Today’s commercial refrigerators can contain many different types of refrigerants. Not so long ago all machines used one of the three basic refrigerants: R-12 (Dichlorodifluoromethane), R-22 (Chlorodifluoromethane), and R-502 (a mixture of R-22 and R-115). But in recent years advances in refrigerant technology and pressure to tackle global warming have lead to a wide range of different refrigerants being used across all refrigeration equipment. Foster Refrigerator lead the way in energy efficient, 'green', and environmentally friendly commercial refrigeration equipment. All Foster Refrigerator cabinets now come with a Hydrocarbon option at no extra cost. Hydrocarbon refrigerants (HCs) are widely recognized as environmentally friendly refrigerants because they have an ozone depleting potential (ODP) of zero, and relatively low global warming potential (GWP). Currently, only three HC refrigerants have been approved for use in domestic and commercial refrigerators. Their usage is currently restricted to only new systems and in limited quantities. The approved refrigerants are R-290 (propane), R-600a (isobutene), and R-441A (a blend).