The Environmental Protection Agency has released its latest proposed rule that would make changes to the Significant New Alternatives Policy program, further restricting uses of what it terms higher global warming potential refrigerants, including HFCs.

forward revisiting the acceptable alternative lists under the SNAP program. They made some revisions last year, and now they’re proposing additional changes in the latest Federal Register notice,” said Lowell Randel, director of government ‎ affairs for IIAR. “That is going to make it that much more attractive to look at utilizing natural refrigerants like ammonia and CO2 .”

IIAR said key staff members last year attended the EPA’s Significant New Alternatives Policy (SNAP) stakeholder meeting on September 11th. The EPA’s SNAP program evaluates and regulates substitutes for the ozone-depleting chemicals that are being phased out under the stratospheric ozone protection provisions of the Clean Air Act (CAA). The intended effect of the SNAP program is to promote a smooth transition to safer alternatives.

IIAR continues to monitor the SNAP program as the EPA identifies alternatives to refrigerants that are currently being considered for draw down due to their ozone-depleting and high global warming potential, the organization said.

Within the new proposed rule, EPA specifically cited ammonia as a viable alternative in a number of places. EPA wrote, “In the original SNAP rule, EPA noted ammonia has been used as a medium- to low-temperature refrigerant in vapor compression cycles for more than 100 years. Ammonia has excellent refrigerant properties, a characteristic pungent odor, no long-term atmospheric risks and low cost.”

The proposed rule applies to refrigerants used in new cold storage warehouses. “By saying they are not going to allow the use of those refrigerants in new facilities, they’re saying, ‘this is where we’re going in the future,’” Randel said.

EPA has not defined a set compliance period, but Randel said he doesn’t expect a long transition time. “If you’re looking at a new facility, you will look to see what your viable options are for the new facility,” he explained.

EPA accepted comments until June 2. “Once they’ve received the public comments, they’ll go through those and publish a final rule,” Randel said, adding that he expects to see a final rule by the end of the year.