DC-2774 (RP-352) -- Analysis of Indoor Air Acceptability Data from a Public Buildings Ventilation Study PDF

Data collected in a Lawrence Berkeley Laboratory study on ventilation in four public buildings included sensory evaluations of indoor environment and of physical and chemical properties of indoor air. This data base was analyzed to establish how the indoor odor acceptability criterion, defined in ASHRAE Standard 62-1981 as an acceptability by 80% of individuals entering the occupied space, depends on other qualities of the indoor air. It was found that the odor intensity alone only partially determined the odor acceptability percentage. The staleness-freshness rating correlated to the odor acceptability better than the odor intensity alone. There was an indication that at low concentrations formaldehyde, or aldehydes, increased odor intensity but also unexpectedly improved the acceptability of odor. This effect merits further study. All these observations point toward the possible importance of odor character, not measured in the ventilation study, in determining the odor acceptability.