Construction Safety Risks Assessment in a Turbine Hall Unit of a Power Plant Based on a Bow-Tie Technique

Major construction projects have always been at high risk, and the projects’ safety is vulnerable to damages. Therefore, safety risks assessment is one of the important activities to prioritize existing risks and manage risks in the construction of the power plants as one of the most dangerous industries. This study aimed to assess the safety risks in the construction of power plants based on a Bow-tie technique.

This cross-sectional analytical study was carried out in a turbin hall unit of a combined cycle power plant under construction in 2017. In this study, safety risks assessment was performed based on the Bow-tie technique using Bow Tie ProTM software. In order to enhance the efficiency of this study, two phases, including a system description, and hazard identification have been designed and implemented before the safety risks assessment.

The relationship between activities and threats followed by the consequences of each of the identified hazards showed that the biggest threats were due to cylinders under pressure as well as welding and cutting activities. In addition, they included 8 threats, such as mechanical damage, heat, transportation, unsafe connections, storage of the cylinders, oil and grease, leakage, and flame retardation. It should be noted that the majority of consequences were associated with loading and heavy load lifting (including 3 consequences, such as human injury as well as crane and equipment failure), cylinders under pressure, as well as welding and cutting activities (including 3 consequences, such as human injury, fire and explosion, and equipment failure).

Based on the obtained results, the Bow Tie ProTM software is a suitable method to assess the safety risks in power plant construction. In addition, the risk assessment of the turbine hall units can be considered to prevent threats and reduce the consequences of accidents.