acceptable indoor air quality

This study presents a health-centered approach to quantify and compare the chronic harm caused by indoor air contaminants using disability-adjusted life-year (DALY). The aim is to understand the chronic harm caused by airborne contaminants in dwellings and identify the most harmful. Epidemiological and toxicological evidence of population morbidity and mortality is used to determine harm intensities, a metric of chronic harm per unit of contaminant concentration. Uncertainty is evaluated in the concentrations of 45 indoor air contaminants commonly found in dwellings.

This work quantifies the chronic harm caused by long-term exposure to common indoor air contaminants in dwellings located in the global north. Two methods are used to compute DALYs. The first uses incidence data and the second considers toxicological evidence. They are synthesised to produce Harm Intensities, the number of DALYs per person per unit of annual-average concentration the person is exposed to.

The role of ventilation in achieving acceptable indoor air quality is examined in the light of emerging challenges, alternative mitigation strategies and performance indices within the spatial and time matrix of the indoor environment. By considering the source of contaminants, their nature, transportation mechanism and participation in source-sink relationships, several studies have shown that it may not be feasible nor adequate to rely on ventilation alone to attain the desired level of exposure, especially with respect to airborne aerosolised droplets with infectious potential.