Review and Discussion of Types of Risks in View of Different Risk Perspectives.

In the scientific and popular literature, different types of risk are referred to, including uncertain risk, calculable risk, unseen risk, and unknown risk. The meaning of these terms is not always clear. For example, is not risk per definition always uncertain? Events can be unknown, but can risks be unknown? The present article reviews and discusses common types of risk in view of different risk perspectives. The understanding of the various types of risk depends on these perspectives. As an illustration, think about the difference in interpretations between a perspective in which risk is considered an event compared to one in which uncertainty is a main component of risk. In the former case, it makes sense to talk about an uncertain risk, but, in the latter case, the meaning is not straightforward and needs further clarifications. Through this review and discussion, the article aims to obtain new generic risk science knowledge on basic risk science concepts. Examples are provided, showing how this knowledge can be used to guide and improve the understanding and communication of risk in practice.