Saving life and reducing economic disruption

The worst effects of any disaster are the deaths and injuries caused. The scale of disasters and the number of people they kill are the primary justifications for mitigation. Understanding the way that people are killed and injured in disasters is a prerequisite for reducing casualties. Among the sudden onset disasters, floods and earthquakes cause the most casualties worldwide, with storms and high winds being less deadly but far more widespread.

In earthquakes over 75% of fatalities are caused by building collapse. In floods deaths occur by drowning, mainly outdoors and in fast flowing currents or in turbulent water. Saving lives in earthquakes means focussing on prevention of building collapse. Reducing fatalities from floods means limiting the exposure of people to rapid inundation - either by keeping people out of the track of potential water flows or by preventing the flows from occurring.

The consequences of physical damage are often more important than the damage itself. A damaged factory can no longer continue to manufacture. The company may not survive the loss. The people it employs may lose their jobs. The jobless have no income to spend in their local shops and the whole local economy suffers. Damage to infrastructure and to the means of production depresses the economy.

Mitigation also entails the protection of the economy from disasters. Economic activity in the more industrialized societies is complex and interdependent, with service industries dependent on manufacturing, which in turn relies on supplies of raw materials, labor, power and communications. This complex interdependency is extremely vulnerable to disruption by hazards affecting any one link in the chain. Newly industrializing societies are most vulnerable of all.

Agricultural sectors of the economy are most vulnerable to drought but also to floods and high winds, disease and pest attack and pollution. Industry is more vulnerable to earthquake damage and the disruption of transportation and utilities networks. Commerce and finance are most vulnerable to disruption of production, population migration and to breakdowns in communications systems. Mitigation measures that focus on protecting the most vulnerable elements and activities - the weakest links - in the different sectors of the economy will help protect the achievements of economic development.