EXPERIMENTS PROBING THE INFLUENCE OF AIR EXCHANGE RATES ON PARTICLES GENERATED BY INDOOR CHEMISTRY

摘要

Investigators have recently reported increases in the concentrations of airborne particles as a consequence of ozone/terpene reactions in indoor settings. The present study was designed to probe the influence of ventilation on these increases in particle concentration as well as on the resulting particle size distributions when both reactants originate indoors. The experiments were performed in two comparable offices. Each contained limonene sources, but only one contained an ozone generator. There was no statistically significant difference in particle concentrations between the offices when the ozone generator was on and the air exchange rate was high (> 10 h~(-1)). However, as the air exchange rate decreased, particle number concentrations in the room containing ozone increased. Furthermore, particulate mass was shifted from smaller sizes into the 0.3-0.5 μm size range. Such changes are of interest since size partially determines where particles deposit in the human respiratory tract. These results illustrate still another way in which ventilation affects health and well being.