An aging workforce and injury in the construction industry

Systematic analysis of the occurrence characteristics and impact on hospitalization costs of trauma complications

BACKGROUND

Trauma complications increase the burden of disease and hospitalization costs for patients. More research evidence is needed on how to more effectively prevent these complications and reduce hospitalization costs based on the characteristics of trauma patients. Therefore, this study will systematically analyze the characteristics of trauma complications and their specific impact on hospitalization costs.

METHODS

This is a multi-center retrospective study of trauma hospitalizations from 2018 to 2023. Associations between population characteristics, trauma features, and each complication occurrence were investigated using multiple correspondence analysis. Logistic regression analysis assessed factors influencing trauma complications. Additionally, a generalized linear model analyzed the relative increase in hospital costs for each complication.

RESULTS

A total of 48,032 trauma patients were included, with 22.0% experiencing at least one complication. Thrombosis is more prevalent among elderly women (aged ≥65) with pelvic and extremity trauma. In men aged 18-44 years, respiratory insufficiency and post-traumatic anemia primarily occurred in cases of head injuries and multiple injuries. Chest and multiple injuries predispose people aged 45-64 to pneumonia and electrolyte disorders. Body surface injuries are prone to surgical site infections. Complications resulted in an average relative increase in overall hospitalization costs of 1.32-fold, with thrombosis (1.58-fold), respiratory insufficiency (1.11-fold), post-traumatic anemia (0.58-fold), surgical site infection (0.48-fold), pneumonia (0.53-fold), electrolyte disorders (0.47-fold).

CONCLUSIONS

This study systematically analyzed the occurrence characteristics of trauma complications and the burden trends of hospitalization costs due to complications, providing a reference for the formulation of trauma classification and management strategies.

Characteristics of Work-related Fatal Injuries Among Aged Workers in Republic of Korea

Objectives

The present paper aimed to examine whether an aging workforce is associated with an increase in work-related fatal injuries and to explore the underlying reasons for this potential increase.

Material and methods

Aged workers were defined as those who were at least 55 years old. Work-related fatalities were assessed in aged and young workers who were registered with the workers' compensation system in 2021 in the Republic of Korea. Total waged workers, based on raw data from the Local Area Labor Force Survey in 2021, were used as the denominator to estimate the work-related fatality rates.

Results

Most work-related fatalities in the aged workers occurred among individuals working in the "construction sector" (58.9%), those with "elementary occupations (unskilled workers)" (46.1%), and those with the employment status of "daily worker" (60.8%). The estimated incidence (0.973/10,000) of work-related fatalities among aged workers was about four times higher than that (0.239/10,000) among younger workers. "Falling," "collision," "struck by an object," and "trip and slip" were more frequent types of work-related fatalities among aged workers relative to young workers. The category of "buildings, structures, and surfaces" was a more frequent cause of work-related fatalities among aged workers than among young workers.

Conclusions

Aged workers had a higher incidence of work-related fatalities than young workers. Frequent engagement in precarious employment and jobs, coupled with the greater physical vulnerability of aged workers, were likely causes of their higher level of work-related fatal injuries.

Particulate matter reduction efficiency analysis of sprinkler system as targeted control measures for construction activity

Air pollution caused by the construction industry in the form of particulate matter (PM) has increased to an alarming level. The effects on the health of construction workers are found to be hazardous despite the current advancement in construction methods and practices. In particular, the efficiency of existing control measures for reducing PM from various construction activities has not been improved to the desired level. This study investigated the factors that influence the efficiency of a sprinkler system-based control measure when water spraying and dust suppressant solutions are used. The real-time PM exposure was measured during hollow-block cutting activity using Alphanese OPC-N3 sensors in dust chamber. The dust suppressant suppresses dust particles by initially forming a solidified film on the particle surface, and the high cohesion of this film enhances the suppression rate by promoting dust particle coagulation. It was observed that when using a dust suppressant, the PM concentration at 100 bar exceeded concentrations at other pressures, resulting in increased efficacy in reducing PM10. Additionally, water spraying at 115 bar was determined to be the optimal control measure for achieving a significant percentage of PM reduction in a shorter period. These findings can be highly beneficial if the water sprinkler system can be modified into a smart mobility-based sprinkler system either ground-based or drone-based at construction sites in improving PM reduction efficiency particularly on high PM emitting activities.

Perceived benefits, barriers, perceptions, and readiness to use exoskeletons in the construction industry: Differences by demographic characteristics

Exoskeletons (EXOs) are a promising wearable intervention to reduce work-related musculoskeletal disorder risks among construction workers. However, the adoption of EXOs may differ with demographic characteristics. Survey data (n = 361) were collected from construction industry stakeholders and a summation score method was used to summarize respondent's benefits and barriers to EXO use, along with perceptions and readiness to use. Responses were stratified by race (White vs. non-White), sex (male vs. female), and age (<47 years vs. ≥47 years). Both a higher Benefits score and a higher Perceptions score were significantly and positively associated with a higher Readiness to Use score. There were also significant differences in perceived barriers to EXO use by race and sex. These results demonstrate substantial interest in EXO use but also emphasize the need to ensure proportionate access to the potential benefits of EXO technology.

A Detailed Analysis of Workplace Foot and Ankle Injuries

INTRODUCTION

This study analyzes the incidence rate and median workdays missed due to foot and ankle injuries across age groups, sexes, and industries.

METHODS

Workplace injury data from 2003 to 2019 were obtained using the Nonfatal Cases Involving Day Away from Work: Selected Characteristics database provided by the Bureau of Labor Statistics (BLS). The data were grouped by injury location (ie, foot, ankle), injury type (ie, fracture, sprain), and industry, and reported with injury incidence rates and median workdays missed.

RESULTS

The incidence rate of foot and ankle injuries significantly decreased from 2003 to 2019 (P < .001). With increasing age, the incidence rate of foot and ankle injuries decreased (P < .001) and median workdays missed increased (P < .001). Men had significantly higher rates of foot and ankle injuries (P < .001). Agriculture, forestry, fishing, and hunting (foot=10.23%, ankle=10.41%); construction (foot=8.14%, ankle=8.68%); and transportation and warehousing (foot=11.06%, ankle=13.80%) industries had the highest injury incidence rates. Transportation and warehousing (foot=16.8 days, ankle=16.3 days), mining (foot=44.9 days, ankle=17.1 days), and utilities (foot=26.7 days, ankle=24.4 days) industries had the highest median workdays missed.

CONCLUSION

Increased incidence and severity of workplace foot and ankle injuries are associated with male sex and heavy labor industries. Age was positively associated with severity and negatively associated with incidence of workplace ankle injuries.

LEVELS OF EVIDENCE

Level III, Retrospective cohort study.

Factors affecting work-related non-fatal injuries among aged workers in South Korea

Introduction

The objective of this paper is to investigate whether an aging workforce is associated with an increase in work-related non-fatal injuries and to explore the underlying reasons for this potential increase.

Methods

Aged workers were defined as those who were at least 55-years-old. Work-related non-fatal injuries were assessed in aged and young workers who were registered with the workers' compensation system from 2017 to 2021 of South Korea.

Results

The mean estimated rate of work-related non-fatal injuries of aged workers (0.88/100) was about 2.5-times higher than that of younger workers (0.35/100). Most work-related non-fatal injuries in the older adults were in individuals working in the "construction sector" (36.0%), those with "elementary occupations (unskilled workers)" (45.0%), and those with employment status of "daily worker" (44.0%). "Trip & slip" (28.7%) and "falling" (19.6%) were more frequent types of work-related non-fatal injuries in aged workers relative to young workers. The category of "buildings, structures, and surfaces" was a more frequent cause of work-related non-fatal injuries in aged workers than young workers.

Discussion

The incidence of non-fatal work-related injuries is higher among aged workers compared to their younger counterparts. The increased occurrence of aged workers participating in precarious employment and jobs, along with the greater physical vulnerability, is likely the cause of their higher rate of work-related non-fatal injuries.

Occupational Injuries Among Construction Workers by Age and Related Economic Loss: Findings From Ohio Workers' Compensation, USA: 2007-2017

Background

This study examined age-group differences in the rate, severity, and cost of injuries among construction workers to support evidence-based worker safety and health interventions in the construction industry.

Methods

Ohio workers' compensation claims for construction workers were used to estimate claim rates and costs by age group. We analyzed claims data auto-coded into five event/exposure categories: transportation incidents; slips, trips, and falls (STFs); exposure to harmful substances and environments; contact with objects and equipment (COB); overexertion and bodily reaction. American Community Survey data were used to determine the percentage of workers in each age group.

Results

From 2007-2017, among 72,416 accepted injury claims for ∼166,000 construction full-time equivalent (FTE) per year, nearly half were caused by COB, followed by STFs (20%) and overexertion (20%). Claim rates related to COB and exposure to harmful substances and environments were highest among those 18-24 years old, with claim rates of 313.5 and 25.9 per 10,000 FTE, respectively. STFs increased with age, with the highest claim rates for those 55-64 years old (94.2 claims per 10,000 FTE). Overexertion claim rates increased and then declined with age, with the highest claim rate for those 35-44 years old (87.3 per 10,000 FTE). While younger workers had higher injury rates, older workers had higher proportions of lost-time claims and higher costs per claim. The total cost per FTE was highest for those 45-54 years old ($1,122 per FTE).

Conclusion

The variation in rates of injury types by age suggests that age-specific prevention strategies may be useful.

The Cost Burden of Safety Risk Incidents on Construction: A Probabilistic Quantification Method

The construction sector is vulnerable to safety risk incidents due to its dynamic nature. Although numerous research efforts and technological advancements have focused on addressing workplace injuries, most of the studies perform empirical and deterministic postimpact evaluations on construction project performance. The effective modeling of the safety risk impacts on project performance provides decisionmakers with a valuable tool toward incidents prevention and proper safety risk management. Therefore, this study collected Australian incident records from the construction industry from 2016 onwards and conducted discrete event simulation to quantitatively measure the impact of safety risk incidents on project cost performance. Moreover, this study investigated the correlation between safety risk incidents and the age of injured workers. The findings show a strong correlation between the middle-aged workforce and the severity of incidents on project cost overruns. The ex-ante, nondeterministic analysis of safety risk impacts on project performance provides insightful results that will advance safety management theory in the direction of achieving zero harm workplace environments.

Becoming the employer of choice: anticipating and preparing for a graying workforce in industry

The recent shift in the labor force that has occurred in many developed countries has been greater than any shift prior to 2020. This shift was caused by reduced birthrates coupled with the rising percentage of mature workers in the labor force, compounded by the 2020 global shut-down due to Covid-19. Managers and HR directors need to act now to gather the necessary data on their employees and their company's projected labor needs to accurately plan for their short- and long-term labor needs. A partial solution for this impending labor shortage is for companies to proactively become the "employer of choice" for their graying workforce by making necessary accommodations to retain and recruit mature workers. The concept of employer of choice relates to creating a work climate that attracts and retains workers to a specific employment opportunity. This article focuses on the steps that can be taken by employers to minimize the impact of this looming labor shortage on their company as well as on the overall economy. The article also provides background on some of the reasons why many mature workers want and need to continue working and the imperatives as to why immediate action on the part of employers is necessary.

Empirical Analysis of Dust Health Impacts on Construction Workers Considering Work Types

In the construction industry, workers are exposed to hazardous emissions, such as dust, and various diseases, such as chronic obstructive pulmonary disease (COPD), which affect workers. There is, however, a lack of studies that evaluate the dust that workers are exposed to, taking into account different factors of dust. Therefore, this study aims to estimate the amount of dust construction workers are exposed to by considering different factors of dust emission and to assess the health and economic impact of dust emissions. This study is conducted in three steps: (1) scope definition, (2) definition of worker dust exposure, and (3) health impact assessment. As a result, dust concentrations from the energy used, the atmosphere, and during construction activities were 1.01 × 10−5 µg/m3, 37.50 µg/m3, and 1.33 × 104 µg/m3 respectively. Earthwork had the highest dust concentration of 3.85 × 103 µg/m3. The total added number of disability-adjusted life years (DALY) of workers was 0.0542a with an economic cost of $13,691.00. The contributions of this study are the accurate assessment of the amount of dust workers are exposed to and the development of policies to help compensate construction workers suffering from dust emission-related diseases.

They built this city-construction workers injured in Delhi, India: cross-sectional analysis of First Information Reports of the Delhi Police 2016-2018

Background

Construction workers are 3–4 times more likely than other workers to die from accidents at work—however, in the developing world, the risks associated with construction work may be 6 times greater. India does not publish occupational injury statistics, and so little is known about construction workers injured. We aimed to use Indian police records to describe the epidemiology of construction site injuries in Delhi and to thus generate knowledge that may help to control the burden of injuries to construction workers in India and in other developing countries.

Methods

This was a cross-sectional analysis of accident records maintained by the Delhi Police. We included all construction workers reported to have been killed or injured in construction site accidents in Delhi during the period 2016–2018. We used multivariable logistic regression models to investigate associations between injury severity (fatal vs. non-fatal injury) and exposure variables whilst adjusting for a priori risk factors. We also estimated the number of Delhi construction workers in total and by trade to generate estimates of worker injury rates per 100,000 workers per year.

Results

There were 929 construction site accidents within the study period, in which 1,217 workers and children were reported to have sustained injuries: 356 (29%) were fatal and 861 (71%) were non-fatal. One-eighth of injuries were sustained by females. Most occurred in the Rainy season; most were sustained during the construction of buildings. The most frequent causes were the collapse of an old building, the collapse of a new building under construction, and electric shocks. Electricians were more likely than unskilled workers to suffer a fatal injury (adjOR 2.5; 95% CI: 0.87–6.97), and there were more electrical shocks than electricians injured. The odds of a fatal injury were statistically significantly lower in Central districts than in the less developed, peripheral districts.

Conclusions

Construction site injuries are an unintended health impact of urbanisation. Women undertake manual work alongside men on construction sites in Delhi, and many suffer injuries as a consequence: an eighth of the injuries were sustained by females. Children accompanying their working parents on construction sites are also at risk. Two main hazards to construction workers in Delhi were building collapses and electrical shocks. Electricians were over twice as likely as unskilled workers to suffer a fatal injury, and electrical work would appear to be undertaken by a multitude of occupations. As the global urban population increases over the coming decades, so too will the burden of injuries to construction workers. The introduction and enforcement of occupational safety, health, and working conditions laws in India and in other rapidly developing countries will be necessary to help to control this injury burden to construction workers.

Construction Accidents in Spain: Implications for an Aging Workforce

Construction workers are getting older. In the European Union, the percentage of workers over 50 grew from 24.7% in 2011 to 31.5% in 2018, in Spain from 20.4% to 31.2%. Objective. Identify trends and detailed patterns of accidents of older construction workers compared to other age groups. Data and Method. We analyzed construction accidents in Spain from 2011 to 2018 (N = 455,491). The number of accidents and lost working days (LWD) were broken down by occupation, seniority, company size, temporal variables (weekday, hour), trigger, and body part injured and compared for different age groups. Results. Although older worker had fewer accidents, the consequences of accidents were more serious. Those over 50 years had 84% more lost working days (LWD) than those under 24 years, 48% more than those between 25 and 39 years, and 21% more than those between 40 and 49 years. (1) Occupation: the percentage of accidents grew with age for supervisors, lorry drivers, and bricklayers. (2) Seniority: the least experienced (less than 6 months) and the most experienced (more than 6 years) had the most LWD. (3) Company size: there are 24.5% of accidents in companies of less than four workers. (4) Trigger: older workers suffered more falls, both from height and at the same level. (5) Time: the percentage of accidents in those over 50 was higher on Thursdays and Fridays, in the afternoons from 4 to 7 p.m., and after four hours of work. (6) Injury: this shows the longest absences for shoulder injuries for those over 50 years, with an average of 70 LWD.

Latin American Agricultural Workers' Job Demands and Resources and the Association With Health Behaviors at Work and Overall Health

In the present study, we describe the job demands and job resources (JD-R) experienced by agricultural workers in three Latin American countries and their relationship to proactive health behaviors at work and overall health. Following previous research on the JD-R model, we hypothesized that job demands (H1) would be negatively related to agricultural workers' self-reported overall health. On the other hand, we hypothesized that job resources (H2) would be positively related to agricultural workers' overall health. Furthermore, we hypothesized (H3) that workers' engagement in jobsite health promotion practices via their proactive health behaviors at work would partially mediate the relationship between workers' job resources and job demands and overall health. We also had a research question (R1) about whether there were differences by type of job held. The sample of workers who participated in this study (N = 1,861) worked in Mexico, Guatemala, and Nicaragua for one large agribusiness that produces sugar cane. They worked in two distinct areas: company administration and agricultural operations. We administered employee health and safety culture surveys using survey methods tailored to meet the needs of both types of workers. Stratified path analysis models were used to test study hypotheses. In general, we found support for hypotheses 1 and 2. For example, operations workers reported more physically demanding jobs and administrative workers reported more work-related stress. Regardless, the existence of high job demands was associated with poorer overall health amongst both types of workers. We found that workers in more health-supportive work environments perform more proactive health behaviors at work, regardless of their role within the organization. However, hypothesis 3 was not supported as proactive health behaviors at work was not associated with overall health. We discuss future research needs in terms of evaluating these hypotheses amongst workers employed by small- and medium-sized agribusinesses as well as those in the informal economy in Latin America. We also discuss important implications for agribusinesses seeking to develop health promotion programs that meet the needs of all workers.

Pilot of a Community Health Worker Video Intervention for Immigrant Day Laborers at Occupational Health Risk

Significance: Immigrant day laborers suffer from disproportionate occupational health risks from hazardous reconstruction jobs after natural disasters.

Methods: We conducted a randomized controlled trial of a short-video educational intervention to improve safety knowledge and intent to engage in safety preventive behaviors among 98 Hispanic day laborers (49 randomized to video and 49 control). The short video featured a male promotor and a female promotora who narrated 3 stories of day laborers who were injured while doing construction work in post-Katrina New Orleans. The main outcome measures were changes in scores for day laborer-reported safety knowledge and safety behaviors derived from interviewer-delivered baseline and post-intervention surveys.

Results: Video participants reported improvement in overall average safety knowledge score (mean score of 11.3 out of a max score of 12 or 94% when standardized to 0–100% scale), as compared to the control group (mean score of 8.6 or 72%) who were not offered the video (p < 0.00001). The intervention was highly successful in workers stating that they learned and were willing to change their safety preventive behaviors to reduce their occupational risk. The average safety behavior score was higher among those watching the video (17.2 out of a max of 22 or 78.1% when standardized on a scale 0–100%) as compared to control (14.5 or 65.9%) (p = 0.0024).

Conclusion: A short video intervention can improve knowledge and intent to engage in preventive behaviors among Hispanic workers for which there is a dearth of construction safety preventive research.

Factors for the Automation of the Creation of Virtual Reality Experiences to Raise Awareness of Occupational Hazards on Construction Sites

Two of the differential characteristics of the AECO sector (architecture, engineering, construction and operation) are barriers for the mass creation of training materials for its workers. On the one hand, the workplace is unique and changing over time; on the other, the aging trend of its workers and the unattractive nature of the industry for new generations of professionals. These two problems can be tackled by virtual reality technologies, which allow the agile creation of all kinds of scenarios, while their current technology may be attractive to young people and intuitive for everyone. This work shows the results of an investigation that seeks to provide automated tools based on virtual reality experiences to support learning in occupational risk prevention. This objective is part of the development of a culture for prevention, which allows the treatment of the human factor, with all its complexity and casuistry. The proposal includes the development of a process and tools that allow replicating the specific scenario where the work will be carried out, incorporating risks and probable incidents, systematically establishing cause-effect relationships, incorporating a narrative (storytelling) that provides emotional meaning to users and Lastly, the creation of a workflow that facilitates the agile development of these virtual reality experiences for each specific work.

Workers' Compensation Claim Rates and Costs for Musculoskeletal Disorders Related to Overexertion Among Construction Workers - Ohio, 2007-2017

Overexertion is a leading cause of work-related musculoskeletal disorders (WMSDs) among construction workers. Nearly 90% of construction jobs require manual handling of materials for approximately one half of the worker's time (1). In 2015, overexertion from lifting and lowering materials caused 30% of WMSDs among construction workers; overexertion involving pushing, pulling, holding, carrying, and catching materials caused an additional 37% of WMSDs (1). This study examined the rate and cost of WMSD claims from overexertion among Ohio construction workers during 2007-2017. Workers' compensation claims related to overexertion that were submitted to the Ohio Bureau of Worker's Compensation (OHBWC) by workers in the construction industry for injuries and illnesses occurring during 2007-2017 were analyzed. Rates and costs of allowed claims were measured by age group. Workers aged 35-44 years experienced the highest claim rate: 63 per 10,000 full-time employees (FTEs) for WMSDs from overexertion. However, claims by workers aged 45-54 years and 55-64 years were more costly on average and resulted in more days away from work. Ergonomic design improvements and interventions are needed to ensure that the majority of construction workers can safely perform jobs throughout their careers. Age-specific WMSD prevention and risk communication efforts also might be helpful.

Smart Green Prefabrication: Sustainability Performances of Industrialized Building Technologies

There is an urgent need to increase the environmental, economic, and social sustainability of buildings. Indeed, construction has one of the lowest rates of sustainability among productive sectors, associated with high energy demand and pollutant emissions, frequent cost increase and time delays, and poor and unsafe working conditions. Building prefabrication is a construction technique that can enhance the sustainability of buildings, in terms of predictability, product and process quality, and increased safety for workers. Recently, new approaches and concepts such as Industry 4.0 (Construction 4.0) and circularity of resources emerged in the field of prefabrication to potentiate the benefits of off-site construction. In this scenario, the scope of the work is to analyze the state of the art in the field of prefabricated building technologies in the light of these innovations and to evaluate their performances from a sustainability perspective. The work has been developed in two phases: (1) analysis of 13 case studies of prefabricated technologies in Europe; (2) comparative assessment of their sustainability performances according to 21 qualitative parameters. Based on the results of the work, a set of guidelines is proposed as the outcome, i.e., suggested strategies and approaches for designers and industry professionals that can be used to enhance the sustainability of prefabrication.

A review on health risk assessment of PM in the construction industry - Current situation and future directions

Particulate matter (PM) is one of the primary pollutants of the environment. The amount of PM discharged from construction projects is considerably high; it generates 70-80% of the overall PM. The composition of PM is complex and may contain various toxic substances that have severe health effects on human health. Existing health risk assessment in the construction industry lacks the efficiency to reduce the risk level of PM exposure. This study systematically reviews literature in this research area to understand the primary reasons which generates PM health risk assessments. The authors reviewed health risk assessment studies in the construction industry to analyze the current situation, and then reviewed health risk assessment studies from four different industries to compare the advancement of research and outcomes in all the five industries. From the study it is understood that the area of research related to ambient air were more developed compared to those in other areas due to their sampling methods and the size of the PM studied. From the findings of the systematic review, it is understood that majority of the risk assessment studies still rely on a two decade-old system and neglect recent research findings pertaining inhalation rate and size of PM. To overcome this, the level of risk involved in various common construction activities needs to be explored using real-time location-based PM monitoring and real-time inhalation monitoring methods. The findings of this review will help researchers gain a better perspective while conducting occupational health risk studies in the construction industry.

Risk Perception and Its Influencing Factors among Construction Workers in Malawi

This study employed a deductive research approach and a survey strategy to assess risk perception and its influencing factors among construction workers in Malawi. Three specific construction hazards and their associated risks were selected. The hazards were “working at height (WAH)” “manual handling of loads (MHL)” and “heavy workload or intense pressure to be more productive (HWP).” The study engaged multistage sampling of 376 subjects. Univariate analysis, factor analysis and multiple linear regressions were performed in order to determine the main influencing factors among the independent variables. The study established that workers were aware of risks posed by their work. The majority perceived the risk associated with WAH, MHL and HWP as very high (62.7%, =8.80 ± 1.95); (48.5%, =8.10 ± 2.38); (57.9%, =8.49 ± 2.22) respectively. The study identified six factors as variables that showed a significant effect on workers’ perception of risk (p < 0.05). These factors were: “dreaded factor,” “avoidability and controllability,” “expert knowledge,” “personal knowledge,” “education level,” and “age”. It is concluded that contractors in the Malawian construction industry should integrate analysis of behaviors and risk perception of the workers and other players to guide the identification of better health and safety interventions at their worksites.

The Effects of Psychological Factors on Perceptions of Productivity in Construction Sites in Japan by Worker Age

The construction industry is a work environment that poses many dangers to workers, with many hidden factors that affect work awareness. It is important for construction companies to ensure a balance between productivity and safety in the work environment. The purpose of this study was to identify relationships between the feeling of safety in the work environment, proactive work behavior, job satisfaction, work skills, team performance, and health risk indicators, such as heart rate, among construction workers of different ages. Based on previous research, we examined the hypothetical perception model. We then administered a questionnaire survey to construction workers (N = 357) employed at a Japanese construction company. Using structural equation modeling (SEM), we investigated the impact of health risk indicators on worker perceptions among young and older workers. The results showed that workers’ heart rate and body mass index (BMI) had a negative effect on the feeling of safety and proactive work behavior among older workers, but showed no significant relationship among young workers. However, regardless of workers’ age, it was clear that the feeling of safety affects job satisfaction, and that work skills and proactive work behaviors affect perceptions regarding team performance.

Considerations for physical employment standards in the aging workforce

BACKGROUND

If current population and health trends continue, workplace demographics will look significantly different by the turn of the century. Organizations will no longer have a steady pipeline of younger workers and will likely need to rely on older workers to remain competitive in the global marketplace. The future multi-generational workforce will bring with it the challenge of maximizing contributions from each generation whilst at the same time addressing the health, safety and wellbeing needs of all workers.

OBJECTIVE

This review provides an insight into aging and older workers, and presents recommendations to promote worker longevity.

METHODS

This narrative review draws on evidence from 108 published sources.

RESULTS

The relationship between age and work is not simple; factors including the physical nature of the job and worker's health and fitness interact with age to either increase or decrease the potential effect of age. Evidence suggests that the issues arising from an aging workforce can be managed through polices that focus on active aging through: attitude management; flexible working and the provision of occupational health.

CONCLUSION

The integration of such interventions would require company and organizational commitment from the top down with educational programs at all levels to ensure understanding and participation.

Predisposing factors influencing occupational injury among frontline building construction workers in Ghana

OBJECTIVE

This study aims to examine the predisposing factors influencing occupational injuries among frontline construction workers in Ghana. A cross-sectional survey was carried out with 634 frontline construction workers in Kumasi metropolis of Ghana using a structured questionnaire. The study was conducted from December 2016 to June 2017 using a household-based approach. The respondents were selected through a two-stage sampling approach. A multivariate logistics regression model was employed to examine the association between risk factors and injury. Data was analyzed employing descriptive and inferential statistics with STATA version 14.

RESULTS

The study found an injury prevalence of 57.91% among the workers. Open Wounds (37.29%) and fractures (6.78%) were the common and least injuries recorded respectively. The proximal factors (age, sex of worker, income) and distal factors (e.g. work structure, trade specialization, working hours, job/task location, and monthly off days) were risk factors for occupational injuries among frontline construction workers. The study recommends that policymakers and occupational health experts should incorporate the proximal and distal factors in the design of injury prevention as well as management strategies.

Occupational safety in the construction industry

BACKGROUND

The paper is a research review focusing on occupational safety in the construction industry.

OBJECTIVE

The purpose is to present research that highlights the areas of occupational safety and risks and to identify areas where research is lacking.

METHODS

146 articles from scientific journals, mainly covering the construction industry in Europe, Canada, USA, Australia and Japan have been studied. The findings are presented under 11 categories: accident statistics; individual factors; legislation and regulations; ethical considerations; risk management; leadership, management, organization; competence; safety design; cost-benefit calculations; programs and models; and technical solutions.

RESULTS

The research is dominated by initiatives from researchers and government authorities, while the construction industry only appears as the object for the research. There is a scarcity of research on integrated systems encompassing subcontractors, as well as a lack of research with sociological perspectives on accidents. Furthermore, only a few studies have applied a gender perspective on safety in construction, i.e. there is a need of further research in this particular area.

CONCLUSIONS

A range of initiatives have been taken to increase safety in the construction industry and the initiatives are mainly reported to be successful. There are some cultural differences, but basically researchers present similar results regardless of country.

The Risk Factor of Age in Construction Accidents: Important at Present and Fundamental in the Future

Occupational accidents in the construction sector are analyzed in this study of the relation between the age of the injured worker, days off work due to the injury, and accident severity. A further aim is to establish whether accumulated fatigue during the working day and throughout the week has a similar effect on all workers, regardless of age. A total of three million four hundred and thirty-eight thousand, one hundred and forty-five (3,438,145) accidents are analyzed in this study; the total of all accidents are notified in Spain by workers from the sector over the period 1996-2015. The results confirmed a direct link between worker age and both days off work due to the injury and accident severity. They also confirmed that the workers injured in accidents in the afternoon hours were older than the workers injured in the morning hours. In consequence, the average number of days off work due to injury following an accident of the older workers was also larger and the accidents are more severe. Likewise, the workers injured on a Friday were of an older average age than those injured on a Monday. In consequence, the average number of days off work due to injury on the last day of the week was also higher and the accidents were of more severity. All the above-mentioned differences were statistically significant.

The Work Ability of Hong Kong Construction Workers in Relation to Individual and Work-Related Factors

The shortage in Hong Kong of construction workers is expected to worsen in future due to the aging population and increasing construction activity. Construction work is dangerous and to help reduce the premature loss of construction workers due to work-related disabilities, this study measured the work ability of 420 Hong Kong construction workers with a Work Ability Index (WAI) which can be used to predict present and future work performance. Given the importance of WAI, in this study the effects of individual and work-related factors on WAI were examined to develop and validate a WAI model to predict how individual and work-related factors affect work ability. The findings will be useful for formulating a pragmatic intervention program to improve the work ability of construction workers and keep them in the work force.

Relating Older Workers' Injuries to the Mismatch Between Physical Ability and Job Demands

OBJECTIVE

We examined the association between job demand and occupational injury among older workers.

METHODS

Participants were workers aged 50+ enrolled in the Health and Retirement Study, 2010 to 2014. Participants reported physical ability within three domains: physical effort, stooping/kneeling/crouching, and lifting. To measure subjective job demand, participants rated their job's demands within domains. We generated objective job demand measures through the Occupational Information Network (ONET). Using Poisson regression, we modeled the association between physical ability, job demand, and self-reported occupational injury. A second model explored interaction between job demand and physical ability.

RESULTS

The injury rate was 22/1000 worker-years. Higher job demand was associated with increased injury risk. Within high job demands, lower physical ability was associated with increased injury risk.

CONCLUSIONS

Older workers whose physical abilities do not meet job demands face increased injury risk.

The prevalence of musculoskeletal symptoms in the construction industry: a systematic review and meta-analysis

PURPOSE

Although individual studies have reported high prevalence of musculoskeletal symptoms (MSS) among construction workers, no systematic review has summarized their prevalence rates. Accordingly, this systematic review/meta-analysis aimed to synthesize MSS prevalence in different construction trades, gender and age groups, which may help develop specific ergonomic interventions.

METHODS

Nine databases were searched for articles related to the research objective. Two reviewers independently screened citations, extracted information and conducted quality assessment of the included studies. Meta-analyses were conducted on clinical and statistical homogenous data.

RESULTS

Thirty-five out of 1130 potential citations were included reporting diverse types of period prevalence and case definitions. Only the 1-year prevalence rates of MSS (defined as at least one episode of pain/MSS in the last year) at nine anatomical regions had sufficient homogeneous data for meta-analysis. Specifically, the 1-year prevalence of MSS was 51.1% for lower back, 37.2% for knee, 32.4% for shoulder, 30.4% for wrist, 24.4% for neck, 24.0% for ankle/foot, 20.3% for elbow, 19.8% for upper back, and 15.1% for hip/thigh. Female workers demonstrated a higher prevalence of MSS while there was insufficient information on the prevalence of trade-specific or age-related MSS. The quality assessments revealed that many included studies estimated prevalence solely based on self-reported data, and did not report non-respondents' characteristics.

CONCLUSIONS

Lumbar, knee, shoulder, and wrist MSS are the most common symptoms among construction workers. Future studies should standardize the reporting of period prevalence of MSS in different construction trades to allow meta-analyses and to develop relevant MSS prevention program.

Injuries among electric power industry workers, 1995-2013

INTRODUCTION

Workers in the electric power industry face many risks of injury due to the high diversity of work tasks performed in potentially hazardous and unpredictable work environments.

METHOD

We calculated injury rates by age, sex, occupational group, and injury type among workers in the Electric Power Research Institute's (EPRI) Occupational Health and Safety Database (OHSD), which contains recordable injury, medical claims, and personnel data from 18 participating electric power companies from 1995 to 2013.

RESULTS

The OHSD includes a total of 63,193 injuries over 1,977,436 employee-years of follow-up, for an overall injury rate of 3.20 injuries per 100 employee-years. Annual injury rates steadily decreased from 1995 to 2000, increased sharply in 2001, and subsequently decreased to their lowest rate of 1.31 injuries per 100 employee-years in 2013. Occupations with the highest injury rates were welders (13.56 per 100 employee-years, 95% CI 12.74-14.37), meter readers (12.04 per 100 employee-years, 95% CI 11.77-12.31), and line workers (10.37 per 100 employee-years, 95% CI 10.19-10.56). Males had an overall higher injury rate compared to females (2.74 vs. 1.61 per 100 employee-years) although some occupations, such as meter reader, had higher injury rates for females. For all workers, injury rates were highest for those in the 21 to 30 age group (3.70 per 100 employee-years) and decreased with age. Welders and machinists did not follow this trend and had higher injury rates in the 65+ age group. There were 63 fatalities over the 1995 to 2013 period, with 21 fatalities (33.3%) occurring among line workers.

CONCLUSIONS

Although injury rates have decreased over time, certain high-risk groups remain (i.e., line workers, mechanics, young males, older welders and machinists, and female meter readers).

PRACTICAL APPLICATIONS

Protective measures and targeted safety programs may be warranted to ensure the safety of electric power workers.

The effect of demographic factors on occupational injuries

OBJECTIVES

In Finland about 120,000 occupational injuries occur annually, the cost of which is over EUR 2 billion per year. This is why it is reasonable to analyze the effect of demographic factors like gender, age, tenure and mother tongue on occupational injuries.

METHODS

The participants consisted of 1681 employees from four Finnish companies, who reported their injuries from the last 3 years.

RESULTS

Gender or mother tongue did not associate with injury involvement. Employees younger than 25 years of age were more often involved in injuries than employees aged over 55 (odds ratio [OR] = 2.69, 95% confidence interval [CI] [1.70, 4.23]). Employees with 2-10 years of experience in the company had a higher injury frequency than both novice and very experienced employees (OR = 2.01, 95% CI [1.60, 2.52]).

CONCLUSIONS

This study showed that age was a more important factor in injury involvement than gender, tenure or mother tongue. However, age was closely related to experience in the company. Prevention measures in the companies should thus focus on novice employees.

Age, human performance, and physical employment standards

The proportion of older workers has increased substantially in recent years, with over 25% of the Canadian labour force aged ≥55 years. Along with chronological age comes age-related declines in functional capacity associated with impairments to the cardiorespiratory and muscular systems. As a result, older workers are reported to exhibit reductions in work output and in the ability to perform and/or sustain the required effort when performing work tasks. However, research has presented some conflicting views on the consequences of aging in the workforce, as physically demanding occupations can be associated with improved or maintained physical function. Furthermore, the current methods for evaluating physical function in older workers often lack specificity and relevance to the actual work tasks, leading to an underestimation of physical capacity in the older worker. Nevertheless, industry often lacks the appropriate information and/or tools to accommodate the aging workforce, particularly in the context of physical employment standards. Ultimately, if appropriate workplace strategies and work performance standards are adopted to optimize the strengths and protect against the vulnerability of the aging workers, they can perform as effectively as their younger counterparts. Our aim in this review is to evaluate the impact of different individual (including physiological decline, chronic disease, lifestyle, and physical activity) and occupational (including shift work, sleep deprivation, and cold/heat exposure) factors on the physical decline of older workers, and therefore the risk of work-related injuries or illness.

Fatal traumatic brain injuries in the construction industry, 2003-2010

BACKGROUND

Research on fatal work-related traumatic brain injuries (TBIs) is limited. This study describes fatal TBIs in the US construction industry.

METHODS

Fatal TBIs were extracted from the Bureau of Labor Statistics Census of Fatal Occupational Injuries.

RESULTS

From 2003 to 2010, 2,210 fatal TBIs occurred in construction at a rate of 2.6 per 100,000 full-time equivalent (FTE) workers. Workers aged 65 years and older had the highest fatal TBI rates among all workers (7.9 per 100,000 FTE workers). Falls were the most frequent injury event (n = 1,269, 57%). Structural iron and steel workers and roofers had the highest fatal TBI rate per 100,000 FTE workers (13.7 and 11.2, respectively). Fall-related TBIs were the leading cause of death in these occupations.

CONCLUSIONS

A large percentage of TBIs in the construction industry were due to falls. Emphasis on safety interventions is needed to reduce these fall-related TBIs, especially among vulnerable workers.

An analysis of permanent work disability among construction sheet metal workers

BACKGROUND

Causes of permanent work disability in the sheet metal industry are not well characterized.

METHODS

Pension records were used to compare causes of disability among sheet metal workers and the U.S. working population. Subgroup analysis examined the major causes of sheet metal worker disability.

RESULTS

Musculoskeletal disorders (MSDs), circulatory disease, and injuries were leading causes of sheet metal worker disability (47.2%, 13.7%, 10.9% of awards, respectively). Award distribution differed from the U.S. working population (P < 0.0001); MSDs and injuries accounted for higher proportions of sheet metal worker awards, particularly at spine, shoulder, and knee.

CONCLUSIONS

Higher proportions of awards caused by MSD or injury among sheet metal workers may reflect higher rates of work-related injuries and MSDs, a high likelihood of disability with construction work given the same impairment, or higher prevalence of other conditions in the general population. Prevention requires task-specific ergonomic innovations and proven participatory interventions.

Non-reporting of work injuries and aspects of jobsite safety climate and behavioral-based safety elements among carpenters in Washington State

BACKGROUND

Declining work injury rates may reflect safer work conditions as well as under-reporting.

METHODS

Union carpenters were invited to participate in a mailed, cross-sectional survey designed to capture information about injury reporting practices. Prevalence of non-reporting and fear of repercussions for reporting were compared across exposure to behavioral-based safety elements and three domains of the Nordic Safety Climate Questionnaire (NOSACQ-50).

RESULTS

The majority (>75%) of the 1,155 participants felt they could report work-related injuries to their supervisor without fear of retribution, and most felt that the majority of injuries on their jobsites got reported. However, nearly half indicated it was best not to report minor injuries, and felt pressures to use their private insurance for work injury care. The prevalence of non-reporting and fear of reporting increased markedly with poorer measures of management safety justice (NOSACQ-50).

CONCLUSIONS

Formal and informal policies and practices on jobsites likely influence injury reporting.

Workers' compensation claims for musculoskeletal disorders and injuries of the upper extremity and knee among union carpenters in Washington State, 1989-2008

BACKGROUND

Numerous aspects of construction place workers at risk of musculoskeletal disorders and injuries (MSDIs). Work organization and the nature of MSDIs create surveillance challenges.

METHODS

By linking union records with workers' compensation claims, we examined 20-year patterns of MSDIs involving the upper extremity (UE) and the knee among a large carpenter cohort.

RESULTS

MSDIs were common and accounted for a disproportionate share of paid lost work time (PLT) claims; UE MSDIs were three times more common than those of the knee. Rates declined markedly over time and were most pronounced for MSDIs of the knee with PLT. Patterns of risk varied by extremity, as well as by age, gender, union tenure, and predominant work. Carpenters in drywall installation accounted for the greatest public health burden.

CONCLUSIONS

A combination of factors likely account for the patterns observed over time and across worker characteristics. Drywall installers are an intervention priority.

Long-term health outcomes of work-related injuries among construction workers--findings from the National Longitudinal Survey of Youth

BACKGROUND

This study examined the relationship between work-related injuries and health outcomes among a cohort of blue-collar construction workers.

MATERIALS AND METHODS

Data were from the National Longitudinal Survey of Youth, 1979 cohort (NLSY79; n = 12,686). A range of health outcomes among blue-collar construction workers (n = 1,435) were measured when they turned age 40 (1998-2006) and stratified by these workers' prior work-related injury status between 1988 and 2000. Univariate and multivariate analyses were conducted to measure differences among subgroups.

RESULTS

About 38% of the construction cohort reported injuries resulting in days away from work (DAFW); another 15% were injured but reported no DAFW (NDAFW). At age 40, an average of 10 years after injury, those with DAFW injury had worse self-reported general health and mental health, and more diagnosed conditions and functional limitations than those without injury. This difference was statistically significant after controlling for major demographics.

DISCUSSION

Adverse health effects from occupational injury among construction workers persist longer than previously documented.

Control Method for Power Assisted Cart Using Walking Effect Prediction Aimed at Improvement of Load Reduction Ratio

<div class=""abs_img""><img src=""[disp_template_path]/JRM/abst-image/00260006/11.jpg"" width=""300"" />Proposed LRRC concept</div> In previous work, we proposed controlling powerassisted carts by using a motor torque limiter that achieves the desired load-reduction ratio even if torque saturates. We assumed, however, that the operator accelerates smoothly up to the target speed, so that when velocity is affected largely by the input force of walking, prediction error becomes large and the target load reduction ratio was not achieved. To solve this problem, we propose an improving the achievement rate of the target load reduction ratio in two steps, first, by predicting the number of steps toward target speed from initial input and, second, by switching the prediction model. We use cart input force and speed to predict operator acceleration patterns. Our proposal predicts operator needs and delivers the desired loadreduction ratio by predicting operation. Results show that the achievement rate of the target load-reduction ratio is improved by using our proposed control. In other words, applying our proposal improves the short available time of power-assisted carts. </span>

Rates of and circumstances surrounding work-related falls from height among union drywall carpenters in Washington State, 1989-2008

BACKGROUND

Drywall installers are at high risk for work-related falls from height (FFH).

METHODS

We defined a 20-year (1989-2008) cohort of 5,073 union drywall carpenters in Washington State, their worker-hours, and FFH. FFH rate patterns were examined using Poisson regression.

RESULTS

Drywall installers' FFH rates declined over time and varied little by worker age and time in the union. However, among FFH involving drywall sheets, workers with <10 union years were at high risk. Narratives consistently described the surface from which workers fell, commonly scaffolds (33%), ladders (21%), and stilts (13%). Work task, height fallen, protective equipment use, work speed, weather, influence of other workers/workgroups, and tool/equipment specifics were not often reported.

PRACTICAL APPLICATIONS

In addition to continued efforts to prevent falls from scaffolds and ladders, efforts should address stilt use and less experienced workers who may have greater exposure. Consistency in reported narrative elements may improve FFH risk factor identification and prevention effort evaluation.

Twenty years of workers' compensation costs due to falls from height among union carpenters, Washington state

BACKGROUND

Falls from height (FFH) are a longstanding, serious problem in construction.

METHODS

We report workers' compensation (WC) payments associated with FFH among a cohort (n = 24,830; 1989-2008) of carpenters. Mean/median payments, cost rates, and adjusted rate ratios based on hours worked were calculated using negative-binomial regression.

RESULTS

Over the 20-year period FFH accounted for $66.6 million in WC payments or $700 per year for each full-time equivalent (2,000 hr of work). FFH were responsible for 5.5% of injuries but 15.1% of costs. Cost declines were observed, but not monotonically. Reductions were more pronounced for indemnity than medical care. Mean costs were 2.3 times greater among carpenters over 50 than those under 30; cost rates were only modestly higher.

CONCLUSIONS

Significant progress has been made in reducing WC payments associated with FFH in this cohort particularly through 1996; primary gains reflect reduction in frequency of falls. FFH that occur remain costly.

Previous employment histories and quality of life in older ages: sequence analyses using SHARELIFE

This article summarizes previous employment histories and studies associations between types of histories and quality of life in older ages. Retrospective information from the Survey of Health, Ageing and Retirement in Europe (SHARE) was used and the occupational situation for each age between 30 and 65 of 4,808 men and 4,907 women aged 65 or older in Europe was considered. Similar histories were regrouped using sequence analyses, and multi-level modelling was applied to study associations with quality of life. To avoid reverse causality, individuals with poor health prior to or during their working life were excluded. Men's employment histories were dominated by long periods of paid employment that ended in retirement (‘regular’ histories). Women's histories were more diverse and also involved domestic work, either preceding regular careers (‘mixed’ histories) or dominating working life (‘home-maker’ histories). The highest quality of life was found among women with mixed histories and among men with regular histories and late retirement. In contrast, retirement between 55 and 60 (but not earlier) and regular histories ending in unemployment or domestic work (for men only) were related to lower quality of life, as well as home-maker histories in the case of women. Findings remain significant after controlling for social position, partnership and parental history, as well as income in older ages. Results point to the importance of continuous employment for health and wellbeing, not only during the working life, but also after labour market exit.

Construction workers struggle with a high prevalence of mental distress, and this is associated with their pain and injuries

OBJECTIVES

We aimed to investigate how mental distress was associated with pain and injuries in a convenience sample of construction workers.

METHODS

A cross-sectional, mental health assessment was conducted in a convenience sample of construction workers (N = 172). A subsample participated in a clinical interview (n = 10). We used a cutoff (1.50 or greater) on Hopkins Symptom Checklist-25 to determine substantial mental distress and determined associations with pain and injury outcomes.

RESULTS

The prevalence of substantial mental distress was 16% in the workers. This was supported by follow-up clinical interviews where 9 of 10 workers fulfilled the criteria for a mental disorder. Substantial mental distress was associated with both injury rate and self-reported pain.

CONCLUSION

This pilot study strongly suggests the need for rigorous studies on construction worker mental health and how it affects their work and well-being.

Risk-based Analysis of Construction Accidents in Iran During 2007-2011-Meta Analyze Study

BACKGROUND

The present study aimed to investigate the characteristics of occupational accidents and frequency and severity of work related accidents in the construction industry among Iranian insured workers during the years 20072011.

METHODS

The Iranian Social Security Organization (ISSO) accident database containing 21,864 cases between the years 2007-2011 was applied in this study. In the next step, Total Accident Rate (TRA), Total Severity Index (TSI), and Risk Factor (RF) were defined. The core of this work is devoted to analyzing the data from different perspectives such as age of workers, occupation and construction phase, day of the week, time of the day, seasonal analysis, regional considerations, type of accident, and body parts affected.

RESULTS

Workers between 15-19 years old (TAR=13.4%) are almost six times more exposed to risk of accident than the average of all ages (TAR=2.51%). Laborers and structural workers (TAR=66.6%) and those working at heights (TAR=47.2%) experience more accidents than other groups of workers. Moreover, older workers over 65 years old (TSI=1.97%> average TSI=1.60%), work supervisors (TSI=12.20% >average TSI=9.09%), and night shift workers (TSI=1.89% >average TSI=1.47%) are more prone to severe accidents.

CONCLUSION

It is recommended that laborers, young workers, weekend and night shift workers be supervised more carefully in the workplace. Use of Personal Protective Equipment (PPE) should be compulsory in working environments, and special attention should be undertaken to people working outdoors and at heights. It is also suggested that policymakers pay more attention to the improvement of safety conditions in deprived and cold western regions.

How well are we controlling falls from height in construction? Experiences of union carpenters in Washington State, 1989-2008

BACKGROUND

Falls from height (FFH) continue to cause significant morbidity and mortality across the construction industry.

METHODS

By linking data on work hours with workers' compensation records, rates of work-related injuries resulting from FFH and associated days away from work were evaluated among a large cohort (n = 24,830) of union carpenters in Washington State from 1989 to 2008. Using Poisson regression we assessed rates of FFH over the 20-year period while adjusting for temporal trend in other work-related injuries. Patterns of paid lost days (PLDs) were assessed with negative binomial regression.

RESULTS

Crude rates of FFH decreased 82% over the 20-year period. Reductions were more modest and without demonstrable change since 1996 when adjusting for the temporal reduction in other injuries. Younger workers had higher injury rates; older workers lost more days following falls. Rates of PLDs associated with falls decreased over time, but there was not a consistent decline in mean lost days per fall.

CONCLUSION

These patterns are consistent with decreased FFH for several years surrounding state (1991) and then federal (1994) fall standards; the decline during this time period exceeded those seen in injury rates overall in this cohort. While crude rates of FFH have continued to decline, the decline is not as substantial as that seen for other types of injuries. This could reflect a variety of things including more global efforts designed to control risk (site planning, safety accountability) and changes in reporting practices.

Age in relation to worker compensation costs in the construction industry

BACKGROUND

A better understanding of how workers' compensation (WC) costs are affected by an aging US workforce is needed, especially for physically demanding industries, such as construction.

METHODS

The relationship between age and injury type on claim costs was evaluated using a database of 107,064 Colorado WC claims filed between 1998 and 2008 among construction workers.

RESULTS

Mean WC costs increased with increasing age for total cost (P < 0.0001), medical costs (P < 0.0001), and indemnity costs (P < 0.0001). For each one-year increase in age, indemnity, and medical costs increased by 3.5% and 1.1%, respectively. For specific injury types, such as strains and contusions, the association between age and indemnity costs was higher among claimants aged ≥65 compared to claimants aged 18-24.

CONCLUSIONS

Our findings suggest that specific injury types may be partially responsible for the higher indemnity costs among older construction workers, compared with their younger coworkers.