Effects of temperature steps on human health and thermal comfort

摘要

Human beings are often likely to expose themselves to sudden temperature change in daily life. For example, when entering/exiting an air-conditioned building from/to outdoors people may suffer not only thermal discomfort but also even some potential health problems. In this study, the influence of different air temperature step-changes (S5:32 degrees C-370 degrees C-32 degrees C, 511:26 degrees C-37 degrees C-26 degrees C, and 515:22 degrees C-37 degrees C-22 degrees C) on human health and thermal comfort was studied with 24 volunteered participants in the laboratory experiment. Results show that perspiration, eyestrain, dizziness, accelerated respiration and heart rate are sensitive self-reported symptoms in response to temperature step-changes. Thermal sensation, comfort and acceptability just before temperature step are significantly distinguished from that immediately after step change except for thermal comfort and acceptability in up-step of S15 (22 degrees C-37 degrees C). Hysteresis phenomenon appears when subjects move from neutral to warm environment. Psychological lead occurs after both up-steps and down-steps. Temperature step magnitude and changing direction have significant impact on human response to temperature steps. (C) 2015 Elsevier Ltd. All rights reserved.