“If businesses are going to invest money in equipment that’s supposed to last for decades, can we help them just leapfrog over temporary solutions to something that’s future proof?” asked Suzanne Hagell, Chief of the GHG Mitigation Bureau, Office of Climate Change, New York State Department of Environmental Conservation (NYSDEC). “That’s what we would rather spend public funds on.”
Hagell was referring to natural refrigerant-based refrigeration. “We’re not saying you can’t use HFOs, it’s just not what we would invest in,” she added. “We support natural refrigerants.”
Hagell shared these comments during a presentation in the policy and standards session at the ATMOsphere (ATMO) America 2026 conference, where she explained why New York enacted its HFC regulations and how they would lead to replacing HFCs with natural refrigerants. Organized by ATMOsphere (publisher of NaturalRefrigerants.com), ATMO America 2026 took place June 2–3 in Tarrytown, New York.
In December 2024, NYDEC announced that it had finalized updated regulations to reduce emissions of HFCs, adding 20-year GWP limits of 10 for many new HVAC&R systems starting in 2034. The regulations amended 6 NYCRR Part 494, Hydrofluorocarbon Standards and Reporting, establishing GWP thresholds for refrigerants and requirements for equipment leakage. They did not require the replacement of existing equipment prior to the end of its useful life
The original Part 494 regulations were adopted in 2020 to backstop SNAP (Significant New Alternative Policy) Rules 20 and 21, set by the U.S. Environmental Protection Agency (EPA), and to align with states belonging to the US Climate Alliance, a group of 23 states, including New York, plus Guam.
New York’s amended HFC regulations are among the most ambitious in the U.S., surpassing in some respects the American Innovation and Manufacturing (AIM) Act, implemented by the EPA. Other states with proactive HFC regulations include California and Washington.
Net zero emissions by 2050
The new HFC rules were designed to help implement New York’s Climate Leadership and Community Protection Act (CLCPA), which required the state to reduce greenhouse gas emissions from 1990 levels by 40% by 2030 and by 85% by 2050, achieving net zero emissions.
New York’s final 2026 budget, passed the week of May 27, eliminated the 2030 requirement and replaced it with a 60% reduction target by 2040, qualified by the phrase “to the maximum extent feasible and cost effective.” The 2050 mandate of 85% reduction remains unchanged. The state also changed its emissions counting method from a 20-year GWP basis to a 100-year GWP basis. Hagell said she did not regard these changes as materially impacting the Part 494 HFC regulations or “what we need to achieve with HFCs.” In regard to the 20-year-GWP, “the exact text that refers to GWP20 values is still in place,” she said. “If an entity wanted to sell or install equipment with a GWP20 above the stated values after the prohibition deadline, they would have to seek relief from the agency such as through a variance application.”
State HFC regulations like those enacted by New York, California and Washington have been criticized for creating a fragmented regulatory framework in the U.S. But Hagell defended the New York Part 494 regulations as being a necessary safeguard and enabler of the state’s net zero goal, given the uncertain political climate at the federal level and the checkered history of the EPA’s HFC regulations.
In 2017, the U.S. Court of Appeals for the D.C. Circuit struck down a 2015 EPA rule that phased out HFCs under the Clean Air Act. In May of this year, the EPA finalized a reconsideration of the Technology Transitions Rule (part of the U.S. AIM Act, enacted in 2020 to address the Appellate Court’s objections), postponing the imposition of stricter limits on HFCs from 2027 to 2032.
“We’d rather have a [state] regulation that doesn’t change, and this is the law, and this is what we’re going to see implemented [rather] than keep having to play this game,” said Hagell.
The amended Part 494 regulations have faced pushback in New York. In April, an effort began in the New York State Legislature to roll back the regulations so that they match U.S. AIM Act.
Separately, in January the AHRI and HARDI trade groups appealed a court decision in December rejecting their action to void the updated Part 494 HFC regulations in New York in their entirety. In May HARDI was granted a preliminary injunction that would halt a ban on bulk virgin sales of R404A and R507A under Part 494 until the outcome of the appeal is decided.
Reining in HFCs
Hagell stressed the importance of 2050 state and corporate net zero CO2e emission goals as well as national determined contributions (NDCs) from countries to keep global temperatures from rising beyond tolerable levels. According to the 2025 UNEP Emissions Gap Report, these actions offer a 21% chance of staying below a 1.5°C (2.7°F) increase in warming (vs. zero percent under business-as-usual) and a 78% chance of staying under 2°C/3.6°F (vs. 8%). “We don’t have infrastructure that’s ready for 1.5°C, let alone as you get higher,” she said.
Though a small percentage of total CO2e emissions, HFCs have an outsized impact due to their GWP, which is hundreds to thousands of times that of CO2 (whose GWP is one.) And since being broadly introduced in the marketplace in 1990 to replace ozone-depleting refrigerants, HFC emissions have grown dramatically, Hagell noted.
While overall greenhouse gas emissions in the U.S. declined by 4% between 1990 and 2023, HFC emissions shot up 300%. According to the 2025 UNEP report, in 2024 HFC emissions increased globally by 3.8% while fossil fuel emissions were down 1.1%. HFCs were only 4% of overall U.S. emissions in 2023, but that level, left unchanged, would constitute 20% of overall emissions in 2050. “It’s not the trajectory we want for HFCs,” she said.
Hagell referred to New York’s Climate Action Council Scoping Plan, which supported Part 494 amendments with recommended actions enabling the transition of equipment to low-GWP refrigerants and the reduction of HFC emissions. Part of the Scoping Plan was electrification that would include the installation of heat pumps.
In her presentation, Hagell showed a chart indicating how CO2e emissions would look in 2050 following electrification without an HFC phasedown (33MMT), with the implementation of the EPA’s 2023 Technology Transitions rule, since amended (10MMT) and with the rollout of the amended Part 494 regulations (2MMT). “We still needed more to achieve our 2050 requirement in New York, and that’s where Part 494, based on our projections, could help get us,” she said.
“We’d rather have a [state] regulation that doesn’t change, and this is the law, and this is what we’re going to see implemented [rather] than keep having to play this game.”
Suzanne Hagell, New York State Department of Environmental Conservation
Hagell noted that the Part 494 regulations adopted several EPA regulations of HFCs, including the EPA SNAP program and the Technology Transition regulation. “We also added refrigerant management to line up with EPA programs and our sister states, and we added the EPA’s Greenhouse Gas Reporting Program,” she said.
The NYSDEC continues to enroll end users and manufacturers under Part 494 and “help people understand the program,” Hagell said. “We’ve got lots of opportunities for educating consumers. We’re starting with our state agencies, our state campuses and food banks.”
NYSDEC and the North American Sustainable Refrigeration Council (NASRC) run a funding program with a $500,000 (€438,650) budget to support the installation of natural refrigeration systems in disadvantaged communities or by end users that serve a disadvantaged community.
While Hagell is focused on greenhouse gas emissions, the NYSDEC and other state agencies like the Department of Health are tracking the PFAS issue as it relates to HFO refrigerants, she said. Commonly used HFO-1234yf, while having a negligible GWP, breaks down completely in the atmosphere into trifluoroacetic acid (TFA), an ultrashort-chain PFAS that is widespread in the environment.
This article was updated on August 3 with a comment from Suzanne Hagell regarding New York’s 20-year GWP as it applies to the Part 494 regulations.
