Investigation and Development of Energy Concept for Assessing Impacts to Worker Safety and Work Quality

Abstract

Many duties and tasks may be physically and mentally demanding for construction workers. The performance of construction workers is critical to a project's success and impacted by various internal and external factors, conditions, resources, and activities. Previous studies have shown that construction worker perceptions of the conditions present on a construction site and task characteristics can influence their mental workload and performance with respect to safety and work quality. However, limited tools are available to construction practitioners to assess and quantify mental workload in order to improve safety and quality based on critical task-level factors. Further research is required to determine how a construction site's environment, operations, and work tasks impact the safety of construction workers and the quality of work due to the mental workload (MWL) that workers experience while performing tasks. The overarching goal of this research is to explore and develop a new method of quantifying and assessing the level of worker MWL using the energy concept to evaluate and predict worker safety and work quality on construction sites. The concept of energy is used as a means to quantify MWL. To achieve the research goal, a conceptual model from previous studies was used as a starting point. Three levels of task characteristics (constituents, components, and metrics) comprised the conceptual model used to measure worker MWL during construction activities. The present study utilized a multi-method approach consisting of insights from construction professionals, perspectives of construction workers, field observations, and a controlled experiment to clarify, identify, and quantify constituents, components, and metrics and confirm the developed tool. Through the incorporation of the constituents, components, and metrics into an assessment process to evaluate MWL using the energy concept, the Assessment Approach of Mental Workload Task Index (MWL-TX) was developed and applied on an actual construction site. The present research contributes to the body of knowledge and benefits the construction industry by enhancing understanding of the connection between task characteristics and work components, and creating an objective method for MWL quantification and evaluation. The current research also contributes to practice by providing a tool that construction practitioners can use to determine the extent to which task-related worker MWL is a concern during work operations and whether there is a potential impact of the MWL on worker safety and work quality.