- “refrigeration installation”: the whole of the parts and appliances necessary for the operation of a refrigeration system; this also concerns air-conditioning installations and heat pumps that contain a refrigeration system;

- “refrigerant”: fluid that is used in a refrigeration installation for the transfer of heat, which absorbs heat at a low temperature and pressure and which removes heat at a higher temperature and pressure, whereby the physical state of the fluid usually changes;

- “refrigeration system”: whole of parts that contain refrigerant and that are connected to each other in contained conditions in which the refrigerant circulates with the intention of the abstraction or removal of heat;

- "nominal refrigerant content": the quantity of refrigerant with which a refrigeration system is filled to function in the conditions for which it is designed, and whereby the quantity of refrigerant in a buffer or reserve tank connected to the refrigeration installation is also calculated; this is normally the quantity introduced with the first bringing into use;


- “relative rate of leakage”: the fraction of the nominal refrigerant content that as a result of emissions is lost from the entire installation during a calendar year, proportionate to the nominal refrigerant content. The relative rate of leakage is calculated using the volumes of refrigerant that are added to a system. The relative rate of leakage is determined using the following formula:

L = (B/N) x 100%, where:

1° L: relative rate of leakage;

2° B: sum of all refills during a calendar year (kg);

3° N: nominal refrigerant content of the refrigeration installation (kg).

- "competent refrigeration technician": a technician who is appointed to carry out activities in refrigeration installations in a responsible manner, either directly by the operator, or by the refrigeration company that carries out activities in the refrigeration installation. When carrying out work on refrigeration installations with fluorinated greenhouse gases or ozone layer-depleting substances as stated in Article, §9, Article, §1bis, Article 5bis., §1, Article 5bis., §1 and Article, the competent refrigeration technician shall possess accreditation as a refrigeration technician as stated in Article 6, 2°, e) of the VLAREL for the category in question, namely I, II, III or IV;



- “air-conditioning system”: any combination of the components required to provide a form of indoor air treatment in which temperature is controlled or can be lowered. A reversible heat pump is regarded as an air-conditioning system;


- "nominal refrigeration capacity": the total installed refrigeration capacity specified by the manufacturer and calculated according to standard conditions, as specified in EN 14511-2. If the air-conditioning system at building level consists of a number of individual installations, the capacities of the various individual installations are added together;

- “building”: a roofed construction having walls, for which energy is used to condition the indoor climate.

- "tonne CO2 equivalent": a quantity of greenhouse gases, expressed as the product of the weight of the greenhouse gases in metric tonnes and their global warming potential;

- "global warming potential": the climatic warming potential of a greenhouse gas in relation to that of CO2, calculated in terms of the warming potential over a period of one hundred years of one kilogram of a greenhouse gas in relation to one kilogram of CO2, as stated in Appendix I, II and IV to Regulation (EU) No 517/2014 of the European Parliament and of the Council of 16 April 2014 on fluorinated greenhouse gases and repealing Regulation (EC) No 842/2006 or, for mixtures, calculated according to the method stated in Appendix IV to the same Regulation.