Radiant cooling system for thermal comfort of Thai people was developed. Questionnaires for subjective experiments
were examined for development of radiant cooling system for thermal comfort. Thermal sensation, humid sensation and
air movement sensation were used for thermal comfort assessment. The Predicted Mean Vote (PMV) value was used for
thermal comfort evaluation and it was observed that the PMV values are in the comfortable ranges during 18:00 to
10:00 for air velocity 0.2 m/s and 0.4 m/s. Comfortable periods are extended for higher air velocity. Neutral temperatures
are in the ranges of 26.44˚C - 33.60˚C. The percentage number of dissatisfied (PPD) value for each air velocity
was also investigate and the value of PPD is five for zero value of PMV. Simulation and experimental results were
evaluated by using three indicators, namely, the coefficient of variation (CV), the mean bias error (MBE) and
Chi-Square 2 . The values of CV, MBE and 2 for mean radiant temperature are 14.52%, 1.54% and 3.95˚C, respectively.
Zones of acceptable thermal environment were developed for Thai People. Results revealed that the comfortable
zones of Thai people are in the ranges of relative humidity 50% - 70% and effective temperatures (ET) 24˚C -
27˚C.