A group of international experts, including QUT Professor Lidia Morawska, has developed a blueprint for national indoor quality standards for public buildings. The experts focused on setting standards for three key indoor pollutants – carbon dioxide (CO2), carbon monoxide (CO), and PM2.5 particles that can penetrate deep into the lungs and bloodstream, as well as ventilation rates. Professor Morawska, known for her early recognition of airborne transmission of Covid-19, continues to emphasize the importance of adequate indoor air quality for public spaces, noting that most countries lack legislated indoor air quality performance standards.
The proposed standards aim to be implementable by designing new buildings to meet the criteria or retrofitting existing structures to comply. Professor Morawska advocates for the use of CO2 sensors as a proxy to measure pathogens and contaminants during occupancy in public spaces, emphasizing the importance of monitoring and maintaining clean indoor air. The group suggests a CO2 concentration level of 800ppm as a baseline, considering the increasing outdoor levels due to emissions exceeding removal. Additionally, they propose adopting WHO air quality guidelines for PM2.5 as a basis for indoor air quality standards, with a shorter averaging time to align with typical durations people spend in public spaces.
The experts emphasize the need for mechanical ventilation systems in public buildings to effectively remove and dilute human-generated pollutants at a higher rate than their production, preventing indoor air contamination. They highlight existing technologies for measuring ventilation rates in modern buildings and stress the significance of considering the number of occupants and their activities in determining adequate indoor air quality. The experts suggest practical ventilation standards such as clean outside air or recirculated air to the entire occupied zone, avoiding direct airflow between individuals. They also recommend additional measures like air cleaning and disinfection to reduce the need for increased outdoor air supply, which can place a heavy energy demand on buildings.
Developing appropriate indoor air quality standards and implementing effective ventilation systems can lead to significant social, economic, and health benefits for individuals using public spaces. Professor Morawska asserts that while there may be initial costs associated with meeting these standards, the long-term advantages in terms of public health, well-being, and productivity will outweigh the investment. By focusing on practical solutions such as CO2 monitoring, adherence to WHO guidelines for PM2.5, and proper ventilation strategies, public buildings can ensure cleaner indoor air for occupants, reducing their exposure to harmful pollutants and pathogens.
In conclusion, the blueprint for national indoor quality standards for public buildings presented by international experts, led by QUT Professor Lidia Morawska, outlines key recommendations for addressing indoor pollutants and ventilation rates. These standards aim to be implementable in both new and existing buildings, emphasizing the importance of maintaining clean indoor air for public spaces. By utilizing CO2 sensors, adopting WHO guidelines for PM2.5, and ensuring efficient ventilation systems, public spaces can enhance indoor air quality and promote the well-being and productivity of occupants. While initial costs may be incurred, the long-term benefits in terms of public health and economic advantages are expected to outweigh the investment. By prioritizing clean indoor air standards, public buildings can create healthier environments for all individuals.
