Other Studies of VOC Concentrations in U.S. Office Buildings
Two other studies of VOC concentrations of multiple U.S. office buildings were conducted in the 1990's and reported in the literature. In 1991, Shields et al. (1996) measured indoor and outdoor VOC concentrations in 11 telephone company administrative offices as part of a larger study of telephone company buildings. The admin buildings were located throughout the U.S. VOCs were collected with a passive sampler (OVM 3500, 3M). These were deployed over a 6-week period. The samplers were extracted with a solvent. The extracts were analyzed for more than 30 individual VOCs by GC/MS. Table 3 of the article presents the GM concentrations (in µg/m³), the geometric standard deviations and frequencies of detection for the most prevalent VOCs. The compounds that were found primarily indoors in the admin buildings included 2-butoxyethanol, alpha-pinene, limonene, branched C10 and C11 alkane hydrocarbons, dichlorobenzenes, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and trimethylpentanediol mono- and diisobutyrates.

Between the summer of 1995 and the winter of 1997-98, the U.S. Environmental Protection Agency measured indoor and outdoor VOC concentrations at 100 office buildings throughout the U.S as part of their Building Assessment and Evaluation study (BASE) (http://www.epa.gov/iaq/largebldgs/). The buildings were randomly selected without regard to indoor air quality concerns. For each building, VOC samples were collected on multisorbent samplers over a workday at three indoor locations and one outdoor location. VOC samples were also collected with canisters. The samples were analyzed by GC/MS. Aldehyde samples collected on treated cartridges were solvent eluted and analyzed by HPLC. A portion of the data has been released publicly (Girman et al, 1999). The range of quantifiable indoor concentrations for 48 individual VOCs in 56 buildings organized by frequency of occurrence was presented. In addition, frequency distributions were shown for the 12 VOCs with the highest median indoor concentrations (in µg/m³). In order of decreasing median concentration, these compounds are acetone, toluene, limonene, xylene isomers, 2-butoxyethanol, n-undecane, benzene, 1,1,1-trichloroethane, n-dodecane, hexanal, nonanal and n-hexane.