Homeland Security Advisory System
The
U.S. Homeland Security Office has established criteria for terrorism
alert levels. The chart below indicates how these federal levels correspond
to Metro's OPCON levels, or conditions that determine the city's
readiness and response to a community emergency.
The Homeland Security Advisory System provides a framework for the Attorney
General, in consultation with the director of the Office of Homeland
Security, to assign threat conditions that can apply nationally, regionally,
by sector, or to a potential target. Cabinet secretaries and other members
of the Homeland Security Council will be consulted as appropriate. Here
are some factors that are used to assess a threat:
- Is the threat credible?
- Is the threat corroborated?
- Is the threat specific and/or imminent?
- How grave is the threat?
| OPCON
1 |
Low risk of terrorist attacks. The following Protective Measures may be applied:
|
|
| Low
Condition Green |
||
| OPCON
2 |
General risk of terrorist attack. In addition to the previously outlined protective measures, the following may be applied:
|
|
| Guarded
Condition Blue |
||
OPCON
3 |
Significant risk of terrorist attacks. In addition to the previously outlined Protective Measures, the following may be applied:
|
|
Elevated
Condition Yellow |
||
OPCON
4 |
High risk of terrorist attacks. In addition to the previously outlined Protective Measures, the following may be applied:
|
|
| High
Condition Orange |
||
OPCON
5+ |
Severe risk of terrorist attacks. In addition to the previously outlined Protective Measures, the following may be applied:
|
|
| Severe
Condition Red |


