Discrete Event Simulation as a Risk Analysis Tool for Remote A

Remote Afterloading Brachytherapy (RAB) is a cancer treatment process that uses ionizing radiation from radioactive materials to retard or destroy tumors. RAB uses a computer-controlled device to insert radioactive sources in or adjacent to the tissue to be exposed. Human errors and equipment failures in the RAB process can lead to the administration of incorrect radiation doses, the insertion of radioactive sources into the incorrect location in the body, or a treatment delivered to the wrong patient. Discrete Event Simulation (DES) is a technique for simulating and studying processes that can be described by a sequence of events that each have a distinct beginning and end. It is particularly well suited to modeling series of human tasks. This study used DES modeling to evaluate the potential for human errors in the process and responses made by humans to hardware and software failures. Using a task analysis of RAB combined with estimates of the probability of the errors that can occur in the RAB process, the events (previous tasks and errors) that lead to the errors, and information about potential equipment failures, a DES model of the process was developed. This project demonstrated that the DES model can be used to examine process safety through the identification of the human errors that are most likely to occur and the points in the process most vulnerable to severe consequences.