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Refrigerant Classifications Groups
What is the classification of R-502 refrigerant?
R-502 is in the A-1 Group Classification. See the refrigerant safety group classification matrix in ASHRAE 15-1994 section 6.1. The classification in part reflects the amount of refrigerant that is allowed in occupied space or the type of mechanical room equipment installed. For example, if flammable refrigerants might leak from a system the room must meet special electrical and ventilation requirements. SPS 345 refers to Group A1, B1, A2, B3, A3, and B3 refrigerant.
How do I determine what group the refrigerant I use falls in?
See SPS 345.32. This section refers readers to IMC 1102.2 and Table 1103.1. Table 1103.1 lists numerically by R# all refrigerants classified as per ASHRAE 34 with applicable A1, B1, A2, B2, A3 and B3 classifications.