In deciding whether or not to introduce a safety measure a quantitative approach generally requires the decision maker to consider its financial cost, as well as its benefits in terms of saving of lives. To determine whether the measure is worth introducing a financial value is commonly placed on preventing a fatality (VPF - the value of preventing a fatality). Such a VPF is said not be the price society puts on a life, but rather the aggregated value of reducing a small probability of death for a very large number of people. This raises a number of questions. First, are the 'willingness to pay' methods used to determine this figure consistent with such an understanding? Second, is there any reason to think that the VPF should be a constant for a single person for different types or magnitudes of risk, or for different people over the same risk? Third, does current terminology stand in the way of a proper appreciation of the issues, and can this be improved?Article