Focal Depth 3 : Natural Disaster. "Vertical distance from the earth's surface to the place of origin (hypocenter, focus) of an earthquake". (UNDHA, Disaster Management Glossary, 1992, p. 41)
B. Wayne Blanchard, Guide To Emergency Management and Related Terms, Definitions, Concepts, Acronyms, Organizations, Programs, Guidance, Executive Orders & Legislation, A Tutorial on Emergency Management, Broadly Defined, Past and Present, B. Wayne Blanchard, USA 2007 (Last Modified 2008). http://training.fema.gov/EMIWeb/edu/docs/terms%20a nd%20definitions/Terms%20and%20Definitions.pdf, (Emr Mgt/ ND and Other Dzstr - Amer) {11}