All systems must be designed so that they are able to be:

• manufactured
• installed
• operated
• maintained
• decommissioned,

without the loss of refrigerant.

The system design must comply with Clauses 2.2 to 2.9 of this code.

Where the designer can provide evidence that a system has been designed to an equivalent or better standard than is set out in this section, and complies with this clause, the design may be considered exempt from Clauses 2.3 to 2.9 inclusive.

Good system design is necessary for the prevention of refrigerant leakage.

All systems must be designed in accordance with the applicable Australian and New Zealand standards. These standards set minimum compliance requirements to ensure all potential hazards are eliminated or reduced to an acceptable level.

Refrigerating appliances or systems must also adhere to the following product standards as applicable:

• AS/NZS 60335.1 – Household and Similar Electrical Appliances – Safety – General requirements
• AS/NZS 60335.2.11 – Particular requirements for tumble dryers
• AS/NZS 60335.2.24 – Particular requirements for refrigerating appliances, ice cream appliances and ice makers
• AS/NZS 60335.2.34 – Particular requirements for motor compressors
• AS/NZS 60335.2.40 – Particular requirements for electrical heat pumps, air conditioners and dehumidifiers
• AS/NZS 60335.2.75 – Particular requirements for commercial dispensing appliances and vending machines
• AS/NZS 60335.2.89 – Particular requirements for commercial refrigerating appliances with an incorporated or remote refrigerant condensing unit or compressor

Appliances that meet these standards are considered to comply with AS/NZS 5149.2 with the exception of electrical heat pumps, air conditioners and dehumidifiers. For these appliances, AS/NZS 60335.2.40 mandates that they also adhere to the mechanical strength requirements outlined in AS/NZS 5149.2.

Ensuring proper initial installation and adhering to a thorough maintenance program should minimise leaks associated with compressors in self-contained low charge systems, which are typically from the internal connecting pipework.

Given the small amount of refrigerant contained in them, these sealed systems are not generally provided with service valves.

Pressure relief arrangements in self-contained low charge systems must be designed in accordance with the applicable appliance standard, AS/NZS 5149.2 or AS/NZS 1200, which specifies the type and size of pressure relieving device permitted for different system types.

Due to the size of self-contained low charge systems, liquid receivers used for pump down are not normally included in the design.

For these applications, one of the following two options must be undertaken:

1. Valves fitted to the system to allow the connection of a recovery unit for the removal of refrigerant prior to service or repair operations.
2. A process tube can be used for this purpose with the addition of a temporary clamp-on piercing type valve.

All supervisory personnel involved in the manufacturing process must be conversant with refrigerant technology and familiar with all aspects of the manufacturing process.

Complete systems must be supplied clean, dry, leak tightness tested, evacuated, pressurised, sealed and labelled with the refrigerant type before delivery.

If the system is pressurised with a substance other than the specified refrigerant, this substance must be identified on the system label.

All manufactured systems and components must be factory tested for leak tightness in accordance with the applicable manufacturing standard or must be pressure tested to the required pressure level in accordance with AS/NZS 5149.2 or AS 4041.

All refrigerant-containing parts, units or systems must be tested and proved tight by the manufacturer at not less than the design pressure for which they are rated.

All systems must be evacuated prior to charging with refrigerant.

All systems should be evacuated to less than 500 microns/67Pa absolute pressure before charging with refrigerant.

All charging must be carried out in accordance AS/NZS 5149.4, with the exception that manufacturers are not required to charge solely into the low-pressure side of the system.

The manufacturer or installer must supply an adequate number of instruction manuals and also provide safety instructions.

The systems covered by this code are self-contained products that are manufactured and sold as completed units. As no work on the refrigeration system is required on site, installation is normally the responsibility of the purchaser. The manufacturer’s installation instructions should be followed.

The manufacturer’s instructions for commissioning should be followed. Manufacturer’s instructions must not specify a practice that will result in emission of scheduled refrigerant.

Appliances that are manufactured, assembled and tested prior to being delivered to site must be provided with installation, operation and maintenance instructions in accordance with Section 3.

Manufacturer’s instructions must not specify a practice that will result in emission of scheduled refrigerant.

A clearly readable identification plate must be located on the appliance. The identification plate must contain at least the following data:

• the name or identification of the supplier or manufacturer
• the model, serial number, or reference number
• the year of manufacture

Note: The year of manufacture can be part of the serial number, and all information can be part of the identification plate of the equipment and can be coded.

• the number designation of the installed refrigerant in accordance with AS/NZS ISO 817
• the refrigerant charge
• the maximum allowable pressure, high- and low-pressure sides
• when flammable refrigerants are used, the flame symbol (ISO 7010 W021).

Whenever the type of refrigerantand/or lubricant in a system is changed, see Section 10, the technician must clearly label the system with:

• the number designation of the new replacement refrigerant in accordance with AS/NZS ISO 817
• the refrigerant charge
• the maximum allowable pressure, high- and low-pressure sides
• when flammable refrigerants are used, the flame symbol
• name of technician, licence number (Australia only) and service organisation
• date of change
• whether any ultraviolet dye has been added.

Whenever the type of lubricant in a system is changed (other than when it has been pre-charged into a replacement compressor by its manufacturer), the service technician must also clearly label the system with:

• the lubricant type.

Systems must be evacuated prior to system recharging, every time the refrigerant is removed from the system, e.g. during repair or replacement.

Manufacturers’ evacuation instructions must not specify a practice that will result in emission of scheduled refrigerant.

Manufacturers’ instructions should be followed if the system manufacturer has supplied instructions for evacuation.

If the manufacturers’ instructions are followed, the evacuation procedure is exempt from the requirements of this section.

The relevant parts of this section of this code must be complied with if there are any evacuation procedures not covered by the manufacturer’s instructions.

Evacuation of all other systems, or systems where the manufacturers’ instructions are not supplied, must comply with this section of this code in its entirety.

Evacuation should be carried out with dedicated evacuation hoses (large diameter/as short as practical) and vacuum gauges and not service manifolds/gauges.

Depth of vacuums must be measured using accurate measuring equipment selected for the specific application, i.e. a dedicated vacuum gauge, not a standard manifold pressure gauge.

Scheduled refrigerants must be recovered from the system prior to evacuation. Before beginning the evacuation process the system must be completely depressurised, ensuring that air is not introduced into the pipework.

Procedures must be planned so breaking the vacuum with refrigerant does not introduce contaminants into the system.

If the system manufacturer has not supplied instructions with the system for evacuation, the system must be evacuated to below 500 microns/67Pa absolute.

Note: When evacuating a wet system in ambient temperatures below 0°C, it will take a lot longer for the system dehydration to be achieved. If a wet system has a vacuum pulled below 4,500 microns, some of the internal moisture can change to solid ice. Where possible, warm the equipment up. Do not use flame-based methods.

After the system has been evacuated, the vacuum pump mustbe isolated from the system to check if the system vacuum pressure rises. This is known as the ‘drop test’.

As a guide, with constant ambient conditions, the vacuum should not rise more than 100 microns (13.33Pa absolute) in one hour. A greater rate of rise during the drop test may indicate a leak or the presence of moisture, and the system must be leak tightness tested and all leaks repaired.

All refrigerant containing pipework and components must be evacuated before refrigerant charging.

The system refrigerant charge limits for any appliance must not be exceeded, see Clause 2.3.

All charging must be carried out in accordance with AS/NZS 5149.4, SectionC.2 Handling. Note that pure refrigerants can be charged as a vapour or liquid but refrigerant blends can only be charged as a liquid.

Hoses, fittings and procedures used during charging must be those which minimise the loss of refrigerant.

The hoses connecting a cylinder to a self-contained low charge system must be leak-tested before the cylinder valve is fully opened. This can be done by partially opening and then closing the cylinder valve to pressurise the connecting hoses and testing for a leak.

Refrigerant must be weighed into and weighed out of the system.

Refrigerant being transferred must be accurately measured into the system with due reference to temperature in accordance with AS 4211.3.

The refrigerating system must not be overfilled.

Charging lines should be as short as possible and have suitable fittings to minimise losses during disconnection at the end of the transfer.

Care should be taken to avoid refrigerant liquid being trapped between closed valves, as high pressures may develop.

Refrigerant cylinders must not be connected to a system at a higher pressure, or to a hydraulic leg, where the pressure is sufficient to cause a back flow of refrigerant into the cylinder.

Refrigerant cylinders must not be connected to systems or other cylinders at a higher temperature for similar reasons.

Back flow of refrigerant can result in cylinders being contaminated or overfilled, resulting in the subsequent danger from the development of a pressure high enough to burst the cylinder.

Before charging a refrigerating system with a flammable refrigerant, it is essential to ensure that the immediate area (deemed a temporary flammable zone) is suitable for working safely and the appropriate precautions are in place. This should include an assessment of the area for ventilation, sources of ignition, fire hazards, fire safety equipment and include the use of detection equipment and personal protective equipment (PPE).

Refer to the AIRAH Flammable Refrigerants Safety Guide for further details on temporary flammable zones.

The refrigerating system must be earthed prior to charging with flammable refrigerant.

Technicians handling equipment containing a scheduled refrigerant must be competent (i.e. suitably qualified and holding a relevant national licence where required, see definition in Appendix C).

Scheduled refrigerant must not be discharged to atmosphere. All scheduled refrigerants must be recovered and either recycled, reclaimed, or held for destruction in an approved manner.

If the technician doubts the integrity of the system, it must not be recharged until appropriate repairs and leak testing have been undertaken.

Having identified and located a leak, all remaining refrigerant must be recovered to a separate cylinder, if isolation is impractical, after which the repair can be undertaken.

The cylinders designated for the recovery of scheduled refrigerants should not be used for recovery of any other refrigerants. Technicians should always read and understand the instructions and advice of the manufacturers and suppliers of all equipment, and apply as relevant and appropriate.

A technician should be aware of the possibility that the system may have been incorrectly charged or incorrectly labelled.

Before working on an unfamiliar system, the technician should first establish the type of refrigerantcontained in the system by checking the pressure/temperature relationship or by using a refrigerant analyser or other methods, to verify that the labelling is correct.

Any refrigerantthat cannot be identified must not be vented from the system.

If identification of the refrigerant is not possible it should be treated as a flammable refrigerant.

When working on appliances containing flammable scheduled refrigerant, instructions conforming to the requirements of AS/NZS 60335.2.40: Annex DD must be adhered to.

Manufacturers and suppliers include additional safety information in the operation and maintenance manuals for equipment using a flammable refrigerant. Technicians should always read and understand the instructions and advice of the manufacturers and suppliers of all equipment, and apply as relevant and appropriate.

Tools and equipment must be rated for use with the appropriate flammability grade (2 or 2L).

For flammable refrigerants, if a leak is suspected, all sources of ignition and naked flames must be removed/extinguished.

Before beginning work on systems containing flammable refrigerants, safety checks are necessary to ensure that the risk of ignition is minimised. Ensure that the area is in the open or that it is adequately ventilated before breaking into the system or conducting any hot work. Any mechanical ventilation utilised should be suitable for use in a potentially hazardous environment. Electrical devices, leads or ignition sources in the vicinity should not be energised, unless rated for hazardous environments.

For more information, refer to the flammable refrigerant resources mentioned in the Preface of this code.

Including in-service leak inspections as part of a preventative maintenance program allows the technician to find and fix small leaks before they lead to complete loss of refrigerant charge.

The in-service leak inspection is carried out with the refrigerant in place and the appliance operating as normal.

‘Inspected for leakage’ means the equipment or system is examined primarily for leakage using direct or indirect measuring methods, focusing on those parts of the equipment or system most likely to leak.

The technician should check, and repair as necessary, all potential leak sites.

Replacement of components or changes to the refrigerating system should be ordered and carried out by a competent person.

System components should be replaced with parts that are more leak resistant or have a reduced number of potential leak sources.

An equivalent replacement ‘O’ ring seal should be used each time an 'O’ ring connection is remade.

This procedure covers cleaning and flushing a contaminated system after a hermetic or semi-hermetic compressor failure or motor burnout.

Where possible, self-contained low charge systems should be taken to a workshop with appropriate facilities for cleaning and reinstating. When the system is empty and at atmospheric pressure, the faulty component parts should be removed and the system capped off.

The system must not be recharged before the system has been fully leak tested, all identified leaks repaired and the system has been evacuated in accordance with Section 6.

Refrigerant used to recharge a system must meet the specification for new refrigerant set out by AHRI 700.

Because most lubricants are very hygroscopic and will absorb moisture from the air, they should not be exposed to atmosphere for any longer than is necessary.

The system should be recharged to the refrigerant quantity shown on the identification plate.

The owner of a refrigerating appliance is responsible for its use and care.

A malfunctioning unit should be attended to by a competent service technician as soon as the condition occurs to ensure that any leakage of refrigerant is minimised.

All scheduled refrigerants must be recovered and either recycled, reclaimed, or sent for destruction in an approved manner.

The appliance must not be recharged before the system has been fully leak tightness tested and all identified leaks repaired.

Scheduled refrigerant must never be deliberately vented or leaked from a refrigerating system.

Owners and operators of refrigerating appliances in Australia are advised that licenced service technicians are required by legislation to observe this code of practice. A system known to be leaking must not be topped up with refrigerant until all leaks are fixed. A technician must not do other work on leaking equipment without repairing the leak.

Some modification to appliances may be necessary to avoid leaks and achieve the aim of the code of practice to minimise loss of refrigerant.

p>To keep a system operating efficiently and effectively, and reduce the chance of major breakdown, it is in the interest of the operator to properly maintain the system by following the operating and maintenance instructions from the manufacturer, ensuring the appliance is regularly maintained and accepting the necessary repairs and adjustments proposed by the service technician.

It is recommended that a routine maintenance agreement for the appliance be undertaken with a competent service technician.

All users should monitor the operation of their installation and call the service technician immediately if any abnormal condition is found. Apart from minimising the loss of refrigerantto the atmosphere this may also save the cost of an expensive repair or replacement and ensure the ongoing efficient operation of the system.

Under Australian regulations, systems must not be charged with a higher global warming potential (GWP) refrigerant than the equipment was designed to use. See Clause 1.2.2 for more detail.

p>The procedures specified in AS/NZS 5149.4 Change of refrigerant type must be followed when a refrigerant change is to be carried out.

Guidance on equipment suitability for refrigerant type change should be sought from the original equipment manufacturer, new refrigerant manufacturer and lubricant manufacturer.

The system should not be changed to a replacement refrigerant with a more hazardous AS/‌NZS 817 Safety Group Classification (see Appendix B) unless:

• The system has been re-engineered by a competent refrigeration or air conditioning engineer.
• The required changes to the system have been designed in accordance with the applicable compliance standard and carried out and documented, in accordance with AS/NZS 5149.4.
• Any introduced flammability concerns have been addressed in accordance with AS/NZS 5149 and AS/NZS 3000.
• The system complies with other relevant standards such as those relating to electrical and gas safety.

The person changing a refrigerant to a more hazardous refrigerant takes on a role similar to that of a designer of a refrigeration system. Where a different classification of refrigerant is being considered (e.g. changing from A1 to A2, A2L, or A3), a system conversion process is required.

Refer to the Heads of Workplace Safety Authorities (HWSA) Flammable Refrigerant Gases Position Paper and the AIRAH Flammable Refrigerants Safety Guide for more details on the system conversion process for flammable refrigerants.

The replacement refrigerant must be compatible with all parts of the system it is in contact with. This includes the lubricant, seals and all other wetted components.

A new filter dryer appropriate for the replacement refrigerant must be fitted.

Refrigerating systems modified on site must be labelled, in accordance with Clause 5.2.

When a system refrigerant has been changed, the system’s labelling, colour coding (if applicable) and nameplates must be changed to permanently identify the replacement refrigerant now contained in the system.

System operation and maintenance documentation must be updated.

Refrigerant cylinders will often be used as temporary receivers for all or part of the refrigerant charge. Hazards can arise in the use of refrigerant cylinders in this way and the requirements of this section must be complied with.

Warning: Non-condensable gases mixed with refrigerant can be extremely hazardous, increasing the pressure above normal vapour pressure. They can cause a cylinder to burst during filling or warming.

Flammable refrigerants must be recovered using equipment rated for use with the appropriate flammability grade (2, 2L or 3). Refrigerant cylinders used must be designed for the refrigerant in use.

In Australia, it is an offence to act in a way that results in the unlawful discharge of scheduled refrigerants. Recovery and disposal of refrigerant at the end of its useful life using appropriate recovery equipment or recovery/recycling equipment is mandatory. Any person who handles a scheduled refrigerant must hold a Refrigerant Handling Licence.

In New Zealand, it is an offence under the Ozone Layer Protection Act 1996 to wilfully release an ozone-depleting substance. It is also illegal to release synthetic greenhouse gases into the atmosphere under the Climate Change Response Act (CCRA) 2022.

In New Zealand, any person refilling a cylinder must hold a current Refrigerant Fillers Certificate relevant to the refrigerant involved.

To avoid mixing refrigerants that can be recycled or reused it is necessary to use dedicated recovery equipment for each refrigerant type being recovered.

To ensure that no recovery cylinder is over-filled, it is necessary to ensure that only cylinders marked with the correct filling ratio are used, and that this filling ratio is not exceeded for the refrigerant or mixture being reclaimed.

In Australia all scheduled refrigerant being removed from equipment must be recovered and either recycled, reclaimed or disposed of, in accordance with this section.

Scheduled refrigerants must be recovered into an appropriately labelled cylinder of suitable pressure rating for the refrigerant being recovered. Refrigerant must not be recovered into a flexible bag.

The entire refrigerant charge, refrigerant vapour as well as refrigerant liquid, must be recovered when a system is emptied.

Recycled refrigerant is refrigerant that is re-used, with or without some cleaning taking place.

Reclaimed refrigerant is refrigerant that is re-used after it has been reprocessed to meet the AHRI 700 specification.

The use of recycled refrigerant that has not been cleaned can be detrimental to a refrigerating system. Recovered refrigerant can contain moisture, oils, acidity, particulates and non-condensable gases. Re-using this refrigerant without cleaning may cause corrosion to copper and aluminium components, shortening the life of heat transfer coils and compressors.

Analysis of the recycled refrigerant to ensure it is fit for use should be undertaken prior to re-use.

Contaminated recycled refrigerant should be reclaimed prior to re-use.

Recovered refrigerant should be reclaimed before being used in a different system. Using recovered refrigerant that has not been reclaimed may void equipment warranty and seriously damage the system.

The importation and storage of scheduled refrigerant in disposable (non-refillable) refrigerant containersis prohibited by law in Australia. The following requirements apply to New Zealand only:

1. Any residual refrigerantin a disposable container must be recovered
2. A disposable container must not be refilled or used as a temporary receiver during service
3. A disposable container must not be repaired or modified in any way
4. Empty disposable containers must be disposed of at a recycling centre.

Under Australian WHS/OHS regulations, and New Zealand Hazardous Substances and New Organisms Act 1996 (HSNO), hazardous chemicals including refrigerants are classified according to the Globally Harmonised System for the Classification and Labelling of Chemicals (GHS).

The GHS is designed to provide information for the safe storage, handling and use of a hazardous chemical. This system is independent of the refrigerant classifications of AS/NZS ISO 817.

A refrigerant is required to have a Safety Data Sheet (SDS) developed and supplied by the manufacturer or importer which describes the hazard classification/s. The SDS provides the chemical hazard information on a product which is used as a basis for safely managing the related storage, and handling risks. Asphyxiation and freeze burns are also a risk.

Refrigerant SDS should be readily available and personnel should refer to the SDS before handling refrigerants.

For flammable scheduled refrigerants, technicians must take the relevant safety measures for the correct transport, storage, and handling of a flammable gas.

This includes ensuring that the refrigerant is not exposed to open flames or other ignition sources. Toxic substances like hydrogen fluoride and carbon monoxide are created when fluorinated refrigerants are burnt.

For additional information on flammability hazards refer to resources such as those listed in the Preface of this code.

Losses of refrigerant to the atmosphere can occur during the handling and storage of refrigerant cylinders. Competent technicians can minimise such losses.

Where a scheduled refrigerant is to be transferred to a charging station, refrigerant vapour vented to atmosphere must be minimised.

The provisions of Clause 12.4 also apply to refrigerant transfer between cylinders.

Where refrigerant is to be transferred from one cylinder to another, a pressure or height difference must be established between the cylinders and this may be achieved by means of a pump or temperature differential.

Refrigerant cylinders should not be manifolded together if there is a possibility of temperature differences between the cylinders, since this will result in refrigerant transfer and the danger of overfilling the cold cylinder.

Where cylinders are manifolded together:

• Care should be taken to ensure all the cylinders are at the same height to avoid gravity transfer between cylinders.
• It is recommended that single direction flow or check valves be installed at each cylinder.

Refrigerants are classified into safety groups according to the criteria of AS/NZS ISO 817.

The safety classifications consist of two alphanumeric characters (e.g. A2 or B1). The capital letter indicates the toxicity and the numeral denotes the flammability.

Refrigerants are assigned to one of two classes, A or B, based on the following exposure:

• Class A (lower chronic toxicity) signifies refrigerants that have an occupational exposure limit of 400ppm or greater,
• Class B (higher chronic toxicity) signifies refrigerants that have an occupational exposure limit of less than 400ppm.

Refrigerants are assigned to one of four classes based on flammability: 1, 2L, 2 or 3.

Class 1 (no flame propagation)

Single compound refrigerants or refrigerant blends that do not exhibit flame propagation when tested in air at 60°C and 101.3kPa.

Examples: R22, R134a, R404A. R410A, R744.

Class 2L (lower flammability)

Single compound refrigerants or refrigerant blends that meet all of the following conditions:

• exhibit flame propagation when tested at 60°C and 101.3kPa
• have a lower flammability limit (LFL) ≥ 3.5% by volume
• have a heat of combustion < 19,000kJ/kg
• have a maximum burning velocity of < 10cm/s when tested at 23°C and 101.3kPa.

Examples: R32, R1234yf, R1234ze, R717.

Class 2 (flammable)

Single compound refrigerants or refrigerant blends that meet all of the following conditions:

• exhibit flame propagation when tested at 60°C and 101.3kPa
• have an LFL ≥ 3.5% by volume
• have a heat of combustion < 19,000kJ/kg.

Examples: R152a, R439A.

Class 3 (higher flammability)

Single compound refrigerants or refrigerant blends that meet the following conditions:

• exhibit flame propagation when tested at 60°C and 101.3kPa
• have an LFL < 3.5% by volume
• have a heat of combustion that is ≥ 19,000kJ/kg.

Examples: R290, R600, R601, R1270.

Blends whose flammability and/or toxicity characteristic may change as the composition changes during fractionation are assigned a dual safety group classification, with the two classifications separated by a slash (/).

Each of the two classifications has been determined according to the same criteria as a single component refrigerant.

• The first classification listed is the classification of the ‘as formulated’ composition of the blend.
• The second classification is the classification of the blend composition of the ‘worst case fractionation’.

For flammability, ‘worst case of fractionation’ is defined as the composition during fractionation that results in the highest concentration of the flammable component(s) in the vapour or liquid phase.

For toxicity, ‘worst case of fractionation’ is defined as the composition during fractionation that results in the highest concentration(s) in the vapour or liquid phase for which the Threshold Limit Value – Time Weighted Average (TLV-TWA) is less than 400ppm. The TLV-TWA for a specified blend composition has been calculated from the TLV-TWA of the individual components.

The Australian Code for the Transport of Dangerous Goods by Road and Rail (ADG Code), available online at www.ntc.gov.au, provides detailed technical specifications and recommendations applicable to the transport of dangerous goods in Australia by road and rail including refrigerants.

The ADG Code covers the requirements for classification, packaging, marking and labelling of substances and articles that meet the United Nations classification criteria for dangerous goods.

ADG Class 2 substances are assigned to one of three divisions based on the primary hazard of the gas during transport. These divisions are designated:

• Division 2.1 Flammable gases,
• Division 2.2 Non-flammable, non-toxic gases
• Division 2.3 Toxic gases.

Division 2.1 Flammable gases

Division 2.1 Flammable gases are gases which at 20°C and a standard pressure of 101.3kPa:

• are ignitable when in a mixture of 13% or less by volume with air, or
• have a flammable range with air of at least 12 percentage points regardless of the lower flammable limit. Flammability should be determined by tests or by calculation in accordance with methods adopted by ISO (see ISO 10156). Where insufficient data are available to use these methods, tests by a comparable method recognised by the relevant authority may be used.

Examples: R32, R143A, R600, R1270.

Division 2.2 Non-flammable, non-toxic gases

Division 2.2 Non-flammable, non-toxic gases are gases which:

• are asphyxiant – gases that dilute or replace the oxygen normally in the atmosphere, or
• are oxidising – gases that may, generally by providing oxygen, cause or contribute to the combustion of other material more than air does, or
• do not come under the other divisions.

Examples: R22, R134a, R404A, R407A, R410A, R744 (carbon dioxide).

Division 2.3 Toxic gases

Division 2.3 Toxic gases are gases which:

• are known to be so toxic or corrosive to humans as to pose a hazard to health, or
• are presumed to be toxic or corrosive to humans because they have an LC₅₀ value equal to or less than 5,000ml/m³ (ppm).

Example: R717 (ammonia).

Class 2L, 2 and 3 flammable refrigerants (under AS/NZS ISO 817) are flammable when mixed with air (oxygen) at a percentage range specific to each refrigerant.

The lower flammability limit (LFL)is the minimum concentration of the refrigerant that can propagate a flame through a homogeneous mixture of the refrigerant and air under the specified test conditions at 23°C and 101.3kPa. That is, the mixture capable of producing a flame.

For example, R32 is flammable when mixed with air (or oxygen) at a certain percentage and ignited. The quantity of R32 vapour required to make the mixture flammable sits within a narrow band of 14.4% to 29%, see the diagram below. The LFL of 14.4% for R32 is equivalent to 307g/m³.

R32 lower flammability limit

Referring to the figure above, if there is less than 14.4% of R32 in the air then there is insufficient fuel (the R32) for combustion. If there is more than 29% then there is insufficient oxygen (air) for combustion. When the mixture is within these concentrations it is said to be in its 'flammable region'.

The bottom of this region is called the 'lower flammability limit' (LFL) and minimum design standards attempt to ensure that the LFL of the refrigerant cannot be reached if there is a leak. Note that these percentage values may also be expressed in kg/m³ or g/m³.

For the purpose of this code the following definitions apply:

Blend

A combination of two or more refrigerantsin a defined ratio which form a refrigerantwith specified thermodynamic properties and a refrigerant R number designation.

Compatible

Components having features and composition that do not significantly degrade longevity or functionality of the composite system.

Competent

A person who has acquired, through training, qualifications, experience or a combination of these, the knowledge and skill, and where relevant the applicable licence, enabling the person to safely perform the assigned work

Contaminated refrigerant

A refrigerantcontaining oil, acid, non-condensable substances and/or moisture and/or other foreign substances. This could include mixed refrigerants(cocktails) which are not a manufactured product.

Cylinder

A portable storage vessel designed for the safe storage and handling of refrigerantunder pressure.

Decommissioning

The process whereby a system is deliberately rendered inoperable, including the removal and recovery of any scheduled refrigerant.

Destruction

A process whereby a refrigerant is permanently transformed or decomposed into other substances.

Disposable container, disposable refrigerant container

A non-refillable cylinder.

Flammable refrigerant

A refrigerant with a flammability classification of Class 2L, Class 2 or Class 3 in accordance with AS/NZS ISO 817.

Flammable scheduled refrigerant

A flammable refrigerant that is also listed under Schedule 1 of the Ozone Protection and Synthetic Greenhouse Gas Management Act 1989, (see Appendix A).

Fluorocarbon

A hydrocarbon in which some or all of the hydrogen atoms have been replaced by fluorine.

Global warming potential (GWP)

The atmospheric warming impact of a refrigerant compared with an equal mass of carbon dioxide over a specified period of time (usually 100 years).

Heat pump

A piece of equipment capable of using ambient or waste heat from air, water or ground sources to provide heat or cooling and is based on the interconnection of one or more components forming a closed cooling circuit in which a refrigerant circulates to extract and release heat.

Major components and sub-assemblies

Equipment including compressors, air/water cooled condensers, liquid receivers, chilled water heat exchangers, evaporators and air/water cooled condensing units.

Maximum allowable pressure (PS)

Maximum pressure which system or component is designed for, as specified by the manufacturer in accordance with AS/NZS 5149.2.

Must

When used for a provision, indicates that the provision is mandatory for compliance with this code.

Ozone depletion potential (ODP)

The capacity of a refrigerant to destroy stratospheric ozone. ODP is stated relative to the ODP of CFC-11, which is taken as having an ODP of 1.

Plant

A combination of one or more refrigerating systems at a single site.

Reclaim

To reprocess used refrigerant to new product specification by means that may include distillation. Chemical analysis of the refrigerant is required to determine that appropriate product specifications have been met. This term usually implies the use of processes or procedures available only at a specialised reclaim or manufacturing facility.

Recover, recovery

To remove refrigerant in any condition from a system and store it in an external cylinder, without necessarily testing or processing it in any way.

Refrigerant

The medium used for heat transfer in a refrigerating system, which absorbs heat on evaporating at a low temperature and a low pressure and rejects heat on condensing at a higher temperature and higher pressure. The term ‘gas’ should be avoided when referring to refrigerants. Unless specified otherwise, ‘refrigerant’ in this code refers to scheduled refrigerants only.

Refrigerating system

An assembly of piping, vessels, and other components in a closed circuit in which a refrigerant is circulated for the purpose of transferring heat.

RAC equipment (refrigeration and air conditioning equipment)

Equipment used for the cooling or heating of anything, and that uses a scheduled refrigerant.

Retrofit

To replace the original refrigerant(and components, lubricant, etc. as required) in a system with an alternative.

Returned refrigerant

Refrigerant recovered from a system and returned to the supplier or equivalent for reclaim or destruction.

Scheduled refrigerant

A refrigerant with an Ozone Depletion Potential and/or a Global Warming Potential that is listed under Schedule 1 of the Ozone Protection and Synthetic Greenhouse Gas Management Act 1989, (see Appendix A). Generally synthetic chemicals consisting of or containing fluorocarbon, which include chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFC), but not hydrofluoroolefins (HFO).

Self-contained low charge systems

Appliances that contain a refrigerant charge of 2kg or less, and do not require any work to be done on the refrigerating system at the time of installation.

Should, recommended

Indicate provisions that are not mandatory for compliance with this code but which are desirable as good and best practice.

Split systems

Systems that require interconnecting pipework and electrical connections between the separate evaporator unit and the condensing unit. Note that split systems fall outside the scope of this code. Refer instead to the Australia and New Zealand refrigerant handling code of practice Part 2 – Systems other than self-contained low charge systems.

For definitions of other components, refer to AS/NZS 5149.1, Section 3: Terms and definitions.

Acronyms and abbreviations for standards organisations and relevant websites

Other acronyms and initialisms used in this code have the following meaning:

GWP Global warming potential

IPCC Intergovernmental Panel on Climate Change

LFL Lower flammability limit

ODP Ozone depletion potential

OFN Oxygen free nitrogen

OHS Occupational Health and Safety

PPE Personal protective equipment

RAC Refrigeration and air conditioning

RCL Refrigerant charge limit

SDS Safety Data Sheets

SFC Safe fill capacity

WHS Work Health and Safety

Australia

• Ozone Protection and Synthetic Greenhouse Gas Management Act 1989
• Ozone Protection and Synthetic Greenhouse Gas Management Regulations 1995
• Australia and New Zealand Refrigerant Handling Code of Practice Part 2 – Systems other than self-contained low charge systems
• Australian automotive code of practice for the control of refrigerant gases during manufacture, installation, servicing or de-commissioning of motor vehicle air conditioners
• Australian Code for the Transport of Dangerous Goods by Road and Rail
• Heads of Workplace Safety Authorities: Flammable Refrigerant Gases Position Paper.

New Zealand

• Ozone Layer Protection Act 1996
• Climate Change Response (Zero Carbon) Amendment Act 2019
• Hazardous Substances and New Organisms Act 1996
• NZ Approved Code of Practice – Pressure Equipment (excluding Boilers).
• Guide to gas cylinders – Worksafe NZ
• Land Transport Rule: Dangerous Goods 2005 (NZ)

AS/NZS ISO 817 Refrigerants – Designation and safety classification

AS/NZS 1200 Pressure Equipment

AS 2030.1 Gas cylinders. Part 1: General requirements

AS 2030.5 Gas cylinders. Part 5: Filling, inspection and testing of refillable cylinders

AS/NZS 3000 Electrical installations (known as the Australian/New Zealand Wiring Rules)

AS 4211.3 Gas recovery on combined recovery and recycling equipment. Part 3: Fluorocarbon refrigerants from commercial/domestic refrigeration and air conditioning systems

AS/NZS 4332 Storage of gases in cylinders

AS 4484 Gas cylinders for industrial, scientific, medical and refrigerant use – Labelling and colour coding

AS/NZS 5149 Refrigerating systems and heat pumps – Safety and environmental requirements

AS/NZS 5149.1 – Part 1: Definitions, classification and selection criteria (ISO 5149-1:2014, MOD) (incorporating Amd 1 and Amd 2)

AS/NZS 5149.2 – Part 2: Design, construction, testing, marking and documentation (ISO 5149-2:2014, MOD)

AS/NZS 5149.4 – Part 4: Operation, maintenance, repair and recovery (ISO 5149-4:2014, MOD)

AS/NZS 60335.1 Household and Similar Electrical Appliances – Safety – General requirements

AS/NZS 60335.2.11 Particular requirements for tumble dryers

AS/NZS 60335.2.24 Particular requirements for refrigerating appliances, ice cream appliances and ice makers

AS/NZS 60335.2.34 Particular requirements for motor compressors

AS/NZS 60335.2.40 Particular requirements for electrical heat pumps, air conditioners and dehumidifiers (IEC 60335-2-40 Ed 7)

AS/NZS 60335.2.75 Particular requirements for commercial dispensing appliances and vending machines

AS/NZS 60335.2.89 Particular requirements for commercial refrigerating appliances with an incorporated or remote refrigerant condensing unit or compressor

NZS 5433 Transport of dangerous goods on land

ISO 10156 Gas cylinders — Gases and gas mixtures — Determination of fire potential and oxidizing ability for the selection of cylinder valve outlets

ISO 11650 Performance of refrigerant recovery and/or recycling equipment

AIRAH Flammable Refrigerants Safety Guide (including update 1 2018)

AIRAH DA19 HVAC&R Maintenance

ANSI/AHRI 580 Non-Condensable Gas Purge Equipment for Use with Low Pressure Centrifugal Liquid Chillers

AHRI 700 Specification for Refrigerants

AHRI 740 Performance Rating of Refrigerant Recovery Equipment and Recovery/ Recycling Equipment

ARC Handle Class A2/A2L Flammable Refrigerants

NIST REFPROP Reference Fluid Thermodynamic and Transport Properties Database (REFPROP): Version 10

Refrigerants Australia Flammables fact sheets (WA)

CCCANZ Flammable refrigerants – be informed, be aware (NZ)