To understand the effectiveness of some garment adjustment designs for high school uniform in winter, manikin tests and subjective wear trials were carried out. Five series of school uniform ensembles were involved in the experiments. They were further collocated into 17 ensemble configurations with detachable designs (ensembles A and B) and opening structures (ensembles C, D, and E). As manikin test results showed, the thermal insulation of ensembles A, B and C varied most significantly due to their adjustment design. The possible thermal insulation regulation levels were approximately 68% and 80% for ensembles A and B, and 60% and 90% for ensemble C. Two human trials that simulated students’ daily movements between indoor and outdoor classes were conducted with ensemble A. Two climate chambers were used at the same time for indoor and outdoor environment simulation. In Case X, where ensemble A was assumed to be non-detachable, skin temperatures that were 0.6℃ lower were finally observed compared to Case Y, where ensemble A was detachable. Moreover, significantly ( p < 0.1) better thermal comfort and thermal sensation evaluations were given during low-intensity activities in Case Y, especially for the torso segments. The detachable high school uniform design was finally proved to be efficient in improving human thermal comfort under various class environments. It was also concluded that more protective measures should be adopted for the hands and face in the school uniform design process.

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For guiding the setting of working time, it is necessary to develop a realistic clothing model with accurate thermal physical properties including the effects of human body activities and environments in the predicted heat strain model, especially for the high thermal insulation clothing ensembles and high-temperature conditions. In this study, realistic clothing models, including clothing wet thermal insulation ( Icl_w), dynamic thermal insulation ( Icl_vw), and convective heat transfer coefficient considering the temperature difference and walking speed ( hc_vw), were established. Then, we validated the modified predicted heat strain models combined with realistic clothing parameters. The results revealed that the core temperature of the predicted heat strain model combined with Icl_w, Icl_vw, and hc_vw (deviation of 0.1°C) was significantly more accurate than the original predicted heat strain model (variation of 1.5°C) in the environment of 40°C within 65 min of heat exposure. Our study emphasizes the necessity of ensuring the accuracy of clothing thermal physical properties in the predicted heat strain model to improve validity for the specific conditions investigated.

The prediction accuracy of the Predicted Heat Strain (PHS) model is affected by the correction approaches of static thermophysical properties of clothing considering the pumping effects of wind and body movement. In this study, a comparison of different correction algorithms for three types of clothing and their influence on the heat strain predicted by the PHS model was carried out with experimental data obtained from the literature. Results show that the dynamic insulation values calculated by ISO 9920 corrections are larger than those obtained by ISO 7933 when the static insulation values are higher than 0.4 clo, but when the static values are lower than 0.4 clo, it varies contrarily. The dynamic evaporative resistance values calculated with ISO 9920 equations are larger than those with ISO 7933. The prediction accuracy of the PHS model with ISO 9920 corrections and the addition of the walking speed input parameter can be improved for normal clothing (NC) in a hot environment and high clothing insulation. For specialized, insulating, cold weather clothing (SC), ISO 7933 corrections with an added walking speed input parameter to the PHS model have a good prediction precision.

Ambient temperature steps between typical non-work and hot work environments will lead to clothing heat storage and release, which is crucial for human health and thermal comfort. In this study, the influence of five types of ambient temperature steps (from 0ºC/5ºC/10ºC/15ºC/20ºC to 40ºC to 0ºC/5ºC/10ºC/15ºC/20ºC) on the heat storage and release in clothing was investigated using a thermal manikin. A moving and temperature-controlled refrigerated incubator was constructed to realize the temperature step conditions. Results showed that ambient temperature step magnitude was positively related to heat storage and release. Some 80% of the amount of heat storage would be completed in around 10 min after the temperature steps. Increasing the inner clothing layer weight and specific heat capacity for local clothing at the chest, thigh and calf improved their heat storage against the large temperature step conditions. As for the abdomen, its heat storage was the largest. However, the clothing layer configuration impacted its heat release, so it was necessary to guide the heat transfer to the skin. The heat storage in the outer layer was increased by 2% to 39% due to adding the inner layer of the garment. The stored heat discharged completely until the temperature step magnitude exceeded 32.5°C. A multiple linear regression formula was proposed to obtain the clothing average heat storage by considering ambient temperature step magnitude and clothing insulation. The results of this study could contribute to the optimization of thermal protective clothing and improvement of the research on human thermal comfort.