The United States Environmental Protection Agency (EPA) has collected extensive indoor air quality data in 100 randomly selected office buildings following a standardized protocol developed for the Building Assessment Survey and Evaluation (BASE) study. These data were collected to provide normative data in typical office buildings for various uses including: a) basis for making policy and guidance development; b) hypothesis development and testing; c) input into risk assessments and environmental models; and, d) comparison of complaint buildings to "typical" building stock.