SNAP: Hydrocarbon refrigerants rule explained

SNAP: Hydrocarbon refrigerants rule explained

On 2 February 2012, Margaret Sheppard from US Environmental Protection Agency and leader of the Significant New Alternatives SNAP: Hydrocarbon refrigerants rule explainedPolicy (SNAP) Program, gave a webinar on the SNAP hydrocarbons rule to be enforced in the USA from 21 February 2012. Here is a summary of the key messages from this presentation organised by the GreenChill partnership.

Early December 2011, the EPA announced the SNAP ruling, setting out the requirements for the use of hydrocarbons in commercial and household refrigeration equipments.

This decision complies with the SNAP purpose of providing choices of substitutes for ozone depleting substances and technologies while minimising new environmental or health risks (section 612 of the Clean Air Act).

The commercial refrigeration stakeholders should particularly be interested in the SNAP as the Section 608 requirements for recovery of refrigerant apply to hydrocarbon refrigerants.

What the SNAP HC rule covers

The rule allows the use of 3 hydrocarbon refrigerants under certain conditions:

  • Propane (R-290) for food retail refrigeration, new stand alone units only (eg.: new self-contained freezers, refrigerators and coolers). This does not apply to vending machines and rack systems.
  • Isobutane (R-600a) and R-441A (“HCR-188C”) for new household refrigerators, freezers and refrigerators/freezers.

Also, the rule enables supermarkets to buy new refrigerators and freezers using propane.


The EPA recommends to train service technicians in proper handling of flammable refrigeration and to check with the local fire marshal before buying equipment with hydrocarbons.

In addition, if you install service port, it is advised to put on fitting that differs from the one for non-flammable refrigerants (eg.: diameter different by at least 1/16 inch / 16mm, or reversed thread direction).


  • The rule will be effective from 21 February 2012 on, and applies to new equipment only and not to retrofitting equipment designed for other refrigerants.
  • These refrigerants must be used in equipment meeting all requirements in supplement for flammable refrigerants in Underwriters Laboratories (UL) Standards:
    UL 471 for commercial refrigerators and freezers (supplement SB),
    UL 250 for household refrigerators and freezers (supplement SA).
  • The charge size limit is: 150g for retail food equipment, 57g for household equipment.
  • Labelling as per UL 471, SB6.1.2 to SB6.1.5, except warning statements letters must be at least 6.4mm (1/4 inch) high.
  • 5 permanent warning labels are required: on evaporator, near machine compartment (2), on exterior, near exposed tubing.
  • Pipes, hoses and services port(s) must be marked with red (Pantone Matching System #185 -red paint, plastic sleeve, tape…), which must extend at least 2.5cm (1 inch) from the compressor.
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