Research Projects

1. JRAIA Risk Assessment Project for safe use of flammable refrigerants - Overview

In order to tackle the mitigation of global warming, there is a call for alternative refrigerant with lower GWP than currently used in non-A5 countries. However, most of the refrigerants proposed as the alternatives are classified as lower flammability class (A2L).


In Japan, the government, academic sectors and RACHP industry swiftly cooperated for the safe use of A2L refrigerants together under a project supported by New Energy and Industrial Technology Development Organization (NEDO) and greater contribution to the mitigation of global warming as soon as possible. Aims of the project are


  1. Acquire relevant base data
  2. Review of risk assessment
  3. Issue of the report

As a part of the national project, JRAIA has been conducting the risk assessment since 2011 in accordance with ISO/IEC guide 51. Safety evaluation working groups have been established to carry out the JRAIA’s project for specific product types. The working groups consist of experts from JRAIA member companies and researchers from academic sectors of expertise.


Actions to phase down HFCs have been started sector by sector in Japan by considering not only environment performance but also safety, energy efficiency and economic feasibility known as “S+3E” concept.



1.1 Working Groups for A2L refrigerants

Outline of the assessment procedure can be found in the document (linked here).
Outcome of seven WGs for specific product types in the project can be found in the documents (linked below).



JRA standards and guidelines for A2L refrigerants are also available.


The documents below are specific requirements for particular product types and it’s guideline of design construction for ensuring safety against refrigerant leakage;
[ Refrigerant leak detector and alarm ] JRA 4068T:2016
[ Split AC (Light commercial) ] JRA 4070:2016 / JRA GL16: 2016 (Japanese version only)
[ Chiller ] JRA GL15: 2016R (English version of the document will be published subsequently)
[ Facility AC ] JRA 4073:2016 / JRA GL19: 2016 (English version of the documents will be published subsequently)
[ Refrigeration ] JRA 4072:2016 / JRA GL18: 2016 (Japanese version only)


Latest studies of WGs were reported at the International Symposium on New Refrigerants and Environmental Technology in December 2016. As of April 2017, the risk assessment for MiniSplit AC (Residential) and Sprit AC (Light commercial) have been completed (the rest are still ongoing).



1.2 Research Committee for the Risk Assessment of Mildly Flammable Refrigerants

JRAIA is a member of the committee organized by Japan Society of Refrigerating and Air Conditioning Engineers (JSRAE). Results of the studies can be found in JSRAE website.



1.3 Current status of Risk Assessment for safe use of A3 Refrigerants

JRAIA has launched new working groups in 2016 to tackle risk assessment of safe use of flammable (A3) refrigerants such as R290 (Hydrocarbon). Progress of the study will be announced shortly.



2. Useful links relate to JRAIA’s research projects

The International Symposium on New Refrigerants and Environmental Technology 2014 jsrae