Seventy-one percent of the studied locations were apartments
(from ground floor up till the fifth floor; one subject lived on the
eighth floor), 25% were enclosed houses and 4% semidetached
houses. The bedroom faced the roadside in 38% of the cases (62%
had a backside location). Eighty-three percent of the bedrooms
had double-glazed windows (17% had single-glazed windows).