Red risks

These risks have been rated as having high impact and high likelihood.

Failure of the national electricity transmission system (5 impact, 3 likelihood) 
Influenza-type disease (5 impact, 3 likelihood) 
Radiation release from overseas nuclear accident (4 impact, 4 likelihood) 
Variable rota power cuts (4 impact, 3 likelihood) 

Amber risks

These risks are more likely to happen, but will have a lower impact.

Systemic financial crisis (3 impact, 5 likelihood) 
Volcanic eruption (3 impact, 4 likelihood)
Public disorder (3 impact, 4 likelihood)
Fuel shortages at filling stations (3 impact, 4 likelihood)
Severe space weather (3 impact, 3 likelihood)
Fluvial flooding (3 impact, 3 likelihood)
The growth and spread of antimicrobial resistance (3 impact, 3 likelihood)
Emerging infectious disease (3 impact, 3 likelihood)
Drought (3 impact, 3 likelihood)
Disruption to or loss of telecommunications systems (3 impact, 3 likelihood)

Yellow risks

These risks are less likely to happen and will have a lower impact.

Water infrastructure failure or loss of drinking water (3 impact, 2 likelihood)
Aviation crash (3 impact, 1 likelihood)
Industrial action (firefighters) (2 impact, 5 likelihood)
Industrial action (public transport) (2 impact, 5 likelihood)
Industrial action (prison officers) (2 impact, 4 likelihood)
Accidental release of biological substance (2 impact, 4 likelihood)
Major social care provider failure (2 impact, 4 likelihood)
Technological failure at a retail bank (2 impact, 3 likelihood)
Railway accident (2 impact, 3 likelihood)
Major outbreak of animal disease (2 impact, 3 likelihood)
Surface water flooding (2 impact, 3 likelihood)
Poor air quality (2 impact, 3 likelihood)
Storms (2 impact, 3 likelihood)
Major fire (2 impact, 2 likelihood)
Large toxic chemical release (2 impact, 2 likelihood)
Accident involving high consequence dangerous goods (2 impact, 2 likelihood)
Gas supply failure (2 impact, 2 likelihood)
Food supply contamination (2 impact, 2 likelihood)
Building collapse (2 impact, 2 likelihood)
Industrial action (fuel supply) (2 impact, 2 likelihood)
Reservoir/ dam collapse (2 impact, 2 likelihood)
Coastal flooding (2 impact, 2 likelihood)

Green risks

These risks are considered to have a low impact.

Explosion at a high pressure gas pipeline (2 impact, 1 likelihood) 
Bridge closure or building collapse (2 impact, 1 likelihood)
Accidental release of biological pathogen (2 impact, 1 likelihood)
Small scale highly disruptive demonstration (1 impact, 5 likelihood)
Heatwave (1 impact, 4 likelihood)
Low temperatures and heavy snow (1 impact, 4 likelihood)
Influx of British nationals (1 impact, 4 likelihood)
Influx of foreign nationals (1 impact, 4 likelihood)
Radiation exposure from stolen goods (1 impact, 1 likelihood)
Insolvency affecting fuel supply (1 impact, 1 likelihood)
Earthquake (UK) (1 impact, 1 likelihood)