SPC/ENFORCEMENT/140
This SPC helps to clarify the legal and operational issues in cases where a gas distribution network operator (DNO) takes longer than 12 hours to prevent a gas escape following a PRE. It describes how reasonable practicability applies to GSMR Regulations 7(4) and 7(10) by considering circumstances where it may not have been reasonably practicable to prevent a gas escape within 12 hours of a PRE. This SPC should be used by inspectors during investigations of gas escapes from gas distribution pipelines.
1. Gas conveyors are required by GSMR to respond to public reports of gas escapes and the procedures that they follow to achieve this are included within their GSMR Safety Cases.
2. Where a gas escape is confirmed following a PRE, GSMR requires that the gas escape should be prevented within 12 hours of receipt of that PRE. However, GSMR offers a defence to this duty on the grounds of reasonable practicability. If the gas conveyor is able to prove that this defence applies to a gas escape, the work necessary to prevent it may be deferred beyond 12 hours.
3. Gas conveyors should ensure that the deferral of action to prevent a gas escape within 12 hours only takes place where the decision to so can be robustly justified. The principles that a gas conveyor should consider when determining whether or not to defer the prevention of a gas escape beyond 12 hours are discussed in this SPC.
4.GSMR Regulation 7(11) permits a gas conveyor to appoint another body to act as the emergency service provider and attend PREs on their behalf. This enables dutyholders who convey gas in small networks (like those found at some University and hospital sites) to sub-contract the emergency service provision for their networks to larger, more specialist organisations better able to take on this role. In practice this means that the local gas DNO will usually be responsible for attending PREs in any given area.
5. Regulation 7(4) of GSMR states:
‘Where any gas escapes from a network the person conveying the gas in the part of the network from which the gas escapes shall, as soon as is reasonably practicable after being so informed of the escape, attend the place where the gas is escaping, and within 12 hours of being so informed of the escape, he shall prevent the gas escaping.'
6. Regulation 7(10) of GSMR states:
In any proceedings against a person for an offence consisting of a contravention of paragraphs (4) or (5) above [i.e. regulations 7(4) or 7(5)] it shall, in so far as the contravention is not preventing the escape of gas within the period of 12 hours referred to in those paragraphs, be a defence for the person to prove that it was not reasonably practicable for him effectually to prevent the gas from escaping within that period, and that he did effectually prevent the escape of gas as soon as it was reasonably practicable for him to do so.'
7. Therefore gas conveyors are required by GSMR to:
However if the gas escape is not prevented within 12 hours then the gas conveyor may offer the defence that it was not reasonably practicable to have done so, provided they prevented the escape as soon as was reasonably practicable after 12 hours.
8. The prevention of a gas escape can be accomplished by ceasing the flow of gas to the escape or repairing it. The repair may be either temporary or permanent.
9. Regulations 7(4) and 7(10) of GSMR should only be applied to specific incidents where an escape of gas has occurred.
10. There are two clear parts to Regulation 7(4) of GSMR:
11. If a specific gas escape is not prevented within 12 hours then the gas conveyor is in breach of Regulation 7(4). Regulation 7(10) offers a defence to this breach and has two parts:
12. In considering any defence under Regulation 7(10) both parts must be addressed. It is not sufficient for the dutyholder to rely on the fact that a gas escape was prevented as soon as was reasonably practicable after 12 hours.
13. Where a DNO has made a decision based on reasonably practicability not to prevent a gas escape within 12 hours of receipt of a PRE, this is known as either a 'deferred' or 'programmed' gas escape. The decision-making process used by the DNO to defer a gas escape is, in effect, a prioritisation system.
14. Where Regulation 7(4) has been breached, the application of the prioritisation system can be used to provide a defence under Regulation 7(10). The defence will be in three parts:
15. Circumstances where it may not be reasonably practicable for a DNO to prevent a gas escape within 12 hours of receipt of a specific PRE, and where the gas escape was prevented as soon as was reasonably practicable afterwards, are given below.
16. Conversely, instances where it may have been reasonably practicable to prevent the gas escape in 12 hours include the following.
Neither of the above lists is exhaustive.
17. It is possible that the repair of a gas escape which was started within 12 hours of receipt of the PRE may, during the course of the repair, be reassessed using the DNO's prioritisation system. If the repair of the gas escape is subsequently deferred the DNO will be in breach of Regulation 7(4). In this case the DNO will have to rely on the same Regulation 7(10) defence as with an immediate repair deferral.
18. The duty described in GSMR Regulation 7(4) and the defence provided in Regulation 7(10) both make it clear that the intention of the legislation is to prevent an escape in response to a specific incident, not to limit risk across a DNO’s undertaking as a whole.
19. The provision of sufficient numbers of operatives by a DNO to prevent gas escapes within 12 hours will have a bearing on its response to a specific PRE and how it meets its Regulation 7(4) duty.
20. The DNO should interpret Regulation 7(4) as requiring it to provide resource, and prioritise its use, in compliance with the arrangements set out in its GSMR safety case. Any investigation into how the DNO complies with its safety case by making available sufficient resources across the DNO as a whole is subject to Regulation 5 of GSMR.
21. SI3 staff should apply this guidance when investigating incidents where PRE deferral may be a relevant factor.
