A Study on Predicting the Occurrence Probability of Safety Accidents of Major Work Type in Construction Work
Authors:   Form of Public Safety and Culture, Lee Jong Sik 
Published: June 2022

In a construction site with high uncertainty and a lot of risks, a management supervisor can reduce safety accidents by recognizing and removing hazards in advance. Therefore, the prevention possibility of safety accidents may vary depending on the judgment of the management supervisor as follows. 1) If the management supervisor judges that there are no accident possibility because the management supervisor is not aware of the risk. 2) If the management supervisor judges that there are no hazards and there are no accident possibility. 3) If the management supervisor recognizes the hazards and judges that there are accident possibility. This study presented a prediction model of occurrence probability of safety accident using the probability that the management supervisor will make an appropriate judgment about the presence or absence of a risk and the probability that the management supervisor will make an improper judgment as variables. This study defined the causal relationship for the causes and results of safety accidents at construction sites using a fault tree analysis and structured using a Bayesian network. In addition, a basic model for predicting the occurrence probability of safety accident at construction sites was presented using Bayes' theorem, an inductive approach and applied to virtual formwork to examine the consistency of the study model through case studies. As a result of the case study, it was confirmed that the occurrence probability of safety accident in the formwork changed according to the change in the probability of determining that there are hazards but the management supervisor does not recognize them and judges that there are no accident possibility and the change of the probability that the management supervisor recognizes hazards and judges that there are accident possibility. In addition, when the probability of appropriate judgment that there are accident possibility by recognizing hazards decreased by 10%, the occurrence probability of safety accidents decreased by more than 10%. This phenomenon was the same in all types of safety accidents. On the other hand, when there were hazards but the probability of inappropriate judgment that there were no accident possibility increased by 10%, the increase rate of the occurrence probability of safety accident was more than 10%. Through this study, it was confirmed that the occurrence probability of safety accident was updated depending on whether the management supervisor was aware of the safety accident in advance. When the management supervisor did not recognize the hazards, the occurrence probability of safety accident increased. And, the increase range in the occurrence probability of a safety accident was larger than the increase range in the probability of unawareness of the hazards. Therefore, in order to prevent safety accidents at construction sites, it is judged that it is necessary to strengthen the pre-management activities to recognize and remove the hazards inherent in the work through the safety review of the design.