A new study conducted by Air Conditioning, Heating and Refrigeration Technology Institute as part of a $5.6million research program joint funded by AHRI, ASHRAE, the California Air Resources Board, and the US Department of Energy used a test scenario to discern the risks associated with using Class A3 refrigerants. The insight developed from these findings will be used to revise IEC/UL 60335-2-40 and IEC/UL 60335-2-89 safety standards.

More information can be found here while the final report can be found here.