Accidental fire or explosion at an onshore fuel pipeline

Impact 5
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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 involves an onshore pipeline that transports petroleum and other fuels. Although pipelines are a safe and cost-effective mode of fuel transportation, accidental damage and loss of containment of flammable fuel could potentially lead to fire and explosion. Operators of these pipelines have a legal duty to prevent accidents and to mitigate their consequences. The Health and Safety Executive develops and enforces legislation, standards, codes of practice and guidance to ensure that operators fulfil their responsibilities effectively.


The reasonable worst-case scenario for this risk concerns an accidental fire or explosion occurring at an onshore fuel pipeline situated close to a populated area. The ignition of flammable fuel under high pressure would result in a loud explosion, which could cause a crater, destruction of buildings, fatalities and casualties, and evacuation from homes up to 1km around the site. Depending on the fuel involved, there could be long-term environmental contamination. Additionally, up to 1,000 people would require temporary shelter or accommodation, with a number of these potentially requiring longer- term temporary accommodation if their property is seriously damaged.

Key assumptions

It is assumed that the incident is accidental and happens close to a populated area. The pipeline can quickly be isolated following the initial fire or explosion, so that demands on emergency responders are substantial but short-lived.


The extent and severity of impacts would depend on a variety of factors including pipeline contents, time of day/ night, the time taken to isolate the pipeline, and its location. The release of certain fuels from a pipeline would pose a greater hazard to the human population compared to others, depending on their flammability and combustibility.

Response capability requirements

The Pipelines Safety Regulations 1996 do not require local authorities to prepare emergency plans with respect to fuel pipelines, but they are required to plan for emergencies that could happen in their area under other legislation. Pipeline operators are also required to establish emergency procedures for such pipelines. There would be a need
for specialist treatment, surge capacities and appropriate recovery and storage for no-notice mass fatalities and casualties. Responders may require personal protective equipment (PPE). Some temporary evacuation and shelter arrangements may be required for displaced people, along with search and rescue teams to locate trapped people. Site clearance plans would be required for the removal of rubble and debris at a local level, and for decontamination of the environment.


The health effects arising from exposure to the effects of fire and explosion are likely to be acute but some will continue beyond 5 years. Psychological support may need to be made available to those affected. Making the area safe and treating environmental damage may take up to 5 years.