Some 34 technical papers and a keynote speaker focused specifically on CO2 during the quadrennial International Congress of Refrigeration (ICR), sponsored by the International Institute of Refrigeration (IIR). The paper count was a quantum leap above the single-digit number of papers on the topic at past conferences.
The ways offered to make CO2 create cooling were wide ranging, including use as a stand-alone refrigerant and in conjunction with such refrigerants as ammonia, propane, and HFC-404A.