Indoor Air Quality in Healthcare: Evidence and Impact

The science behind our Safe Air 4 All campaign

Overview

Indoor air quality (IAQ) is an important but often overlooked aspect of healthcare. The presence of airborne pathogens, such as SARS-CoV-2 (Covid-19), has been shown to have a significant impact on infection rates and absenteeism among healthcare workers (Riga First Hospital 2024) as well as increasing the number of hospital acquired infections (Brock et al. 2025). Despite this, many healthcare facilities lack adequate ventilation and air filtration measures. To address this urgent issue, Supporting Healthcare Heroes UK (SHH-UK) is launching a campaign to raise awareness of the importance of clean air in healthcare facilities.

Research evidence: Brief summary

Research emphasises the impact of IAQ on health. A UK hospital study detected the presence of SARS-CoV-2 in the air on COVID-19 wards before and after HEPA air filtration was activated, confirming that air filtration plays a critical role in infection control (Conway Morris et al. 2021).  Similarly, a hospital in Riga observed a 27% decrease in staff sickness absence after improving indoor air quality (Riga First Hospital 2024).

Further evidence suggests that a reduction in CO₂ levels correlates with a lower risk of transmission. Iwamura et al. (2024) found a direct linear relationship between indoor CO₂ concentration and airborne transmission risk, highlighting the effectiveness of CO₂ monitoring as a tool to assess ventilation. The British Council for Offices (2023) recommends keeping CO₂ concentrations below 800 parts per million (ppm) to ensure a safe indoor environment. In France, the guidelines state that CO₂ concentrations above 800 ppm require immediate ventilation measures and reduced room occupancy (French High Council for Public Health 2021).

For more information, read our two campaign position statements:

• Why indoor air quality in healthcare settings matters

• Urgent changes needed to infection prevention and control policies