Threat Levels
Terrorism threat levels are designed to provide a broad indication of the likelihood of a terrorist attack. There are five UK national threat levels.
| Threat Level | Response Level | ||
|---|---|---|---|
| Low | An attack is highly unlikely |
NORMAL | Routine protective security measures appropriate to the event |
| MODERATE | An attack is possible but not likely |
||
| SUBSTANTIAL | An attack is likely | HEIGHTENED | Additional and sustainable protective security measures reflecting the broad nature of the threat with specific vulnerabilities |
| SEVERE | An attack is highly likely |
||
| CRITICAL | An attack is highly likely in the near future |
EXCEPTIONAL | Maximum protective security measures to meet specific threats to minimise vulnerability |
Response Levels
Response levels, which tend to apply to sites, should provide a general indication of the protective security measures that need to be applied at a given time, depending on the current UK national threat level and any specific assessments of vulnerability and risk.
There are a variety of site-specific security measures that can be applied within each response level. These measures should not be made public, to avoid informing terrorists about what actions are being taken and to disrupt any potential reconnaissance they may wish to conduct.
The CT Menu of Tactical Options is a list of protective security measures that you may wish to consider implementing in the event of an increase to Critical and is available on ProtectUK.
Implementing as many protective security measures in this booklet as possible will also help you to ensure you are prepared and protected in the event of an incident.