SUMMARY

APPRAISING DISASTER MITIGATION OPTIONS

One of the main uses of risk analysis is to assist in choosing between different mitigation options, all of which may be costly to apply, though beneficial in the longer term.

Cost benefit analysis may be used to compare different strategies if the costs are the extra costs of introducing mitigation measures while the benefits are the reductions in expected losses expressed financially. Either a minimum cost or a maximum benefit/cost ratio criterion may be used as a criterion of choice. One difficulty is the evaluation of the benefit from saving a human life in financial terms

Alternatively an acceptable risk may be defined in relation to other risks to individuals or society, the balanced risk criterion. This method ignores the cost element.

A more sophisticated approach is to quantify the costs and different types of benefits separately (economic, human), and also calculate the cost effectiveness of each strategy in relation to different objectives of mitigation. The approach is more in keeping with the social and economic realities of decsion-making.

In any mitigation strategy the costs and the benefits will be unevenly distributed within society. There may be some losers. It can help to quantify the costs and benefits to different individuals, but ultimately choosing an appropriate strategy is a political rather than a technical matter.