Abstract
To obtain information on harmful volatile organic compounds (VOC) in indoor air of houses, their concentrations were determined by means of solid phase extraction and GC/MS. The removal rate in indoor air were examined by using three kinds of air cleaners equipped with titanic oxide photocatalysts.
The daily variation of VOC concentrations was 14.6% for six days under a sealed condition in a new house. Similar variations (within 20%) were observed for toluene, xylene and trimethylbenzene.
The removal efficiency for total VOC (T-VOC) in indoor air under the sealed condition was dependent on the type of air cleaners, ranging from 36% to 74% per day. In indoor air of an occupied house, the elimination of p-dichlorobenzene (DCB), an insecticide, was also examined by using an air cleaner, which was fitted with a pre-filter and a photocatalytic filter, at a flow rate of 190~310 m3/hr. DCB was eliminated by 41% per day, but the removal rate was lower than that of toluene and xylene.
The cytotoxity of photo-decomposed products collected from the indoor air by solid phase extraction was also examined, but the rate of cell growth during the air cleaner operation was the same as that of blanks, and therefore no cytotoxic effect was found.
