Abstract
In winter season, the survey was performed in three commercial office buildings in the metropolitan Seoul, Pusan, and Gwangju city. The purpose of the survey was to evaluate the effectiveness of ventilation for offices in commercial buildings. The data were compared to standard of applicable to the indoor ventilation in office. The results indicated that the most commercial office buildings used the air handing unit and fan coil unit as HVAC system, and the intake amount of fresh outdoor air were very inadequate to compared to the ASHRAE standard value of $0.57\;m^3/min/person$. Also the surveyed all commercial office building used the HVAC system as a meas of controlling temperature for office indoor air. Ultimately, these results presented that there were possibility of evoking indoor air quality problems by the insufficient ventilation.