Drawing of a nonspecific chemical molecule

Federal & International Landscapes

International Landscape:

The 1987 Montreal Protocol on Substances that Deplete the Ozone Layer is a global agreement aimed at protecting the Earth’s ozone layer by phasing out the production and use of ozone depleting substances (ODS).  Four amendments to the Montreal Protocol exist, with the most recent being the Kigali Amendment which added HFCs to the list of substances to the phased down.

The U.S. signed the Kigali Amendment in 2016 but has not ratified it. In January 2021, President Biden signed Executive Order 14008: Tackling the Climate Crisis at Home and Abroad, directing the administration to forward the Kigali Amendment for Senate ratification.

Federal Landscape:

To align with the goals under the Montreal Protocol, Congress amended the Clean Air Act in 1990 to regulate ODSs. In accordance with CAA Section 612(c) which directs the Environmental Protection Agency to consider if the substitute “reduces the overall risk to human health and the environment” and is “currently or potentially available,” the EPA established the Significant New Alternatives Policy (SNAP) program which would approve “safer” substitutes for ODSs--a full listing of SNAP rulemakings can be found here.

HFCs were intended to replace ODS, being referred to as “substitute refrigerants” under the CAA, and throughout the 1990s and early 2000s EPA approved several HFCs and HFC-blends as acceptable uses for ODS under SNAP for products ranging from aerosols, motor vehicle air conditioners, commercial refrigeration and foams. However, as science evolved, the EPA began to promulgate additional regulatory changes and requirements for HFCs in 2015 to address HFC emissions and their “atmospheric effects.”

In 2015 the EPA finalized a rulemaking, commonly known as SNAP Rule 20, which not only altered the listing status for certain HFCs under SNAP, prohibiting manufacturers in the aerosols, refrigeration and air conditioning, and foam blowing sectors, from using HFCs, but also approved several HFC alternatives as acceptable subsites to ODSs.  Part of that rulemaking was later vacated by the U.S. Court of Appeals for the D.C. Circuit in 2017, with the court finding that while the EPA could indeed prohibit a manufacturer from substituting HFCs for ODSs currently used in their products, the agency lacked the authority to require manufacturers that previously replaced ODSs with HFCs to substitute those HFCs with a more climate friendly alternative. In addition, in 2016 EPA finalized a rulemaking, commonly known as SNAP Rule 21 which contains HFC prohibitions that apply to stationary air-conditioning and refrigeration. 

However, response to the court’s 2017 decision, EPA published a rulemaking providing guidance and suspending the prior listing of HFCs as unsafe substitutes in its entirety, and in April 2020 the same court vacated and remanded it back to the agency for further consideration, citing failure to abide by the Administrative Procedure Act and stating that the 2017 decision “did not vacate the HFC listings in the 2015 Rule in their entirety.”

In December 2020 Congress passed the American Innovation and Manufacturing (AIM) Act of 2020 via the Consolidated Appropriations Act of 2021 which directed the EPA to address HFCs by providing the agency with new authorities in three main areas: to phase down the production and consumption of listed HFCs, manage these HFCs and their substitutes, and facilitate the transition to next-generation technologies. AIM directs the EPA to phase down HFC production and use by approximately 85% over the next 15 years but provides a five-year exception from HFC regulation for niche applications deemed “essential uses” including: defense sprays, medical inhalers, semiconductor manufacturing, certain insulating foams, and mission critical military end uses. Of most importance for states—the AIM Act includes a five-year state preemption provision which prohibits states from enforcing their own HFC laws or actions restricting the management or use of the exempted HFCs for five years.

In October 2021 the EPA issued its final rule establishing an allowance-based trading program to implement the phasedown required by the AIM Act. The rulemaking directs the phasedown of listed HFCs to 15% of their baseline levels in a stepdown manner by 2036. For more information visit EPA’s fact sheet here.

State Legislative Landscape:

Since the promulgation of both EPA SNAP Rules 20 and 21, 12 states have taken action to reduce the use of HFCs, either through legislation or administrative regulation, and as of September 2021 four more states are in the process of developing rules restricting the use of HFCs.  Most of these new rules are heavily based on the EPA SNAP rules, with some incorporating them by reference. These laws focus on the production and sale of new, large-scale products and systems that use HFCs, and most do not affect existing products and systems manufactured before the rule’s effective date. Many include a phaseout schedule, where use of HFCs will be prohibited by a particular date. The phaseout schedule allows time for manufacturers to transition.


Cal. HSC § 39730.5 (2016) directs the state Air Resources Board to adopt and implement regulations to achieve a 40% reduction in hydrofluorocarbon gases by 2030.

These regulations, adopted in 2018, prohibit the use of HFCs in many applications as well as products manufactured after the specified deadlines.

Senate Bill 1013 (enacted, 2018) codifies the schedule for phasing out HFCs consistent with SNAP Rules 20 and 21. The law also established the Fluorinated Gases Emission Reduction Incentive Program to encourage adoption of HFC alternatives.

Colorado (regulatory)

On May 22, 2020, the Colorado Air Quality Control Commission adopted regulations which follow the EPA SNAP prohibitions on certain HFCs in air conditioning and refrigeration equipment, aerosol propellants, and foam end-uses.


Following Governor Carney’s 2019 directive to the state Department of Natural Resources and Environmental Control (DNREC) to develop regulations that would phase out the use of HFCs in the state, the legislature passed House Resolution 60 supporting the Governor’s action and supporting new regulations on the use and manufacturing of HFCs.

In March 2021, the DNREC Division of Air Quality published a final regulation titled Prohibitions on Use of Certain Hydrofluorocarbons in Specific End-Uses in the Delaware Register of Regulations. This regulation prohibits the manufacture and sale of new products which use certain HFCs. It does not affect systems currently in use.


Senate Bill 2760 (2020) (failed)) would have adopted preexisting SNAP requirements into Hawaii state law, phasing out certain products and equipment with HFCs. The bill would have established a state procurement preference for products and equipment that to do not contain HFCs and directs state agencies to evaluate increased use of refrigerants with a low global warming potential (low-GWP).


In June 2021, the Maine legislature enacted LD 226, legislation that establishes a phaseout timeline of most HFCs used in most products. This aligns Maine with the EPA SNAP policies.

Maryland (regulatory)

In November 2020, the Maryland Department of the Environment finalized regulations which establishes a phaseout schedule for the use of HFCs in new products. These new regulations will be available in COMAR chapter 26.11.33.

Massachusetts (regulatory)

Massachusetts adopted 310 CMR 7.76, “Prohibitions on Use of Certain Hydrofluorocarbons in Refrigeration, Chillers, Aerosol Propellants, and Foam End-Uses” which follows the EPA SNAP prohibitions on uses of HFCs in new products.

New Jersey

Assembly Bill 5583 (enacted, 2020) prohibits the sale or use of certain HFC-containing products in the state by codifying the phaseout schedule for HFCs consistent with EPA’s 20 & 21 SNAP rules. The new law also requires the state Department of Environmental Protection to submit a report providing recommendations on how to increase the use of substitutes for HFCs in the state.

Assembly Bill 1193 (pending) would establish an HFC emissions reduction target of 40% below 2018 levels by 2035 and directs the state Department of Environmental Protection to establish an HFC emissions monitoring and reporting program.

New York (regulatory)

The New York Department of Environmental Conservation has adopted 6 NYCRR Part 494, Hydrofluorocarbon Standards and Reporting, which follows the EPA SNAP prohibitions on certain HFCs in new food refrigeration equipment, large air-conditioning equipment, foam, and vending machines. The rule also includes administrative and record-keeping requirements for manufacturers of the affected products.


House Bill 3027 (failed) would have codified the SNAP Rules 20 & 21 for phasing out certain products and equipment containing HFCs. The bill also would have established a state procurement preference for products that are not manufactured with HFCs and do not use HFCs.

Senate Bill 1530 (first committee) directs the state Environmental Quality Commission to adopt requirements consistent with the SNAP Rules 20 & 21 for HFCs and empowers the commission to adopt additional regulations for products that contain HFCs if the commission “determines the equipment or products pose a risk to human health or the environment and that a substitute is currently or potentially available.”

House Bill 3227, signed into law in June of 2021, prohibits the Oregon Department of Consumer and Business Services from outlawing in state building codes certain uses of specific refrigerants authorized under federal law. The purpose of this is to ensure that alternative refrigerants to HFCs which have been deemed safe by the EPA, primarily those listed under the SNAP program, are available to Oregon businesses without conflicting with local law.

Rhode Island

The Department of Environmental Management has proposed a rule that would prohibit the use of HFCs in many kinds of new equipment, in line with the EPA SNAP policies.


Senate Bill 30 (enacted, 2019) prohibits the use of certain products containing HFCs in the state, codifying the phase out schedule in EPA’s 20 & 21SNAP Rules. The new law also directs the Secretary of Natural Resources to propose a rule to phase down hydrofluorocarbons in order to achieve a 40% reduction from 2013 HFC levels by 2030.  (10 V.S.A. § 586)

That regulation, titled “Rules regarding phasedown of the use of Hydrofluorocarbons” was ultimately adopted by the Vermont Department of Environmental Conservation and became effective in December of 2020. It creates deadlines by which no new products or systems may be built with certain HFCs.

Virginia (regulatory)

Following legislation (HB 30, 2020) which required the agency to develop regulation limiting HFC use, the Virginia Department of Environmental Quality finalized regulations that require the production and use of HFCs in the Commonwealth of Virginia, in most applications, to be discontinued by Jan. 1, 2022. These uses follow the EPA SNAP rules.


House Bill 1112 (enacted, 2019) amended various chapters of the Washington code to prohibit the use of certain equipment containing HFCs and codifies EPA’s 20 & 21 SNAP Rules schedules for phasing out the use of HFCs in certain applications. The statute also establishes a state procurement preference for non-HFC products and requires state agencies to complete a report evaluating methods for increasing HFC alternative refrigerants with a low-GWP. (Similar legislation is pending: Senate Bill 5426 (first chamber)). 

House Bill 1050 (enacted, 2021) sets a maximum allowed GWP for HFCs used in stationary refrigeration and air conditioning systems. The bill also expands Washington’s Clean Air Act requirements for ozone-depleting substances to include HFCs and requires the State Building Code Council to develop new standards allowing substitutes with lower global warming potential than HFCs.

Other Work

Connecticut, Pennsylvania and New Mexico have announced their intention to pass new rules on the use of HFCs.

Pennsylvania Regulations which would phase out HFCs are currently in a pre-proposal stage within the Pennsylvania Department of Environmental Protection, as reported by their July 2021 Agenda.

New Mexico Governor Michelle Lujan Grisham issued an executive order in 2019 creating a New Mexico Climate Change Task Force to develop a plan to reduce the state’s greenhouse gas emissions, along with other topics. HFCs are cited in the order as one contributor to climate change. This task force’s 2020 report recommends new rules on the use of HFCs.

Texas has not passed rules that would restrict the use of HFCs, but the legislature passed SB 1210, which would ensure that using alternatives to HFCs approved by the EPA in new buildings is permissible. Specifically, it prohibits any Texas building code or other requirements applicable to commercial or residential buildings, or construction of those buildings, to prohibit the use of alternative chemicals to HFCs when those replacement chemicals have been approved for that use by the EPA.