Insulated Tools for Electricians UK: IEC 60900 Guide

Insulated Tool Marking Reference

• 1000V marking — confirms the tool is rated for use on systems up to 1,000V AC or 1,500V DC under IEC 60900. This covers the vast majority of low-voltage electrical installations in the UK, including 230V single-phase and 400V three-phase systems.
• Double-triangle symbol — the two overlapping triangles symbol on an insulated tool indicates compliance with IEC 60900. This is the universal marking recognised across Europe and internationally.
• VDE mark — the VDE oval mark indicates independent testing and certification by VDE (Germany). This is the gold standard for insulated tools and provides the highest level of assurance. GS mark (Geprüfte Sicherheit) is another German safety mark that may accompany the VDE mark.
• Colour coding — Knipex and Wiha use red/yellow insulation; other manufacturers use different combinations. Importantly, the inner layer must be a contrasting colour to the outer — if you see the inner colour breaking through, the tool's insulation is compromised. Take it out of service immediately.

• Three-part test — live work is only permitted if: (1) it is unreasonable in all the circumstances for the conductors to be dead; (2) it is reasonable in all the circumstances for the person to be at work on or near those conductors; and (3) suitable precautions are taken. All three conditions must be satisfied simultaneously.
• Employer authorisation required — the employer must assess and authorise live work. Self-employed electricians must carry out and document their own risk assessment. A verbal "it's fine" is not sufficient — the assessment must be documented and the worker must be trained in live-working techniques.
• Required precautions for live work — IEC 60900 insulated tools, insulating gloves (Class 00 minimum — rated to 500V AC, tested to 2,500V), face shield rated to the arc flash energy level, a second competent person present at all times, and a rescue plan including first aid provision.
• Not a cost-saving measure — live working to avoid the inconvenience or cost of isolation does not satisfy the Regulation 14 test. "The customer didn't want the power off" is not a defence. HSE inspectors are experienced at identifying rationalisation after the fact.

Insulating Glove Classes (BS EN IEC 60903)

Rubber insulating gloves are classed by maximum working voltage. Select the class for the system voltage you are working on — for typical 230V / 400V LV work, Class 00 or Class 0 is used.

Insulating gloves are normally worn with leather over-gloves for mechanical protection and must be air-tested for pinholes before each use.

• Knipex — market leader for insulated pliers and cutters. Their VDE insulated range covers combination pliers, long-nose pliers, side cutters, cable shears, strippers, and crimping tools. The Knipex 98-series is widely used by UK electricians. Known for exceptional build quality and precision.
• Wiha — leading brand for insulated screwdrivers, nut drivers, and pliers. Their SlimBit and SlimLine insulated ranges are popular for work in restricted spaces. VDE-certified and available from all major UK electrical wholesalers. Excellent ergonomics.
• Wera — the preferred choice for many UK electricians for insulated screwdrivers, particularly in Torx and Pozidriv variants. VDE-certified. Wera's Kraftform handle design is ergonomically well-regarded for repetitive screwdriving tasks common in electrical installation work.
• Bahco — Swedish brand (owned by Snap-on) offering VDE-certified insulated pliers and cutters at a competitive price point. Good quality and widely available. A solid mid-range option for electricians who want VDE certification without Knipex pricing.
• CK Tools (Carl Kammerling) — UK-focused brand offering a broad range of IEC 60900 insulated tools. Popular in the UK trade market. More affordable than the German premium brands while maintaining compliance with IEC 60900.

• Screwdrivers — slotted and Pozidriv in multiple sizes, plus Torx for modern equipment. VDE-insulated screwdrivers are the most commonly carried insulated tool among UK electricians.
• Pliers and cutters — combination pliers, long-nose pliers, side cutters (snips), and end-cutting pliers. Knipex dominates this category.
• Strippers and crimpers — insulated cable strippers and crimping tools for working on terminated conductors in live panels.
• Spanners and nut drivers — insulated nut drivers (commonly in 10mm, 13mm, and 17mm) and insulated open-ended spanners for work on terminals and bus connections.
• Cable knives — insulated electrician's knives for cable preparation adjacent to live conductors. A non-insulated knife blade contacting a live conductor is a serious electrocution risk.

Inspection & Test Triggers at a Glance

• Visual inspection before each use — IEC 60900 requires tools to be visually inspected before use. Check for cuts, cracks, punctures, swelling, hardening, or discolouration of the insulation. Check that the inner contrasting layer is not visible through the outer layer. Remove any tool with visible damage from service immediately.
• Periodic electrical testing — the IEC 60900 standard recommends periodic testing of insulated tools and protective devices. This involves applying 10,000V AC for one minute across the insulation and measuring the leakage current, and must be carried out by a competent person with appropriate equipment. While annual testing is widely adopted as industry best practice in the UK, IEC 60900 does not mandate a specific interval — employers and duty holders should set their own inspection frequencies based on risk assessment under PUWER.
• Record keeping — maintain a record of insulated tool inspections and tests. This demonstrates compliance with PUWER and PPE regulations and is useful evidence in the event of an incident investigation.
• No field repair of insulation — damaged insulation on an IEC 60900 tool cannot be repaired on site with insulating tape or similar. The tool must be withdrawn and either returned to the manufacturer for assessment or destroyed. Attempting to repair damaged insulation creates a false sense of security and could cause electrocution.