Portable Appliance Testing (PAT) is often treated as a once-a-year chore. In reality, it is a practical maintenance system that helps you keep people safe, avoid downtime, and show that electrical risks are being managed sensibly.
For businesses, the legal duty sits under the Electricity at Work Regulations 1989: electrical equipment must be maintained so it does not present danger. PAT is one way to meet that duty, alongside good day-to-day checks and fixed-wiring inspections.
What PAT is (and what it isn’t)
PAT is focused on portable and movable electrical equipment. A simple rule works well in most workplaces: if it plugs into a socket outlet, it belongs on your PAT list. The aim is to catch damage and deterioration that can turn normal equipment into a shock or fire risk.
PAT is not a substitute for inspections of the building’s electrical installation. Fixed wiring, distribution boards, and hard-wired plant are normally covered by an Electrical Installation Condition Report (EICR) regime rather than PAT.
After a quick sense-check of what “portable” means in your premises, most businesses find the scope is larger than expected.
- IT equipment
- Break-room appliances
- Extension leads and multi-sockets
- Portable heaters and fans
- Chargers (tool chargers, laptop power supplies, radio chargers)
Start with an asset register you can actually maintain
A PAT programme stands or falls on the register. If items are missed, the testing schedule becomes a paper exercise. If the register is too complex, it will not be kept current.
A workable register normally records: item description, make/model (where helpful), location, a unique ID label, equipment class (Class I or Class II), and the next inspection date. Barcodes or QR labels help when you have multiple floors, multiple branches, or shared equipment.
If you want the simplest operational approach, organise the register by where the item lives rather than by who owns it. Premises-based lists make it easier for facilities teams, visiting contractors, and managers to coordinate access.
A practical “what needs testing” map for offices, shops, and warehouses
Different sites create different risks. Offices are usually clean, dry, and supervised, with equipment that is rarely moved. Shops introduce public access, display lighting, and frequent reconfiguration. Warehouses add dust, knocks, vehicle movement, higher powered equipment, and long cable runs that get dragged and pinched.
The table below gives a clear starting point for what to include, and what is normally outside PAT scope.
| Environment | Include in PAT (plug-in / cord-connected) | Common examples | Usually not PAT (fixed wiring regime) | Notes for a sensible schedule |
|---|---|---|---|---|
| Offices | IT, kitchen appliances, desk lamps, phone chargers, extension blocks, UPS units | PCs, monitors, printers, kettles, microwaves, power supplies | Fixed lighting, hard-wired hand driers, HVAC controls | Mostly lower risk. Many items are Class II (double-insulated), so visual checks carry a lot of value. |
| Shops | POS equipment, display lighting that plugs in, back-office appliances, portable tools, extension reels | Card terminals, label printers, portable spotlights, vacuums | Ceiling track lighting that is wired in, fixed signage supplies | Changes to layouts mean plugs and flexes get stressed. Keep an eye on multi-sockets and adapters. |
| Warehouses | Tools, chargers, portable lighting, cleaning machines, extension reels, heaters, break-room equipment | Drill chargers, floor scrubbers, portable floodlights, pallet truck chargers | Conveyors wired in, fixed racking lighting, hard-wired plant | Higher risk: equipment is moved, dropped, knocked, and used in harsher conditions. Shorter intervals often make sense. |
Class I, Class II, and why it changes your checklist
You do not need to be an electrical engineer to use the class system properly. You just need to recognise what it means for the test method.
Class I (earthed) equipment often has exposed metal parts and relies on an earth connection for safety. Think kettles with metal bodies, microwaves, many power tools, and some commercial equipment. Testing normally includes earth continuity and insulation resistance, along with a careful visual inspection.
Class II (double-insulated) equipment is designed so that exposed parts do not require an earth. It is often plastic-cased and marked with the double-square symbol. Testing usually focuses on visual inspection and insulation checks, not earth continuity.
This is one reason blanket “everything annually” approaches can be inefficient. A risk-based approach, like the HSE promotes, tends to put more attention on equipment that is earthed, heavily used, frequently moved, or used in harsher areas.
The PAT testing checklist, step by step
A strong checklist blends simple user behaviour with competent inspection and measured testing. It should also make it easy to quarantine failures quickly, before they become incidents.
When you write the checklist for your business, keep the language action-based, so it works for day-to-day use and for audits.
- Register and label: confirm the item is on the asset list, match the ID, and record its location
- User check: quick look before use, focusing on the lead, plug, and casing
- Formal visual inspection: unplug, then check plug wiring condition, cord grip, flex damage, signs of overheating, and correct fuse rating where applicable
- Electrical tests: apply the appropriate tests for the equipment class (earth continuity for Class I, insulation testing, polarity where relevant, and functional checks when safe)
- Record and control: log results, label pass or fail, remove failed items from service and route for repair or disposal
Competence matters here. Many workplaces sensibly train staff to carry out user checks and basic visual inspections, then use a competent person for combined inspection and testing. A NICEIC-accredited contractor is a common choice when you want clear competence, calibrated equipment, and a tidy, consistent reporting format.
Office checklist: what tends to get missed
Offices often have the highest volume of appliances and the lowest perceived risk. That combination is exactly why items slip through the net.
The most commonly overlooked office items are not the desktops, they are the “small electrics” that move between desks, meeting rooms, and homeworking setups. Laptop power supplies are a classic example: the transformer brick gets trodden on and the DC lead fails near the strain relief. Multi-socket extensions also deserve attention, especially when desks are reconfigured.
Break-room appliances deserve a tighter routine than IT. Heat, steam, crumbs, and cleaning chemicals are not kind to flexes and plugs. Where appliances are used near sinks, sensible RCD protection and safe positioning reduce risk, even before you get to testing.
Retail checklist: the public changes the risk profile
Shops operate in a more dynamic space. Displays are rearranged, seasonal equipment comes out of storage, and power is often taken from convenient outlets rather than well-planned distribution.
That makes cable management part of PAT success. A PAT label will not protect a flex that is regularly trapped under a display unit. Build in a quick check whenever displays move, and treat extension leads as test items in their own right, not as invisible accessories.
After a paragraph like that, it helps to keep a short “hotspot” reminder visible to staff who open and close the premises.
- Trip and trap points: flexes under mats, pinched behind shelving, crushed by display bases
- High-touch items: card terminals, phone chargers, handheld scanners
- Seasonal kit: portable lighting, fans, heaters, pop-up signage supplies
Warehouse checklist: higher power, harsher handling, shorter intervals
Warehouses and light industrial units are where risk-based scheduling proves its worth. Tools are used hard, chargers run for long periods, and equipment gets knocked. Dust and vibration accelerate wear. The result is simple: inspections need to be more frequent, and failed items need to be removed from use immediately.
Pay special attention to battery chargers for warehouse equipment. The equipment itself may be battery-operated, but the charger is a mains-powered appliance and sits firmly in PAT scope. Portable floodlights and extension reels are also frequent failure points because they are dragged, coiled, uncoiled, and used at the edge of their reach.
A useful operational discipline is to insist that extension reels are fully unwound during use. Coiled leads can overheat under load, and poor practice tends to show up as discolouration around plugs and sockets.
Choosing inspection and test frequencies without myths
There is no single legal PAT interval. The HSE is clear that the right frequency depends on equipment type, how it is used, and the environment. That is good news: you can build a schedule that puts effort where it reduces risk most.
A sensible pattern many businesses adopt looks like this:
- Low-risk office IT: longer intervals, with emphasis on visual inspection and good housekeeping
- Kitchens, heaters, and anything that gets hot: more frequent checks
- Warehouses, tools, extension reels: short cycles, with strong user checks supported by periodic formal testing
If you are starting from scratch, set initial intervals conservatively, then adjust based on what you find. A high pass rate across two cycles often justifies longer intervals for low-risk categories. Repeated failures in one category are a strong signal to shorten intervals or change equipment types.
Records, labels, and what auditors actually want to see
Records and pass labels are not always a strict legal requirement, but they are excellent management tools. They help you prove that a system exists, spot patterns, and show that failures were acted on.
Good records are also practical. When a site manager can pull up a list of failed items, repairs completed, and next due dates, PAT becomes part of normal operations rather than an annual scramble.
Digital systems make this easier at scale: scan an item, test, store results, and issue a report. Paper systems can work perfectly well too, as long as they stay current and someone owns the process.
Making PAT part of everyday safety culture
PAT works best when it is not treated as a standalone event. Build small habits that reduce electrical risk every day: keep leads off walkways, stop using damaged equipment immediately, avoid overloading multi-sockets, and report heat damage early.
For organisations that want a robust approach, pairing PAT with planned maintenance and periodic fixed-wiring inspections creates a clear, defensible safety programme. Contractors who work to recognised standards, keep equipment calibrated, and document results clearly can make that programme easier to run, especially across multiple sites and mixed environments.