Assessment Techniques: General Terminology: LOSS PREVENTION is a general term used to describe a range of activities carried out in order to minimise any form of accidental loss, such as damage to people, property or the environment or purely financial loss due to plant outage. It includes the various techniques and approaches that have been developed for the assessment and control of risk. Some terms are used to describe the general objective of an activity, others are more specific and imply use of a particular technique. The extent and detail of an assessment depends on the particular problem, but the main stages are: (a) Identification of undesired events. (b) Analysis of the mechanisms by which undesired events could occur. (c) Consideration of the extent of any harmful effects. (d) Consideration of the likelihood of the undesired events and the likelihood of specific detrimental outcomes. Likelihood may be expressed as probability or frequency. (e) Judgements about the significance of the identified hazards and estimated risks. (f) Making and implementing decisions on courses of action, including ways of reducing the likelihood or consequences of undesired events. Various combinations of terms such as hazard, risk and safety with analysis, assessment and evaluation are in use to describe all or part of these activities, often loosely being used as synonyms. The term Hazard Analysis has become established and is now widely used to describe the systematic approach to hazard identification of stages (a) and (b) above followed by, where the severity of the hazards concerned justify it, the subsequent consideration of likelihood and consequences involved in stages (c) and (d). This consideration usually involves quantitative estimation to a greater or lesser degree. Where it does, that part of the process is sometimes referred to as risk analysis. Use of the term risk necessarily implies consideration of the likelihood of events and outcomes and, to this extent; the Working Party considers the term Probabilistic Risk Analysis to be tautologous. An advantage of using the terms hazard or safety to describe such studies is that discriminating can be made between publications on diverse subject matters, such as financial decision making and chemical plant safety, which give different meanings to the term risk. The Royal Society Study Group use the term risk estimation for stages (a) to (d), risk evaluation for stage (e) and risk management for stage (f), giving a general definition for the term Risk Assessment which covers stages (a) to (e) in this context. These terms do not encompass the very common situation where none or only some of the aspects are treated quantitatively and therefore the risk is not explicitly estimated. Because there are a number of factors, which influence the degree to, which the consideration of likelihood and consequences merit, or allow, quantitative estimation, the Working Party have found it useful to draw only a limited distinction between hazard analysis and risk analysis. The definition adopted for hazard analysis includes the identification stages (a) and (b) and the subsequent stages (c) and (d) so far as they are relevant in a particular case. It is recommended that the term risk should only be used, in describing a study or assessment, where an estimate of likelihood is involved. The use of the terrm assessment rather than analysis implies taking judgements about significance rather than analysis implies taking judgements about significance rather than estimation alone and so a definition for risk assessment covering stages (a) to (e) has been adopted. The term Hazard Survey is used to describe the application of loss prevention techniques in the assessment of the hazards from an installation and the means of controlling them. The scope of a hazard survey depends on the hazards and other features of the particular installation. It necessarily involves a consideration of possible accidents, and may include a risk assessment. It includes consideration of all features important to safety, i.e. design, management, operation, maintenance, protective equipment, emergency procedures and training. By identification and examination of the critical features, it should consider whether any justifiable improvements to reduce risk can be introduced. However, even when this whole process is complete, it is very rare that the risk can be reduced to zero. The remaining element of assessed risk is known as the Residual Risk and it is usually this, which is compared with the chosen criteria. The presentation of a justification for the safety of an installation, based for example on a hazard survey, is known as a Safety Case. This term is used in connection with the Control of Industrial Major Accident Hazards Regulations and will therefore have a quasi-legal use for the particular type of installation concerned. Similarly, safety evaluation is used to describe the analysis of risk required by the Pipelines Inspectorate. It is important to ensure that the standard of all features vital to safety are monitored and updated. The Safety Audit is a review process carried out with this objective. Features of the process and design, management policy and attitudes, training, operating procedures, emergency plans, personnel protection, accident reporting and so on, may be examined by appropriately qualified personnel, usually including safety professionals independent of production management, to disclose strengths and weaknesses and recommend necessary actions.