There are risk levels used by government organizations and other agencies to signify imminent danger and to warn the public about potential threats. These levels give insight into what could possibly be an attack or dangerous situation. 


This indicates that an attack is not imminent or highly unlikely. This is the lowest level of threat in every society.


This indicates that the attack is possible but unlikely to happen.


This indicates that an attack is likely to occur. This means the potential for attack is somewhat high.


At this level, an attack is highly likely to occur. 


This indicates that an attack is essentially certain in the nearest future.

The most important thing to do when warned by authorities about substantial, severe, or critical threat levels is to avoid the zone or areas facing that threat if possible. If you happen to be in the danger zone before a warning is issued and it is safe to evacuate the area without any risk or minimal risk, this action should be taken. However, each situation is unique and the direction of experts should be adhered to. Ensure to always remove yourself from such situations before things get critical and severe.