INCORPORATING COLD CHAIN
ASSOCIATIONS including city centre office buildings , conference centres , exhibition halls , data centres and airports . The industrial sector also found uses for carbon dioxide , particularly in freezing equipment where the highly unusual physical properties of CO2 provide unique benefits in reduced freezing times and improved efficiency . Air cycle systems , which date back to 1844 in the history of refrigeration , have found some niche applications in low temperature freezing but they have not been widely commercialised .
All these successful developments were driven by environmental concerns but at the same time energy was becoming increasingly important , with high costs of electricity occasionally raising the profile of efficiency initiatives . Safety and reliability were also being improved , partly through legislation such as the European Machinery ( Safety ) Directive and Pressure Equipment Directive , partly through national regulations and partly through the relentless increase in product liability litigation , particularly in the US but increasingly seen in other parts of the world .
4 . STATUS REPORT
It is helpful to take stock of the current position across the broad range of technologies that comprise the refrigeration world , including of course air-conditioning and heat pumps . We are 40 years on from
Figure 1 : Ozone Forecasts ( from Salawitch et al , 2022 ) the Vienna Convention for the Protection European f-gas regulations 19 years ago , of the Ozone Layer , the forerunner of the updated 11 years ago and again earlier this Montreal Protocol and we are 33 years on year . It also , eventually , led in the US to the from the Earth Summit in Rio de Janeiro , AIM Act , which entered into force four years the kickstart to the Framework Convention ago . on Climate Change that produced the
The decisive action under the Montreal Kyoto Protocol 28 years ago . This led to the Protocol has reversed the trend of ozone depletion and levels in the Antarctic , where depletion was most severe , and over the whole globe are expected to return to 1980s levels by about 2060 , as shown in Figure 1 . In contrast , NASA estimated in 2009 ( Carlowicz , 2009 ) that by 2065 the ozone shield at mid-latitude in the stratosphere would have reduced to about one third of its 1980 level if action had not been taken against chlorine compounds . This , it was said , would cause sunburn with five minutes and would have resulted in damage to DNA in plants , animals and humans causing a wide range of health problems . This bleak scenario appears to have been averted .
Moves to address the threat of global warming have been less successful so far and we seem to be in grave danger of missing the targets that were originally set as safe limits . It has been much harder to impress the dangers of climate change on the minds of the public and this has translated into a rather weak political response to the scientific evidence of the need for action . The issue is far more complex than the ozone depletion scenario and has been the subject of massive debate about the truth of the scientists ’ claims with misinformation on both sides of the argument leading to confusion and ultimately inaction in the political world .
COLD LINK AFRICA • March / April 2025 www . coldlinkafrica . co . za 11