Extension Lead Safety: What Every Tradesperson Should Know

Extension leads are on every site, and they're involved in more accidents than most people realise. A few basic precautions can prevent fires, shocks, and equipment damage.

Choosing the Right Lead

Not all extension leads are created equal. For site use, you need:

• Cable thickness: At least 1.5mm² for general use, 2.5mm² for high-power tools
• Length: As short as practical - longer cables mean more voltage drop
• Rating: Check the amperage matches your tools' requirements
• Construction: Heavy-duty rubber sheath, not domestic PVC

The Coiled Cable Problem

Here's something that catches people out: a coiled cable can't dissipate heat properly. A 13A rated lead might only handle 6A when fully wound. Always unwind extension leads completely before use, especially with high-power tools like heaters or circular saws.

Water and Electricity

Rain, puddles, damp concrete - sites are often wet. Keep connections off the ground and away from water. Junction box covers exist for a reason. If a lead gets wet, don't just wipe it dry and carry on. Dry it properly before the next use.

Daisy Chaining Dangers

Plugging one extension into another is tempting when you need extra reach. It's also a fire risk. Each connection adds resistance, generates heat, and increases the chance of failure. Use one appropriately-rated lead that reaches where you need it.

Regular Inspection

Before each use, check for:

• Damaged outer sheath
• Exposed inner cables
• Burn marks around plugs
• Loose connections
• Missing earth pins

PAT Testing

Portable Appliance Testing isn't just bureaucracy. Regular testing catches problems before they cause accidents. Keep records, replace failed equipment, and don't let cost-cutting compromise safety. A new extension lead costs far less than an injury claim.

Browse our electrical accessories for site-rated cables and connectors.