Complex system for risk assessment in ESD hazardous processes with unusually high risks

Abstract

Many types of granulated substances and liquids that are heavily used in industry may become easily inflammable when they are adequately mixed with air either in fine particle or vapour form. Many of these substances have very low conductivity which means that the particles can easily acquire electrostatic charge during transport or mixing operations, and the resulting electrostatic discharge may ignite the atmosphere leading to damage and even loss of life. The probabilities with which these events occur are hard to quantify. The authors present a case study and estimate the probability of ignition using FFTA (fuzzy fault tree analysis.) The result of the calculations is affected by several parameters, such as process temperature and humidity, which using suitable instruments can be easily observed. The authors thus propose a new approach where these parameters can be continuously monitored, and the fault tree evaluated in real time and early warning of the danger can be provided.