C&G 2079-11 F-Gas Category I cheat sheet

UK F-gas controls cover HFCs, PFCs and SF6; ODS controls cover CFCs, HCFCs, halons and other ozone-depleting substances.

Category I certification permits work on all RAC equipment, including leak checking, charging, recovery, recycling and decommissioning.

CO2e = refrigerant charge (kg) × GWP ÷ 1,000; this value determines leak-check frequency and record thresholds.

Common GWPs: R-134a 1430, R-32 675, R-410A 2088, R-404A 3922, R-407C 1774; CO2 has GWP 1.

HCFC R-22 has ODP 0.055 and GWP 1810; virgin HCFC supply for refrigeration is phased out under ODS rules.

F-gas equipment must be labelled with refrigerant type, charge in kg and CO2e, and GWP; labels must remain legible and maintained.

Deliberate venting of F-gas or ODS is prohibited; recovered refrigerant must be recycled, reclaimed or destroyed by authorised routes.

Certified companies and personnel must be registered; records of certification and refrigerant transactions support compliance checks.

The operator is legally responsible for leak prevention, periodic checks, record keeping, recovery and use of certified personnel.

F-gas leakage adds to global warming; ODS leakage also depletes stratospheric ozone and increases UV reaching the surface.

A 1 kg release of R-410A has a CO2e of about 2.09 tonnes; a 1 kg release of R-404A is about 3.92 tonnes.

Leakage lowers system efficiency and capacity, raising energy use and indirect CO2 emissions over the equipment life.

Records must be kept for at least five years and produced to an enforcement officer on request.

Only competent, certified persons may install, service, leak check or recover controlled refrigerants; company certification is separate from personal certification.

Penalties for breaches include improvement notices, prohibition notices, fines and prosecution under environmental and F-gas legislation.

Environmental harm from ODS includes ozone depletion; from F-gases includes long atmospheric lifetime and high GWP.

ASHRAE safety groups: A1 lower toxicity/no flame propagation; A2L lower flammability; A3 higher flammability; B classes higher toxicity.

R-32, R-454B and R-1234yf are A2L; R-290 (propane) and R-600a (isobutane) are A3; R-410A and R-134a are A1.

Refrigerant vapour is denser than air and can accumulate in pits, basements and plant rooms, displacing oxygen.

Liquid refrigerant at atmospheric pressure boils near -30 to -50 °C and causes frostbite on contact with skin or eyes.

Refrigerant exposed to flames or high temperature can decompose to hydrogen fluoride, carbonyl fluoride and other toxic products.

Oxygen-free nitrogen is the only acceptable pressure-test gas for RAC systems; oxygen and air can form explosive mixtures with oil.

Never mix refrigerants; mixed refrigerant cannot be returned to original specification and may produce unexpected pressures and temperatures.

A refrigerant leak in a confined space requires evacuation, ventilation and appropriate respiratory protection before entry.

Recovery cylinders must be approved for the refrigerant, within test date, undamaged and fitted with correct valve and dip tube.

Cylinder fill limit is by weight and commonly 80% of water capacity; overfilling can cause hydraulic rupture or relief-valve release.

Cylinders are stored upright, secured, valve-protected, away from heat, ignition sources and direct sunlight.

Cylinder colour codes and UN labels identify contents; never rely on colour alone-check the valve label and markings.

PPE selection follows risk assessment: safety glasses, chemical gloves, safety footwear, and flame-retardant or respiratory protection where required.

Risk assessment hierarchy: eliminate exposure, substitute safer refrigerant, engineer controls, adopt safe system of work, then PPE.

Cylinder transport requires valve caps, restraint, ventilation and segregation from oxidisers and flammable gases.

A cylinder that has been heated or damaged must be treated as hazardous and isolated; do not attempt to move it if pressure is rising.

CO2e thresholds: 5–50 t check every 12 months; 50–500 t every 6 months; ≥500 t every 3 months.

Hermetically sealed equipment below 10 t CO2e is exempt from periodic leak checks but still subject to leak prevention and record duties.

A verified automatic leak detection system halves the required check frequency for the 50–500 t and ≥500 t bands.

Leak detection systems must be verified at least every 12 months and records of verification retained.

Records include equipment ID, refrigerant, charge, CO2e, check date, findings, repairs, technician and leak-detection verification.

Leaks must be repaired as soon as practicable; repaired areas require follow-up checks and records.

Containment measures include minimising joints, protecting pipework, controlling vibration, using correct materials and avoiding unnecessary charge.

Reporting obligations include records of refrigerant purchases, recovery, recycling, reclamation and destruction, retained for five years.

Installation must follow manufacturer instructions, EN 378 principles and applicable building, electrical and refrigerant safety standards.

Pressure testing uses oxygen-free nitrogen with a regulated source; test pressure must not exceed component or system design limits.

Pressure tests are increased in stages and held at each stage; test pressure, duration, gas and result are recorded.

Never use oxygen, compressed air or refrigerant to pressure test; oil and oxygen can ignite.

Triple evacuation uses nitrogen breaks between vacuum stages to remove moisture and non-condensables.

Final vacuum is commonly 500 microns (0.67 mbar) or manufacturer's specification; a standing vacuum test confirms no rise.

Charge refrigerant by weight using a calibrated scale; record actual charge and adjust superheat/subcooling to commissioning data.

Commissioning checks include electrical safety, rotation, controls, safety devices, leak test, insulation and documentation.

Service work begins with system identification, refrigerant check, risk assessment, isolation and recovery of refrigerant where required.

Recovery removes refrigerant; recycling cleans it on site; reclamation reprocesses to specification with laboratory analysis.

Recovery cylinders must be labelled with refrigerant, owner, date and gross/tare weights; mixed refrigerants are labelled as mixtures.

Recovered refrigerant must not be vented; it is recycled, reclaimed, destroyed or returned to an authorised processor.

Before brazing, recover refrigerant and purge with nitrogen; refrigerant or oil exposed to flame forms toxic decomposition products.

Decommissioning includes recovery of all refrigerant, recording quantity, disconnecting, labelling, removing components and authorised disposal.

Compressor oil may contain dissolved refrigerant; do not drain or open until pressure is released and refrigerant recovered.

After servicing, leak test, evacuate, recharge by weight, record work and verify safety controls before return to service.