| VENTILATION compared with 2015 (the target was previously 80%). Also, as of 1 January 2027, the proposal would ban split air conditioning and heat pump equipment with a capacity of more than 12kW that employs F-gas with a GWP of 750 or above. The new proposals have raised mixed concerns,10,11 in industry circles, with a key challenge acknowledged by both the EC and the industry being the skills shortage for the safe and effective installation of low-GWP refrigerants; the new EC proposals would require EU countries to expand their certification and training programmes. In the UK, the trend of GWP gas emissions resulting from fluorinated gases, as shown in Figure 2, has generally echoed that of EU emissions, as illustrated in Figure 1. There are suggestions that a revision of the UK F-gas regulations is in the pipeline, but neither the scope nor timetable is known. Refrigerants are classified according to toxicity and flammability by BS ISO 817:2014+A2:2021.12 The toxicity of refrigerants is divided into two groups: class A (lower chronic toxicity) that have an occupational exposure limit of 400ppm or greater; and class B (higher chronic toxicity) that have an occupational exposure limit of less than 400ppm. Refrigerants are also assigned to one of four classes (1, 2L, 2 or 3) based on lower flammability limit (the minimum percentage in the air that is tested as flammable), the maximum burning velocity, and the heat of combustion (class 1 being tested as no flame propagation through to class 3, higher flammability12). The classification 2L was most recently added to better accommodate the increasing use of low-GWP HFCs and HFOs, as otherwise they were simply categorised as class 2 (now known as flammable) as 2L, they are designated lower flammability. As reported in last months CIBSE Journal,13 recent tests have reinforced the understanding that A2L refrigerants are difficult to ignite, have slow flame speed and low heat of combustion, and can be safely applied with proper designs and installations. R32, designated as an A2L refrigerant, is a well-established refrigerant with a lower GWP (of 675), zero ozone depletion potential (ODP), and lower flammability. It was initially mainly used in blended refrigerants, notably in equal parts with fire suppressant R125 to form R410A. Around 10 years ago, small R32 compressors were developed for the Japanese market and their use has subsequently spread globally, particularly in applications that would have previously used R410A. R32 has operating characteristics that are similar to R410A, but it requires a lower refrigerant charge and can provide significant efficiency gains.14 As a single component fluid, with a single carbon molecule, there are no glide or fractionation issues that exist with blended (zeotropic) gases and, as a single component refrigerant, it has a single pressure-temperature relationship that eases the understanding of performance in the field, and is more straightforward 120 100 80 60 40 20 0 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 unsaturated HFCs, or hydrofluoroolefins (HFOs) such as R1234yf (GWP = 4) as an alternative to R134a (GWP = 1,430); lower GWP HFCs, such as R32 (GWP = 675) as an alternative to R410A (GWP = 2,088) in split air conditioning, variable refrigerant flow (VRF), and heat pump applications; and R448A (GWP = 1,273), which is typically used to displace R404A (GWP = 3,922) in commercial refrigeration has grown appreciably. In the EU, refrigeration, air conditioning, heating and other heat transfer fluids account for the majority of F-gas use, estimated4 as 63% in 2019. A significant share of the shift in warming impact of HFCs has resulted from the reduced use of key high-GWP HFCs and HFC blends such as R134a, R404A and R410A and while the amount of HFC contained in imported products and equipment has remained practically constant, the GWP of these HFCs dropped by 33% owing to increased application of lower-GWP HFCs. In work5 undertaken for the EU, it is noted that there may be some undesirable environmental effects from the application of HFOs as a low-GWP alternative, related to the generation of environmentally persistent and accumulative trifluoroacetic acid (TFA) in the atmosphere, which will require further investigation. There has also been a shift to natural alternatives such as CO2 (GWP = 1), propane (GWP = 3) and ammonia (GWP = 0) that are not restricted under the F-gas regulations. As a result of the HFC phasedown, and the consequent restricted supply, prices for higher GWP HFCs have, by design, seen significant increases. In contrast, prices for alternatives that are not covered by the phasedown have largely remained more stable, making climate-friendly technologies more competitive. However, it was recently reported that HFCs still represent around 90% of F-gas emissions in Europe,6 contributing 2.5% of the EUs total greenhouse gas emissions. (Internationally, F-gases are among the fastest growing greenhouse gases, largely as a result of increasing demand for refrigeration and air conditioning, especially in developing economies.). The analysis5 undertaken on behalf of the EU indicates that the 2030 F-gas goals may not be fully reached under the current regulation. So, in April 2022, and coincident with the publication of the Intergovernmental Panel on Climate Changes (IPCC) 6th assessment report,7 the European Commission (EC) made a proposal8 to transform the F-gas Regulation, upping the bar so as to reduce the amount of HFCs on the market by 98%9 by 2050 Emissions (Mt CO2 eq) CPD PROGRAMME Year HFCs PFCs Unspecified mix of HFCs and PFCs NF3 SF6 Figure 1: F-gas emissions in the EU27+UK from 1990 to 2019 (Source: see reference ) 5 52 June 2022 www.cibsejournal.com CIBSE June 22 pp51-54 198 Daikin.indd 52 27/05/2022 16:59