Manmade and/or terrorist threats can come from many places. These can include biological, radiological, and chemical threats.
Bioterrorism, or a biological attack, is the intentional release of germs or other biological substances such as toxins and poisons that can cause illness and death among people. The possibility also exists for a terrorist to use new, genetically-engineered agents that are harder to treat.
Radiological / Nuclear
“Nuclear” is not a scary word. In fact, nuclear power from plants like Comanche Peak near Glen Rose supply over 15% of the electricity used in the United States. A nuclear or radiological emergency would most likely be the result of an accident. But it’s possible that a hostile country could use a nuclear weapon or a “dirty bomb” could be used by terrorists.
A chemical emergency occurs when a hazardous chemical has been released and the release has the potential for harming people's health. Chemical releases can be unintentional, as in the case of an industrial accident, or intentional, as in the case of a terrorist attack.