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All people take risk, some of which could be avoided at the expense of either time or money. When we spend money to reduce risk, we are, whether we like it or not, implicitly making a trade‐off between the cost of the risk reduction measure and a benefit (i.e. a reduced probability of death). The ratio of the cost we are willing to accept in exchange for a small change in the probability of a fatality is expressed in units of “dollars per death,” or the monetary value of a fatality (Ashenfelter 2005).

The term statistical life is used not only because the cost–benefit evaluation concerns the probability of saving a life but also because we want to consider the life of a “general” person, that is, a person chosen at random from a population. This is because for most people, the value of life is quite different depending on whose life we consider. Generally, the value of our own life and the lives of our family are considerably higher than the value of the life of someone we do not know.

Consider a decision‐maker who has to decide whether to implement a specified risk reduction measure that will increase the cost of an investment by . A risk analysis shows that this measure will reduce the probability of a fatality by . If the decision‐maker evaluates and decides which she is willing to invest in order to obtain the reduction , the cost–benefit factor can be used to derive her value of a statistical life (VSL). VSL is obviously not a constant but is dependent on the context in the same way as acceptable risk. Factors that can influence VSL are the probability of a fatality, the total value of the investment, the consequences of a fatality for the company's reputation, and so on.

There has been considerable research into the VSL, and different VSL values have been used in specific studies. The VSL values typically range from 1 to 15 million USD in different countries and different industries.

Observe that the VSL is not a “value (or price) of life” in the sense of a sum that any given individual would accept in compensation for the certainty of his or her own death. Rather, it is derived from studies of what a company or the public would be willing to pay for a reduction in already low levels of residual risk. VSL is hence a measure of a company's or society's values.