Can hypobaric hypoxia affect human thermal comfort? An experimental study in Tibet, China

Abstract

Hypobaric hypoxia is the main environmental feature of the Tibetan plateau which would influence the efficiency of human metabolic heat production and the ability of thermal regulation. In order to understand the influence of the hypoxic environment on the plateau on the thermal comfort of short-term sojourners in Tibet, China, oxygen generators were used to create oxygen-enriched environments, and physiological and psychological reactions of subjects were compared under different oxygen partial pressures (

p_{{\text{O}}_2}

\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${p_{{{\rm{O}}_2}}}$$\end{document}

) and air temperatures (t_a). The results showed that subjects’ thermal sensation, thermal comfort and mean skin temperature decreased with a decrease in the oxygen partial pressure. When t_a=17 °C, the influence of oxygen partial pressure was more pronounced, compared to

p_{{\text{O}}_2}=16.4\text{kPa}

\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${p_{{{\rm{O}}_2}}} = 16.4\,\,{\rm{kPa}}$$\end{document}

, the thermal sensation of subjects under

p_{{\text{O}}_2}=13.7\text{kPa}

\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$${p_{{{\rm{O}}_2}}} = 13.7\,\,{\rm{kPa}}$$\end{document}

decreased by 33%. The rate of subjects feeling comfortable decreased by 25%, and the mean skin temperature decreased by 0.7 °C. The hypoxic environment of the plateau exacerbates human discomfort. Therefore, it is necessary to fully understand the actual thermal requirements of sojourners in Tibet, China. The results of this study would have implications for a better understanding of thermal comfort characteristics in the hypoxia environment in plateau.

Keywords

thermal comfort / hypoxia / high altitude / oxygen enrichment / physiological responses / short-term sojourner

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