A system dynamics view of a behavior-based safety program in the construction industry

Behavior-based safety (BBS) has received significant attention in the construction industry during the past decades. Ample evidence suggests that BBS is an effective accident prevention strategy. Past BBS literature is dominated by successful case studies, while unsuccessful cases and cases with mixed effectiveness in reducing unsafe behavior are limited. This paper reports a BBS program designed and implemented in the Singapore construction industry. The BBS program was aimed at reducing unsafe behavior in nine categories: lifting operations, excavation, working at height, work platform & access, manual handling, hot work (welding/gas cutting), plant & equipment, traffic management, and personal protective equipment (PPE). It consists of traditional BBS elements such as baseline observations, feedback, goal setting, and interventions. In contrast to other successful applications, the BBS program produced mixed results of safety behavior over 36 weeks. This paper adopts a system dynamics view to explain the mixed effectiveness. Causal loop diagrams were developed to capture behavior change mechanisms underpinned by reinforcement theory and goal setting theory, as well as dynamic effects of contextual and cognitive factors. It is concluded that the mixed effectiveness can be attributed to three main issues: dynamics of goal commitment, punishment, and monetary incentive. This paper adds to the body of knowledge of behavior safety program in terms of theoretical basis and implementation. By reviewing the BBS program holistically and reflecting upon the details of the case study, this paper offers lessons and reference for future design and implementation of BBS program in the construction industry.