4. Quantitative definition of disasters

There are trials to define disasters on the quantitative basis. This has huge variations because disasters, as noticed in the previous definitions, depend on the balance between needs and resources. Depending on that, if there are low resources, then a disaster can occur in a lower scale. On the contrary, if there are many resources then it requires larger-scale events to create a disaster. In the USA, FEMA put the following quantitative descriptions for disaster depending on Lesley Sheehan & Kenneth Hewitt's work in 1969:

"A major disaster was defined as an incident that includes one of the following events:


If we look at the previous definitions by well-known organizations, we will find that they all agree about the serious effects on community and that community cannot respond to the incident depending on its own resources. The social explanation of the disaster encourages us to make changes in our social system and make improvement on the disaster outcome. Also, it confirms that there is no one definition for disaster.
