PAT Testing in NR5

Portable appliance testing (PAT) is the inspection and testing of equipment that plugs in. The law behind it is the Electricity at Work Regulations 1989, which require electrical equipment with the potential to cause injury to be maintained in a safe condition. The Regulations set no frequency and do not require annual testing. HSE states this directly, and calls annual testing of everything in a low-risk office a myth.

The work runs in three tiers, and most sites need all three:

• User checks by whoever picks the item up. Nothing recorded.
• Formal visual inspection of the plug, fuse rating, flex, cord grip and casing, looking for damage and signs of overheating.
• Combined inspection and test using instruments: earth continuity on Class I equipment, insulation resistance, polarity of the lead and a functional check.

Intervals come out of risk, not a calendar. A 110V transformer and power tools on a building site need looking at far more often than a desk lamp. Construction class, environment, how often the item is moved and its fault history all feed into it.