The Building Assessment Survey and Evaluation Study (BASE) is a cross-sectional study of randomly selected public and commercial office buildings from across the U.S.  The BASE study used a standardized protocol to collect extensive indoor air quality data from one hundred randomly selected public and commercial office buildings in ten climatic regions in thirty-seven cities in twenty-five States.

EPA conducted the BASE Study, because baseline information from typical buildings was sparse, no reference existed with which to compare the so-called "sick" buildings. The data collected provides normative IAQ data and baseline symptom rates in typical office buildings.

The raw data from this study is available to researchers and others interested in IAQ and office buildings.

For more detailed information on the BASE study and how to get the raw data see www.epa.gov/indoor-air-quality-iaq/building-assessment-survey-and-evaluation-study.