Abstract
We investigated nitrogen dioxide (NO2) concentrations in the indoor and outdoor air of a home from March 2000 to January 2001.
NO2 concentrations in the indoor environment, where non-combustion, electrical heating systems were used, exceed 60 ppb during four consecutive days in both December and January. Overall, indoor NO2 concentrations exceeded the upper limit of Japan's Environmental Quality Standards on 32% of the measurement days.
From winter to early spring gas equipment for cooking was used for many hours, but windows were seldom opened. A positive correlation was found between the NO2 concentrations in the kitchen and the consumed amount of city gas.
