Introduction by Croakey: In Belgium, all public buildings are required to have visible air quality monitoring as part of new laws aimed at improving improve indoor air quality in closed spaces for the public.
However, the growing global push to improve indoor air quality, precipitated by the COVID pandemic, faces many challenges, reports Alison Barrett.
Alison Barrett writes:
Experts gathered in Switzerland and online for the First World Health Organization/Europe Indoor Air Conference on 20 September, with the aim of identifying how to improve the safety of indoor environments.
Organisers said the COVID-19 pandemic had shown the importance of ventilation to mitigate the transmission of respiratory disease, but more widely there was also growing awareness that exposure to pollutants in indoor environments has a substantial impact on health, productivity and performance.
Large numbers of buildings do not have good ventilation or good indoor air quality, and there are multiple other considerations including climate change, energy, comfort, noise and security, the organisers said.
“The focus of the meeting is to consider what is needed at a strategic level to make effective change to improve indoor environments in buildings. We will explore the practical challenges and opportunities for understanding and mitigating poor ventilation in the most cost-effective ways.”
Speakers made wide-ranging calls for action, including urging long-term systemic change to address indoor air quality, collaboration, and more support and investment in research. They noted that addressing indoor air quality is complex with many different pollutants and interactions at play.

However, “we have enough evidence to act”, according to Associate Professor Pawel Wargocki, International Centre for Indoor Environment and Energy, Technical University of Denmark. He said we can start by implementing standards, air quality ratings, controlling airborne threats at the source (for example, by preventing bushfires) and ventilation.
Australia is also grappling with how to progress indoor air quality. A key message of the Senate inquiry into long COVID and repeated COVID infections report and a Clean Air Forum held at Parliament House earlier this year was the importance of safeguarding air quality and ventilation in response to managing COVID-19 as well as other airborne threats.
Bushfires this week in NSW, Tasmania and elsewhere have underscored these concerns, with NSW Health cautioning the public on the hazards of bushfire smoke. Air quality status by region in NSW can be viewed on the NSW Government website.
Holistic approaches needed
Professor Catherine Noakes, Professor of Environmental Engineering for Buildings at University of Leeds, said the short-term actions we can take range from source reduction (such as by using kitchen extraction fans) to maintenance, retrofitting, repairs, increasing ventilation and installing air cleaners.
“It doesn’t have to be difficult, and it doesn’t have to be expensive,” Noakes said.
However, she added that we need long-term systemic change, and collaboration within and across disciplines as well as with other countries. Noakes also called for responsible innovation and stressed the importance of connected approaches.
“We can’t look at indoor air alone, we can’t look at climate alone, we have to put the two together.”
Prior to the conference, Noakes told Health Policy Watch that there is a tension between ensuring a home or office is properly ventilated while trying to save energy and reduce the impact on climate change by improving air tightness and insulation.

In a panel at the conference, Noakes said if done properly “climate change presents an opportunity” to address this tension as we can improve building ventilation at the same time as we make the changes required to buildings to mitigate and adapt to climate change.
Many speakers emphasised that indoor air quality is impacted by outdoor air quality, and thus efforts to improve the outdoor environmental air should also be addressed.
COVID-19
As with the Clean Air Forum, COVID-19 was the stimulus behind the First WHO/Europe Indoor Air Conference.
Regional Director of WHO/Europe Dr Hans Kluge said that indoor air quality is not a new issue or concern, but the pandemic raised the issue and brought it to the front, not only for infection prevention but also for other environmental benefits.
WHO’s Chief Scientist Sir Jeremy Farrar said it will be a missed opportunity if we don’t realise and act on the importance of good quality air.
Kluge told attendees that WHO air quality guidelines – which were revised in 2021 – were being considered for adoption by the European Parliament.
The European Parliament has voted in support of stricter limits and targets for several pollutants by 2035 in alignment with WHO’s guidelines, with the “final shape of the law” under negotiation, according to a 13 September press release from the European Parliament.
However, the WHO’s air quality guidelines do not include infectious agents/airborne pathogens, Wargocki from Technical University of Denmark told the conference.
Belgium example
Legislation was approved at the end of 2022 in Belgium to improve indoor air quality in closed spaces for the public.
Deputy Prime Minister of Belgium and Minister for Social Affairs and Public Health Frank Vandenbroucke told conference attendees that legislation includes guidelines for monitoring indoor air quality, verification of measurements and transparent community.
It is the first step in an ongoing process of air quality assessment, he said, and research must be supported to “define the most efficient regulatory approaches”.

Ghent University’s Associate Professor Jelle Laverge told attendees that as part of this legislation all public buildings need to have visible air monitoring installed.
If we can’t guarantee the quality of indoor air for people, then we can provide them with information about what air quality they can expect, Leverge said.
Some of the main challenges they have experienced include reliance on correct and accurate monitoring devices being sold and bought, people implementing the monitoring strategy are not necessarily experienced with the technology and communication.
Stakeholder involvement is critical, Laverge said.
Evidence and breaking down silos
Noakes commented on the challenges in conducting research on indoor air quality and interventions, especially given the many types of pathogens and particles in the air, making it hard to control for confounding effects.
She suggested that more investment is required for larger population studies.
Kluge reiterated the message of other speakers that “advocacy must be supported by robust data and evidence”, which he said included by “human storytelling”.
Farrar said it is “crucial” for communities and different disciplines to come together to work on improving indoor air quality, and if we do, change will occur at a faster pace.
Further reading
Action on air pollution needed to reduce health impact on communities, by Dr Deren Pillay, Dr Bill Dodd and Professor Bin Jalaludin
Landmark event highlights indoor air quality as important health concern by Alison Barrett
Long COVID inquiry recommends action on clean indoor air by Jennifer Doggett
You can watch the conference here, noting that not all presentations are available.
From Twitter
Information about the study here.
Read the paper here.
See Croakey’s archive of articles on COVID-19