The performance of residential ventilation systems.

The indoor climate and ventilation were measured in 50 dwellings with various ventilation systems. The health and comfort of people living in the dwellings were studied with a simultaneous questionnaire. The ventilation rates measured with a tracer gas using the decay method varied from 0.1 to 1.2 m³/hm³, with an average of 0.5 m³/hm³. The ventilation rate in the bedroom was usually lower than the mean ventilation rate of the dwelling. The ventilation rates measured in a two-week period with the passive perfluorocarbon method varied from 0.2 to 1.9 m³/hm³, with an average of 0.8 m³/hm³. There was a statistically significant correlation between the ventilation rate and the typical sick building symptoms expressed by people living in the dwellings. When the ventilation rate was low (below 0.3 m³/hm³), people had more symptoms than when the ventilation rate was high (above 0.6 m³/hm³). No such correlation was found between the various ventilation systems and health.