On Oct. 24, 2017, the California Air Resources Board (CARB) held a public workshop to announce two proposed regulations affecting refrigeration and air conditioning equipment manufacturers, end users, contractors, and service technicians.

The first proposed regulation simply preserves existing U.S. Environmental Protection Agency (EPA) requirements prohibiting certain high-global warming potential (GWP) refrigerants in new and retrofitted equipment. The existing regulations are Rules 20 and 21 of the Significant New Alternatives Policy (SNAP) program that regulate ozone-depleting substances and their substitutes, most notably, hydrofluorocarbons (HFCs).

The second proposed regulation focuses on the prohibition of high-GWP refrigerants in new refrigeration and air conditioning equipment, beginning in 2021; the sales restriction of refrigerants with a GWP of 2,500 or greater, beginning in 2020; and a sales restriction of refrigerants with a GWP of 1,500 or greater, beginning in 2024.


Before goin into the details, more background information may be in order.

By law (California Senate Bill 32 of 2016), California must reduce all greenhouse gas (GHG) emissions in the state to 40 percent below 1990 levels by the year 2030. The ambitious reduction target is intended to reduce the harmful effects of GHG emissions that contribute to global warming.

Most GHG emissions in the state are from carbon dioxide emitted from gasoline and diesel vehicles, electricity production, and natural gas used for heating. About 10 percent of all GHG emissions are from fluorinated chemicals that are largely refrigerants with some contribution from aerosol propellants and insulating foam expansion agents.

With the phaseout of chlorofluorocarbons (CFCs) and the upcoming hydrochlorofluorocarbon (HCFC) phaseout date only two years away, HFC usage continues to increase. HFCs now account for about 4 percent of all GHG emissions in California, but that number will double without additional measures.

A subgroup of greenhouse gases, known as “super pollutants” or short-lived climate pollutants (SLCPs), present a significant contribution to global warming because they are hundreds to thousands of times more warming than carbon dioxide. The SLCPs consist of HFCs, methane, and black carbon (soot). California Senate Bill 1383 of 2016 requires a 40 percent reduction of HFCs and methane emissions below 2013 levels by 2030 and a 50 percent reduction in black carbon.

To meet the requirements of Senate Bill 1383, CARB needed to develop HFC emissions reductions measures, which brings us back to the two proposed regulations.

The August 2017 decision in the court case of Mexichem Fluor vs. the U.S. EPA vacated SNAP Rule 20. However, it remains in effect while the decision is being appealed. SNAP Rule 20 prohibits R-404A, R-507, and other high-GWP refrigerants in new supermarket refrigeration equipment, remote condensing units, stand-alone (self-contained) equipment, and refrigerated vending machines.

Supermarket refrigeration requirements for new equipment began Jan. 1, 2017, and the remote condensing unit requirements began Jan. 1, 2018. Self-contained equipment and vending machine requirements follow in 2019. SNAP Rule 21, which would become unenforceable if Rule 20 is vacated, prohibits R-404A and R-507 in new cold storage facilities beginning in 2023, and HFC-134a and R-410A in new chillers beginning in 2024.

To meet the California HFC reductions goal, CARB counted on reductions coming from SNAP rules, which are in jeopardy of being permanently vacated. To preserve the status quo (at least in California), CARB proposes to adopt the requirements of SNAP Rules 20 and 21 to maintain continuity and provide some certainty to equipment manufacturers that they should continue to plan for the transition to lower-GWP refrigerants. The proposal is planned to go to the Air Board for approval in March.

In all likelihood, end users, contractors, and service technicians will scarcely notice any changes to new refrigeration equipment as a result of the SNAP rules. For example, a new refrigeration unit could be built to use R-407A instead of R-404A. Both are common nonflammable refrigerants that have been used by technicians for years, and the new equipment will be very similar to current equipment.

Unlike the adoption of SNAP requirements, the second proposed regulation will require changes for equipment manufacturers, end users, contractors, and service technicians. The proposed regulation is expected to go before the Air Board for approval in December. The requirements as announced in October 2017 are listed below.

  • Beginning Jan. 1, 2021, refrigerants with a GWP of 150 or greater are prohibited in new stationary refrigeration equipment with a charge size of 50 pounds or greater;
  • Beginning Jan. 1, 2021, refrigerants with a GWP of 750 or greater are prohibited in new stationary air conditioning equipment with a charge size of 2 pounds or greater; and
  • Sales restriction on refrigerants with a GWP of 2,500 or greater to begin Jan. 1, 2020, followed by a sales restriction on refrigerants with a GWP of 1,500 to begin Jan. 1, 2024.


With all the proposed prohibitions, which refrigerants are acceptable and likely to take the place of high-GWP HFCs?

For refrigeration, the only common refrigerants that are non-ozone depleting and have a GWP less than 150 are the “natural” refrigerants carbon dioxide, ammonia, and hydrocarbons; HFC-152a (more commonly used as an aerosol propellant); and the newest class of synthetic refrigerants, the hydrofluoroolefins (HFOs). For air conditioning systems, refrigerants with a GWP less than 750 include HFC-32 (R-32) and many new HFO-HFC blends.

Let’s explore some of the changes that may occur as a result of the regulations.

Equipment manufacturers will be designing, testing, and building systems that may operate under very high pressure (CO2), be toxic (ammonia), slightly flammable (HFOs), or highly flammable (hydrocarbons). Service technicians will have to undergo additional safety and technical training on flammable and high-pressure refrigerants (ammonia refrigeration has been around long enough to have well-established training and operating guidelines). End users must have additional safety precautions in place for the new equipment. Contractors may have to work closely with local permitting agencies that will be uninformed and skeptical of low-GWP refrigerants.

New air conditioning equipment will likely use slightly flammable refrigerants. Although these refrigerants are not currently allowed in most systems because they do not meet applicable codes and standards, we expect updated codes and standards that allow these refrigerants in a year or two. The updated codes and standards may require additional flammability mitigation, such as the addition of refrigerant sensors and rapid venting capability in case of leaks.

Many contractors and service technicians have already seen several major changes in the types of refrigerants allowed, and another change is looming right now.  

Additional information on the proposed refrigerant regulations in California is available on the CARB web page at: https://ww2.arb.ca.gov/our-work/programs/hfc-reduction-measures (follow links to Rulemaking).

Publication date: 1/8/2018