International. The use of flammable refrigerants such as HC-290 (propane) as an alternative to HCFC-22 in split air conditioning systems for domestic rooms and refrigerators is spreading.
In response to safety concerns, a team at GIZ Proklima uses quantitative risk assessment tools to estimate the severity and frequency of ignition of HC-600a (isobutane) and HC-290 in both systems. Parameters such as leak types and frequencies, flammable volumes and potential sources of ignition were taken into account.
The calculated ignition frequency of both appliances was found to be extremely low (less than one case per million ignitions in household refrigerators over a ten-year period or one event per 100 million in ten years for air conditioners. It was also found that the frequency of secondary fires was ten times lower than that of ignition) which shows that the risk associated with the large-scale application of R290 in splits is negligible.
The study was presented at a recent conference presented in China. It can be downloaded from the website of the International Refrigeration Institute (iir).
