Abstract
Subcontractors play a critical role in construction projects. Yet their workers are often exposed to high occupational health and safety (OHS) risks. Although subcontractors hold formal employer responsibility, OHS outcomes are strongly influenced by how main contractors and clients organize and manage project execution. This paper examines how subcontractors can be effectively involved in OHS management and how their safety can be ensured in construction projects. The study is based on case studies of three large construction projects in Norway, involving three clients, three principal contractors and nine subcontractors. The findings show that ensuring subcontractor worker safety requires a combination of formal structures, such as procurement and contractual requirements, and relational practices, including dialogue, leadership presence, and involvement in planning and risk management. Integrating OHS with production and quality management is identified as a key factor in managing risk for subcontractor workers under time pressure.