Modeling and Simulation to Gain Flammable Refrigerant Leakage Risk Insights

Hydrocarbon based refrigerants have favorable environmental characteristics, however, they introduce an added fire risk as compared to previous generations of refrigerants (Figure 1). The added fire risk is directly related to the higher flammability of hydrocarbons, especially if there is a leak in a refrigeration system.  The leaked gas could be ignited by nearby hot surfaces or electrical components. To understand and address the risks, international safety standards such as EN 378, IEC 60335-2-40, IEC-60335-2-89, ISO 5149 or regional standards like ASHRAE 15 or UL 60335-2-40 (for the U.S.) prescribe physical test methods. However, there is a challenge and a limit to using physical testing to thoroughly understand the potential risks associated with leakage of a combustible refrigerant in confined spaces.