Abstract
The authors investigated the influence which the metropolitan wide area power failure generated on August 14, 2006 had on the information system of various business units and disaster prevention agencies, and analyzed the influence on the vulnerability of an existing information system and recovery capacity of a business unit to the sudden power failure in case of an earthquake. Since the power failure was fortunately generated at the early morning in the Bon holiday period and it recovered within about 1 hour, material and human damage was small. However there were some typical influences which should be carefully investigated about the information system.
