It is well-known that the construction industry has a higher risk of deaths than other industries. The higher risk in this industry could be attributable to the combination of the followings: 1) outdoor work site; 2) the nature of employment; 3) complex construction contracts; and 4) various method of construction technology. In the case of construction work, the number of construction work types can range from dozens to hundreds. Consequently, the degree of risk to the construction method can not be evaluated only as the size of the accident and the number of accident like other industries. On this basis, it is necessary to analyze and evaluate potential work-related risk factors as well as the portion of work intensity for each type of work to determine the degree of risk. The goal of this study was to measure the risk of various construction works by taking into consideration the number of working staffs in the actual field of construction and the working time of each type of construction work. Also, the analytic hierarchy process throughout expert interviews was employed if there is no past data, or the amount of data is insufficient.
As a result of analysis of deaths by construction type, the number of deaths was the largest in three construction types including the formwork, temporary construction, and steel frame construction. Among three construction types, the formwork showed a significantly higher rate of deaths in past as compared to the others, but recently the temporary construction work showed a biggest death rate.
As a result of analysis of accident by construction type, the temporary construction work recorded the highest injuries (2,090 cases), followed by the dismantling construction (1,215 cases), formworks (1,174 cases) and moving not related with works (1,122 cases). The result suggested that the temporary construction work is most dangerous construction work type in both the death rate and accident rate.
As a result of analyzing the mortality risk in consideration of the duration of work and number of workers by each type of work, the highest risk of death was found in the steel frame construction, unlike the occurrence ranking in the number of deaths, followed by the temporary construction work, the concrete work, the waterproofing work and the painting work.
As a result of analyzing the general accident risk in consideration of the duration of work and number of workers by each type of work, the steel frame construction, temporary construction, foundation & earthworks, facility construction, and concrete construction were found to be risky.
According to the AHP results, steel frame construction, foundation construction, foundation and earthworks, facility construction and concrete construction were analyzed as high risk type. Based on the accident statistics, the results of the risk assessment considering the annual workforce input showed higher risk in steel construction, foundation construction, concrete construction, demolition construction and painting construction.
Finally, in order to verify the risk estimates by construction type, we compared the risk ranking by type of work considering the annual workforce input. A correlation analysis was conducted between the risk ranking by type of work and the risk ranking by AHP analysis. According to the analysis results, the risk rankings by construction type of construction work were significantly correlated with the risk ranking by AHP analysis. Therefore, in order to evaluate the risk of the work by the new method without accident cases or statistical data, it is considered that the risk of the work and the work type can be estimated by using the AHP analysis by the expert evaluation.
In this study, we conducted a study on the risk of general accident unlike the other studies that have been carried out so far. The results of the AHP analysis can be used as the basic data for determining the priority of safety management in the future. In order to prevent serious accidents including death, the general accident and near misses should be considered for proactive safety management instead of reactive nature of the current safety management trend focusing on the severe accident.