Author: Zhao, Yijie
Title: The role of personal cooling system (PCS) in combating body heat strain : a case study in Hong Kong
Advisors: Chan, P. C. Albert (BRE)
Yi, Wen (BRE)
Degree: Ph.D.
Year: 2018
Subject: Hong Kong Polytechnic University -- Dissertations
Construction industry -- Health aspects -- China -- Hong Kong
Heatstroke -- Prevention
Industrial hygiene
Department: Department of Building and Real Estate
Pages: xvii, 243 pages : color illustrations
Language: English
Abstract: The construction industry features high-level risks on the safety and health of the working population. The safety and health of construction workers should be given with significant attention by the research community and governments. The nature of climatic and urbanised conditions in Hong Kong poses considerable threats to occupational safety and health. Heat stress is a major occupational hazard in Hong Kong's construction industry. During the hot and humid summer season in Hong Kong, construction workers are susceptible to heat stress due to physically strenuous and demanding work activities, high air temperature and relative humidity, and prolonged exposure to sunlight. Various cooling countermeasures [e.g. personal cooling system (PCS), fanning and hand and/or forearm immersion in cold water] have been proposed to relieve heat stress and improve work performance. PCS, in the form of cooling garment, enables microclimate cooling around the body, thereby promoting heat dissipation. PCS is amongst the most effective cooling methods. Various PCSs have been used in firefighting, hazmat operations, military and sports. However, their application in the construction industry is still in its infancy, and their effects are yet to be evaluated. To bridge this research gap and develop practical solutions, a study was undertaken to engineer and design a tailor-made PCS for construction workers. This PCS is a two-layer cooling vest, specifically designed to wear over the construction uniform. The PCS design comprehensively considers cooling effect, cooling duration, weight, mobility, comfort, aesthetics, visibility and safety of construction workers. This initiative requires further evaluation on the effectiveness and practicality of this newly designed PCS to protect construction workers from heat-related injuries. The current study aims to develop a cooling intervention with this newly designed PCS to reduce body heat strain in the construction industry. The main objectives are to present a research framework for cooling intervention development research, examine the effectiveness and applicability of wearing the PCS on alleviating heat strain and formulate recommendations on precautionary measures to safeguard workers' health and safety whilst working in a hot environment. Experimentation, which is a scientific approach that facilitates the discovery and creation of knowledge, is adopted in this study. A series of laboratory tests on thermal manikin and human subjects and field wear trial studies are conducted in sequence to assess the cooling capability, effectiveness and applicability of the newly designed PCS.
Results of the thermal manikin test in the laboratory revealed that the newly designed PCS displays higher cooling power and longer cooling duration than a commercially available cooling vest. An optimal cooling intervention, in which the PCS is used during rest between repeated bouts of work, is determined through human wear trials in the climatic chamber. The findings of the wear trial test in the climatic chamber indicated that the newly designed PCS can significantly attenuate physiological and perceptual strains and improve work performance compared with the control condition (no cooling intervention). The field experiments showed that the heat strain of the steel bar workers wearing the PCS during rest is significantly reduced compared with that of the control condition. Furthermore, field surveys from 143 construction workers across two trades on construction sites revealed that approximately 91% of the workers are satisfied with the newly designed PCS. Most of these workers also provide good subjective evaluation on this PCS. The current study develops an optimal cooling intervention and presents a fresh perspective to further improve occupational safety and health in construction. This study helps address the research gap caused by the lack of cooling intervention research in construction. The experimentation used in this study is well structured, rigorous and reliable. Moreover, this study is carried out within a multidisciplinary context (e.g. construction management, industrial hygiene, occupational hygiene, textile science, biological science and exercise science) to deal with scientific, theoretical, technical, statistical, sociopolitical and practical issues, thereby promoting the collaboration between academia and industry practitioners.
Rights: All rights reserved
Access: open access

Files in This Item:
File Description SizeFormat 
991022165759603411.pdfFor All Users5.89 MBAdobe PDFView/Open


Copyright Undertaking

As a bona fide Library user, I declare that:

  1. I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
  2. I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
  3. I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.

By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.

Show full item record

Please use this identifier to cite or link to this item: https://theses.lib.polyu.edu.hk/handle/200/9659