Difference of indoor air quality with various scales of office buildings

To maintain indoor environments, large-scale buildings have been managed under the "Law for Maintenance of Sanitation in Buildings (established in 1970)" in Japan. Although the large-scale buildings are managed on the indoor environmental standard,the management statuses for small-scale buildings, for example, office buildings smaller than 3000m ² total floor areas, out of the law are not clear. This study carried out the field measurements of indoor particulate matter, volatile organic compounds (VOC) and airborne microbes both in large-scale office buildings and small-scale ones, and investigated the differences of indoor air quality. As a result, the particle matter concentrations, VOC concentrations and fungi concentrations for the small-scale offices were relatively higher level than the larger-scale ones. It became clear that low air exchange rates and low filtering efficiencies of the air filters in the small-scale buildings could be affect on indoor air quality.