What Safety Standards Apply to High-Voltage Substation Construction in the UK?
- Akriti Kumari
- Nov 20
- 2 min read
High-voltage (HV) substation construction in the UK is governed by a strict set of safety standards to ensure reliability, compliance, and risk-free operations. For utility operators, EPC contractors, and renewable developers, understanding these requirements is not optional—it’s essential.
In this guide, VSS Power breaks down the most important UK safety standards and how they apply to HV substation engineering and construction.
1. BS EN 61936 – The Foundation of HV Installation Safety
BS EN 61936-1 defines the core safety requirements for electrical power installations above 1 kV AC. It covers:
Clearances & insulation levels
Earthing design
Protection systems
Fire safety
Equipment layout spacing
This is the baseline for all HV substation construction in the UK.
2. CDM 2015 Regulations
All substation projects must follow Construction (Design & Management) Regulations 2015.This ensures:
Proper risk assessments
Competent HV engineers
Safe installation practices
Documentation and site safety plans
At VSS Power, CDM compliance is built into every UK project delivery.
3. BS 7671 (IET Wiring Regulations)
While mostly used for LV systems, the HV sections detail rules for:
Cable installations
Earthing
Safety clearances
Protection schemes
4. ENA Technical Reports (ENA TS / ER Standards)
The Energy Networks Association sets utility-level compliance standards, including:
ER G99 / G5/5 for grid integration
ENA TS 41-series for protection
ENA earthing standards
These are critical for substation projects tied to UK grid operators like UKPN, SSE, National Grid, and SP Energy Networks.
5. Health & Safety at Work Act (HASAWA)
Every HV site must maintain strict safety controls for:
Arc flash protection
Electrical hazards
Work permits (PTW)
Lock-out/tag-out (LOTO)
Why Work With VSS Power?
VSS Power ensures full compliance, delivering design, engineering, testing, and commissioning for UK-based HV substations.
Need a fully compliant HV substation design or construction partner in the UK? Contact VSS Power for engineering, studies, and commissioning support.
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