Health and Safety
Executive / Commission
Pipelines health and safety
Networks of major accident hazard pipelines (MAH pipelines or MAHPs) are used to safely transport hazardous substances around Great Britain; however third party damage to MAH pipelines by landowners, utility and construction contractors and others poses a risk to workers and the public. In July 2004, 25 people died and more than 150 were seriously injured in Ghislenghien, Belgium following construction damage to a high pressure gas pipeline.
Anyone planning an excavation in the vicinity of a MAH pipeline should contact the pipeline operator at least 7 days before the start of any work. MAH pipelines are usually buried between 1 and 1.5 metres underground and can be identified by surface marker posts.
Pipelines conveying natural gas at pressures above 7 bar are classified as MAH pipelines. National Grid Gas plc and four other gas Distribution Network owners operate regional networks, which include 15,000 km of MAH pipelines. The ’dial-before-you-dig” contact numbers for the gas Distribution Networks are shown at right and anyone planning an excavation in these areas should contact the relevant gas Distribution Network operator before starting work.
National Grid Gas plc also operates the National Transmission System (NTS) which delivers gas to the Distribution Networks and other large consumers such as power stations and industrial sites. The NTS comprises 6,000 km of gas pipelines ranging in pressure from 38 to 85 bar. The layout of the NTS is shown in the map at right. Anyone planning an excavation in the vicinity of NTS pipelines should contact National Grid Gas on 0800 731 2961 or via Linesearch.
Linesearch provides a free online pipeline location service for thousands of Km of buried gas, petrochemical and oil pipelines in England, Scotland and Wales.
The pipelines and operators covered by Linesearch are shown in the map at right. Linesearch can be contacted on 0870 403 6484 or online at http://www.linesearch.org.
For further information contact HSE’s Gas and Pipelines Unit on 0114 291 2392 or go to HSE’s ‘Pipelines health and safety: Information’ webpage at www.hse.gov.uk/pipelines/information.htm