Table 3.7.

Case studies on the influence of indoor ventilation rate on health outcomes

Godish and Spengler (1996)	Increasing the ventilation rate up to 10 l/s per person may be useful in reducing the prevalence of SBS symptoms and occupant dissatisfaction with air quality. The use of ventilation as a mitigation measure for IAQ problems should be dealt with factors that may limit its effectiveness
Seppanen et al. (1999)	Ventilation rates below 10 l/s per person in different building types were associated with significant worsening in one or more health or perceived air quality outcomes. Some studies determined that increasing ventilation rates above 10 l/s to ~20 l/s per person significantly decreases the prevalence of acute health symptoms or improvement in the perceived air quality. The SBS symptoms continued to decrease significantly with decreasing CO2 concentrations below 800 ppm
Wargocki et al. (2002, 2004)	Ventilation rates below 25 l/s per person increase the risk of acute health (SBS) symptoms, increase short-term sick leave, and decrease productivity
Mendell and Heath (2005)	No substantial evidence on the causal relationships between indoor pollutants or thermal conditions in schools and the performance of students. Suggestive evidence links low ventilation rates in buildings to decreased performance in children and adults
Seppanen et al. (2006)	A 1–3% improvement in average performance was associated with an increase in ventilation rate by 10 l/s per person. The performance increase per unit increase in ventilation was more substantial with ventilation rates in the range 15–17 l/s per person, and almost negligible with ventilation rates over 45 l/s per person
Li et al. (2007)	Strong evidence of the association between ventilation, air movements in buildings, and the transmission/spread of infectious diseases. Data insufficiency to define the ventilation rates that can reduce the spread of infectious diseases via the airborne route in hospitals, schools, offices, homes, and isolation rooms. Overcrowding is a risk factor related to the ventilation of buildings and also infection transmission via direct contact
Fisk et al. (2009)	Reduction in ventilation rate from 10 to 5 l/s per person led to increased prevalence of SBS symptoms by ~23% (12–32%). Increase in ventilation rate from 10 to 25 l/s per person led to the decreased prevalence of acute symptoms by 29% (15–42%)
Sundell et al. (2011)	Ventilation rates, up toper person, were associated with reduced prevalence of SBS symptoms in offices. Ventilation rates in homes above 0.5 ACH are associated with a reduced risk of allergic manifestations among children in a Nordic climate