| In the context of risk assessment, the concept of '''risk''' can be viewed as the product of the '''likelihood''' of an event occurring and the '''consequences''' of that event (which may be biological, economic or environmental consequences). Additionally, the '''perception''' of the event is an important consideration, which can have a large impact upon risk. One example of a hazard which is generally ''perceived'' to be risky is radiation from nuclear power plants, due to a number of characteristics such as invisibility, association with long-term human health risks (including cancers), not viewed as being necessary, and being created from a process which many people do not understand. Therefore, when deciding where to site a nuclear power plant, consideration of the risk should include the likelihood of radiation release (which will generally be very low/negligible), the consequences of this (which are very high) '''and''' the perception of the risk by people who would live near to the power station.<br> | | In the context of risk assessment, the concept of '''risk''' can be viewed as the product of the '''likelihood''' of an event occurring and the '''consequences''' of that event (which may be biological, economic or environmental consequences). Additionally, the '''perception''' of the event is an important consideration, which can have a large impact upon risk. One example of a hazard which is generally ''perceived'' to be risky is radiation from nuclear power plants, due to a number of characteristics such as invisibility, association with long-term human health risks (including cancers), not viewed as being necessary, and being created from a process which many people do not understand. Therefore, when deciding where to site a nuclear power plant, consideration of the risk should include the likelihood of radiation release (which will generally be very low/negligible), the consequences of this (which are very high) '''and''' the perception of the risk by people who would live near to the power station.<br> |
| + | There are two main approaches to risk assessment, known as '''qualitative''' and ''''quantitative''' risk assessment. Qualitative risk assessment is a subjective process which denotes risk using words, and is commonly used in the early stages of a risk assessment, before comprehensive data have been collected. Quantitative risk assessment is also a predominantly subjective process, but the risk is denoted using probabilities (either as point estimates or as probability distributions). The results of a quantitative risk assessment are often more easy to convey to stakeholders, but care must be taken to not give the illusion of perfect knowledge when these are presented. In the case of both qualitative and quantitative risk assessment, the framework adopted should be clearly explained, all data sources should be appropriately referenced and the whole process should be transparent. |