NTS to LDZ Meters – Audits & Validations

1. NTS to LDZ Meters – Audits & Validations Created by Alison Chamberlain on behalf of Transporters, for meeting 6th August, 2010, 31 Homer Road Solihull

2. Appointment of Auditors • External independent auditors appointed under normal procurement tendering processes employing primarily technical considerations with financial considerations considered to be of secondary importance. • Interested parties tendered against document GMR00022 this is a jointly developed and common DN document and Transmission’s Measurement Assurance Group and Ofgem have/had no objection to this approach and in fact wanted a common approach to be developed. • The auditors are UKAS accredited (and independently audited themselves). The United Kingdom Accreditation Service is the sole national accreditation body recognised by government to assess, against internationally agreed standards, organisations that provide certification, testing, inspection and calibration services. Accreditation by UKAS demonstrates the competence, impartiality and performance capability of these evaluators.

3. The Audit • Choice of sites – selection criteria applied and many factors are taken into account. (includes such considerations as complex risk factors applied to each relevant contributor for each meter, volume throughput, number of days since last audit, previous audit findings, metering technology type, balance across networks) – balanced against the normal validation cycle. • Presented to and agreed with Ofgem. As an example 10-12% of National Grid Distribution offtakes are chosen each year. (constraints – budget, site technician and central specialist technical support from Network Integrity required). • Practical considerations – co-ordinating dates for E&I, DCS (resource management) local site expertise, the audit company, pressure management, Network Integrity etc.

4. Audit Findings • National Grid Transmission get to view the output • Performance is viewed in relation to uncertainty and against the specific supplemental agreement. • Findings are categorised 1= most serious, 3= least serious & comments. • Report provided to Ofgem who seek an action plan and a liaison meeting is held (with Ofgem and the auditors present). • The action plan will, detail such actions as: • Work to be done on site • Competence • Research • Anything relevant • No action required and why.

5. Validations OAD Section D3 • "validation" means validation that Measurement Equipment is reading within the Permitted Range and without systematic bias; and "validate" and "validated" shall be construed accordingly. • the "Validation Procedures" are the procedures established by the Parties for validation of Measurement Equipment, comprising (as applicable) the documents known as T/PR/ME/2 parts 1, 2 and 3 and T/PR/GQ/3. • 3.1.4 The upstream Party shall be entitled, but shall not be obliged, at its own cost to attend and witness any validation carried out by the downstream Party in accordance with this paragraph 3. • NGT are exercising their right to witness validations and they issue a report detailing any findings. Issues are picked up and dealt with appropriately. • Every Offtake will be validated within a 12 month period and once started the validation should be completed within one month.

6. 3.3 Exceptional Validation • 3.3.1 The upstream Party shall be entitled to request that a validation of Measurement Equipment (or any component thereof) be carried out at any time, by notice to the downstream Party specifying the Offtake and the Measurement Equipment or component thereof to be validated and the upstream Party's reason/s for requesting such validation.

7. Ofgem • SGS has a contract with Ofgem to be the “Gas Examiners”. • A guidance document and capture spreadsheet which is used by the Gas Examiners to undertake pertinent metering checks during their normal Gas Examiner duties has been jointly developed in conjunction with Advantica (now GL) and SGS . • The completed spreadsheet is provided to the Network Technician at the time of visit. The spreadsheet contents are also uploaded to the SGS website by the Gas Examiner. The website automatically notifies the Responsible Engineer of any issues and a suitable response has to be made which is reviewed and accepted as appropriate by the lead SGS Gas Examiner.

8. Other parties • Distribution Control Centre/s - monitor real time critical alarms – all alerts are actioned for every site for every day. This can include a request to investigate system condition remotely and/or technician call out to resolve. (Information can also flow between National and area control). • Network Integrity/Equivalent dept - monitor detailed alarms and errors post Gas Day when data becomes available. This is a more detailed analysis. Each issue is investigated and documented. Anything requiring further investigation is dealt with. • Joint Office – now lodge all Significant/Meter Error Reports.

9. Information To facilitate continual improvements the responsible managers within each DN get copies of:- • The audit reports, • Transmission’s witnessing reports • The SGS ‘meter check’ spreadsheets data via the SGS website • Meter Error Reports (access via the Joint Office Website). NGT’s information (‘meter issues’ which includes a synopsis of the MERs). • NGTs validation acceptance report (spreadsheet) • Validation M.I. extracted from system (spreadsheet)