Feature
Ionisation : Bipolar ionisation creates ions out of oxygen which attach themselves to microparticles , bacteria , and viruses , which has been used in the healthcare setting for many years and been effective at reducing viruses such as Covid-19 and SARS in the past . The ions are over 99 % effective at deactivating a virus ’ ability to infect a victim , as the technology has improved in recent years , reducing the cost of installing a unit . Ozone : Ozone is a reactive gas that kills bacteria and viruses , which can be used for disinfection of unoccupied spaces if it ’ s handled properly by a professional cleaning company . But it ’ s generally ineffective for continuous use in HVAC systems .
Clive Donnelly , mechanical engineer at BD & O Group , lists the two most popular types of air purifiers as bipolar Ionisation ; and UV-C radiation . “ Both have been around for a long time . UV-C works well but has its drawbacks and can be dangerous . Bipolar ionisation has proven successful over the last 25 years and was tested to great affect with SARS CoV-2 virus simulations . It has also been successfully used in the food industry to reduce bacteria from a space .
“ Filters and UV-C only treat the air that passes through them , so they are dependent on good airflow , while bipolar ionisation treats the air which then goes into the space to improve the indoor air quality ( IAQ ). Consequently , based on the draw backs of UV-C , we recommend bipolar ionisation to our clients .”
SHIFT TO CLEAN AIR TECH CAN REDUCE ENERGY COSTS BY UP TO 25 % As commercial property owners and managers look for every available competitive edge to attract and retain good tenants , great IAQ has become more than just a compelling sales point . UVC GI disinfection systems are not only delivering cleaner , healthier air , but can reduce energy costs by up to 25 %.
“ South African commercial property is struggling to regain Covid losses as owners and managers face a ‘ Catch-22 ’. With weak property demand and oversupply , finding compelling differentiation such as a healthier work environment , must be weighed up against the investment required to install or upgrade IAQ systems . When that investment produces a rapid ROI the decision to move to UVC GI becomes a simple one ,” says Edward Hector , MD of the SFI Group .
The UV-C wavelength has more than twice the energy of other UVs and is easily absorbed by organic substances , rapidly destroying molecular bonds . This means UVC GI can be used to safely eliminate and prevent the build-up of organic material on coils , drain pans , and interior air-handling surfaces . It improves airflow and can maintain and even return heat-transfer levels to ‘ as-built ’ capacity , delivering solid improvements on HVAC system efficiencies . Clean systems reduce odours , as well as allergens or pathogens in airstreams . They help sustain design temperatures
30
RACA Journal I February 2023 www . refrigerationandaircon . co . za