Significantly higher concentrations of fungi were found in dwellings with high relative humidity
(p ¼ 0.03), larger room volume (p ¼ 0.03) and in dwellings located on the second floor or higher
(p ¼ 0.02). Small floor area per person and low air exchange rate were significantly associated with
increased concentrations of bacteria (both p < 0.01). Spring season (p ¼ 0.01), buildings constructed
before the 20th century (p ¼ 0.09) and wooden floor (p ¼ 0.03) were associated with high TIP.
In conclusion, people living in smaller dwellings or in dwellings on upper floors are at higher risk of
microbial exposure. While TIP was affected by some dwelling characteristics, it was mainly influenced by
season.