Fire Safety Labels for Solar Panels: BS 7671 Requirements, Locations and What to Check (UK 2026)

Fire safety labels on solar installations warn emergency responders that dangerous DC electricity is present even when the mains supply is isolated. Unlike conventional electrical systems that can be made safe by turning off the main switch, solar panels continue generating voltage whenever light hits them – potentially hundreds of volts DC that cannot be switched off from ground level. Proper labelling ensures firefighters know the risks before entering a property or working on the roof.

UK regulations require specific warning labels at key locations: the meter box, consumer unit, DC isolator, inverter, and anywhere firefighters might encounter DC cables or equipment. These labels must be durable, clearly visible, and use standardised wording and symbols. Your installer is responsible for fitting compliant labels, and their presence is checked during MCS certification inspections.

This guide explains what labels are required, where they must be placed, what they should say, why they matter for firefighter safety, and what homeowners should check to ensure their system is properly labelled.

Quick Overview

Why Fire Safety Labels Matter

The Solar-Specific Hazard

The Building Research Establishment’s fire safety and photovoltaic systems guidance is the definitive UK reference on this hazard – including the specific risks that BRE has identified from real fire investigations, where AC isolators have been mistakenly used in DC circuits, leading to heat build-up. For the underlying electrical-shock physics, see our complementary guide on can solar panels electrocute you.

Firefighter Safety Concerns

What Labels Achieve

UK Regulatory Requirements

Key Standards

For the broader earthing-and-bonding side of BS 7671 Section 712 – which covers the same parts of the regulations – see our guide on earthing and grounding solar systems. Both labelling and earthing fall under the solar-PV-specific section of the IET Wiring Regulations.

BS 7671 Requirements

MCS Requirements

Required Labels and Locations

Overview of Required Labels

Meter Box Label

Consumer Unit Label

Inverter Label

DC Isolator Labels

Label Content and Wording

Standard Warning Notices

Information to Include

Symbols Used

Example Label Texts

DC Cable Route Labels

Where Required

Cable Warning Labels

Loft and Roof Space

DC arc faults in unlabelled cable runs are one of the few real fire-ignition pathways in solar PV. Modern systems mitigate this with arc-fault detection circuitry built into the inverter – see our arc fault detection guide for the technical detail.

Label Specifications

Durability Requirements

Material Options

Colour Requirements

Size Requirements

Firefighter Information Box

What It Is

Contents

Benefits

Battery Storage Additional Labels

Battery-Specific Hazards

Battery Warning Labels

If you’ve added a battery to an existing solar system, the labels need updating to reflect the change. See our battery retrofit guide for what should be re-checked at the same time as the labels.

Combined PV and Battery Labels

Rapid Shutdown Labels

What Rapid Shutdown Is

Labels for Systems With Rapid Shutdown

Module-Level Electronics

A microinverter system inherently delivers most of what a “rapid shutdown” provides because the high-voltage DC string never exists – each panel converts to AC immediately. From a fire-safety labelling perspective, a microinverter system needs different wording to a string-inverter system because the DC hazard is much more localised.

Commercial and Large System Labels

Additional Requirements

Fire Strategy Documentation

Installer Responsibilities

Label Supply and Fitting

Documentation

If you’re checking whether an installer’s quote covers everything they should be doing – including label supply and fitting – our solar panel quote checker walks through the line items a compliant quote should always show.

Common Installer Mistakes

Homeowner Checks

What to Look For

Label Condition Check

Annual Visual Check

What If Labels Are Missing

Steps to Take

Where to Buy Labels

Firefighter Awareness

What Fire Services Know

Fire Service Guidance

How Labels Help Firefighters

For broader storm and incident risks – including post-event safety inspection – see our storm damage solar panels guide, which covers what to do (and what not to do) after any major weather or fire event affecting a solar installation.

Frequently Asked Questions

Basic Questions

Technical Questions

Summary

Fire safety labels are a critical but often overlooked aspect of solar installations. They serve one vital purpose: ensuring firefighters know that dangerous DC electricity is present even when the mains supply is isolated. Solar panels generate voltage whenever light hits them – this cannot be switched off remotely, and string voltages of 300-600V DC present serious shock and arc flash risks.

UK regulations require warning labels at all key points: the meter box (first point of entry for emergency services), consumer unit (where someone might assume isolating the mains makes everything safe), DC and AC isolators, and the inverter. Cable routes through the building should also be marked, particularly in loft spaces where firefighters might work without realising DC cables are present.

Your installer is responsible for supplying and fitting compliant labels as part of the installation. Labels must be durable enough to last the lifetime of the system – typically 25+ years – which means proper materials like engraved plastic or UV-stable vinyl rather than paper or card. The presence and condition of labels is checked during MCS inspections.

As a homeowner, you should visually check your labels annually to ensure they’re still present, legible, and securely attached. If any labels are missing, faded, or damaged, contact your installer to arrange replacements. These small labels could save lives in an emergency – they deserve the same attention as any other safety feature of your home.