At the advent of the Montreal protocol, R134a has been suggested as an alternate refrigerant to R12. R134a is a high global warming potential gas and needs to be controlled as per the Kyoto protocol. It is reported that there is no single refrigerant or mixture available to satisfy both the ozone depletion potential (ODP) and global warming potential (GWP) issues. In this scenario, the objective of this work was, to develop an eco-friendly refrigerant mixture with negligible ODP and GWP values that is nearly equivalent to R12 in its performance. R123 is a potential refrigerant with very low ODP and GWP values, but due to its high suction specific volume and high boiling point, it has not been considered as an alternate refrigerant to R12. In this work, to overcome the above said problems, R290 has been identified as suitable for combination with R123 in a refrigerant mixture. Using REFPROP for analysis, it was found that the performance parameters for a mixture containing 70% R123 and 30% R290 were near matching with R12. This has been further confirmed experimentally by conducting a base line test with R12 and tests with the new mixture. The flow characteristics of the mixture were compared with R12 and presented. (c) 2007 Elsevier Ltd. All rights reserved.