Ergonomics in built environments: Prospects of human thermal comfort research

Abstract

<p indent="0mm">Heating, ventilation, and air conditioning (HVAC) systems, which have been around since the early 20th century, were originally designed to support fine industrial processes and thus pursue the goal of uniform, steady-state environmental control. And the HVAC systems for civil buildings which were widely used later followed such an idea to create uniform and steady-state thermal environments. For decades, a large number of domestic and foreign research results have shown that the uniform and steady thermal environment is not necessarily the most beneficial to people’s comfort and health, but it needs more energy consumption. As one of the earliest scientific theories formed in the field of ergonomics in built environments, the theory of human thermal comfort has effectively guided the development of the building thermal environment control methods, technologies, and products globally during the process of industrialization. In the new era of global warming and low-carbon buildings, the theoretical science of human thermal comfort undertakes the new mission of promoting the discipline of building technology and achieving the goals to develop “low-carbon” and “healthy” buildings. The future development of human thermal comfort research will have two important directions. One is the in-depth scientific understanding of the complex relationship between human and the multi-factor thermal environment, not only for human comfort needs, but also paying more attention to the impact on health. The other is the technological innovation that these new scientific understandings may bring, which can not only enhance personalized thermal comfort of people, but also effectively reduce the energy demand of thermal environment control in buildings. The first development direction above requires the combination of traditional engineering with medicine and public health, that is, the intersection of medicine and industry. The second development direction requires interdisciplinary cooperation between the discipline of built environment and other engineering disciplines such as materials, information, and energy. Based on the review of the development process of human thermal comfort as well as the research practice of our team, we have formed the following prospects centering on the above two future directions. (1) Compared with steady-state thermal environments, the dynamic thermal environment is more in line with people’s thermal comfort needs. The natural outdoor environment is a typical dynamic thermal environment, which is often more pleasant than steady neutral indoor environments. Attention should be paid to the use of suitable outdoor natural conditions, or the technologies to imitate natural conditions when creating indoor environments, so as to enhance people’s pleasure. (2) By providing local heating or local cooling, the human body can achieve thermal comfort in a cold or hot environment, so that the indoor comfortable temperature range can be greatly expanded. Therefore, future HVAC systems should focus on providing individual scale “precise thermal service” for indoor personnel, and develop personalized and wearable individual thermal comfort equipment, which can not only meet the different thermal comfort needs of people, but also help to save building energy. (3) Staying in a neutral thermal environment for a long time could weaken the heat stress ability of the human body, while moderate cold or hot exposure is beneficial to maintain human health. In the future, the indoor thermal environment system should be able to connect sensors to monitor the key thermal physiological indicators of the human body, and then support users to carry out cold or hot exposure exercise in accordance with health needs by adjusting the indoor thermal environment, so as to enhance their heat stress ability and keep healthy.