Information on state-of-the-art techniques for measuring air change rates. Many papers contain measured data on either airtightness or air change rates, some from large datasets. Papers also address the error associated with making field measurement using various techniques. 22 peer-reviewed papers appear in sections on tracer gas techniques, air exchange rate measurement, residential airtightness, multizone leakage, and comparison of techniques. For blower door contractors, researchers, specification writers, government agencies.