Risk assessment of probable human errors in the scaffold erection and dismantling procedure: a fuzzy approach.

Objectives. Despite widespread use of scaffolds on construction sites, they are the most common causes of accidents, injuries and fatalities in this sector. About 80-90% of all occupational accidents occur as a result of human factors. On construction sites, proper erection/dismantling of scaffold is possibly the most essential factor in preventing accidents as it is one of the factors reported to be highly statistically significant in correlation to a high overall scaffold safety rating. Therefore, analysis of human errors (HEs) caused by scaffolders is important to be implemented. The main objective of this study was to evaluate possible HEs during scaffold erection and dismantling (SE&D). Methods. Stages involved were identified using hierarchical task analysis (HTA). Risk values of HEs were then evaluated using the fuzzy analytical hierarchy process (FAHP). Results. Our findings indicate that the highest and lowest risk values were related to the errors of 'failure to reattach braces and connections prior to dismantling scaffolds' and 'insufficient preparation of the firm foundation', respectively. Conclusion. This study formulates a method to estimate the risk of potential HEs in SE&D.