Crawl space concentrations were measured during five sampling events. Adjusted crawl space concentrations were compared to average adjusted indoor concentrations (Table 3). With two exceptions, the fractional differences were negative and within the range of – to – due to lower concentrations in the crawl space relative to indoors. The exceptions were 2-butanone and m/p-xylene with slightly elevated concentrations in the crawl space. Changes in adjusted mean indoor minus outdoor concentrations of 12 of the 22 VOCs over the course of the study are presented in Figures 4 and 5. These plots show that.
