46
Technical
GLOBAL ADVANCES IN
TECHNOLOGY FOR AIR PURIFICATION
By Peter Mostert , managing director at Filta-Matix
There have been significant recent advances in technology dealing with indoor air quality products – none more so than since the advent of the COVID-19 pandemic . Never before has there been such a global drive to develop technical solutions with almost no limits in funding to combat the Coronavirus disease .
Existing HVAC systems could not simply be upgraded to include HEPA filtration because the fans were not originally selected for the added resistance levels of high efficiency air filters . Engineers and scientists have worked tirelessly to develop technology which could be included into existing HVAC systems without having to make drastic changes in design .
It is fair to say that the global pandemic has evolved into a more managed state , but hospital associated infections and other airborne pathogens will continue to challenge society as a whole .
Exposure to airborne particulate matter on the other hand is associated with a range of adverse effects on human health , including effects on the respiratory and cardiovascular systems , leading to hospital admissions and mortality .
STATISTICAL ENVIRONMENTAL CONTAMINATION Atmospheric air will contain contamination , including :
• Particulate matter ( PM )
• Airborne pathogenic microorganisms
• Pollutants in gas-phase
It is important to note that the testing methods for each of the above pollutants are entirely different and test results depicting efficacy will be limited to the test process in question .
PARTICULATE MATTER TEST METHOD ( PM ) Test methods for ambient air quality relating to particulate matter ( PM ) are often misunderstood and in some instances incorrectly interpreted . There is also a clear and distinct difference in particle counting by size ( micron ) and particle counting by mass (µ g / m ³). The test methods and test results are completely different . ISO 16890 explains the international test standard for air filters and came into effect from 1 July 2018 .
In a recent publication , a supplier of an electrostatic precipitator air purification device published the following test results : ‘ PM2.5 Purification efficacy of 99 %’; and then proceeded to compare the efficacy of the electrostatic precipitator to that of HEPA filters claiming 99.99 % efficiency against particles of 0.3 micron in size during a single pass .
Imagine end users having to navigate and understand complex test methods in order to make informed decisions on products which have an impact on health and safety .
WHAT DOES PM2.5 MEAN ? According to the ISO standard , filters are divided into four fine dust groups according to their filter efficiency :
All images by Filta-Matix
PM 1 These are the same rating parameters used by the : PM 2.5 * WHO ( World Health Organisation ) PM 10 * EEA ( European Environmental Agency )
ISO Coarse
* EPA ( American Environmental Agency )
46
RACA Journal I July 2023 www . refrigerationandaircon . co . za