Case study of safe working conditions in spanish merchant shipsObjectiveThis paper aims to show a practical case study of safety assessment concerning possible injuries and fire occurring in the engine room on-board a merchant ship, due to fatigue.MethodsThe methodology was centred in literature hazard identification, measurements in real ships and heat stress indices definition.ResultsSome corrections are proposed in order to obtain a safe environment for workers in the engine control room and to prevent fatigue risks at the engine room. This will allow adequate oil leakage detection and, as a consequence, improve fire prevention.DiscussionTraining is a preventive control option, but this study allows the understanding of new corrective control options like design corrections.