3 kg above GWP 750 from 2025

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-125/134a/600 (46.6/50/3.4)
ODP
0
GWP AR4
2,346 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
2,346 AR4 for HFC parts, AR6 for others
GWP AR5
2,127
Per kg
2.346 t CO₂e (AR4)

Where you will find it

Retrofit for R-22 in air conditioning and refrigeration.

Contains a little butane but the blend as supplied is non-flammable.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 354, green
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.
Superheat and subcooling for R-417A

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  3. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  5. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Corroborated

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-125/134a/600a (65.1/31.5/3.4)
ODP
0
GWP AR4
2,729 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
2,729 AR4 for HFC parts, AR6 for others
GWP AR5
2,473
Per kg
2.729 t CO₂e (AR4)

Where you will find it

Retrofit for R-22 in chillers and commercial refrigeration.

GWP above 2,500, so it is caught by the same servicing restrictions as R-404A.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 375, green-yellow
UK and EU
No set colour: read the label.

Rules at this GWP

  • EU: no virgin gas above GWP 2,500 for servicing refrigeration (reclaimed or recycled allowed until 2030) or, from 2026, air conditioning and heat pumps (until 2032). Banned in most new refrigeration since 2020 to 2025.
  • GB: virgin gas above GWP 2,500 cannot be used to refill refrigeration systems of 40 t CO₂e or more; reclaimed or recycled gas allowed until 2030.
Superheat and subcooling for R-422D

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  3. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  5. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Corroborated

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-32/125/134a/600/601a (8.5/45/44.2/1.7/0.6)
ODP
0
GWP AR4
2,265 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
2,264 AR4 for HFC parts, AR6 for others
GWP AR5
2,059
Per kg
2.265 t CO₂e (AR4)

Where you will find it

Retrofit for R-22 in air conditioning and low- and medium-temperature refrigeration.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 2727, blue jay
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  3. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  4. A-Gas UK: R438A product page (opens in a new tab)R-438A classed A1; used as an R-22 replacement
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  6. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Corroborated

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFO/HFC blend
Make-up
R-32/125/1234yf/134a/1234ze(E) (26/26/20/21/7)
ODP
0
GWP AR4
1,387 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
1,386 AR4 for HFC parts, AR6 for others
GWP AR5
1,273
Per kg
1.387 t CO₂e (AR4)

Where you will find it

Low- and medium-temperature commercial refrigeration, replacing R-404A.

Zeotropic: charge as liquid.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 300, gentian blue
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.
Superheat and subcooling for R-448A

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  6. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFO/HFC blend
Make-up
R-32/125/1234yf/134a (24.3/24.7/25.3/25.7)
ODP
0
GWP AR4
1,397 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
1,396 AR4 for HFC parts, AR6 for others
GWP AR5
1,282
Per kg
1.397 t CO₂e (AR4)

Where you will find it

Low- and medium-temperature commercial refrigeration, replacing R-404A.

Zeotropic: charge as liquid.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 7707, greyish blue
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.
Superheat and subcooling for R-449A

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  6. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFO/HFC blend
Make-up
R-134a/1234ze(E) (42/58)
ODP
0
GWP AR4
605 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
601 AR4 for HFC parts, AR6 for others
GWP AR5
547
Per kg
0.605 t CO₂e (AR4)

Where you will find it

Medium-temperature refrigeration and chillers, replacing R-134a.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label.

Rules at this GWP

  • EU: above GWP 150, so caught by the 2027 to 2030 bans on new self-contained units, small chillers and splits up to 12 kW (safety-based exceptions allow up to GWP 750 in some cases).
  • GB: no product bans at this GWP at present, but HFC quota is shrinking.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFO/HFC blend
Make-up
R-32/125/1234yf (11/59/30)
ODP
0
GWP AR4
2,140 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
2,139 AR4 for HFC parts, AR6 for others
GWP AR5
1,945
Per kg
2.14 t CO₂e (AR4)

Where you will find it

Transport refrigeration and low-temperature commercial systems, replacing R-404A.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 2746, metallic blue
UK and EU
No set colour: read the label.

Rules at this GWP

  • Above GWP 750: no new single split systems under 3 kg in the EU or Great Britain since 1 Jan 2025.
  • EU: new split systems over 12 kW restricted from 2029, chillers over 12 kW from 2027, and virgin gas for servicing stationary refrigeration ends in 2032.
Superheat and subcooling for R-452A

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  6. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A2L Lower toxicity, mildly flammable (low burning velocity)
Type
HFO/HFC blend
Make-up
R-32/125/1234yf (67/7/26)
ODP
0
GWP AR4
698 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
697 AR4 for HFC parts, AR6 for others
GWP AR5
676
Per kg
0.698 t CO₂e (AR4)

Where you will find it

Air conditioning, heat pumps and chillers as a lower-GWP alternative to R-410A.

For new equipment designed for A2L refrigerants.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • EU: above GWP 150, so caught by the 2027 to 2030 bans on new self-contained units, small chillers and splits up to 12 kW (safety-based exceptions allow up to GWP 750 in some cases).
  • GB: no product bans at this GWP at present, but HFC quota is shrinking.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A2L Lower toxicity, mildly flammable (low burning velocity)
Type
HFO/HFC blend
Make-up
R-32/1234yf (35/65)
ODP
0
GWP AR4
239 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
237 AR4 for HFC parts, AR6 for others
GWP AR5
238
Per kg
0.239 t CO₂e (AR4)

Where you will find it

Commercial refrigeration and condensing units, replacing R-404A.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • EU: above GWP 150, so caught by the 2027 to 2030 bans on new self-contained units, small chillers and splits up to 12 kW (safety-based exceptions allow up to GWP 750 in some cases).
  • GB: no product bans at this GWP at present, but HFC quota is shrinking.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A2L Lower toxicity, mildly flammable (low burning velocity)
Type
HFO/HFC blend
Make-up
R-32/1234yf (68.9/31.1)
ODP
0
GWP AR4
466 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
465 AR4 for HFC parts, AR6 for others
GWP AR5
467
Per kg
0.466 t CO₂e (AR4)

Where you will find it

Ducted, packaged and split air conditioning and heat pumps; a leading R-410A successor in North America.

For new A2L-rated equipment only, not a retrofit for R-410A.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • EU: above GWP 150, so caught by the 2027 to 2030 bans on new self-contained units, small chillers and splits up to 12 kW (safety-based exceptions allow up to GWP 750 in some cases).
  • GB: no product bans at this GWP at present, but HFC quota is shrinking.
Superheat and subcooling for R-454B

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A2L Lower toxicity, mildly flammable (low burning velocity)
Type
HFO/HFC blend
Make-up
R-32/1234yf (21.5/78.5)
ODP
0
GWP AR4
148 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
146 AR4 for HFC parts, AR6 for others
GWP AR5
146
Per kg
0.148 t CO₂e (AR4)

Where you will find it

Commercial refrigeration and heat pumps where a GWP below 150 is needed.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Below GWP 150, so outside most current EU and GB product bans. EU bans on all F-gases in some small self-contained and split equipment start in 2032 and 2035.
Superheat and subcooling for R-454C

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A2L Lower toxicity, mildly flammable (low burning velocity)
Type
HFO/HFC blend
Make-up
R-744/32/1234yf (3/21.5/75.5)
ODP
0
GWP AR4
148 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
146 AR4 for HFC parts, AR6 for others
GWP AR5
146
Per kg
0.148 t CO₂e (AR4)

Where you will find it

Commercial refrigeration and heat pumps where a GWP below 150 is needed.

Contains a small amount of CO₂; large glide.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044) with a red band on the shoulder or top, because it is flammable.
US label
Label colour PMS 3395, sea foam green
UK and EU
No set colour: read the label. Flammable refrigerant cylinders usually have a left-hand thread valve.

Rules at this GWP

  • Below GWP 150, so outside most current EU and GB product bans. EU bans on all F-gases in some small self-contained and split equipment start in 2032 and 2035.
Superheat and subcooling for R-455A

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  5. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-32/125/13I1 (49/11.5/39.5)
ODP
0
GWP AR4
733 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
733 AR4 for HFC parts, AR6 for others
GWP AR5
696
Per kg
0.733 t CO₂e (AR4)

Where you will find it

Non-flammable alternative to R-410A in air conditioning.

Contains trifluoroiodomethane (R-13I1).

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label.

Rules at this GWP

  • EU: above GWP 150, so caught by the 2027 to 2030 bans on new self-contained units, small chillers and splits up to 12 kW (safety-based exceptions allow up to GWP 750 in some cases).
  • GB: no product bans at this GWP at present, but HFC quota is shrinking.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-125/143a (50/50)
ODP
0
GWP AR4
3,985 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
3,985 AR4 for HFC parts, AR6 for others
GWP AR5
3,985
Per kg
3.985 t CO₂e (AR4)

Where you will find it

Low-temperature commercial and industrial refrigeration (legacy).

GWP above 2,500: same servicing restrictions as R-404A.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 326, blue-green (teal)
UK and EU
No set colour: read the label.

Rules at this GWP

  • EU: no virgin gas above GWP 2,500 for servicing refrigeration (reclaimed or recycled allowed until 2030) or, from 2026, air conditioning and heat pumps (until 2032). Banned in most new refrigeration since 2020 to 2025.
  • GB: virgin gas above GWP 2,500 cannot be used to refill refrigeration systems of 40 t CO₂e or more; reclaimed or recycled gas allowed until 2030.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  3. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  5. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant
  6. GOV.UK: Banned F gas for refilling equipment (opens in a new tab)GB ban on virgin F gas above GWP 2,500 for refilling systems of 40 t CO2e or more; reclaimed or recycled allowed until 2030

Checked 9 Nov 2026

Corroborated

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFC blend
Make-up
R-23/116 (46/54)
ODP
0
GWP AR4
13,396 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
13,504 AR4 for HFC parts, AR6 for others
GWP AR5
11,698
Per kg
13.396 t CO₂e (AR4)

Where you will find it

Very-low-temperature cascades for laboratory and medical storage.

Very high GWP.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 302, dark blue (navy)
UK and EU
No set colour: read the label.

Rules at this GWP

  • EU: no virgin gas above GWP 2,500 for servicing refrigeration (reclaimed or recycled allowed until 2030) or, from 2026, air conditioning and heat pumps (until 2032). Banned in most new refrigeration since 2020 to 2025.
  • GB: virgin gas above GWP 2,500 cannot be used to refill refrigeration systems of 40 t CO₂e or more; reclaimed or recycled gas allowed until 2030.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  3. Linde: Refrigerants product data summary (opens in a new tab)Safety group, ODP and AR4 GWP for established refrigerants (supplier data, 2012 edition)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  5. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Corroborated

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFO/HFC blend
Make-up
R-1234yf/134a (56/44)
ODP
0
GWP AR4
631 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
629 AR4 for HFC parts, AR6 for others
GWP AR5
573
Per kg
0.631 t CO₂e (AR4)

Where you will find it

Chillers and medium-temperature refrigeration as a lower-GWP replacement for R-134a.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
Label colour PMS 7460, sky blue
UK and EU
No set colour: read the label.

Rules at this GWP

  • EU: above GWP 150, so caught by the 2027 to 2030 bans on new self-contained units, small chillers and splits up to 12 kW (safety-based exceptions allow up to GWP 750 in some cases).
  • GB: no product bans at this GWP at present, but HFC quota is shrinking.
Superheat and subcooling for R-513A

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)
  5. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
B1 Higher toxicity, no flame propagation
Type
HFO / HCFO
Make-up
R-1336mzz(Z)/1130(E) (74.7/25.3)
ODP
Negligible
GWP AR4
7 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
2 AR4 for HFC parts, AR6 for others
GWP AR5
2
Per kg
0.007 t CO₂e (AR4)

Where you will find it

Low-pressure centrifugal chillers, mainly as an R-123 replacement.

Higher toxicity class (B): machine-room detection and ventilation matter.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label.

Rules at this GWP

  • Below GWP 150, so outside most current EU and GB product bans. EU bans on all F-gases in some small self-contained and split equipment start in 2032 and 2035.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. AHRI: Chemical, physical and environmental properties of A2L refrigerants (chapter 2) (opens in a new tab)ASHRAE 34 / ISO 817 safety classes, including A1, A2L, A2, A3, B1 and B2L examples
  4. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  5. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)

Checked 9 Nov 2026

Verified

Safety and environment

Safety class
A1 Lower toxicity, no flame propagation in the standard test
Type
HFO/HFC blend
Make-up
R-1234ze(E)/227ea (91.1/8.9)
ODP
0
GWP AR4
293 used for UK (GB) F-gas CO₂e and EU HFC figures
GWP EU 2024/573
288 AR4 for HFC parts, AR6 for others
GWP AR5
299
Per kg
0.293 t CO₂e (AR4)

Where you will find it

Chillers and heat pumps as a non-flammable alternative to R-134a.

Cylinder and label

US (AHRI)
Light green-grey container (RAL 7044).
US label
No PMS label colour listed in AHRI Guideline N (2017)
UK and EU
No set colour: read the label.

Rules at this GWP

  • EU: above GWP 150, so caught by the 2027 to 2030 bans on new self-contained units, small chillers and splits up to 12 kW (safety-based exceptions allow up to GWP 750 in some cases).
  • GB: no product bans at this GWP at present, but HFC quota is shrinking.

Sources

  1. German Environment Agency (UBA): GWP of selected compounds and mixtures, AR4, AR5 and Regulation (EU) 2024/573 (March 2026) (opens in a new tab)GWP100 values under IPCC AR4, IPCC AR5 and the EU F-gas Regulation 2024/573
  2. ASHRAE Factsheet 1: Update on New Refrigerants Designations and Safety Classifications (October 2026) (opens in a new tab)ASHRAE 34 safety groups for refrigerants designated since 2010
  3. BITZER Refrigerant Report: complete refrigerant data table (opens in a new tab)ISO 817 safety group for each refrigerant (compressor manufacturer data)
  4. ASHRAE: Refrigerant designations (opens in a new tab)Official R-numbers and blend compositions (mass %)

Checked 9 Nov 2026

Verified

No refrigerants match. Try another R-number or clear the filters.

Check the nameplate and the label. The equipment nameplate and the cylinder label are the final word on what a system holds. Verified entries have the safety class confirmed by ASHRAE or AHRI and the GWP by a government or EU source; Corroborated entries are supported by two independent technical sources.

Swaps by application. What replaced what.

Typical refrigerants you will meet in each kind of equipment, from older high-GWP gases to the lowest-GWP options. This is not a retrofit guide: a different safety class usually means different equipment, so follow the manufacturer.

Typical refrigerants by application: older, current lower-GWP and lowest-GWP options
ApplicationOlder or high GWPLower GWP (HFC and HFO)Lowest GWP and natural
Split AC and air-to-air heat pumpsA1R-22A1R-410AA2LR-32A2LR-454BA2LR-452BA1R-466AA3R-290
Air-to-water heat pumpsA1R-410AA1R-407CA2LR-32A2LR-454BA3R-290A1R-744A2LR-454C
ChillersA1R-22A1R-134aA1R-407CA1R-410AA1R-513AA1R-450AA1R-515BA2LR-32A2LR-454BA2LR-1234ze(E)A1R-1233zd(E)A1R-1336mzz(Z)B1R-514AA3R-290B2LR-717
Supermarket and central refrigerationA1R-404AA1R-507AA1R-22A1R-448AA1R-449AA1R-407AA1R-407FA1R-744A2LR-455AA2LR-454CA3R-290
Plug-in cabinetsA1R-404AA1R-134aNo common optionA3R-290A3R-600aA1R-744
Domestic fridges and freezersA1R-134aNo common optionA3R-600a
Transport refrigerationA1R-404AA1R-134aA1R-452AA1R-744
Car air conditioningA1R-134aNo common optionA2LR-1234yfA1R-744
Industrial plantA1R-22No common optionB2LR-717A1R-744
Very low temperature (around −80 °C)A1R-23A1R-508BNo common optionNo common option

Cylinder colours. A hint, never proof.

Colour conventions differ between the US and Europe, and both now point you to the label. Pick a region.

AHRI Guideline N. One grey for everything.

Until the late 2010s every refrigerant in North America had its own cylinder paint colour. With more and more blends arriving, AHRI changed Guideline N: from 1 January 2020 all new refrigerant containers should be one light green-grey (RAL 7044, matched to PMS 413). The individual PMS colours live on, but only on labels and cartons. Guideline N is a recommendation rather than law, and older painted cylinders did not have to be repainted, so you may still see both.

Non-flammable refrigerant, US style. Light green-grey RAL 7044 container with a sky-blue PMS 2975 label stripe, as used for R-134a
Non-flammable (A1)RAL 7044 body. The label, here in R-134a’s sky blue, tells you what is inside.
Flammable refrigerant, US style. RAL 7044 container with a red band on the shoulder and a light blue-green label stripe, as used for R-32
Flammable (A2L, A2, A3)Same grey, plus a red band (PMS 185) on the shoulder or top. A2L cylinders also come with a left-hand thread valve.
Pre-2020 painted cylinder. Older stock painted rose all over, the former R-410A colour
Older stockPre-2020 cylinders painted in the old colour, such as rose for R-410A. Still legal to use; still check the label.

Label colours (PMS) from Guideline N

Swatches are screen approximations of the Pantone references. Use them as a hint, never as proof of contents.

R-22PMS 352 light greenR-23PMS 428 light blue-greyR-32PMS 631 light blue-greenR-134aPMS 2975 light blue (sky)R-404APMS 021 orangeR-407APMS 368 lime greenR-407CPMS 471 medium brownR-407FPMS 373 green-yellow-whiteR-410APMS 507 roseR-417APMS 354 greenR-422DPMS 375 green-yellowR-438APMS 2727 blue jayR-448APMS 300 gentian blueR-449APMS 7707 greyish blueR-452APMS 2746 metallic blueR-455APMS 3395 sea foam greenR-507APMS 326 blue-green (teal)R-508BPMS 302 dark blue (navy)R-513APMS 7460 sky blueContainer bodyRAL 7044 / PMS 413 light green-greyFlammable bandPMS 185 red
  1. AHRI Guideline N: Assignment of Refrigerant Container Colors (2017) (opens in a new tab)Uniform RAL 7044 container colour from 2020, red band for flammables, PMS label colours per refrigerant
  2. ACHR News: Revised AHRI guideline removes color assignments for refrigerant containers (June 2016) (opens in a new tab)Move to one light green-grey (RAL 7044) colour by 2020; labels become the main identifier
  3. MSA Safety: Changes to refrigerant cylinder color code (March 2020) (opens in a new tab)Existing stock need not be repainted; flammables keep a red band; recovery cylinders excluded
  4. Contracting Business: Industry webinar clarifies gray cylinder color codes and safety features for A2Ls (Nov 2025) (opens in a new tab)A2L cylinders carry a red band at the top and a left-hand thread valve
  5. UNEP OzonAction technical brief: Labelling refrigerant cylinders (opens in a new tab)AHRI colour system discontinued; labelling is now the main way to identify cylinder contents
  6. BCGA TIS 6 rev 3: Gas cylinder identification, label and colour code requirements (opens in a new tab)In the UK the label is the primary identifier; EN 1089-3 shoulder colours by hazard; body colour is the supplier's choice
  7. ACR Journal: Take care and respect the humble cylinder (Sept 2020) (opens in a new tab)UK supplier practice: recovery cylinders with a yellow top, receivers yellow top with black ring; read the label
  8. A-Gas UK: R32 product page (opens in a new tab)R-32 classed A2L; supplied with a left-hand DIN 477-1 valve

Checked 9 Nov 2026

F-gas rules. What you can still fit and fill.

Great Britain and the EU now run separate F-gas regimes. Northern Ireland follows the EU rules. Dates below are the ones most relevant to installers; each rule has exceptions, so check the regulation before quoting a job.

AR4

IPCC Fourth Assessment Report GWPs. Used for CO₂e on labels, leak-check bands and quotas under the GB F-gas rules, and for HFCs under EU Regulation 2024/573.

EU 2024/573

Uses AR4 for HFCs and AR6 for other gases such as HFOs, so blend values can differ slightly from AR4 (R-454B: 466 AR4, 465 EU).

AR5 and AR6

Newer IPCC figures. Some manufacturers quote AR5 or AR6, so always check which basis a datasheet uses before comparing.

EU: Regulation 2024/573

  1. No new single splits under 3 kg with GWP 750 or more. No new self-contained refrigeration at GWP 150 or more. Virgin gas of GWP 2,500 or more banned for servicing refrigeration.
  2. No F-gases in new domestic fridges and freezers. GWP 2,500 or more banned for servicing AC and heat pumps (reclaimed or recycled until 2032).
  3. GWP 150 limit for new plug-in, monobloc and self-contained AC and heat pumps up to 50 kW, split air-to-water up to 12 kW and chillers up to 12 kW. Chillers over 12 kW limited to under 750.
  4. Split air-to-air up to 12 kW limited to GWP under 150; splits over 12 kW under 750.
  5. Virgin gas of GWP 750 or more banned for servicing stationary refrigeration. No F-gases in new self-contained units and chillers up to 12 kW.
  6. No F-gases in new splits up to 12 kW from 2035. HFC quota falls in steps to zero in 2050.

Many bans allow a higher GWP (up to 750) where safety rules make a lower-GWP refrigerant impossible.

Great Britain: GB F-gas regulation

  • Already banned: HFCs above GWP 2,500 in new stationary refrigeration (except below −50 °C), HFCs above 150 in new domestic and hermetic commercial fridges, and F-gases above 150 in new multipack systems of 40 kW or more (cascade primary circuits under 1,500 excepted).
  • Since 1 Jan 2025: no new single splits under 3 kg above GWP 750, with exceptions including air-to-water and cooling-only product systems.
  • Refilling: virgin F-gas above GWP 2,500 cannot be used in refrigeration systems of 40 t CO₂e or more. Reclaimed or recycled gas is allowed until 2030.
  • Phase-down: HFC quota steps down from 31% to 24% of the baseline in January 2027 and again in 2030. In 2026 Defra decided not to legislate for a faster schedule yet but says reform will follow, so watch for changes.

Who can do the work

  • GB: anyone installing, servicing, leak checking, recovering or decommissioning F-gas equipment needs a certificate, and the business needs company certification. Category I covers all work on any size of system; Category II covers systems under 3 kg (6 kg if hermetically sealed and labelled) plus leak checks that do not open the circuit; Category III is recovery under 3 kg; Category IV is leak checking only.
  • EU: Implementing Regulation 2024/2215 replaced the old categories with A1 and A2 (F-gases and hydrocarbons), B (CO₂), C (ammonia), D (recovery) and E (leak checks). Existing holders must update their knowledge, with refresher training at least every 7 years and the first deadline on 12 March 2029.

CO₂e quick check

Charge in kg × GWP ÷ 1,000 = tonnes CO₂e. Uses AR4 for the GB leak-check band and shows the EU 2024/573 figure alongside.

6.26t CO₂e (AR4)

EU 2024/573 value: 6.26 t CO₂e

GB leak checks: every 12 months, or 24 months with a leak detection system.

GB leak-check bands: under 5 t none; 5 to under 50 t every 12 months; 50 to under 500 t every 6 months; 500 t and over every 3 months with a fixed leak detection system. Detection doubles the interval. Hermetically sealed systems under 10 t CO₂e have no set interval. EU bands are set in Article 5 of Regulation 2024/573.

  1. Regulation (EU) 2024/573 on fluorinated greenhouse gases (EUR-Lex) (opens in a new tab)AR4 basis for HFC GWPs and AR6 for other gases (recital 8); Annex IV product bans; Article 13 servicing bans; Article 10 certification; Annex VII phase-down
  2. Commission Implementing Regulation (EU) 2024/2215 (copy published by AFEC) (opens in a new tab)New EU certificate categories A1, A2, B (CO2), C (ammonia), D and E; repeals 2015/2067; transition for existing holders
  3. GOV.UK: Bans on F gas in new products and equipment (updated 27 Aug 2026) (opens in a new tab)Great Britain product bans, including single splits under 3 kg above GWP 750 from 2025
  4. GOV.UK: Banned F gas for refilling equipment (opens in a new tab)GB ban on virgin F gas above GWP 2,500 for refilling systems of 40 t CO2e or more; reclaimed or recycled allowed until 2030
  5. NetRegs: Stationary refrigeration, air conditioning and heat pumps - F gas controls (opens in a new tab)Leak check intervals by tonnes CO2e; labelling; company certification
  6. legislation.gov.uk: Regulation (EU) 2015/2067 Article 3 (as retained in GB) (opens in a new tab)GB certificate categories I to IV and the 3 kg / 6 kg hermetic thresholds
  7. UK Regulated Professions Register: F gas handler (opens in a new tab)Reserved activities, retained 2015/2067, Fluorinated Greenhouse Gases Regulations 2015, qualifying bodies
  8. FETA: F-Gas update (18 May 2026) (opens in a new tab)GB quota steps from 31% to 24% of baseline in January 2027; Defra will not legislate in 2026; NI follows EU rules
  9. The Chemical Engineer: UK delays tougher HFC phasedown targets (4 June 2026) (opens in a new tab)Defra kept the existing GB phase-down and plans further reform

Checked 9 Nov 2026

Charge limits. The room sets the ceiling.

For A2L, A2 and A3 refrigerants the question is how much gas could end up in the room if it all leaked. The answer depends on the refrigerant’s LFL, the room size and the height of the unit. These are the principles; the numbers come from the standard and the manufacturer’s instructions.

EN 378 steps

EN 378 sets three reference charges as multiples of the LFL: about 4 m³, 26 m³ and 130 m³ worth (m1, m2, m3). For propane that is roughly 150 g, 1 kg and 5 kg. Above each step more conditions apply: occupancy, location class and room volume.

Product standards

Appliance standards set their own limits. IEC 60335-2-89 lets commercial cabinets carry up to 500 g of A3 or 1.2 kg of A2L per circuit under conditions. The 2022 revision of IEC 60335-2-40 allows larger flammable charges in AC and heat pumps where extra safety measures are designed in.

On site

The installation manual gives a minimum room floor area for the actual charge and mounting height. Measure the room, add any extra pipe charge to the total and stay inside the limit. If the room is too small, you need a different unit, not a workaround.

  1. Tecumseh: Charge limits for A2L refrigerants in the EU (EN 378) (opens in a new tab)EN 378 charge steps m1, m2, m3 as multiples of LFL; access categories; location classes; detector at 25% of LFL
  2. Danfoss: New charge limits for flammable refrigerants (IEC 60335-2-89) (opens in a new tab)IEC 60335-2-89 raised per-circuit limits to 500 g for A3 and 1.2 kg for A2/A2L, with conditions
  3. EIA: Adoption of new air-conditioning safety standard (IEC 60335-2-40), May 2022 (opens in a new tab)Revised IEC 60335-2-40 allows larger flammable charges when extra safety measures are built in

Checked 9 Nov 2026

Handle with certification. And a detector.

Refrigerant work is restricted for good reasons: frostbite, asphyxiation, fire, toxic decomposition products and very high pressures.

Only certified engineers handle refrigerant

Opening a refrigerant circuit, recovering, charging or venting refrigerant is work for a qualified, certified engineer working for a certified business. If you are not certified, do not connect gauges, cut pipes or open valves. Releasing F-gases on purpose is illegal.

Know the class

Check the nameplate and the cylinder label before you start. A2L and A3 refrigerants need tools, recovery units, vacuum pumps and detectors rated for flammable gases.

Ventilate and remove ignition

Work in a ventilated space, keep sparks, flames and hot surfaces away, and use a suitable leak detector before and during the job. Flammable refrigerant collects low down: think about drains, pits and basements. Ammonia is toxic and rises; ventilate high. Storing and working with flammable refrigerants falls under DSEAR in Great Britain.

Purge before brazing

Recover the charge fully, evacuate, and flow oxygen-free nitrogen through the pipework before heat goes near it. Fluorinated refrigerants break down into toxic, acidic gases in a flame.

Respect pressure

R-744 runs at several times the pressure of HFCs, and every cylinder is a pressure vessel. Keep cylinders upright, secured and cool, never overfill a recovery cylinder, and never heat one with a flame.

Work it out on site.

Superheat and subcooling calculators for over 20 refrigerants, plus courses to help you build your skills.