טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentAizenchtadt Elena
SubjectLessons from Radiological Accidents to Reduce Risk and
Enhance Safety
DepartmentDepartment of Quality Assurance and Reliability
Supervisor Dr. Phineas Dickstein


Abstract

The goal of this work is to accumulate the existing data regarding radiological and criticality accidents and analyze the events according to their cause, to examine the evolution of the accidents' causes with time, to assess quantitatively the a-posteriori risk, and to develop an a-posteriori measure of radiological risk realization.

The survey refers to some major areas of practice: radiography, radiation facilities, radiotherapy and the nuclear-fuel related industry. This survey includes neither X-ray machines or reported nuclear weapon accidents.

The events are classified as originating either as a consequence of a technical problem or as a cause that has to do with the human factor. Those events related to the human factor are further classified and featured as human errors, negligence and unlawful conducts. Following a concise screening and tabulation of all the events, this work details the relative contributions of each of the features of the human factor to the occurrence of the event and the evolution of the relative attributions with the years.

Apparently, a retrospective investigation shows that the a-posteriori risks of radiological and criticality accidents are similar. However, the criticality related risk has been in the decline as of 1960, while the a-posteriori risk of radiological related activities has been constantly on the rise. Breaking into parts the contributions to the a-posteriori radiological activities, it comes out that the risks of radiotherapy, radiography industrial irradiation are similar.

A new feature was presented in this work, namely: “Risk Realization Factor”. This feature may provide a mean to evaluate a-posteriori the actual against the potential risks of accidents that took place.