Background: Considering that the frequency of a factor contribution to accidents occurrence is not always a reason for the importance of that factor, in addition to studying the participation of basic risk factors (BRFs) in the occurrence of the accidents, their importance must be investigated.
Objective: The purpose of the present study is to propose a quantitative methodology for monitoring BRFs based on Tripod Beta and Tripod Delta methods.
Methods: In the present study, first, the accidents that took place in the manufacturing companies were analyzed using a reactive approach, ie Tripod Beta. In the second step, a proactive, ie Tripod Delta was used to identify the weaknesses in the companies using safety performance indicators. Finally, a quantitative methodology for monitoring BRFs was proposed.
Results: According to the results of the accident analysis, training with 33 cases, hardware with 30 cases, procedures with 25 cases and error induce conditions with 14 cases were the most frequent contributing basic risk factors to the accidents. The lowest score of the basic risk factor indicators was related to the organization (4.9), design (8.8), training (8.3), procedures (8.3), and hardware (8.7). Based on the results, maintenance management, hardware, and training have the highest weight in the occurrence of accidents, 0.23, 0.179, and 0.125, respectively.
Conclusions: he proposed methodology helps the organization to continuously improve safety performance by identifying system's weaknesses before the accident and invest optimally in the system's critical points.
Keywords: Accident analysis; performance indicators; tripod beta; tripod delta.