Hazard assessment as a tool for companies for managing accidental releases to the environment: Dissertation

An increasing desire and need of companies to be aware of their accidental releases to the environment was the main initiator of this study. Accidental releases are unexpected, random releases which can be caused by exceptional operative situations, technical failures or human errors. Hazard assessment does not assess major accidents only but also minor incidents, which result in a small spill. This thesis studied the management of hazard assessment of accidental releases and identified some relevant methods and how they could be used to optimize assessment of accidental releases to the environment. Further, the thesis produced an approach to hazard assessment which incorporates accidental releases into a product's life-cycle assessment. The study provided information which could be used as a base for general instructions for conducting the hazard assessment of accidental releases in companies. Different hazard assessment methods and approaches were studied in three case studies. In the first and second case study several traditional safety assessment methods used for the management of accidental releases and their effects on people were applied and extended to assess accidental releases to the environment. The first case study represented the wood industry and the second the chemical industry. In the third case study a hazard assessment approach was developed to assess accidental releases in a product's life-cycle assessment. The approach was illustrated with a product of the oil industry. Incompleteness in hazard identification and data uncertainty in hazard analysis may be the main sources for uncertainty in hazard assessment of accidental releases. In addition, system boundaries have a great impact on results as far as the hazard assessment of the whole life-cycle of a product is concerned. Problems are also encountered in the comparison of different kinds of environmental damages to each other. The results of this study demonstrated that despite uncertainties, hazard assessment of accidental releases is a flexible and useful tool for environmental management in companies. The preconditions for a succesful hazard assessment are the choice of a suitable method or methods, knowledge of the system under study, and a definition of the level of the assessment taking into account its goal and resources available.