1.2 Definition of Event

Based on the knowledge gained from various sources and documentation, a common definition for a disaster has been defined for this study, which entails the following:

• Suddenness – Unforeseen, unpredictable

• Scale – Has large impact and involves a large part of the public

• Institutional Response – Beyond the normal capacity for coping and involving many institutions

• Prolonged Duration of Effect – Impact does not quickly dissipate

• Uncertainty in Behavioral Response – Outside of normal range of experience.

June 26, 2006
Publication #FHWA-HOP-08-020