Design
because it builds up condensation in drip trays and the coils have fine fins . This is where we get a build up of biofilm where pathogens can thrive . In addition , these coils get dirty , block up and cause a poor heat transfer surface and have to be regularly cleaned .
EMERGING TECHNOLOGY USED IN HOSPITALS COULD HOLD THE KEY For many years , particularly in the US , hospitals made use of ultraviolet germicidal irradiation ( UVC-GI ) to kill pathogens which caused hospital acquired infections ( HAIs ) to spread in the air conditioning systems . The technology has proved itself especially effective with UVC GI lamps used in air handling plants reducing HAIs by up to 70 %.
Refinement of the technology now makes it suitable for commercial use and one of South Africa ’ s major banks has already retrofitted all the air handling units for some of their larger offices around the country .
The bank was looking for a way to protect and reassure their staff when they returned to the office after working remotely for many months . They investigated various technologies and found UVC to be a well proven technology , and one which did not require any system design changes . Multiple sample swab tests were done on the coils and drip trays before and after installation to check the microbial count which indicated just how effective UVC GI lamps are in this application .
The installation of UVC GI lamps requires no modifications to the existing system design and can be retrofitted into air handling units . In the event of air handling units not having sufficient space , they are installed within the ducting , causing little to no system downtime .
While some may be regarded as emerging , technologies like UVC GI , needlepoint bipolar ionisation , photocatalytic oxidation and HEPA and electrostatic filters can be very effectively used to deliver high quality air to buildings in the most compromised of areas . Each application needs to be carefully assessed , but in the majority of instances improved IAQ can be achieved without major changes and at relatively low capex and opex when we consider a basket of options now available .
For property owners looking to differentiate themselves in a severely downturn-market , offering indoor air quality that will slash the chance of airborne contagions is a low risk , high return solution . For business owners looking to offer the safest possible environment for their most valuable asset – their team – providing the best air to breathe should be the minimum requirement . RACA
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RACA Journal I September 2022 www . refrigerationandaircon . co . za