IIR document

Characteristics of refrigerant leaks from small HVAC&R systems.

Number: pap. n. 1108

Author(s) : PATEL V., ABU-HEIBA A., MILLER W., et al.


Reduced use of high global warming potential (GWP) hydrofluorocarbon (HFC) refrigerants is desired. However, many lower-GWP alternatives are flammable, some of higher flammability levels, or A3, and others of lower flammability (A2 or A2L). Safety standards for A2 and A3 flammable refrigerants, including the International Electrotechnical Commission (IEC) standard IEC 60335-2-40 calculate maximum flammable refrigerant charge limits using a fixed 4-minute leak time based on the time to leak 150 g of CO2 through a capillary tube. Actual refrigerant leak times depend on the equipment type, leak location, leak orifice diameter and equipment operation condition (on or off). Five systems were installed in test chambers with leak quantities and rates measured by tracking total system weight during the leak event. Among the major results were that almost all of the system charge was shown to escape the units, >80% within the first 10 minutes.

Available documents

Format PDF

Pages: 8


  • Public price

    20 €

  • Member price*


* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).


  • Original title: Characteristics of refrigerant leaks from small HVAC&R systems.
  • Record ID : 30026068
  • Languages: English
  • Source: Proceedings of the 25th IIR International Congress of Refrigeration: Montréal , Canada, August 24-30, 2019.
  • Publication date: 2019/08/24
  • DOI: http://dx.doi.org/10.18462/iir.icr.2019.1108


See other articles from the proceedings (632)
See the conference proceedings