NGET Temporary Works Training Requirements: What Your TWC and TWS Need

If you coordinate or supervise temporary works on a National Grid Electricity Transmission (NGET) project, the first question is usually the same: what training do I actually need? The honest answer is that NGET temporary works training requirements go further than most sites. NGET sets its own minimum standard for Temporary Works Coordinators (TWC) and Temporary Works Supervisors (TWS) in its Supplier Requirement NG/ET/SR_163 Management of Works.

Issue 2 of SR163 came out in April 2026 and it tightened things up. In this post I’ll walk you through what NGET asks for, what’s changed, and the kind of training main (Tier 1) contractors commonly accept, from the CITB TWCTC and CITB TWSTC to HSG47 HV Substations, GS6 and Impressed Voltage courses such as IV Awareness and IV for Managers. Please read my caveat before the table. It matters!

Why Is Temporary Works Different on NGET Sites?

Because the site is live. Temporary works on NGET projects often sit inside or right next to live high voltage substations, under overhead lines or near HV cables. That brings hazards you simply don’t meet on a typical building site: buried earthing systems, safety clearances to live conductors, and Impressed Voltage (voltage induced on to metalwork, scaffolds and cables by nearby live circuits). SR163 expects the people managing your temporary works to understand those hazards, not just the general principles of BS 5975.

How Are TWCs and TWSs Appointed on NGET Projects?

A course certificate on its own won’t get you there. SR163 section 3.5 asks the contractor to do a lot more:

•  The contractor formally assesses each TWC and TWS, and their Designated Individual (DI) nominates them.

•  Each one gets a certificate of authorisation setting out the scope of their authority.

•  The contractor confirms the assessment and authorisation in writing to NGET’s Client Representative.

•  TWCs and TWSs keep a record log of the projects where they carry out the role. This feeds into reauthorisation, at least every three years.

•  Both a TWC and a TWS must be appointed before works start (section 5.6), and the contractor’s Temporary Works procedure goes to NGET at tender stage for review and acceptance.

What Changed in SR163 Issue 2?

If you trained against Issue 1, these are the changes to look out for:

• HSG47 underground services training must now include working in a HV environment, for both the TWC and the TWS.
• Impressed Voltage training is now listed for the TWC.
• The TWS must complete a recognised TWS training course. Issue 1 referred to a TWC course for both roles.
• The section numbers have moved. The TWC and TWS requirements are now in section 3.5 (previously 2.5) and Temporary Works is in 5.6 (previously 4.6).

What Training Does NGET Require for a TWC and TWS?

The left-hand column below sums up NGET’s minimum requirements from SR163 Issue 2, section 3.5. The right-hand column gives examples of the training or evidence Tier 1 contractors commonly accept against each one, with links to the courses we run.

What Else Does SR163 Expect from the TWC?

Don’t skip Appendix A! It adds client-specific risk controls that every TWC needs to know about:

•  Buried earthing: treat it as an underground service under HSG47, and never cut, move or disturb it without a competent designer and NGET’s agreement. Our HSG47 HV Substations course covers safe digging in this environment.

•  Scaffold guards: they must meet the clearances in ENA TS 43-8 Overhead Line Clearances and the National Grid Safety Rules, with accurate setting out (for example by GPS) where position matters.

•  Impressed Voltage: the TWC works with the Principal Designer Rep so that Impressed Voltage hazards are on the Hazard Register and dealt with in the temporary works design. RAMS, permits to load and unload, and inspection forms must refer to them. Designers may find EUSR Impressed Voltage for Designers & NG SR/234 Overview useful.

How Should You Prepare Before Mobilisation?

My advice is simple. Plan early and the site runs itself. Leave it late and it bites!

•  Ask the Tier 1 for its Setting to Work requirements and its minimum training matrix as early as you can. Ideally at tender.

•  Map each TWC and TWS against every line in the table above, and close the gaps before the six-week run-up to site mobilisation.

•  Keep the record log up to date and put the reauthorisation date in the diary. It comes round at least every three years.

•  Keep certificates, the authorisation letter and the written confirmation to the Client Representative together, ready for audit.

Frequently Asked Questions

Is the CITB TWCTC enough to be a TWC on an NGET project?

Not on its own, I’m afraid. SR163 also asks for a relevant qualification (or equivalent knowledge), experience, and training in work at height, HSG47 including HV environments, confined spaces, GS6 and Impressed Voltage, followed by a formal assessment and written authorisation by the contractor. The Tier 1 may add its own requirements on top.

Does a Temporary Works Supervisor need the TWC course?

No. SR163 Issue 2 asks for a recognised TWS training course, such as the CITB TWSTC. Issue 1 referred to a TWC course for both roles, so it’s worth checking which one your TWS actually holds.

How often must TWCs and TWSs be reauthorised on NGET projects?

At least every three years. Their record log of projects supports the reauthorisation.

My CITB TWCTC or TWSTC certificate is valid for 5 years, but NGET wants reauthorisation every 3 years. Do I need to redo the training?

No, not just because of the three-year cycle. NGET’s reauthorisation is about your authorisation, not your course certificate. Your Designated Individual (DI) reviews your competence using your record log of the projects where you’ve acted as TWC or TWS, and reauthorises you with a new certificate of authorisation. That’s then confirmed in writing to NGET’s Client Representative. Your CITB certificate stays valid for its five years. Book a refresher before it runs out, and check whether your Tier 1 wants refresher training sooner.

Does the TWS need Impressed Voltage training?

SR163 lists Impressed Voltage training for the TWC. Many Tier 1 contractors ask for it for the TWS too, so check their requirements.

We’re working outside a live substation. Surely SR163 and the enhanced temporary works training don’t apply?

In most cases, yes, they still apply. SR163 covers the management of construction sites and construction surveys on NGET projects, not just work inside a live substation, and the TWC and TWS requirements in section 3.5 apply to anyone appointed to those roles on the project. Work outside the substation fence often carries the same hazards: overhead lines and Impressed Voltage on overhead line and cable routes, buried services and earthing, and scaffold guards near live conductors. Some controls are location-specific. For example, the extra safe digging precautions in section 5.12 apply when you’re working in a substation under a National Grid Safety Document. If you think a requirement doesn’t apply to your scope, agree it in writing with the Tier 1 and NGET’s Client Representative before work starts.

Our project has no confined spaces. Do I still need confined space training?

Plan on yes. SR163 section 3.5 lists confined spaces, work at height, HSG47 and GS6 training as minimum requirements for anyone appointed as TWC or TWS on NGET projects. It doesn’t make them depend on the scope of one job. TWCs and TWSs often move between projects, and temporary works such as deep excavations, chambers and cofferdams can create confined spaces of their own. If your work genuinely has none, ask the Tier 1 whether it’ll accept a lower level, such as City & Guilds 6160-01 low risk confined spaces, and get the answer in writing rather than assuming it isn’t needed.

Book Temporary Works and National Grid Training with Pragmatic Consulting

We deliver the CITB TWCTC and CITB TWSTC, along with the National Grid training and safety courses mentioned above. If you’re not sure where your team stands, get in touch and I’ll happily help you plan the training your temporary works team needs before mobilisation. See all our CITB accredited courses or contact the team.