BK researchers participate in landmark Science paper on indoor air quality

News - 04 April 2024 - Communication BK

BK professors Philomena Bluyssen and Atze Boerstra joined forces with a global network of 37 fellow experts on the indoor environment. Their collective paper, published in Science, calls for improved monitoring and regulating of Indoor Air Quality (IAQ) in public spaces. It unequivocally states that “mandatory standards would result in immense benefits to the health and productivity of people around the world.”

This publication is a call to action for governments and agencies to develop, legislate and enforce IAQ standards. Atze: “Traditionally, governments have regulated outdoor air. But inhabitants of industrialized countries now spend more than 90% of their time indoors.” As a result, indoor pollutants have major consequences for our long-term health. Philomena: “For example, we now know that tiny airborne particles can pass directly from lungs to bloodstream, where they cause all kinds of diseases.” And indoor air is also a prime transmitter of pathogens, as demonstrated by the COVID-19 pandemic.

Governments have regulated outdoor air, but [we] now spend more than 90% of our lives indoors.

Atze Boerstra

Where to start

According to the authors, initial regulations should focus on pollutants which are relatively easy to measure and indicate broader health concerns. PM2,5 (airborne particles) fit these criteria, while monitoring levels of CO (carbon monoxide) remains vital in developing economies. In addition, a high indoor CO2 level indicates overcrowding and a lack of ventilation, and thus an increased risk of spreading pathogens. Ventilation is a vital countermeasure, augmented by filtering and cleaning technology where necessary. Atze points out: “Due to poor outside air quality in many cities, mechanical ventilation will remain essential.” And Philomena: “The type of ventilation is critical. Displacement ventilation for schools, personal ventilation for offices… just opening a window is not good enough.”

Philomena examined different types of ventilation and their effectiveness in the context of the COVID-19 pandemic. (Dutch audio)

The hurdles to overcome

The authors point to several challenges in enforcing IAQ standards. For example, a main source of indoor pollutants is human breathing, which is difficult to control. Monitoring IAQ is also highly complex, since every room serves a different function and thus has its own difficult-to-predict fluctuations in pollutants. And new regulations will always be resisted by industries who incur costs or require strategic change. Atze: “For example, the recommended level of ventilation for existing nightclubs and cafes is currently set at 2.1 litres of clean air per person per second, even though the World Health Organisation recommends at least 10 to avoid infections.” Finally, the authors acknowledge that IAQ standards may have economic, cultural, and political implications for certain regions. In such cases, compromises might be unavoidable.

The type of ventilation is crucial… just opening a window is not good enough.

Philomena Bluyssen

The time to act is now

While these obstacles are acknowledged, the paper asserts that the benefits of IAQ standards will far outweigh the costs. Data clearly show the devastating effects of air pollution on the financial and physical health of society, and the authors are fighting those effects. Philomena is part of the Pandemic & Disaster Preparedness Centre, the programme P3Venti (Pandemic Preparedness and Ventilation), and a national project on mobile air cleaners at schools. Atze is part of the nationwide collaboration MIST (Mitigation Strategies for airborne infection control). “And I am a member of NEN and CEN indoor climate committees, which influence policy across Europe.” Therefore, this Science publication reflects the ongoing efforts of Philomena, Atze, and their 37 colleagues to develop technology, research air quality, and advocate for IAQ standards. 

More information

  • The Pandemic & Disaster Preparedness Centre is part of the Convergence collaboration between TU Delft, Erasmus University, and Erasmus Medical Centre. Read more about them on their website.
  • Read more about the programme P3Venti on their website.
  • Read more about project MIST on their website.
  • This paper follows up on a 2021 publication in Science, where these same 39 experts advocate for increased and improved ventilation in the context of the COVID-19 pandemic.