Employee engagement, boredom and frontline construction workers feeling safe in their workplace.

•Examines the internal relations within the site-project organizational system (individuals, supervisors, and crews).•Providing insights into factors that impact a construction worker tacit and explicit safety at work.•Identifying the drivers of boredom coping, and their link to engagement.•Highlighting the role of the site supervisor in responding to safety breaches as a quality upgrade opportunity.