Uncertainty in safety : new techniques for the assessment and optimisation of safety in process industry

At this moment there is no standardised method for the assessment for safety in the process industry. Many companies and institutes use qualitative techniques for safety analysis while other companies and institutes use quantitative techniques. The authors of this paper will compare different quantitative and qualitative techniques and will show that different analysis techniques show widely different results. It will also be shown that the qualitative techniques are highly dependent on human judgment while the quantitative techniques suffer from highly uncertain underlying data. In the second part of the paper a new quantitative technique will be presented that can be used for the assessment of safety in the process industry. This technique is not only able to take into account uncertain data but the user can also identify parameters that influence safety dominantly. Finally the paper presents an example of the new technique applied to a practical system used in Dutch petrochemical industr