Evaluation of the Fire Hazard of ASHRAE Class A3 Refrigerants in Commercial Refrigeration Applications
Due to potential environmental impact, there has been a shift to consider use of natural refrigerants, which have a lower Global Warming Potential (GWP) than traditional fluorocarbon-based refrigerants. One type of natural refrigerant is hydrocarbons (e.g. propane). They are classified as Class A3 refrigerants per ASHRAE Standard 34. Previous work has been completed on Class A2L refrigerants, but Class A3 refrigerants require more study in order to provide technical basis for any changes to the current limits for use in refrigerator units. There fire hazard of Class A3 refrigerants, and specifically propane in larger volumes, need to be evaluated as alternatives to traditional refrigerants. This study evaluated the flammability hazard of R-290 propane in refrigeration appliances used in commercial retail and kitchen settings. R-290 is slightly different propane than your household BBQ-grill-variety (unodorized), but composition-wise it is the same.
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