Air pollution continues to represent one of the greatest critical issues for people’s health. A figure also confirmed by the annual report “Air quality in Europe – 2019 report“, Published by the European Environment Agency (EEA) *1 , which highlights that in 2017, 44% of the urban population of the EU-28 countries was exposed to concentrations of PM particulate matter10 higher than the values recommended by the World Health Organization (WHO), a percentage that rises to 77% with reference to PM2.5. Although it is generally believed that air pollution only concerns the external environment and that this phenomenon is drastically reduced, if not absent, in confined spaces, the scientific data collected in the last thirty years highlight the opposite.
Andrea Casa, Chairman of the International Affairs Committee and member of the Board of Directors of NADCA (National Air Duct Cleaners Association) the most important and prestigious Association in the world on the issues of hygiene of air systems e President Emeritus of AIISA (Italian Association of Aeraulic Systems Hygienists) strong comments: “The emergency caused by COVID-19 has significantly increased the collective sensitivity towards the relationship between outdoor and indoor pollution” in and goes on “Specifically, awareness has increased on how air handling systems can play an active role in the delivery of SARS-CoV-2 within confined spaces. If we consider the workplace, air quality becomes a determining factor in protecting people’s health and safety and, in this sense, eliminating the risks of contamination by viruses, fungi and bacteria, in full compliance with current legislation, is now an essential imperative in“.
The recent ISS COVID-19 Report, No. 5/2020 Rev. 2, published on 25 May, indicates the procedures to be implemented to ensure the healthiness of the air in closed environments, based on the number of workers, first of all the exclusion of the air recirculation circuit, to avoid possible transport of the virus and other pathogens in the air. However, compared to the previous version, the new document is more in line with the Italian plant engineering reality since it takes into account how essential, especially in summer, this function is essential and cannot be removed without compromising the performance of some systems. This would involve variations both in terms of temperature and humidity, factors that make the environments safe and comfortableindoor in the hottest season. In other words, these systems, in order to be able to cool and dehumidify the air, should both take outside air and use the air that has already been treated.
“The solution to keep the recirculation circuits active and, at the same time, ensure hygiene and safety conditions inside the air-conditioned rooms, lies in careful Aeraulic Risk Assessment, a fundamental tool for implementing an effective risk management and mitigation system, including that deriving from the spread of SARS-CoV-2” He declares Andrea Casa who continues “The risk linked to COVID-19, in fact, depends on a plurality of factors, which is not reduced to the simple presence or absence of air recirculation. The function of this document is to strengthen the specific protocols to combat and contain COVID-19 adopted by individual companies, effectively protecting the health of workers and objectively demonstrating to the competent authorities that they have followed a line of conduct based on compliance with the rules and diligence “of the good father of a family” and concludes “In the evaluation, the structure of the systems, their integrity and state of operation, as well as the environmental conditions inside and outside the buildings and those relating to the type of people who live in them also take on importance.no. In this sense, the Document Management Plan provides for all the measures and precautions to be taken to keep the recirculation circuit running, without dangers.“.
In this regard, there are technologies that make it possible to further raise the level of protection: thanks to a remote control of the Air Handling Units and the aeraulic ducts, it is possible to monitor the quality of the air supplied by the system and accurately record the timing of contamination formation, in favor of a predictive analysis on the hygienic state and operating conditions of HVAC systems.