1. Executive Summary:
Revisiting Flammable
Refrigerants in HVAC
Equipment and Appliances

2. Executive Summary:
Revisiting Flammable Refrigerants
in HVAC Equipment and Appliances
Since the 1989 Montreal Protocol and its successor agreements, the world of refrigerants has been marked by
change. In the search for more environmentally-preferable refrigerants, technology has moved from chlorofluo-
rocarbons to a host of alternative substances. Many of these substances are serving as interim measures, until the
phase-out of ozone-depleting and global-warming refrigerants meets the targets set by the U.S. Clean Air Act.
In response, HVAC equipment and (SNAP). EPA SNAP affects the selection
appliance manufacturers are exploring and use of alternative refrigerants in
the potential use of a wide range of HVAC equipment and appliances. In
substances that have good environmental 2010 the EPA proposed that hydrocarbon
and thermodynamic properties as refrigerants be accepted in refrigerating
refrigerants. Unfortunately some of the appliances provided that they met
more environmentally attractive options the requirements of specific product
are also flammable. Selecting alternative safety standards. In addition, they
refrigerants has increasingly become proposed rules regarding identification
a complicating factor in equipment and servicing of flammable refrigerant
design, construction, installation and containing appliances. When adopted,
use. The more widespread use of pure the rules will facilitate the use of
hydrocarbon (HC) refrigerants, flammable hydrocarbon refrigerants in the affected
hydrocarbon refrigerant blends, or halo- residential and commercial appliances.
hydrocarbon blends with flammable
However, fulfilling government
hydrocarbons has further complicated
regulations is only part of the compliance
matters, due to the risk of fire and/or
landscape for HVAC equipment and
explosion associated with their use.
appliance manufacturers. Equipment
The most significant regulation affecting must also comply with safety standards
the use of flammable refrigerants in order to be installed in a workplace or
in appliances is the Clean Air Act, (depending upon the local jurisdiction)
administered by the U.S. Environmental in other facilities. Retailers, insurers and
Protection Agency (EPA), under its other parties may also require evidence
Significant New Alternatives Policy of compliance with safety standards.
page 2

3. Executive Summary: Revisiting Flammable Refrigerants
In the U.S., Underwriters Laboratories • ANSI/UL 1995, Standard for Safety for
(UL) is the principal standards developer Heating and Cooling Equipment
addressing electrical appliance and HVAC
• ANSI/UL 484, Standard for Safety for
equipment safety. UL standards are part
Heating and Cooling Equipment
of an overall safety system of coordinated
standards and codes to facilitate safe • ANSI/UL 474, Standard for Safety for
installation and use of equipment. They Heating and Cooling Equipment
complement the electrical installation • UL 984, Standard for Safety for
requirements of the National Fire Refrigerant Motor Compressors
Protection Association (NFPA), notably the
National Electrical Code © (NFPA 70), and • ANSI/UL 60335-2-34, Standard for
mechanical refrigeration requirements Household and Similar Electrical
of the American Society of Heating, Appliances, Part 2: Particular
Refrigerating and Air-Conditioning Requirements for Motor-Compressors
Engineers (ASHRAE), Standards 15 and 34. (The technical white paper provides
The following are standards and detailed information about each of these
codes where the use of flammable standards and their current status.)
refrigerants is either already addressed Much experience has been gained in
or will be addressed therein: recent years regarding the safe use of HCs
• ANSI/ASHRAE Standard 34, Designation and other flammable refrigerants. During
and Safety Classification of Refrigerants this time, the reduction in use of ozone
depleting substances and drive toward
• ANSI/UL 2182, Standard for greater energy efficiency continues. When
Safety for Refrigerants responding to these challenges, it is
• ANSI/NFPA 58, Liquefied important that all stakeholders in the U.S.
Petroleum Gas Code product safety system fully examine the
potential impact of the use of flammable
• ANSI/ASHRAE Standard 15, Safety
refrigerants, and take the necessary
Standard for Refrigeration Systems
steps to ensure their continued safe use
• ANSI/UL 207, Standard for Safety for in HVAC equipment and appliances.
Refrigerant-Containing Components
To download a copy of the technical
and Accessories, Nonelectrical
white paper or learn more about
• ANSI/UL 250, Standard for Safety for related UL standards, testing and
Household Refrigerators and Freezers certification services, visit www.
uluniversity.com/thoughtleadership.
• ANSI/UL 471, Standard for Safety for
Commercial Refrigerators and Freezers
page 3 Copyright © 2011 Underwriters Laboratories Inc. All rights reserved. No part of this document may be copied
or distributed without the prior written consent of Underwriters Laboratories Inc. 01/11 BDI 110103-5