The average thermal sensation of occupants in the hot and humid region of Asia is different from that of Europeans and Americans. Office occupants in buildings equipped with air conditioners tend to find the thermal environment uncomfortable due to individual differences of thermal sensation. In this research, the thermal environment was measured in two office buildings in Taipei during summer. The Occupants' sensation of the thermal environment was recorded using a voting machine developed by team researchers. Thirty-six occupants were requested to report the feeling of an unacceptable thermal environment by pressing a red or blue button on the voting machine when feeling hot or cold, respectively. The results show that operative temperature and absolute humidity varied at the times an individual was out of the comfort zone based on ASHRAE Standard 55(2013). Although all individuals were in the same environment, some occupants reported feeling unacceptably, even though they were at a temperature and humidity level considered to be within the comfort zone. About 60% of unacceptable votes reported feeling cold while within the comfort zone. This research suggests that it is possible to revise existing comfort criteria in offices in Taiwan or other hot or humid regions in Asia.