Room air temperature is recommended to be kept 28℃ for conservation of energy today. For human thermal comfort in room temperature of 28℃, it is likely to need personal control of the men dress lighter and, an increased air velocity. The present paper, by questionnaire survey in office at air temperature of 28℃, and experiment with subjects and thermal manikin of various clothes at chamber shows how human may feel to environment with air temperature of 28℃. Additionally, it is proposed to comfortable condition at room temperature of 28℃ in office as clothes, air flow, and radiant temperature.
