Assessing Safety Risk among Different Construction Trades: Quantitative Approach

The construction industry has one of the worst occupational health and safety records of all industries. In recognition of this, several innovative safety techniques have been introduced to mitigate undesired events before they occur, including safety risk assessment. However, evaluation of safety risk is challenging due to the dynamic nature of the construction work environment and lack of reliable references. This study (1) compares safety risk of different construction trades in terms of common hazard types and sources of injuries, and (2) proposes safety risk quantification models by occupations, which can play a role as a safety reference for reliable safety risk assessment. Using occupational injury data, two relative injury indexes, relative fatality and relative days away injury indexes, were used to compare relative safety among 19 different construction occupations as well as the construction average. Each relative injury index of an occupation was further decomposed into hazard types, sources of injury, and injury scenarios. Based on comparative relative injury index data, a tree-based safety risk quantification model was proposed. The findings indicate each occupation has a unique pattern of safety data structure in terms of hazards and sources of injuries. In addition, the same occupation had different hazard types and sources of injury that can lead to different injury severities. A construction project typically involves numerous workers and resources. The safety risk analysis presented in this paper can be used as a general safety reference by safety managers to understand the dynamic nature of safety risk. It can also aid in preparing safety actions, such as inspections or training, more effectively by focusing on high-risk occupations, hazard types, or sources of injury.