Risk analysis of ammonia release in food refrigeration Using FTA technique and fuzzy logic

The purpose of this research is to analyze the risk of ammonia release in the cold storage of one of the large food companies in Mashhad. This is an applied research that was done using FTA technique and fuzzy logic. Fuzzy logic was used to weight experts' opinions (Delphi panel). In this study, to model the consequences and calculate the collective risk using the DNV PHAST 7.2 software, the most critical conditions that have the greatest possible contribution to the release of ammonia were, respectively: lack of proper and planned maintenance; Pressure increase and failure and defects in gaskets. Also, the results showed that the rate of death, toxicity and explosion is directly related to the distance. On the other hand, the maximum amount of possible losses in the event of an explosion will be in the winter season and at a distance of 14.26 meters, and finally, 95% of the losses due to the blast wave will occur at a distance of 13.54 meters and 99% of deaths of people up to a radius of 38.89 meters, also 50% of the deaths of people from the radius of 38.89 meters to the radius of 124.93 meters, and 10% of the deaths of people from the radius of 124.93 meters to the radius of 178.53 meters, also 1 percent of deaths from the radius of 178.53 meters to the radius of 234.05 meters.