12 JUN 2020 USA: The US Environmental Protection Agency (EPA) is proposing to add R32 and five other A2L refrigerants as lower GWP alternatives to R410A in smaller air conditioning units.

The EPA proposes to SNAP-list the lower GWP, “mildly flammable” refrigerant R32, along with R452B, R454A, R454B, R454C and R457A as acceptable, subject to use conditions, for use in new residential and light commercial air conditioning and heat pumps.

The SNAP (Significant New Alternatives Policy) was established to identify and evaluate substitutes for ozone-depleting substances. The list approves and prohibits chemicals used in a variety of consumer and industrial applications.

The EPA proposes that these refrigerants may only be used in new self-contained and split-system air conditioning equipment specifically designed for use with the refrigerants. Limits are placed on charge sizes, and include greater ventilation requirements, refrigerant leak sensors, alarms and self-shutoff valves. In addition the proposal stipulates the inclusion of a number of safety and flammability warning labels both inside and outside the equipment.

R32, a single component refrigerant with a GWP of 675, is already being adopted around the world by most unitary equipment manufacturers as the leading replacement for R410A. Since 2015, it has been SNAP- listed for use in the USA in new self-contained room air conditioning units.

The other five refrigerants are blends made up of varying amounts of R32, R125, R1234yf and R152a. One of the refrigerants, R457A, is manufactured by Arkema and marketed as Forane 457A. The others are all Chemours gases: R452B, also known as Opteon XL 55, R454A (Opteon XL 40) R454B (Opteon XL 41) and R454C (Opteon XL 20).