"The RDD is a device or mechanism that spreads radioactive material over an area with intent to cause harm, from the detonation of conventional explosives or other means. It is very difficult to construct an RDD that would deliver radiation doses high enough to cause immediate health effects or fatalities in a large number of people. However, if these materials are stolen or otherwise acquired, whether in the US or abroad, they could be used in an RDD to contaminate facilities, urban areas, or places where people live, disrupting lives and livelihood causing fear and anxiety, and leading to significant social and economic damage. The cost to clean up and recover following a moderately large RDD has been estimated to be billions of dollars. An RDD could effectively cause an area to be inaccessible for a long period of time". (FEMA, Statement for the Record, Glenn M. Cannon, 2007, p. 2)