Traditional human reliability assessment techniques and accounting system cannot directly provide loss information for assessing the impacts of human errors. This obstacles force industrial managers to justify the proper accident and injury prevention process through their experiences. The efficiency and effectiveness of the system safety barriers are in doubt and the smooth operation of manufacturing activities are insecure. In this study, a human error cost estimation model is introduced to facilitate line managers with a proper tool to collect and calculate the total losses of its impact. Experts' judgments and pair wise comparison technique are incorporated to interrogate managers' knowledge of human errors and correspondent costs. This approach can overcome the problem of insufficient cost information caused by current accounting system and compensate the influence of safety and health department due to the low organizational status in quo. Although the cost figures may not represent exact amount of losses, the percentage of each cost factor in terms of department operation budget gives the managers a practical way for justifying how the resources should be allocated.