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Please note: This summary is provided to help you understand the regulations. Consult the references provided for links to the full text of the regulations.

HVACRefrigeration Systems and Heating, Ventilation, Air Conditioning (HVAC)

Road Rail Air Water

This section covers U.S. Environmental Protection Agency (EPA) air pollution regulations affecting air conditioning and refrigeration systems that contain ozone depleting substances (ODSs). These regulations apply to refrigerant fluids found in both vehicle and building cooling systems.


Who is covered by the regulations?

Clean Air Act (CAA) regulations apply to all transportation operations that own or service air conditioning and refrigeration equipment. This includes both stationary sources (HVAC systems and refrigerated storage areas in buildings) and mobile sources (refrigeration units in vehicles).

What is the purpose of the regulations?

The stratospheric ozone layer shields the Earth from the sun's harmful ultraviolet radiation. Emissions of certain synthetic chemicals - including chlorofluorocarbons (CFCs), halons, and hydrochlorofluorocarbons (HCFCs) - that are commonly used as refrigerants, solvents, and insulating foams destroy the ozone layer and have created an "ozone hole" over the South Pole. In addition, many of these ozone-depleting substances (ODS), as well as their substitutes, are greenhouse gases that contribute to climate change.

Due to the global nature of the problem, in 1987 many countries, including the U.S., signed an international treaty, the Montreal Protocol, which is designed to protect the ozone layer by phasing out the production of a variety of substances believed to be responsible for ozone depletion. Since 1987, all United Nations (UN) countries have signed the treaty and it has undergone many revisions. To meet U.S. obligations, EPA has issued stratospheric ozone protection regulations under Title VI of the Clean Air Act.

Regulations

Various sections of CAA Title VI impact the transportation industry in terms of operating and servicing existing air conditioning or refrigeration equipment. Businesses should also be aware of these rules when purchasing new equipment. Key issues are discussed below.

CFC and HCFC Phaseout. The U.S. Environmental Protection Agency (EPA) regulates the production and importing of gases used in air conditioning and refrigeration units. From the early 1990's to present, there has been and continues to be a transition of gases used in air conditioning and refrigeration.  The driving force was originally the Montreal Protocol (ratified by the United States in 1988), a global agreement to protect the Earth's ozone layer by phasing out the chemicals that deplete it.  The Clean Air Act (CAA) in the United States includes Title VI, which is specifically designed to align with the Montreal Protocol's goals and regulations for phasing out ozone depleting substances (ODS).

In the U.S., ODS are regulated as class I or class II controlled substances. Class I substances, such as chlorofluorocarbons (CFCs) and halons, have a higher ozone depletion potential and have been phased out; with a few exceptions, this means no one can produce or import class I substances. Common examples of CFCs include R-11, R-12, R-13, R-113, R-114, and R-115. Class II substances are all hydrochlorofluorocarbons (HCFCs), which were transitional substitutes for many class I substances. New production and import of most HCFCs were phased out as of 2020 and they were mostly replaced with hydrofluorocarbons (HFCs). Commonly used hydrofluorocarbons (HFCs) include R-134a, R-410A, R-32, and R-125. These are synthetic gases primarily used as refrigerants in air conditioning and refrigeration systems, as well as in other applications like fire suppression and foam blowing.

HFC Phaseout. Although HFCs served as a temporary solution to ozone layer depletion, they have a high global warming potential (GWP), a measure of how much heat a greenhouse gas traps in the atmosphere compared to carbon dioxide (CO2) and contributes to climate change. The climate impact of HFCs can be hundreds to thousands of times greater than carbon dioxide.

The parties to the Montreal Protocol meet once a year to make decisions aimed at ensuring the successful implementation of the agreement. These include adjusting or amending the Protocol. An amendment (Kigali Amendment), called for the phase-down of hydrofluorocarbons (HFCs) in 2016. The Kigali Amendment aims to reduce global HFC production and consumption by more than 80% over the next 30 years. In the United States, the American Innovation and Manufacturing (AIM) Act of 2020, mirrors the Kigali Amendment's goals by authorizing the Environmental Protection Agency to phase down HFCs in a stepwise manner by 2026 This legislation allows the U.S. to fulfill its obligations under the international agreement and potentially benefit from the global transition to more sustainable technologies.

Please note that the phasedown and restrictions on the use of certain hydrofluorocarbons is being reconsidered by the Trump Administration. For more information, see: Powering the Great American Comeback Fact Sheet.

HFC Alternatives. EPA's Significant New Alternatives Policy (SNAP) program identifies and approves acceptable substitutes for HFCs in various applications, including refrigeration, air conditioning, and aerosols. 

Alternatives to HFCs (hydrofluorocarbons) include natural refrigerants like ammonia, carbon dioxide, and hydrocarbons, as well as synthetic options like hydrofluoroolefins (HFOs). These alternatives aim to reduce the significant global warming impact of HFCs, which are potent greenhouse gases.  Specific examples include:

  • R-1234yf is a refrigerant used in many modern vehicle air conditioning systems. It's a newer, more environmentally friendly alternative to the older R-134a refrigerant. R-1234yf has a significantly lower global warming potential (GWP) than R-134a. 
  • R744 (carbon dioxide) is a natural refrigerant gaining traction in refrigeration and air conditioning systems due to its low environmental impact, despite its high operating pressures. It has a Global Warming Potential (GWP) of 1, meaning it doesn't contribute to ozone depletion and has a minimal impact on climate change compared to other refrigerants. 

For more information, see SNAP Substitutes by Sector.

Servicing Existing Equipment (Title VI Sections 608 and 609). The purpose of sections 608 and 609 of the Clean Air Act (CAA) are to minimize the quantity of refrigerants released to the atmosphere, and to maximize the recovery and recycling of refrigerants during the servicing and disposal of mobile and stationary air conditioning and refrigeration equipment. Requirements include:

  • Technician certification
  • Mandatory use of recovery and recycling equipment
  • Service practices that minimize refrigerant emissions
  • Prohibition of venting,
  • Equipment certification
  • Leak repair
  • Proper disposal,
  • Recordkeeping

Section 608 of the Clean Air Act directs the EPA to establish requirements to prevent the release of ozone-depleting and certain other refrigerants during the servicing, repair or disposal of appliances and industrial process refrigeration systems. This includes the scrapping/salvage of vehicles that have a mobile A/C system. Section 608 covers procedures involving motor vehicle air conditioners (MVACs) that are not covered by Section 609, such as the disposal of MVACs. Below is information concerning specific areas where the overlap between these two sets of regulations may require clarification.

Section 609 of the Clean Air Act establishes standards specifically for the service of MVACs. MVACs are included in the definition of appliances under the stipulations put forth in Section 608; however, since their service and repair are regulated under Section 609, they are not subject to the servicing requirements put forth in Section 608.

Note that the transportation industry is somewhat fragmented under the 608/609 rules. Truck cabs fall under the MVAC category and are therefore regulated under section 609. Trains, aircraft, ships/boats (passenger and cargo), and refrigerated tractor trailers are not considered MVACs and therefore not regulated under section 609. However, the section 608 regulations apply to these modes of transportation.

Technician Certification (Title VI Sections 608 and 609). Both regulations require that technicians become certified. Which certification you need depends on what equipment you are servicing. Technicians who repair or service MVACs must be trained and certified by an EPA-approved Section 609 program. These programs are specifically designed to cover MVAC refrigerant recovery, recycling and charging equipment and procedures in accordance with SAE Standards and Section 609 regulatory requirements. After completing a required training program, MVAC technicians must pass a test to become certified.

Under Section 608, the EPA has established four types of certification for technicians that service and repair appliances other than MVACs. To be certified, technicians must pass a test for the appropriate appliances. All training and review classes for Section 608 are voluntary; only passing the test is mandatory. The four categories of certification are:

  • Type I: Small appliances
  • Type II: High-pressure appliances, except small appliances & MVACs
  • Type III: Low-pressure appliances
  • Type IV (Universal): All appliances except MVACs

Within the transportation industry, technician certification can get tricky. For example, in a dairy truck, the hermetically sealed refrigeration unit used to keep the dairy products cold is regulated under section 608 while the CFC-12 comfort cooling system for the driver is regulated under section 609.

For more on certifications, see Section 608 Certification and Section 609 Certification respectively.

Leak Repair (Title VI Section 608). The leak repair requirements, promulgated under Section 608 of the Clean Air Act, require that when an owner or operator of an appliance that normally contains a refrigerant charge of more than 50 pounds discovers that refrigerant is leaking at a rate that would exceed the applicable "trigger rate" during a 12-month period, the owner or operator must take corrective action.

In general, owners or operators must either repair leaks within thirty days from the date the leak was discovered, or develop a dated retrofit/retirement plan within thirty days and complete actions under that plan within one year from the plan's date. More information, see Section 608 Leak Repair.

For all appliances that have a refrigerant charge of more than 50 pounds, the following trigger leak rates for a 12-month period are applicable:

Appliance Type
Trigger Leak Rate
Commercial refrigeration
20%
Industrial process refrigeration
30%
Comfort cooling
10%
All other appliances
10%

Leak Repair Proposed Amendments (Title VI Section 608). EPA has proposed changes to the leak repair regulations promulgated under Section 608 of the Clean Air Act. Specifically, EPA is proposing to lower the leak repair trigger rates for comfort cooling, commercial refrigeration, and industrial process refrigeration and air conditioning equipment (i.e., appliances) with ozone-depleting refrigerant charges greater than 50 pounds. This action proposes to streamline existing required practices and associated reporting and recordkeeping requirements by establishing similar leak repair requirements for owners or operators of comfort cooling, commercial refrigeration, and industrial process refrigeration appliances. This action also proposes to reduce the use and emissions of Class I and Class II controlled substances (such as but not limited, to CFC-11, CFC-12, HCFC-123, HCFC-22) by requiring the following:

  • Verification and documentation of all repairs,
  • Retrofit or retirement of appliances that cannot be sufficiently repaired
  • Mandatory replacement of appliance components that have a history of failures
  • Mandatory recordkeeping of the determination of the full charge and the fate of recovered refrigerant

Refrigerant Recycling Rule (Title VI Section 608). Under Section 608 of the CAA, EPA has established regulations (40 CFR Part 82, Subpart F) that:

  • Require service practices that maximize recovery and recycling of ozone-depleting substances (both chlorofluorocarbons [CFCs] and hydrochlorofluorocarbons [HCFCs] and their blends) during the servicing and disposal of air-conditioning and refrigeration equipment.
  • Set certification requirements for refrigerant recycling and recovery equipment, technicians, and refrigerant reclaimers.
  • Restrict the sale of refrigerant to certified technicians.
  • Require persons servicing or disposing of air-conditioning and refrigeration equipment to certify to EPA that they have acquired refrigerant recovery and/or recycling equipment and are complying with the requirements of the rule.
  • Require the repair of substantial leaks in air-conditioning and refrigeration equipment with a refrigerant charge greater than 50 pounds.
  • Establish safe disposal requirements to ensure removal of refrigerants from goods that enter the waste stream with the charge intact (e.g., motor vehicle air conditioners, home refrigerators, and room air conditioners).
  • Owners/operators of appliances normally containing 50 or more pounds of refrigerant must keep servicing records documenting the date and type of service, as well as the quantity of refrigerant added, for at least three years.

For more information, see: Complying With The Section 608 Refrigerant Recycling Rule.

Compliance Options

Compliance with all aspects of the Title VI regulations is mandatory and EPA is authorized to assess fines of up to $37,500 per day for any violation of these regulations. Basically, compliance can be achieved through one of two ways:

  • Diligent monitoring and servicing of existing equipment containing ODCs.
  • Replacing existing ODC equipment with new equipment containing substitutes.

EPA rules do not expressively prohibit use of older equipment (although most modifications are prohibited). However, servicing older units and replacing their ODCs is becoming more and more expensive mainly due to the decreased availability and increased prices of these chemicals. This is especially true if you are faced with a major repair. As an alternative strategy, many businesses maintain compliance, save money and reduce their liability and environmental impact by purchasing new, more efficient and compliant equipment.

Best Practices

The following resources are related to best practices and include ideas on building design and equipment improvements:

More Resources

Frequent Questions on the Phasedown of Hydrofluorocarbons. This page features responses to common questions on the phasedown of hydrofluorocarbons (HFCs) under the American Innovation and Manufacturing (AIM) Act.

Protecting Our Climate by Reducing Use of HFCs. Links to proposed rules, technology transitions, grants, and additional information.

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