Australia’s devastating 2019-20 bushfire season has brought attention to the importance of indoor air quality, according to Distinguished Professor Lidia Morawska from Queensland University of Technology. As a physicist with over twenty years of experience in air quality, Morawska’s research on the SARS outbreak in 2003 led her to believe that more focus on building ventilation and protecting indoor air quality was needed. However, funding for this research was scarce until the COVID-19 pandemic and Australian bushfires put air quality and ventilation in the spotlight.
With the pandemic highlighting the importance of airflow and clean indoor air, Morawska and a group of 36 experts on air quality and aerosols convinced the World Health Organisation (WHO) to recognize airborne transmission of the coronavirus. This led to their advocacy for adequate indoor air quality in homes, schools, and public spaces. In a new Insights paper published in Science, Morawska collaborated with 42 other scientists to call for the introduction of national indoor air quality standards for public buildings. They proposed maximum levels for carbon dioxide, carbon monoxide, and fine particulate matter, as well as an ideal ventilation rate per person.
Setting indoor air quality standards for public spaces is a complex endeavor due to the diverse range of pollutants present indoors. These pollutants come from various sources such as natural-gas boilers, wood-burning stoves, building materials, paint, and even humans themselves. Additionally, indoor air quality monitoring is not as prevalent as outdoor air monitoring, making it challenging to assess and maintain good indoor air quality. The proposed metrics in the paper provide a way to measure indoor air quality and ventilation quality, with the goal of diluting and removing pollutants at a higher rate than they are produced.
Morawska and her colleagues proposed a CO2 concentration level of 800ppm, PM2.5 levels based on WHO guidelines, and suggested ventilation rates for occupied rooms. Achieving these standards may require costly retrofits or redesigns of public buildings, but the long-term benefits to public health, well-being, and productivity are likely to outweigh the initial investment. The call for indoor air quality standards is aimed at ensuring that the air people breathe in public buildings is clean and safe, especially in light of recent events such as the COVID-19 pandemic and Australian bushfires that have brought the importance of indoor air quality to the forefront of public awareness.