The evaluation and improvement of safety behaviors among contractors of a large steel manufacturing company by fuzzy data envelopment analysis

摘要

The objective of the present research is to rank the contractor companies of one of the Iranian steel manufacturing companies considering their safety behavior and also to determine the best combination of contractor companies. After sampling the staff's safety behavior and a determination of the number of safe and unsafe acts in each company, a relation between experience, educational level and staff age with safety behaviors was observed (p < 0.05). Because of this relation, experience, age and educational level were chosen as the inputs and safety behavior as the output of fuzzy data envelopment analysis (FDEA). By considering three inputs and one output, 640 distinct models (using α-cut) were solved by FDEA. After calculating the upper and lower bound of efficiency (α = 0, 0.25, 0.5, 0.75, 1) for each decision making unit (DMU), the fuzzy efficiency numbers were ranked by the Chen & Klein method. Companies number 64 and 1 had respectively the best and worst ranks. The rankings obtained by FDEA were compared and verified with rankings done using DEA. This is the first study that uses FDEA for assessment and optimization of contractor companies in an uncertain and complex environment. The modeling approach of this study may be used for other complex systems with ambiguous data.