Portable Appliance Testing (PAT) is an essential part of maintaining electrical safety in workplaces, rental properties, and public buildings. While many people have heard of PAT testing, few fully understand what actually happens during the process.
This step-by-step guide will walk you through what to expect when your appliances are PAT tested.
Step 1: Preparation and Planning
Before testing begins, the PAT engineer will:
- Identify all appliances that need testing (anything that plugs into a socket).
- Work with you to minimise disruption, often testing equipment outside of peak working hours.
- Assign each appliance an ID number for record-keeping.
Tip: It helps to have all appliances accessible and plugs unplugged where possible.
Step 2: Visual Inspection
The first stage is a detailed visual check to spot obvious signs of damage or wear, such as:
- Frayed or split power cables
- Cracked or damaged plugs
- Loose wires or exposed conductors
- Burn marks or overheating signs
- Incorrectly fused plugs
This stage alone can identify many unsafe appliances before any electrical testing begins.
Step 3: Electrical Testing
Next, the tester uses a PAT testing machine to check the appliance’s electrical safety. Depending on the appliance type, tests may include:
- Earth continuity test – Ensures the earth connection is safe and effective.
- Insulation resistance test – Checks that the insulation around wiring prevents electric shock.
- Polarity test – Confirms the wiring inside the plug is correct.
- Leakage current test – Ensures no dangerous current is escaping.
Not all appliances need every test — the engineer will select the right checks for the type of equipment.
Step 4: Labelling
After the appliance is tested, it is clearly labelled with a PASS (usually green) or FAIL (usually red) sticker. The label will usually include:
- Appliance ID number
- Date of the test
- Name/ID of the tester
- Next recommended test date
This gives staff and users instant reassurance about whether the equipment is safe.
Step 5: Recording Results
All test results are logged in a PAT testing report. This document provides a full record of:
- Each appliance tested
- Test results and outcomes
- Any failed appliances and recommended actions
The report is essential for compliance and can be shown to insurers, auditors, or regulators if needed.
Step 6: Dealing with Failures
If an appliance fails, it will be:
- Clearly labelled as DO NOT USE
- Removed from service immediately
- Either repaired (if cost-effective and safe) or replaced
This ensures unsafe appliances don’t find their way back into use.
Final Thoughts
PAT testing is a straightforward but vital process. By following these steps, a qualified engineer helps ensure your electrical equipment is:
- Safe to use
- Compliant with UK safety regulations
- Properly documented for audits and insurance
Whether you’re a business owner, landlord, or school administrator, understanding the PAT testing process helps you plan ahead and keep your environment safe.