Field evaluation of the indoor environment of naturally ventilated offices.

Experiments were carried out in four naturally ventilated offices to measure the indoor environmental parameters such as air velocity, turbulence intensity and air temperature at three vertical levels, Air change rates for various indoor and outdoor climates were detetmined. The concentration of carbon dioxide in the room was monitored. Subjective assessment was made to evaluate the thermal comfort and indoor air quality in the offices. The effect of opening windows and doors on the indoor comfort conditions was also investigated. Models were developed for assessing the indoor environment based on the field measurements. It was found that in real situations the occupants were more sensitive to the deviation of air temperature from neutrality than predicted using Fanger's comfort model. The indoor environment in the offices was found to be unsatisfactory and recommendations are given for its improvement.