Awareness, adoption readiness and challenges of railway 4.0 technologies in a developing economy.

The railway industry has witnessed increasing adoption of digital technologies, known as Railway 4.0, that is revolutionizing operations, infrastructure, and transportation systems. However, developing countries face challenges in keeping pace with these technological advancements. With limited research on Railway 4.0 adoption in developing countries, this study was motivated to investigate the awareness, readiness, and challenges faced by railway professionals towards implementing Railway 4.0 technologies. The aim was to assess the level of awareness and preparedness and identify the key challenges influencing Railway 4.0 adoption in Nigeria's railway construction industry. A questionnaire survey (was distributed to professionals in the railway construction sector to gather their perspectives on awareness of, preparation for, and challenges associated with the use of Railway 4.0 technologies. The results revealed that awareness of Railway 4.0 technologies was moderate, while readiness was low among the professionals. Using exploratory factor analysis, 10 underlying challenge constructs were identified including lack of technical know-how, resistance to change, infrastructure limitations, and uncertainty about benefits, amongst others. Partial Least Square Structural Equation Modelling (PLS-SEM) confirmed these constructs, with reliability and availability, lack of technical know-how, lack of training and resources, and uncertainties in benefit and gains having significant influence on awareness and readiness. The study concludes that focused efforts in training, infrastructure improvement, supportive policies, and communicating the advantages of Railway 4.0 are critical to drive adoption in Nigeria and other developing economies. The findings provide insights into tailoring Railway 4.0 implementation strategies for developing contexts.

Improving Safety Performance of Construction Workers through Learning from Incidents.

Learning from incidents (LFI) is a process to seek, analyse, and disseminate the severity and causes of incidents, and take corrective measures to prevent the recurrence of similar events. However, the effects of LFI on the learner's safety performance remain unexplored. This study aimed to identify the effects of the major LFI factors on the safety performance of workers. A questionnaire survey was administered among 210 construction workers in China. A factor analysis was conducted to reveal the underlying LFI factors. A stepwise multiple linear regression was performed to analyse the relationship between the underlying LFI factors and safety performance. A Bayesian Network (BN) was further modelled to identify the probabilistic relational network between the underlying LFI factors and safety performance. The results of BN modelling showed that all the underlying factors were important to improve the safety performance of construction workers. Additionally, sensitivity analysis revealed that the two underlying factors-information sharing and utilization and management commitment-had the largest effects on improving workers' safety performance. The proposed BN also helped find out the most efficient strategy to improve workers' safety performance. This research may serve as a useful guide for better implementation of LFI practices in the construction sector.

Opportunities and Challenges for Construction Health and Safety Technologies under the COVID-19 Pandemic in Chinese Construction Projects.

The Coronavirus disease 2019 (COVID-19) pandemic has resulted in significant delays and cost overrun in construction projects. The implementation of health and safety (H&S) technologies is one of the most important strategies to alleviate the adverse impacts of COVID-19 on the construction industry and help the industry adapt to the new normal. This study aims to evaluate the adoption of H&S technologies for pandemic management in the construction sector under the COVID-19 pandemic. Semi-structured interviews with eighteen practitioners engaged from construction companies and technology firms were conducted to collect their views on the driving forces and issues of the adoption of H&S technologies for pandemic management in Chinese construction projects. The results reveal that the major H&S technologies used included the health quick response (QR) code system, artificial intelligence (AI)-powered fever monitoring, and site access control system. These technologies were reported to be effective in preventing the spread of the pandemic in workplaces. The findings of the study amplify that the pandemic may serve as an acceleration of the adoption of H&S technologies in the construction sector. Other technologies, such as building information modeling, drones, AI-based safety monitoring, and robotics, however, were seldom used in the studied projects. The interviewees addressed several problems regarding the implementation of these technologies. High costs of technologies, a lack of client support, and disruptions to the normal work process were the main hurdles of the adoption of these technologies. The results indicated that the external influence factor-the COVID-19 pandemic-could considerably drive the use of H&S technologies, whereas the internal influence factors-cost and compatibility of technology-might be the major barriers to technology adoption. To encourage the wider use of H&S technologies in construction, the government is recommended to support the technology transformation by granting financial subsidies for costs involved in innovation adoption. Project owners may consider investing substantially in H&S technologies that can strengthen their resilient and innovative ability to adapt to the post-COVID-19 landscape. The present results will be useful to industry stakeholders and researchers interested in developing H&S technologies for combating the COVID-19 pandemic and future crises.

Exploring the Barriers to and Motivators for Using Digital Mental Health Interventions Among Construction Personnel in Nigeria: Qualitative Study.

BACKGROUND: Work-related stress in the construction industry increases the prevalence of depression and anxiety among personnel. In low-resource settings such as Nigeria, construction personnel face high demands and severe working conditions but only have a few services to address their mental health needs. With emerging research showing that digital interventions can be used to self-manage mental health across diverse settings, there may be new opportunities to support construction personnel in the construction industry. OBJECTIVE: This study aims to determine the use of digital interventions for mental health management among construction personnel in Nigeria and to explore the factors that facilitate or impede the use of these interventions. METHODS: This qualitative study explored the perspectives of a convenience sample of 62 construction personnel. The data were subjected to inductive content analysis. RESULTS: A total of 6 barrier and 3 motivator themes were identified and categorized into 2 groups. The barrier themes were subcategorized into barriers to adoption and barriers to persistent use, whereas the motivator themes were subcategorized into intrinsic and extrinsic motivators. Lack of awareness and knowledge about the interventions may constitute a barrier to adoption and use. Participants frequently reported concerns regarding their effectiveness and usability. CONCLUSIONS: This study provides an understanding of the design needs required to facilitate sustained self-management of mental health based on the experiences and expectations of construction personnel with digital interventions.

Experimental Study on the Efficacy of a Novel Personal Cooling Vest Incorporated with Phase Change Materials and Fans.

In recent years, personal cooling has aroused much attention because it can achieve both localized high-level thermal comfort and build energy savings. In this study, a novel hybrid personal cooling vest (PCV) incorporated with phase change materials (PCMs) and ventilation fans was developed, and its efficacy was investigated by human trials in a hot-humid climate chamber. Three generally accepted indices (thermal load, Q; thermal sensation, TS; and physiological strain index, PSI) and a new proposed index (cumulative heat storage, CHS) during human trials were comparatively studied between the two human trial groups, i.e., the PCV group (wearing the PCV) and the CON group (without PCV). Results found that TS, PSI, and CHS were significantly reduced by the PCV, which suggests that the PCV can significantly improve both the perceptual and physiological strain. In addition, a strong linear relationship (r2 = 0.8407) was found between the proposed index of CHS with PSI, which indicates the applicability and reliability of CHS for assessing physiological heat strain.

Mental Ill-Health Risk Factors in the Construction Industry: Systematic Review.

Mental ill health is a significant cause of suicide and disability worldwide. It has particularly affected the construction industry. The construction labor sectors in Australia and the United Kingdom have suicide rates 2 and 3.7 times higher, respectively, than their overall national averages, which has attracted the attention of researchers and the industry. However, few studies have examined the state of construction workers' mental health. This paper systematically reviews the existing body of knowledge on mental health in the construction industry. In total, 16 journal articles met inclusion criteria, and 32 risk factors (RFs) were deduced. The foremost RFs were related to job demand and job control. A conceptual framework and checklist to aid in better understanding these RFs were developed. In assessing mental health, the primary tool used was the Depression Anxiety Stress Scale. The findings of this study help to deepen the understanding of professional mental health assessment scales and relevant RFs and protective factors as used in the construction industry. The study concludes that stronger methodologies are needed for studies into RFs and protective factors in the construction industry.

An Empirical Study on Construction Process Corruption Susceptibility: A Vignette of International Expertise.

Construction process stages are argued to be vulnerable to the prevalence of corrupt practices. However, the validity of this argument has not been empirically explored in the extant literature of construction management. Therefore, this study examines the stages of the construction process susceptibility to corruption and its most prominent forms of corrupt activities (within the respective stages). A total of forty-four project-related professionals were involved in an expert survey to assess such susceptibilities and the criticality of the identified corrupt activities at each stage. A comparative study of expert views from developing regions against experts from developed regions is conducted. Expert scoring results revealed that three stages are most susceptible, namely: project execution, pre-qualification and tender stages. Such results were confirmed by application of the Mann-Whitney U test statistics tool, showing wide disparities in seven out of eleven identical stages. This study is intended to incite polemic discussions and greater empirical, evidence-based research from scholars in both developed and developing countries. This study adds to the extant literature corruption-related works on the construction process through deeper understanding of the dynamic nature of corrupt practices involved in the stages of the construction process in developing countries. Practically, it intends to offer a veritable plethora of information on the critical stages of the construction process for industry practitioners, policymakers and anti-corruption bodies to careen their attention towards the fight against corruption.

Distinguishing Characteristics of Corruption Risks in Iranian Construction Projects: A Weighted Correlation Network Analysis.

The construction industry consistently ranks amongst the highest contributors to global gross domestic product, as well as, amongst the most corrupt. Corruption therefore inflicts significant risk on construction activities, and overall economic development. These facts are widely known, but the various sources and nature of corruption risks endemic to the Iranian construction industry, along with the degree to which such risks manifest, and the strength of their impact, remain undescribed. To address the gap, a mixed methods approach is used; with a questionnaire, 103 responses were received, and these were followed up with semi-structured interviews. Results were processed using social network analysis. Four major corruption risks were identified: (1) procedural violations in awarding contracts, (2) misuse of contractual arrangements, (3) neglect of project management principles, and, (4) irrational decision making. While corruption risks in Iran align with those found in other countries, with funds being misappropriated for financial gain, Iran also shows a strong inclination to champion projects that serve the government's political agenda. Root cause identification of corruption risks, namely, the noticeable impact of authoritarianism on project selection in Iran, over criterion of economic benefit or social good, is a significant outcome of this study.

Building Healthy Eating Knowledge and Behavior: An Evaluation of Nutrition Education in a Skill Training Course for Construction Apprentices.

BACKGROUND: Prior research has found poor health among construction workers is related to poor nutrition and low fruit and vegetable consumption. Promoting nutrition knowledge can improve dietary behaviors, but nutrition education among construction workers is limited. We evaluated the effectiveness of nutrition education on fruit and vegetable consumption among construction apprentices. In this pilot evaluative study, 36 construction apprentices enrolled in skill training programs received two 1.5-hour nutrition classes. Twelve questions addressing healthy eating knowledge and behavior were administered at baseline, after intervention, and at three months follow-up. After intervention, daily fruit consumption improved from baseline (mean (s.d.) =1.42 (0.55)) to post intervention (mean (s.d.) =1.72 (0.70)) (p < 0.05) and to three months follow-up (mean(s.d.) =1.94 (0.83)) (p > 0.05). After intervention, daily vegetable consumption improved from baseline (mean (s.d.) =1.67 (0.59)) to post intervention (mean (s.d.) =1.97 (0.74)) (p < 0.05) and to three months follow-up (mean (s.d.) = 2.19 (0.82)) (p > 0.05). Younger construction apprentices showed better healthy eating knowledge at post intervention and three months follow-up (p > 0.05). Working in normal hours showed better healthy eating knowledge at post intervention but not at three months follow up (p > 0.05). Both age groups and working hours did not show significant differences on healthy eating behaviour. Nutrition education implemented as a three-hour session within skill courses may possibly promote fruit and vegetable consumption among construction apprentices. Further research with control group is required to support the findings in this study.

A Survey of Work-Related Pain Prevalence Among Construction Workers in Hong Kong: A Case-Control Study.

Construction workers undertake demanding physical work and face high risk of injuries in poor working environments. This case-control study investigated the extent of their musculoskeletal pain incidence at work. A total of 2021 construction workers in different trades were interviewed on-site in a survey from December 2017 to December 2018. The survey results revealed that the pain prevalence of the subjects in the last 24 h was 10.6 %. The worst and top most common pain spots caused by work were central lower back, left/right shoulders, and knees. Regarding pain management, their most common method was to ignore the pain (21.4%). The average percentage of pain relief after receiving treatment in the 24 h was 37.12%. Besides, significant differences were found between the pain and non-pain groups regarding their employment duration in current job or their average sleep duration in the 24 h. The study showed that those with multiple and bilateral pain sites had pain interference on their living activities.

Reduction of Physiological Strain Under a Hot and Humid Environment by a Hybrid Cooling Vest.

Chan, APC, Yang, Y, Wong, FKW, Yam, MCH, Wong, DP, and Song, W-F. Reduction of physiological strain under a hot and humid environment by a hybrid cooling vest. J Strength Cond Res 33(5): 1429-1436, 2019-Cooling treatment is regarded as one of good practices to provide safe training conditions to athletic trainers in the hot environment. The present study aimed to investigate whether wearing a commercial lightweight and portable hybrid cooling vest that combines air ventilation fans with frozen gel packs was an effective means to reduce participants' body heat strain. In this within-subject repeated measures study, 10 male volunteers participated in 2 heat-stress trials (one with the cooling vest-COOL condition, and another without-CON condition, in a randomized order) inside a climatic chamber with a controlled ambient temperature 33° C and relative humidity (RH) 75% on an experimental day. Each trial included a progressively incremental running test, followed by a 40-minute postexercise recovery. Core temperature (Tc), heart rate (HR), sweat rate (SR), rating of perceived exertion (RPE), exercise duration, running distance, and power output were measured. When comparing the 2 conditions, a nonstatistically significant moderate cooling effect in rate of increase in Tc (0.03 ± 0.02° C·min for COOL vs. 0.04 ± 0.02° C·min for CON, p = 0.054, d = 0.57), HR (3 ± 1 b·min·min for COOL vs. 4 ± 1 b·min·min for CON, p = 0.229, d = 0.40), and physiological strain index (PSI) (0.20 ± 0.06 unit·min for COOL vs. 0.23 ± 0.06 unit·min for CON, p = 0.072, d = 0.50) was found in the COOL condition during exercise. A nonstatistically significant (p > 0.05) trivial cooling effect (d < 0.2) was observed between the COOL and CON conditions for measures of exercise duration, running distance, power output, SR, and RPE. It is concluded that the use of the hybrid cooling vest achieved a moderate cooling effect in lowering the rate of increase in physiological strain without impeding the performance of progressively incremental exercise in the heat.

Causal Factors of Corruption in Construction Project Management: An Overview.

The development of efficient and strategic anti-corruption measures can be better achieved if a deeper understanding and identification of the causes of corruption are established. Over the past years, many studies have been devoted to the research of corruption in construction management (CM). This has resulted in a significant increase in the body of knowledge on the subject matter, including the causative factors triggering these corrupt practices. However, an apropos systematic assessment of both past and current studies on the subject matter which is needful for the future endeavor is lacking. Moreover, there is an absence of unified view of the causative factors of corruption identified in construction project management (CPM). This paper, therefore, presents a comprehensive review of the causes of corruption from selected articles in recognized construction management journals to address the mentioned gaps. A total number of 44 causes of corruption were identified from 37 publications and analyzed in terms of existing causal factors of corruption, annual trend of publications and the thematic categorization of the identified variables. The most identifiable causes were over close relationships, poor professional ethical standards, negative industrial and working conditions, negative role models and inadequate sanctions. A conceptual framework of causes of corruption was established, after categorizing the 44 variables into five unique categories. In descending order, the five constructs are Psychosocial-Specific Causes, Organizational-Specific Causes, Regulatory-Specific Causes, Project-Specific Causes and Statutory-Specific Causes. This study extends the current literature of corruption research in construction management and contributes to a deepened understanding of the causal instigators of corruption identified in CPM. The findings from this study provide valuable information and extended knowledge to industry practitioners and policymakers as well as anti-corruption agencies in the formulation and direction of anti-corruption measures. To corruption researchers in CM, this study is vital for further research.

A Bayesian Network Model for Reducing Accident Rates of Electrical and Mechanical (E&M) Work.

Accidents in Repair, Maintenance, Alteration, and Addition (RMAA) work have become a growing concern, in recent years. The repair and maintenance works of electrical and mechanical (E&M) installations involves a variety of trades, a large number of practitioners and a series of high-risk activities. The uniqueness of E&M work, in the RMAA sector, requires a discrete and specific research to improve its safety performance. Understanding the causal relationships between safety factors and the number of accidents becomes crucial to develop a more effective safety management strategy. The Bayesian Network (BN) model is proposed to establish a probabilistic relational network between the causal factors, including both safety climate factors and personal experience factors that have influences on the number of accidents related to E&M RMAA work. The data were collected using a survey questionnaire, involving a hundred and fifty-five E&M practitioners. The BN results demonstrated that safety attitude and safety procedures were the most important factors to reduce the number of accidents. The proposed BN provides the ability to find out the most effective strategy with the best utilization of resources, to reduce the chance of a high number of E&M accidents, by controlling a single factor or simultaneously controlling, both, the safety climate and personal factors, to improve safety performance.

Impacts of cooling intervention on the heat strain attenuation of construction workers.

This study aimed to evaluate the effectiveness and practicality of a cooling intervention with a newly designed cooling vest on heat strain attenuation in the construction industry. Fourteen construction workers volunteered to participate in the field study. Each participant took part in two trials, i.e., cooling and control. Construction work included morning and afternoon sessions. Cooling intervention was implemented for 15 and 30 min during the morning and afternoon rest periods, respectively, between repeated bouts of work. Micrometeorological (wet-bulb globe temperature [WBGT]), physiological (tympanic temperature and heart rate), and perceptual (ratings of perceived exertion [RPE] and thermal sensation) measurements were taken during the test. Heat strain indices, including physiological strain index (PSIHR) and perceptual strain index (PeSI), were estimated accordingly. During the study, construction workers were exposed to a hot environment with a mean WBGT of 31.56 ± 1.87 °C. Compared with the control, physiological and perceptual strain were significantly reduced in the cooling condition during rest and subsequent work periods (p < 0.05; d = 0.24-1.07, small to large cooling effect). Cooling intervention significantly alleviates heat strain in the construction industry. The effectiveness and practicality of a proposed cooling intervention were tested in a field study. Results provide a reference for setting guidelines and promoting application on a range of construction sites.

Accidents of Electrical and Mechanical Works for Public Sector Projects in Hong Kong.

A study on electrical and mechanical (E&M) works-related accidents for public sector projects provided the opportunity to gain a better understanding of the causes of accidents by analyzing the circumstances of all E&M works accidents. The research aims to examine accidents of E&M works which happened in public sector projects. A total of 421 E&M works-related accidents in the "Public Works Programme Construction Site Safety and Environmental Statistics" (PCSES) system were extracted for analysis. Two-step cluster analysis was conducted to classify the E&M accidents into different groups. The results identified three E&M accidents groups: (1) electricians with over 15 years of experience were prone to 'fall of person from height'; (2) electricians with zero to five years of experience were prone to 'slip, trip or fall on same level'; (3) air-conditioning workers with zero to five years of experience were prone to multiple types of accidents. Practical measures were recommended for each specific cluster group to avoid recurrence of similar accidents. The accident analysis would be vital for industry practitioners to enhance the safety performance of public sector projects. This study contributes to filling the knowledge gap of how and why E&M accidents occur and promulgating preventive measures for E&M accidents which have been under researched.

Relationships among Safety Climate, Safety Behavior, and Safety Outcomes for Ethnic Minority Construction Workers.

In many countries, it is common practice to attract and employ ethnic minority (EM) or migrant workers in the construction industry. This primarily occurs in order to alleviate the labor shortage caused by an aging workforce with a lack of new entrants. Statistics show that EM construction workers are more likely to have occupational fatal and nonfatal injuries than their local counterparts; however, the mechanism underlying accidents and injuries in this vulnerable population has been rarely examined. This study aims to investigate relationships among safety climate, safety behavior, and safety outcomes for EM construction workers. To this end, a theoretical research model was developed based on a comprehensive review of the current literature. In total, 289 valid questionnaires were collected face-to-face from 223 Nepalese construction workers and 56 Pakistani construction workers working on 15 construction sites in Hong Kong. Structural equation modelling was employed to validate the constructs and test the hypothesized model. Results show that there were significant positive relationships between safety climate and safety behaviors, and significant negative relationships between safety behaviors and safety outcomes for EM construction workers. This research contributes to the literature regarding EM workers by providing empirical evidence of the mechanisms by which safety climate affects safety behaviors and outcomes. It also provides insights in order to help the key stakeholders formulate safety strategies for EM workers in many areas where numerous EM workers are employed, such as in the U.S., the UK, Australia, Singapore, Malaysia, and the Middle East.

Investigating ethnic minorities' perceptions of safety climate in the construction industry.

INTRODUCTION: An increasing number of ethnic minorities (EMs) have been employed in the construction industry to alleviate severe labor shortages in many countries. Unfortunately, statistics show that EMs have higher fatal and non-fatal occupational injury rates than their local counterparts. However, EMs are often underrepresented in safety climate (SC) research as they are difficult to reach and gauge their perception. A positive relationship has been widely found between SC and safety performance. Understanding the safety perceptions of EMs helps to reduce injuries and improve their safety performance. METHOD: Based on a sample of 320 EMs from 20 companies in the construction industry, exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to identify the SC factors of EMs, and validate the extracted factors, respectively. Multivariate analysis of variance was undertaken to examine mean differences in perceptions of SC by personal characteristics. RESULTS: Three SC factors for EMs encapsulating 16 variables were identified through EFA. The hypothesized CFA model for a three-factor structure derived from EFA showed a satisfactory goodness-of-fit, composite reliability, and construct validity. CONCLUSIONS: Three SC factors were identified, namely: (a) safety management commitment, safety resources, and safety communication; (b) employee's involvement and workmate's influence; and (c) perception of safety rules, procedures and risks. The perceptions of SC differed significantly by nationality, marital status, the number of family members supported, and drinking habit. PRACTICAL APPLICATIONS: This study reveals the perception of EMs toward SC. The findings highlight the areas for safety improvement and provide leading indicators for safety performance of EMs. The findings are also enlightening for countries with a number of EMs, such as the United Sates, the United Kingdom, Australia, Singapore, and the Middle East.

A field study of the effectiveness and practicality of a novel hybrid personal cooling vest worn during rest in Hong Kong construction industry.

A novel hybrid cooling vest (HCV) incorporated with phase change materials (PCMs) and ventilation fans has been developed for construction workers in Hong Kong to attenuate heat stress and prevent heat-related illnesses, and its effectiveness and practicality have been validated in this study. A total of 140 wear trials involving of 140 workers were conducted in Hong Kong construction sites during the summer time. Each wear trial involves a two-day wear test, of which one day workers wore the HCV (denoted as VEST) during resting, and another day they wore traditional workwear (denoted as CON). Subjects were asked to rate their perceived exertion (RPE), thermal sensations (TS) and 7 other subjective attributes. There were significant differences in the effectiveness on reducing workers' heat strain between VEST and CON in terms of alleviations of heart rate (ΔHR), ΔTS, ΔRPE as well as ΔPeSI (p < 0.001). The practicality of HCV is evidenced by a significant improvement by 0.93-1.34 on the rating scores of perceived cooling effect, sensations of comfort and skin dryness during rest and fatigue recovery in VEST at the level of 0.05, and high ratings of 4.85-5 (rating scale from 1 to 7, and the higher the better) by subjects on the preference, fitness as well as effectiveness to combat heat stress. In addition, a remarkable proportion of 91 per cent of subjects prefer to use this newly designed HCV as a cooling measure during rest. The power to alleviate perceptual heat stain (PeSA) in VEST is about twice of that by rest, which means HCV can notably improve the workers' perceptual heat strain in a limited resting duration. However, the strain alleviation power of HCV nearly remains unchanged with the prolonged rest duration. Thus, the optimal work-rest schedule needs to be investigated in a further study.

Comparison of heat strain recovery in different anti-heat stress clothing ensembles after work to exhaustion.

A hot environment combined with physically demanding tasks can subject workers to a higher risk of heat stress. A series of regulations and guidelines have been proposed to design appropriate anti-heat stress work uniform to reduce body heat strain. The present study aimed to examine heat strain recovery in different anti-heat stress clothing ensembles after work to exhaustion in the heat. 10 healthy males performed intermittent treadmill running/walking to exhaustion, followed by 30min passive recovery sitting in a climatic chamber, which simulated the hot and humid outdoor environment (34°C temperature, 60% relative humidity, 0.3m/s air velocity, and 450W/m2 solar radiation). The participants took part in five wear trials in counter-balanced order, including Sportswear, CIC Uniform, NEW Uniform, ICEBANK Cooling Vest, and NEW Cooling Vest, which have different levels of cooling capacity. Core temperature, skin temperature, heart rate, sweat loss, ratings of perceived exertion, and thermal sensations were measured throughout the entire heat exposure period. Physiological heat strain indices, including the physiological strain index (PhSI) and the perceptual strain index (PeSI), were used as a yardstick to quantify and compare the rate of recovery. Significantly lower physiological strain was observed in the newly developed NEW Uniform and NEW Cooling Vest groups compared with the commonly worn CIC Uniform group during recovery. At the end of the recovery period, participants in NEW Cooling Vest achieved the highest recovery (42.18% in PhSI and 81.08% in PeSI), followed by ICEBANK Cooling Vest, Sportswear, NEW Uniform, and CIC Uniform. The cooling capacity of anti-heat stress clothing ensembles and the recovery time significantly affect the rate of recovery in PhSI and PeSI, which may benefit the industry by formulating the appropriate work-rest schedule by considering the clothing effect.

Effects of Heat Stress on Construction Labor Productivity in Hong Kong: A Case Study of Rebar Workers.

Global warming is bringing more frequent and severe heat waves, and the result will be serious for vulnerable populations such as construction workers. Excessive heat stress has profound effects on physiological responses, which cause occupational injuries, fatalities and low productivity. Construction workers are particularly affected by heat stress, because of the body heat production caused by physically demanding tasks, and hot and humid working conditions. Field studies were conducted between August and September 2016 at two construction training grounds in Hong Kong. Onsite wet-bulb globe temperature (WBGT), workers' heart rate (HR), and labor productivity were measured and monitored. Based on the 378 data sets of synchronized environmental, physiological, construction labor productivity (CLP), and personal variables, a CLP-heat stress model was established. It was found that WBGT, percentage of maximum HR, age, work duration, and alcohol drinking habits were determining factors for predicting the CLP (adjusted R² = 0.68, p < 0.05). The model revealed that heat stress reduces CLP, with the percentage of direct work time decreasing by 0.33% when the WBGT increased by 1 °C. The findings in this study extend the existing practice notes by providing scientific data that may be of benefit to the industry in producing solid guidelines for working in hot weather.