Quantitative Risk Assessment For Industrial Safety

Abstract

Risk assessment (RA) is a means of making a systematic analysis of the risks from hazardous activities, and forming a rational evaluation of their significance, in order to provide input to a decision-making process. RA is sometimes called ‘probabilistic risk assessment’ or ‘probabilistic safety analysis’; terms originally used in the nuclear industry. The term ‘quantified risk assessment’ is synonymous with QRA as used here. The term ‘quantitative risk analysis’ is widely used, but strictly this refers to the purely numerical analysis of risks without any evaluation of their significance [5]. RA is probably the most sophisticated technique available to engineers to predict the risks of accidents and give guidance on appropriate means of minimising them. Nevertheless, while it uses scientific methods and verifiable data, RA is a rather immature and highly judgemental technique, and its results have a large degree of uncertainty. Despite this, many branches of engineering have found that RA can give useful guidance. However, RA should not be the only input to decision-making about safety, as other techniques based on experience and judgement may be appropriate as well.