Every ventilation system, whether it is a commercial or public building or a private home, should be equipped with ventilation filters. Their role is to stop and eliminate various pollutants. They are the basis of safe, clean air indoors. This is the first line of defense against suspended dust, bacteria, viruses, fungi and mold, and other solid particles harmful to health. Are you an HVAC installer? This article will tell you what viruses are transmitted by ventilation and how to clean and filter the air from suspensions and dust in accordance with applicable standards.
Check out the filters for recuperation at the Onninen wholesaler
Types of viruses transmitted by ventilation
The main "culprits" of indoor air pollution are: particulate matter (PM) and aerosols exhaled by users of rooms. They contain bacteria and active viruses, such as the SARS-CoV-2 virus responsible for COVID-19 disease or the influenza virus. The emission of microorganisms hazardous to health is increased by increased respiratory activity, such as sneezing, coughing, rapid breathing or singing. Of course, just being in a room where the air is polluted with viruses does not automatically mean infection and illness.
This is influenced by many factors, in particular the number of sick people in the room, physical activity and susceptibility to illness (age, health, immunity). An additional carrier of active viruses is suspended dust. Proper ventilation helps to remove or at least dilute the viral aerosol, which significantly reduces the risk of so-called cross-infections. However, ventilation can also be a source of viruses that are able to survive in ducts. Their existence is facilitated by dust and moisture on the surface. Microbiological contamination in mechanical ventilation poses a serious threat to human health. They can cause respiratory lung infections and respiratory diseases.
Efficiency of anti-smog filters in ventilation - PN-EN ISO 16890-1 standard
The effectiveness of anti-smog filters against suspended dust of a specific size is specified in the PN-EN ISO 16890-1 standard. An anti-smog filter should retain at least 50% of a given dust (e.g. PM2.5, PM10) suspended in the air.
Instead of using a dust and smog filter, you can install a filter on the air supply or equip the ventilation system with a special box with an anti-smog filter and – optionally – an activated carbon filter, which removes numerous substances from the air, including those causing unpleasant odours from ventilation.
There are also electrostatic filters available on the market, designed for installation on the supply duct. Of course, filters installed in mechanical ventilation systems should effectively stop not only suspended dust, but also external microbiological contamination.
Selecting the right class of filters for ventilation
Outside air is blown into the interior through ventilation. Many anti-smog filters are not able to meet the WHO recommendations for outside air in terms of PM2.5 and PM10 dust concentration. To ensure that people staying indoors have an inflow of safe air, it is recommended to install a filter with the efficiency class intended for PM1 particles, i.e. an ePM1 80% filter in areas with very high dust levels and an ePM1 70% filter in areas with high dust levels. According to industry guidelines and scientific studies, the ventilation system should be supplemented with additional filtration, which can be successfully implemented by portable air purifiers.
The filtration system in an air purifier effectively reduces the risk of spreading droplet diseases. It usually consists of several filters. The pre-filter cleans the air from larger impurities and increases the life of the remaining layers. The HEPA filter captures fine pollutants from the air, including PM2.5 and PM10 dust (smog) and live viruses. The carbon filter neutralizes unpleasant odors and stops volatile organic compounds.
We encourage designers and installers of HVAC systems and other professionals to familiarize themselves with the offer of the Onninen wholesaler. In the categories of ventilation , air conditioning , recuperation and refrigeration, you will find thousands of devices and accessories from renowned manufacturers. We will help you choose the installation elements.
Check out the filters for recuperation at the Onninen wholesaler