Cyber attack - gas infrastructure 

Impact 5
risk indicator
ID 11
Risk theme Terrorism
Impact & Likelihood
Impact key
5 Catastrophic
4 Significant
3 Moderate
2 Limited
1 Minor
Likelihood key
5 >25%
4 5-25%
3 1-5%
2 0.2-1%
1 <0.2%


This risk is featured in the full matrix, representing the averages of multiple different scenarios presented together in the ‘cyber attacks on infrastructure’ category.

Gas infrastructure may represent a potential target for cyber attacks. Cyber attacks may involve the encrypting, stealing or destroying of data upon which critical systems depend, or they may result in disruption to operational systems. This could lead to the failure of gas supply infrastructure. National response plans would be initiated to protect critical services as far as possible.


The reasonable worst-case scenario is based on a cyber attack on a system critical to gas transmission, causing a significant loss of gas supply. Domestic gas customers in the directly impacted region would lose their gas supply. There would be casualties and fatalities as a result of a lack of heating, lack of access to necessary medical treatment, exacerbation of an existing condition, or limited ability to safely use gas- fired cookers. However, impacts would depend on the scale of disruption.

Emergency procedures could be required to safely balance and maintain pressure on the gas network by stopping supply to large industrial users, including electricity generating stations. Priority of gas supply would be given to domestic users (as they take longer to reconnect following disconnection for safety reasons). Within this process, some critical sites would be prioritised for supply. Disconnecting gas supply to electricity power stations could cause a shortfall in electricity generation. In the event of a prolonged electricity supply shortfall, rolling power cuts lasting 3 hours at a time may be required to balance supply and demand.

Within this process, some critical sites would be protected from disruption, with the remaining disconnections being evenly distributed across Great Britain. Further information on established emergency procedures for a gas or electricity emergency can be found in the National Emergency Plan for Downstream Gas and Electricity.

Response capability requirements

There would need to be preparations in place to support wider recovery and the continued operation of multiple sectors. This includes functioning telecoms, emergency services and fuel distribution.


Restoration of the affected gas infrastructure could take approximately 3 months, at which point rolling power cuts would no longer be required, as gas supplies to electricity power stations would resume. It would take a further week for industrial gas customers to be fully restored and weeks or months for some sites to return to service. It would take several months to restore domestic gas customers impacted by the initial loss of supply. A cyber attack could mean that recovery takes longer than expected, depending on the sophistication of the attack and damage to the system.