Offshore Pipeline Integrity Management - Operational Guidance for Inspectors
This operational guidance is for inspectors carrying out offshore pipeline integrity management inspections. It describes four core inspection topics and sets out success criteria against these. It provides a consistent framework for judging compliance, assigning performance ratings and determining follow up actions. Relevant legislation, technical standards and other information sources are referenced. There is separate operational guidance for onshore pipeline integrity management.
For offshore pipelines transporting hazardous substances, the consequences of poor integrity management have the potential to be catastrophic for the resident workforce on offshore installations and other users of the sea. A principal aim in the Energy Division (ED) Offshore Oil & Gas Sector Strategy is to ensure that the integrity of offshore installations, wells, well control equipment and pipelines are ensured throughout their life cycle. Targeted inspections based on this operational guidance will support ED's strategy by:
- systematically evaluating the adequacy of pipeline operators' arrangements for pipeline integrity management against a consistent set of criteria; and
- ensuring that appropriate enforcement action is taken in cases where legal minimum standards are not met.
During offshore pipeline integrity management inspections, inspectors should:
- compare standards of performance for the four core topics (Appendix 1) against the relevant success criteria (Appendix 2);
- use performance descriptors (Appendix 3) to determine the appropriate performance rating and EMM initial enforcement expectation;
- consider how and when any issues raised during the inspection are to be closed out, making use of the COIN issues tab and taking formal enforcement action where appropriate.
Pipelines can be subject to a range of degradation mechanisms (e.g. corrosion, erosion and embrittlement). This progressive deterioration is known as ageing. The issue of pipeline ageing and integrity is particularly significant for the UK offshore oil and gas industry because many hydrocarbon pipelines within the United Kingdom Continental Shelf (UKCS) are over 30 years old. Oil and gas supplies continue to be sourced from existing UKCS infrastructure and pipelines may need to operate for many more years to meet UK energy demands. It is vital that these pipelines, some of which exceed their original design life, continue to operate with minimal risk to people, the environment and the security of the UK's energy supplies.
Pipelines can fail through damage mechanisms that are not age-related, e.g. dropped object damage, accidental overpressure. In order to comply with their legal duties, pipeline operators need to identify, assess and properly control significant potential threats to their pipelines. They should also make appropriate use of technical advances (e.g. in defect assessment and repair methods) to ensure that the risk of pipeline failure continues to be as low as reasonably practicable (ALARP).
Poor subsea pipeline integrity management also poses risks to the environment. The Department for Energy and Climate Change (DECC) is responsible for environmental matters and HSE and DECC operate under a memorandum of understanding (MOU) to effectively co-ordinate their regulatory activity on the UKCS. Under the MOU, HSE and DECC may share relevant information following inspections or investigations. This may include aspects associated with pipeline ageing and integrity where UKCS pipeline infrastructure or security of supply may be compromised. Appendix 4 gives further details about environmental considerations and the role of DECC.
Appendix 5 gives further information about relevant legislation, and Appendix 6 provides references to technical standards and other useful resources.
Pipeline integrity management is a strategic priority topic and inspections should be included in the intervention plans (IPs) for offshore pipeline operators. Where other topics have been identified as local priorities, inspectors should take this into consideration when preparing their IPs. ED5's risk ranking arrangements should be used to assist inspectors when determining intervention frequencies and targeting.
Rating and recording
Appendix 1 describes the four core topics and Appendix 2 describes the associated success criteria that inspectors should consider during inspections of offshore pipeline integrity management. Not all of the success criteria will apply in every case and inspectors should only consider those that are relevant at each inspection. If any success criteria are not met, inspectors should assess how serious the consequences could be. This will determine the performance ratings that they should assign and the enforcement action to be taken, if any.
Performance ratings should be entered on the Inspection Rating Form (IRF) tab of the relevant PSR Intervention Plan Service Order. Separate ratings should be entered for each of the four core topics against descriptors on the IRF tab as follows:
|Core topic||Description of topic on IRF rating tab|
|Pipeline design compliance and the identification and assessment of integrity management arrangements||Pipeline Design Compliance|
|Pipeline safety management system (SMS)||Pipeline SMS|
|Implementation of the pipeline integrity management process||Pipeline Integrity Management|
|Emergency planning and preparedness||Emergency Response|