Vienna, Austria, 01 July 2026 — The impact of air pollutants and extreme temperatures on health is undisputed. In research studies, concentrations and temperatures are usually measured outdoors or in relation to outdoor air. However, people spend by far the largest part of their time indoors.
Indoor spaces are, of course, strongly influenced by the outdoor environment. Otherwise, it would not be possible to study the effects of external environmental conditions. Yet every indoor space is different, and this variability can introduce considerable measurement uncertainty, potentially leading to an underestimation of the true health effects.
For this reason, it is important to better understand which factors, beyond the outdoor environment, influence indoor air quality and the indoor climate. Given the diversity of indoor settings, large numbers of measuring devices are needed. To keep studies affordable and scalable, these devices must rely on low-cost sensors.
K-HEALTHinAIR, a versatile EU co-funded research project involving partners from Spain, Portugal, the Netherlands, Norway, Ireland, Germany, Poland and Austria, set out to investigate how these low-cost sensors perform, what their strengths and weaknesses are, where their limits lie, and how they can be further optimised under different climatic and situational conditions.
Each partner selected several settings, such as hospitals, student residences, metro stations, market halls, lecture rooms and company canteens, to test different sensors. Hanns Moshammer, head of the working group at the Medical University of Vienna, explains: “We selected homes and schools. In my own apartment, I used four measuring devices from three manufacturers in parallel. For me, as a physician and epidemiologist, it was important to understand how reliable the data were, which interfering factors occurred, and how the different devices varied. Most of the data were plausible and responded to user behaviour and environmental influences. We are now analysing the data in detail and linking them with the health data collected at the same time.”
In addition, the project team collected other measurement data, such as concentrations of fungal spores and bacteria, and tested different measures to improve indoor air quality. Moshammer adds: “It is hardly surprising that filters filter. Nevertheless, I was surprised by how well this worked, at least with regard to fine particulate matter.”
The effect of activated carbon filters on volatile organic compounds, particularly formaldehyde, which was found to be too high in two Austrian apartments, still needs to be examined in more detail. However, simpler measures, such as awareness-raising and changes in ventilation and smoking behaviour, also proved to be highly effective.
For more information about K-HEALTHinAIR and to access project resources, visit: k-healthinair.eu.