None of the existing methods of evaluating loss or saving life, or assessing an increase or reduction in accidents resulting from investment projects, is satisfactory for a number of reasons. This is so chiefly because they are all inconsistent with the Pareto base of existing allocation theory and benefit-cost analysis. Strict application of the Pareto principle to changes in accidents and fatalities involves a calculation of the compensating variation associated with the changes in risk bearing regarded as external effects. Several of these external effects are discussed at length.