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C&G 2079-11 F-Gas Category I study materials
C&G 2079-11 F-Gas Category I study resources

C&G 2079-11 F-Gas Category I practice questions

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Question 1F-gas and ODS regulations, legal duties and environmental impact

What does the abbreviation GWP stand for in F-gas regulations?

  1. Greenhouse weight percentage
  2. Gas warming property
  3. Global warming potential Correct answer.
  4. General warming pressure

Explanation

GWP is a relative measure of how much heat a greenhouse gas traps in the atmosphere compared with carbon dioxide over a set period, usually 100 years. It is used to convert the mass of an F-gas into tonnes of CO2 equivalent for regulatory thresholds.

Question 2F-gas and ODS regulations, legal duties and environmental impact

Which of the following refrigerants is an ozone-depleting substance controlled by ODS regulations?

  1. R-410A
  2. R-22 Correct answer.
  3. R-134a
  4. R-32

Explanation

R-22 is a hydrochlorofluorocarbon containing chlorine, so it depletes stratospheric ozone and falls under ODS controls. R-134a, R-410A and R-32 are HFCs or HFC blends with no chlorine and are controlled as F-gases, not as ODS.

Question 3F-gas and ODS regulations, legal duties and environmental impact

Which legislation is the main UK control on ozone-depleting substances such as CFCs and HCFCs?

  1. The F-gas Regulation and its quota system
  2. The COSHH Regulations and safety data sheets
  3. The Pressure Systems Safety Regulations
  4. The ODS Regulation Correct answer.

Explanation

The retained ODS Regulation controls production, use, recovery and destruction of ozone-depleting substances. The F-gas Regulation deals with fluorinated greenhouse gases, not the ozone-depleting CFCs and HCFCs themselves.

Question 4F-gas and ODS regulations, legal duties and environmental impact

For stationary refrigeration equipment containing 5 tCO2e or more but less than 50 tCO2e, what is the maximum interval between statutory leak checks?

  1. Every six months
  2. Every twelve months Correct answer.
  3. Every three months
  4. Every month

Explanation

The regulation sets a 12-month maximum interval for equipment at or above 5 tCO2e and below 50 tCO2e. More frequent checks apply at larger charge sizes, and intervals are halved where a certified leak detection system is fitted.

Question 5F-gas and ODS regulations, legal duties and environmental impact

For how long must an operator keep records of F-gas leak checks, repairs and gas quantities?

  1. At least one year
  2. At least five years Correct answer.
  3. Only until the next service
  4. At least ten years

Explanation

Records must be kept for at least five years and made available to the regulator on request. They provide an audit trail for leak checks, repairs, gas recovery and charge changes.

Question 6F-gas and ODS regulations, legal duties and environmental impact

What is the correct legal approach for F-gas recovered from refrigeration equipment during service?

  1. Pour it down a drain
  2. Recover it for recycling or destruction Correct answer.
  3. Release it slowly to atmosphere
  4. Burn it in an open fire

Explanation

F-gases must not be vented to atmosphere; recovered gas must be handled by certified personnel and sent for recycling, reclamation or destruction. This prevents emissions of high-GWP gases and keeps the gas traceable.

Question 7F-gas and ODS regulations, legal duties and environmental impact

Which of these substances is a fluorinated greenhouse gas controlled by the F-gas Regulation?

  1. Carbon dioxide (R-744)
  2. Ammonia (R-717)
  3. Propane (R-290)
  4. R-134a Correct answer.

Explanation

R-134a is an HFC and is a fluorinated greenhouse gas listed as an F-gas. Ammonia, carbon dioxide and propane are natural refrigerants and are not controlled as F-gases.

Question 8F-gas and ODS regulations, legal duties and environmental impact

What does ODP measure?

  1. Its pressure in a cylinder
  2. Its ozone-destroying ability Correct answer.
  3. Its toxicity to humans
  4. Its flammability rating

Explanation

ODP compares a substance's ozone-destroying effect with that of CFC-11, which is assigned an ODP of 1. It is separate from GWP, which measures climate impact.

Question 9F-gas and ODS regulations, legal duties and environmental impact

A system contains 10 kg of R-410A with a GWP of 2088. What is the charge expressed in tonnes of CO2 equivalent?

  1. 2.09 tCO2e
  2. 208.8 tCO2e
  3. 0.21 tCO2e
  4. 20.88 tCO2e Correct answer.

Explanation

Multiply the mass in kilograms by the GWP and divide by 1000: 10 × 2088 ÷ 1000 = 20.88 tCO2e. This figure determines which leak-check frequency and record-keeping duties apply.

Question 10F-gas and ODS regulations, legal duties and environmental impact

Equipment has a charge of 60 tCO2e. How often must statutory leak checks be carried out?

  1. Every three months
  2. Every two years
  3. Every six months Correct answer.
  4. Every twelve months

Explanation

At 50 tCO2e or more but below 500 tCO2e, leak checks are required at least every six months. A certified leak detection system would allow the interval to be doubled to twelve months.

Question 11F-gas and ODS regulations, legal duties and environmental impact

A system containing 600 tCO2e has a fixed leak detection system installed and operating. What is the maximum interval between manual leak checks?

  1. Every three months
  2. Every twelve months
  3. Every month
  4. Every six months Correct answer.

Explanation

At 500 tCO2e or more a leak detection system is mandatory, and manual checks must be at least every six months when it is fitted. Without a detection system the interval is three months.

Question 12F-gas and ODS regulations, legal duties and environmental impact

Who is legally permitted to carry out leak checks on stationary F-gas refrigeration equipment?

  1. A certified F-gas handler Correct answer.
  2. A general building contractor
  3. Any competent maintenance technician
  4. The equipment owner without certification

Explanation

Leak checking is a regulated activity that must be done by personnel holding the appropriate F-gas certificate, normally through a certified employer. General maintenance staff without F-gas certification cannot perform it.

Question 13F-gas and ODS regulations, legal duties and environmental impact

What must happen before refrigeration equipment containing F-gas is permanently decommissioned?

  1. The refrigerant must be vented to speed up the process
  2. The equipment must be painted and resold
  3. The circuit must be flushed with water
  4. A certified person must recover the refrigerant Correct answer.

Explanation

The operator must ensure refrigerant is recovered before dismantling or disposal, and the recovery must be done by certified personnel. Venting is prohibited and water flushing does not remove the legal duty.

Question 14F-gas and ODS regulations, legal duties and environmental impact

What is the main environmental concern associated with HFC refrigerants?

  1. They are all highly toxic
  2. They destroy stratospheric ozone
  3. They cause acid rain
  4. They have high global warming potential Correct answer.

Explanation

HFCs generally have zero ozone-depletion potential but can have very high GWP, so leaks contribute significantly to climate change. Toxicity and acid rain are not the regulatory reason HFCs are controlled.

Question 15F-gas and ODS regulations, legal duties and environmental impact

What is the ozone-depletion potential of most HFC refrigerants?

  1. Negative
  2. Greater than 1
  3. Between 0.5 and 1
  4. Zero Correct answer.

Explanation

HFCs contain no chlorine or bromine, so their ODP is zero and they do not directly destroy stratospheric ozone. They are controlled because of their global warming potential.

Question 16F-gas and ODS regulations, legal duties and environmental impact

Which information must be recorded for equipment containing 5 tCO2e or more of F-gas?

  1. Only the equipment serial number
  2. The date of the last service and the technician's name
  3. The gas type and charge, checks and repairs Correct answer.
  4. The purchase price of the gas and its supplier

Explanation

Records must show the gas type and charge, leak checks, repairs and gas recovered or added. These records must be kept for at least five years.

Question 17F-gas and ODS regulations, legal duties and environmental impact

What is the operator's duty when a leak of F-gas is detected?

  1. Wait until the next scheduled maintenance visit
  2. Seal the leak with tape and record it as repaired
  3. Top up the charge and keep the system running
  4. Repair it promptly and verify the repair Correct answer.

Explanation

The operator must arrange repair as soon as practicable and then check that the repair has been effective, normally within one month. Simply topping up or delaying repair breaches the leak-control duty.

Question 18F-gas and ODS regulations, legal duties and environmental impact

Which is a legal requirement for a business that installs or services F-gas equipment?

  1. It must be a member of a trade association
  2. It must hold a company F-gas certificate Correct answer.
  3. It must sell only natural refrigerants
  4. It must employ at least ten engineers

Explanation

Companies carrying out regulated F-gas activities must hold the relevant company certification and use certified personnel. Trade association membership and company size are not legal conditions.

Question 19F-gas and ODS regulations, legal duties and environmental impact

Which statement correctly distinguishes GWP from ODP?

  1. Both measure the same environmental effect
  2. GWP measures ozone destruction and ODP measures climate change
  3. GWP measures climate impact; ODP measures ozone destruction Correct answer.
  4. ODP applies only to HFCs and GWP only to CFCs

Explanation

GWP compares a gas's heat-trapping effect with CO2, while ODP compares its ozone-destroying effect with CFC-11. A gas can have a high GWP and zero ODP, as most HFCs do.

Question 20F-gas and ODS regulations, legal duties and environmental impact

What must appear on a label for an F-gas container placed on the market?

  1. The gas, its GWP and CO2e mass Correct answer.
  2. The date of manufacture and the test pressure
  3. The cylinder colour code and the tare weight
  4. The supplier's name, address and telephone number

Explanation

Containers must be labelled to say they contain fluorinated greenhouse gases, with the GWP and the quantity expressed in CO2 equivalent. This supports traceability and safe handling.

Question 21F-gas and ODS regulations, legal duties and environmental impact

Under the HFC phase-down, what percentage of the baseline is the 2030 target for placing HFCs on the market?

  1. 21% Correct answer.
  2. 100%
  3. 63%
  4. 45%

Explanation

The phase-down steps reduce the HFC quota from the baseline to 21% by 2030. The 45% step applies from 2021 and the 63% step from 2018.

Question 22F-gas and ODS regulations, legal duties and environmental impact

A system contains 3 kg of R-404A with a GWP of 3922. What is the charge in tCO2e and the minimum leak-check frequency?

  1. 117.7 tCO2e and every 3 months
  2. 11.77 tCO2e and every 6 months
  3. 11.77 tCO2e and every 12 months Correct answer.
  4. 1.18 tCO2e and every 12 months

Explanation

3 × 3922 ÷ 1000 = 11.766 tCO2e, which is at least 5 but below 50 tCO2e, so checks are due every 12 months. The six-month interval starts at 50 tCO2e.

Question 23F-gas and ODS regulations, legal duties and environmental impact

A switchgear unit contains 0.5 kg of SF6 with a GWP of 22,800. What is the CO2 equivalent charge?

  1. 0.0114 tCO2e
  2. 1.14 tCO2e
  3. 114 tCO2e
  4. 11.4 tCO2e Correct answer.

Explanation

0.5 × 22,800 ÷ 1000 = 11.4 tCO2e. This exceeds 5 tCO2e, so leak checks and records are required for the equipment.

Question 24F-gas and ODS regulations, legal duties and environmental impact

What is the correct fate of R-22 recovered from an old refrigeration system in the UK?

  1. It may be reused indefinitely in any refrigeration system
  2. It may be topped up with HFCs and kept in service
  3. It may be vented to atmosphere if the system is outdoors
  4. It must be recovered and destroyed by an approved process Correct answer.

Explanation

R-22 is an HCFC controlled as an ODS, and the UK no longer permits its use for maintenance, so recovered R-22 must be destroyed by an approved facility. Mixing it with HFCs would also create an illegal and unrecorded refrigerant.

Question 25F-gas and ODS regulations, legal duties and environmental impact

In F-gas law, what does 'placing on the market' mean?

  1. Operating the equipment after installation
  2. Installing the equipment at the end user's site
  3. Recovering gas during decommissioning
  4. Supplying or making it available to another party Correct answer.

Explanation

Placing on the market covers supplying or making available the product or gas to another party, whether paid for or free. It is distinct from installing, operating or decommissioning the equipment.

Question 26F-gas and ODS regulations, legal duties and environmental impact

Which of these actions is prohibited under F-gas legislation when handling a refrigerant that contains HFCs?

  1. Returning recovered refrigerant to a certified reclamation facility
  2. Releasing the refrigerant into the atmosphere after servicing Correct answer.
  3. Storing recovered refrigerant in a suitably rated recovery cylinder
  4. Recycling refrigerant on site for reuse in the same equipment

Explanation

The F-gas Regulation bans the deliberate release of fluorinated greenhouse gases into the atmosphere, including during servicing, maintenance and disposal. Recovered gas must be recovered, and then recycled, reclaimed or destroyed by suitably qualified arrangements.

Question 27F-gas and ODS regulations, legal duties and environmental impact

Which of these refrigerants is controlled as an ozone-depleting substance?

  1. R-744
  2. R-22 Correct answer.
  3. R-134a
  4. R-410A

Explanation

R-22 is HCFC-22, a hydrochlorofluorocarbon that contains chlorine and therefore has a measurable ozone-depletion potential. Its production and use are controlled under the ODS Regulation, and it is not an HFC.

Question 28F-gas and ODS regulations, legal duties and environmental impact

In F-gas legislation, who is the 'operator' of stationary refrigeration equipment?

  1. The business controlling its technical operation Correct answer.
  2. The wholesaler that supplied the original refrigerant charge
  3. The manufacturer that assembled and supplied the compressor
  4. The technician who carries out the scheduled leak checks

Explanation

The operator is the natural or legal person who has actual control over the day-to-day technical functioning of the equipment. Legal duties such as leak checks, record keeping and repair therefore sit with the operator, not with the servicing contractor.

Question 29F-gas and ODS regulations, legal duties and environmental impact

For how long must an operator keep the F-gas records for stationary refrigeration equipment?

  1. 5 years Correct answer.
  2. 3 years
  3. 10 years
  4. 1 year

Explanation

Records of leak checks, repairs, refrigerant added and recovery must be retained for at least five years. They must be made available to the competent authority on request.

Question 30F-gas and ODS regulations, legal duties and environmental impact

Above which charge, in tonnes of CO2 equivalent, does stationary refrigeration equipment first become subject to statutory leak checks?

  1. 500 tCO2e
  2. 1 tCO2e
  3. 5 tCO2e Correct answer.
  4. 50 tCO2e

Explanation

The leak-check obligation starts at a charge of 5 tonnes CO2 equivalent. Below that threshold the equipment must still be operated so as to avoid leakage, and gas must still be recovered, but periodic statutory checks are not required.

Question 31F-gas and ODS regulations, legal duties and environmental impact

A leak on a commercial refrigeration system has just been repaired. Within what period must the follow-up leak check be carried out?

  1. Before the system is restarted
  2. Within seven days of the repair
  3. By the next scheduled annual check
  4. Within one month of the repair Correct answer.

Explanation

After a leak has been repaired, the operator must ensure a follow-up check is carried out within one month to confirm the repair has been effective. The repair itself must be completed without undue delay.

Question 32F-gas and ODS regulations, legal duties and environmental impact

A firm wants to start installing and servicing split air-conditioning units containing HFCs. What authorisation does the firm itself need?

  1. A personal certificate held by the managing director
  2. A company certificate covering the relevant activities Correct answer.
  3. A waste carrier registration for recovered refrigerant
  4. A refrigerant purchase licence issued by the supplier

Explanation

Businesses that install, service, maintain or decommission F-gas equipment must hold a company certificate covering those activities. The technicians who actually handle the refrigerant must separately hold the appropriate personal qualification.

Question 33F-gas and ODS regulations, legal duties and environmental impact

Under the ODS Regulation, what is the position on using recycled HCFC-22 to service existing refrigeration equipment?

  1. It is allowed if the equipment was installed before 2000
  2. It is allowed for a further ten years under a phase-out quota
  3. It is allowed provided the technician records the quantity used
  4. It is prohibited, including the use of recycled or reclaimed material Correct answer.

Explanation

The use of virgin and recycled HCFCs for servicing and maintenance was banned once the phase-out took effect. Recovered R-22 must therefore be recovered and then destroyed or reclaimed for feedstock-type uses permitted by the Regulation, not used to recharge systems.

Question 34F-gas and ODS regulations, legal duties and environmental impact

Which GWP values must be used when calculating the CO2 equivalent charge of an F-gas system?

  1. The values given in the latest IPCC assessment report
  2. The values published by the refrigerant manufacturer on the cylinder
  3. The highest value published for any blend component
  4. The values listed in the Annexes to the F-gas Regulation Correct answer.

Explanation

Calculations must use the GWP values set out in the Annexes to the Regulation, which are based on the IPCC Fourth Assessment Report 100-year values. Using a different published figure can change the CO2 equivalent charge and therefore the applicable obligations.

Question 35F-gas and ODS regulations, legal duties and environmental impact

Which detail must be shown on the label of a new stationary refrigeration unit charged with an HFC?

  1. The charge in tonnes of CO2 equivalent and the GWP Correct answer.
  2. The date of the next scheduled leak check
  3. The name of the technician who carried out commissioning
  4. The pressure test certificate number

Explanation

Equipment containing F-gases must be labelled with the refrigerant designation and, where required, the charge expressed in CO2 equivalent together with the GWP. The label must be legible and durable and must remain on the equipment.

Question 36F-gas and ODS regulations, legal duties and environmental impact

Equipment has an automatic leak detection system fitted. How often must the system itself be checked for correct operation?

  1. Every five years
  2. Only when a leak alarm is triggered
  3. At least every 12 months Correct answer.
  4. Every three months

Explanation

Where a leak detection system is installed, the operator must ensure it is checked for proper functioning at least once every 12 months. The detection system allows the leak-check interval for the equipment itself to be extended, so its reliability matters.

Question 37F-gas and ODS regulations, legal duties and environmental impact

The HFC phase-down baseline is calculated from the average annual HFC placed on the market during which period?

  1. 2015 to 2018
  2. 2005 to 2008
  3. 1990 to 1995
  4. 2009 to 2012 Correct answer.

Explanation

The baseline is the average quantity of HFCs placed on the market each year over 2009 to 2012, expressed in CO2 equivalent. Future annual limits are then set as percentages of that baseline.

Question 38F-gas and ODS regulations, legal duties and environmental impact

Since 1 January 2015, which equipment could no longer be placed on the market if it contained HFCs with a GWP of 150 or more?

  1. Domestic refrigerators and freezers Correct answer.
  2. Transport refrigeration units for lorries
  3. Stationary fire protection systems
  4. Industrial process chillers over 500 kW

Explanation

Placing domestic refrigerators and freezers containing HFCs with a GWP of 150 or more on the market has been prohibited since 1 January 2015. The ban applies to the equipment being placed on the market, not to equipment already in service.

Question 39F-gas and ODS regulations, legal duties and environmental impact

The HFC quota system under the F-gas Regulation applies directly to which activity?

  1. Exporting HFC-containing equipment to another country
  2. Charging a new split unit with pre-filled HFC
  3. Importing bulk HFCs into the country for sale Correct answer.
  4. Servicing a refrigeration system with reclaimed HFC

Explanation

The quota limits the total CO2 equivalent of bulk HFCs that producers and importers may place on the market each year. Companies must be registered and hold sufficient quota before such bulk supply can lawfully take place.

Question 40F-gas and ODS regulations, legal duties and environmental impact

From 1 January 2017, new cars could only be placed on the market if their mobile air-conditioning system used a refrigerant with what maximum GWP?

  1. 750 or less
  2. 150 or less Correct answer.
  3. Zero
  4. 75 or less

Explanation

Mobile air-conditioning in new vehicles has been restricted to refrigerants with a GWP of no more than 150 since 1 January 2017. This is why R-134a, with a GWP of 1430, was replaced by R-1234yf in new car platforms.

Question 41Refrigerant safety, cylinder handling, PPE and risk assessment

Which type of glove is appropriate when handling refrigerant cylinders and making connections?

  1. Low-temperature insulating gloves Correct answer.
  2. Heavy duty leather rigging gloves
  3. General purpose cotton handling gloves
  4. Disposable nitrile examination gloves

Explanation

Liquid refrigerant boils at a very low temperature, so contact with skin, a cold valve or escaping liquid can cause cryogenic burns. Gloves designed for low-temperature work provide thermal insulation while remaining flexible enough to handle valves and gauges.

Question 42Refrigerant safety, cylinder handling, PPE and risk assessment

What eye protection should be worn where there is a risk of liquid refrigerant spraying during a task?

  1. Tinted welding goggles
  2. Standard safety spectacles with side shields
  3. Chemical splash goggles and a face shield Correct answer.
  4. Prescription glasses on their own

Explanation

A refrigerant splash can cause severe cold burns to the eye and surrounding skin. Goggles seal around the eye to stop liquid reaching it, and a face shield protects the rest of the face from a sudden release.

Question 43Refrigerant safety, cylinder handling, PPE and risk assessment

How should refrigerant cylinders be kept in a workshop?

  1. Laid horizontally on racking to save space
  2. In a sealed cupboard to keep them dry
  3. Upright, secured, in a well ventilated area Correct answer.
  4. Stacked no more than three high on the floor

Explanation

Cylinders are stored upright so that the valve stays at the top and liquid cannot enter the valve or regulator. They must be restrained to prevent falling and kept in a ventilated place so any leakage disperses rather than accumulating.

Question 44Refrigerant safety, cylinder handling, PPE and risk assessment

What is the purpose of the valve protection cap fitted to a refrigerant cylinder?

  1. It shields the valve from impact damage Correct answer.
  2. It seals the valve thread to prevent leaks
  3. It shows the cylinder has been inspected
  4. It allows the cylinder to be lifted by crane

Explanation

The cap is a mechanical guard, not a pressure seal. If a cylinder falls, an unguarded valve can be sheared off and release the full charge violently, so the cap must be in place whenever the cylinder is in storage or transit.

Question 45Refrigerant safety, cylinder handling, PPE and risk assessment

Why is refrigerant vapour a particular hazard in low-lying areas such as pits and basements?

  1. It rises quickly and collects at ceiling level
  2. It reacts with concrete to form a toxic gas
  3. It is lighter than air and disperses slowly
  4. It is heavier than air and can accumulate Correct answer.

Explanation

Most refrigerant vapours are denser than air, so they sink and pool in the lowest part of a space. In a basement or pit this can produce an oxygen-deficient atmosphere at the exact place where an engineer is working.

Question 46Refrigerant safety, cylinder handling, PPE and risk assessment

What is the correct first aid for skin that has been splashed with liquid refrigerant?

  1. Flush with lukewarm water and get medical help Correct answer.
  2. Apply a hot compress and cover with a dressing
  3. Wash with solvent then apply a sterile dressing
  4. Rub the area briskly to restore circulation

Explanation

Liquid refrigerant causes cold burns by freezing tissue, so the affected area should be flushed gently with lukewarm water to rewarm it slowly. Rubbing damages frozen tissue, and medical assessment is needed because the depth of a cold burn is not always obvious at first.

Question 47Refrigerant safety, cylinder handling, PPE and risk assessment

What is the main purpose of a risk assessment for a refrigerant task?

  1. To identify hazards and decide on controls Correct answer.
  2. To show that the work can be completed quickly
  3. To provide a written record for the client file
  4. To confirm that the engineer holds a qualification

Explanation

A risk assessment is a structured look at what could cause harm and how likely that is, followed by a decision on the controls needed. The written record exists to communicate and review those decisions, not to satisfy paperwork.

Question 48Refrigerant safety, cylinder handling, PPE and risk assessment

Which document should be consulted first for hazard, first aid and handling information on a particular refrigerant?

  1. The refrigerant pressure-enthalpy chart
  2. The cylinder test certificate
  3. The manufacturer's safety data sheet Correct answer.
  4. The site emergency evacuation plan

Explanation

The safety data sheet is the supplier's formal summary of the hazards of the substance, together with first aid, handling, storage and exposure information. It should be available before the refrigerant is used and kept where workers can reach it.

Question 49Refrigerant safety, cylinder handling, PPE and risk assessment

When recovering liquid refrigerant into a recovery cylinder, what is the maximum fill level by weight?

  1. 80% of its capacity by weight Correct answer.
  2. 50% of its capacity by weight
  3. 95% of its capacity by weight
  4. 100% of its capacity by weight

Explanation

Liquid refrigerant expands as it warms, so a cylinder filled to capacity could become hydraulically full and rupture. Filling to about 80% leaves an ullage space for expansion, and the cylinder must be weighed during filling.

Question 50Refrigerant safety, cylinder handling, PPE and risk assessment

Which practice is acceptable when a refrigerant cylinder needs to be warmed to speed up transfer?

  1. Placing it beside a space heater running at full output
  2. Wrapping it in an unregulated heat mat
  3. Playing a blowtorch over the cylinder base
  4. Using a warm water bath at a controlled temperature Correct answer.

Explanation

Warming raises the cylinder pressure, but the heat must be gentle and controlled. A warm water bath with a thermometer keeps the cylinder within its permitted temperature, while flames and uncontrolled heaters can overpressure it.