Why ordinary hazard identification sessions commonly fail to reduce the amount of inconclusive knowledge about electrostatic hazards

All of us have experienced static electricity in one form or the other. In some cases, however, there is inconclusive knowledge about whether static electricity constitutes a hazard or merely a nuisance. In an industrial environment, the risk-based decision-making concerning static electricity is far from straight forward. Indeed, too often fires and explosions have occurred due to inconclusive knowledge about electrostatic hazards. As a result of the complexity of the phenomenon, static electricity is seldom considered in a comprehensive way when decisions on precautionary measures to tackle electrostatic problems are taken. Thus add-on safety solutions such as grounding or inerting are commonly used instead of inherently safer options. Based on the ideas of inherent safer processes and plant design, problems related to static electricity should be identified and removed at the earliest possible stage of process development. As not all electrostatic problems can be removed, a need to address these problems during the whole life cycle of a process remains, i.e. from the choice of the synthetic route to the decommissioning of the plant. The intention of this paper is to follow the process from process development via plant design to plant operation in order to find out what opportunities there are to identify potential electrostatic problems as part of ordinary risk analyses. The authors selected hazard identification methods that already are commonly used by the process industry in Finland. The following risk analysis methods were used to assess the possibility to identify electrostatic hazards at different stages of the life cycle: * Potential Problem Analysis * Hazardous Scenario Analysis (HAZSCAN) * A method for the classification of areas where explosive atmospheres may occur * Hazard and Operability Study (HAZOP) * Action Error Analysis. The results presented are mainly from desktop studies, where the analysis group consisted of experts in risk analysis techniques, static electricity and process engineering. The results show that it, in principle, is possible to identify electrostatic problems during general hazard identification sessions. This seems to require, however, that the phenomena involved are well known by one or several persons in the analysis team. Inconclusive information also about the chemicals, the process, and the construction materials makes the work of the analysis team even more difficult. In order for the analysis sessions to be both successful and cost efficient, there seems to be a special need for the analysis leader to understand not only process technology and the risk analysis method used, but also enough about electrostatics to understand where in the process or plant design static electricity might cause problems and where it can be overlooked. Some of the experiences of the studies described in this paper will be used in the development of a new method for the identification of electrostatic hazards and potential operational problems in a process environment. The paper therefore also presents some ideas that have been used as starting points for the development of this method. Moreover, it discusses some hurdles that need to be overcome in order for such a risk analysis method to be generally accepted by industry.