Page type: primary-anchored (mirrors Independent Gas Transporters' Uniform Network Code)
Independent Gas Transporters' Uniform Network Code (iGT UNC)
The iGT UNC governs the commercial and operational arrangements for gas transportation on independent gas transporter (IGT) networks in Great Britain. IGTs are companies that own and operate gas distribution pipelines outside the main gas distribution networks, typically serving new housing developments and industrial estates.
Current version: 13.24 (26 September 2025) Legal basis: Gas Act 1986; GT Licence Condition 9 Code administrator: Talan (Critical Friend / secretariat) Source file: sources/igt-unc/igt-unc.md Canonical URL: https://www.igt-unc.co.uk/
What the iGT UNC does
The iGT UNC creates a common set of rules for all IGTs, so that gas shippers and suppliers deal with a consistent framework whether they are on an IGT network or a main distribution network. It covers: - Supply point administration (how customers are registered and switched) - Metering (installation, reading, validation) - Transportation charges and invoicing - Emergencies and safety - Gas delivery and offtake - User admission and termination
Relationship to the main UNC
The iGT UNC and the UNC are separate codes but deeply interdependent since Project Nexus (June 2017). The IGTAD (Independent Gas Transporters Arrangements Document), which is Part 5 of the UNC General Terms, governs the interface between IGT and main transporter networks. Many modifications are now cross-code (e.g., IGT169 aligning with UNC0701 and UNC0853).
Both codes share the CDSP (Xoserve) and UK Link system for central data services (Part N).
Structure (17 Parts)
| Part | Title | Pages | Key content |
|---|---|---|---|
| A | Introduction and Interpretation | 1-4 | Legal basis (GT Licence Condition 9), Pipeline Operator/User definitions |
| B | Capacity | 5-7 | Unmetered CSEP, pipeline capacity, DM capacity, downstream systems |
| C | Supply Point Administration | 8-33 | Five sub-parts (CI-CV): supply points, DM capacity/offtake, interruptibles, deregistration/isolation, new connections |
| D | Supply Meter Installation | 34-40 | Meter equipment, provision, prepayment meters |
| E | Meter Reading | 41-49 | Cyclic readings by supply class (1-4), estimated reads, performance assurance |
| F | Daily and Annual Quantities and Shrinkage | 50-52 | Demand determination, NDM sampling, reconciliation, pipeline shrinkage |
| G | Pipeline Transportation Charges, Invoicing, Payment and Code Credit | 53-83 | Charging, invoicing, payment terms, credit rules (longest Part) |
| H | System Maintenance and Planning | 84-87 | Programmed maintenance, system planning |
| I | Emergencies | 88-94 | Local emergency procedures, priority consumers, curtailment |
| J | Delivery and Offtake of Gas | 95-98 | Gas quality (off-spec gas), compensation, availability obligations |
| K | General | 99-125 | User admission, liability, confidentiality, force majeure, governing law, ancillary documents |
| L | Modification Rules | 126-170 | Full modification governance: Panel, workgroups, consultation, self-governance, SCR, cross-code |
| M | Definitions | 171-187 | Full defined terms register (17 pages) |
| N | CDSP and UK Link | 188-195 | Central Data Services Provider (Xoserve) arrangements |
| O | Derogation Rules | 196-204 | Framework for derogations from code requirements |
| P | Performance Assurance | 205-206 | PAC, performance framework, reporting |
| Q | Pipeline Entry Point Requirements | 207-214 | Gas entry provisions, quality specs for embedded entry (e.g., green gas) |
Key differences from the main UNC
- Uses "Pipeline Operator" instead of "Transporter" and "Pipeline User" instead of "User/Shipper"
- Made binding via a Framework Agreement (not directly a licence condition)
- No equivalent of the TPD's NTS-level provisions (entry/exit capacity, balancing) -- IGT networks connect downstream of the main distribution networks
- Supply classes mirror the UNC (Class 1-4) but with IGT-specific reading and estimation rules
- Part Q (Pipeline Entry Point Requirements) is important for green gas/biomethane injection into IGT networks
Governance
The iGT UNC Modification Panel manages code changes. Talan acts as the Critical Friend (code administrator/secretariat). Modifications numbered IGTxxx are assessed by the Panel and workgroups, consulted on, and either decided by the Panel (self-governance) or referred to GEMA (the Authority). The code includes provisions for Significant Code Review, cross-code implications, and Authority Send Back (Part L).
Key parties
| Party | Role |
|---|---|
| Pipeline Operators (IGTs) | Own and operate pipelines; licensed under Gas Act 1986 s.7(2) |
| Pipeline Users (Shippers) | Licensed gas shippers using IGT networks |
| Talan | Code administrator / Critical Friend |
| CDSP (Xoserve) | Central Data Services Provider (shared with UNC) |
| GEMA (Ofgem) | Regulator; approves/rejects certain modifications |
Cross-references
| Instrument | Nature of link |
|---|---|
| UNC | Parent code; IGTAD interface document; shared CDSP |
| Gas Act 1986 | Foundational statute |
| Gas Transporter Licence, Condition 9 | Legal basis for network codes |
| Retail Energy Code (REC) | CSS integration for switching (IGT158, IGT161) |
| IGTAD (UNC component) | Formal interface between IGTs and main transporters |
Character positions
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Last updated
2026-04-05 (initial build from two-pass ingest)