Field testing of natural ventilation of residential buildings in Beijing in summer

sing the CO₂ tracer gas concentration decay method, taking eight residences in Beijing region as research subjects, measures and obtains air changes through exterior windows in the bedroom at night under different open-closed conditions of door and windows. The results indicate that the air infiltration through the gaps of windows and doors can not satisfy the requirement of indoor air quality when the windows and doors closed. Analyses the relationship between the single-side ventilation rate and temperature difference of indoor and outdoor, outdoor wind speed and direction, and compares the measured ventilation rate with the results from the empirical formulas presented by Warren. The results show that when the windows opened are in the crosswind side or leeward side, the calculated values are basically lager than the measured values, and the empirical formulas should be modified.