Air movement and draught.

One hundred subjects were exposed to air velocities fluctuating in the same manner as in typically ventilated spaces in practice. Each subject participated in three experiments at 20, 23 and 26 degrees C, dressed toobtain a neutral thermal sensation. In each experiment the subject was exposed to six mean velocities from 0.05 to 0.40 m/s. He was asked whether and wherehe could feel air movement and whether it felt uncomfortable. A relation was established between the percentage of people feeling draught and the mean velocity. The subjects were most sensitive to draught on the head region. Lower velocities than those prescribed in present standards are required toreduce complaints of draught in ventilated spaces in practice.