An emergency condition (EMERGCON) is a state of readiness that is separate from DEFCON, or defence readiness condition used by the United States, in that it incorporates civilian measures in addition to the DEFCON military measures.
Generally, EMERGCONs are a state of readiness following an ICBM (intercontinental ballistic missile) attack. Other forces go to DEFCON 1 during EMERGCONs.
There are two types of EMERGCONs:
- Defence Emergency: A major hostile attack on United States and/or allied forces overseas, and/or an overt action made against the United States. This must be confirmed by a unified commander or higher authority.
- Air Defence Emergency: A major hostile attack by aircraft or missiles seems probable, is imminent, or is taking place on the continental United States, Canada, or Greenland. This declaration is made by the Commander of the North American Aerospace Defence Command (NORAD).
Although the United States military has gone into defence readiness at various times (such as the Cuban Missile Crisis), it has never had a major EMERGCON.
Should not be confused with similar systems used by the US military, such as:
- Alert Condition (LERTCON).
- Emergency Condition (EMERGCON).
- Defence Readiness Condition (DEFCON).
- Force Protection Condition (FPCON), previously THREATCON.
- Readiness Condition (REDCON).
- Information Operations Condition (INFOCON), and its future replacement Cyber Operations Condition (CYBERCON).
- Watch Condition (WATCHCON), or the former Homeland Security Advisory System used by the United States Department of Homeland Security.
- Hurricane Condition (HURCON), a military developed scale.