Introduction: Industrial progress, development plans, and infrastructure projects, despite all the benefits and benefits that human beings have had, have been a source of fatalities, risks, and significant failures. Risk Assessment an organized and systematic approach to hazard identification and risk assessment for ranking decisions in order to reduce risk is partially acceptable. The purpose of this study was to identify the hazards in the Ilam gas refinery using   William Fein method which is a quantitative method.
 
Material & Methods: This descriptive-analytic epidemiologic study was conducted in Ilam gas refinery in 2012. The sample consisted of 9 units from 18 units of Ilam gas refinery which were randomly selected. In order to identify the risks, a team of representatives from the departments and departments of the present project conducted the projrect. In this document, the HSE-FO-001 (0) -90 hazard identification and risk assessment was also documented in units. This method evaluates and calculates the risks using the severity of the outcome, the probability of occurrence, and the exposure level.
 
Findings: In this study, 289 risks were identified, of which 5 (0.73%) risks at emergency level (urgent need for corrective actions), 40 risks (13.84%) at abnormal level (requiring consideration and attention Faster) and 244 risks (84.43%) at the level of natural risk (to be eliminated).
 
Discussion & Conclusions: The major dangers that threaten employees at the Ilam gas refinery are the risks of work at height and inhalation of sour gas containing hydrogen sulfide. Therefore, it is better to apply engineering measures in different units of the refinery  to reduce the level of risk.