Class I Equipment
Uses basic insulation and a protective earth connection.
- Usually fitted with an earth conductor
- May include metal-cased equipment
- Earth continuity testing may be appropriate
- Insulation or leakage testing may also be used
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Electrical Equipment Testing
Electrical PAT Testing Explained Clearly
Professional inspection and electrical testing for workplace appliances, carried out according to the equipment type, construction class and level of risk.
✓Class I and Class II equipment✓Visual and electrical checks✓Commercial premises
ⅠClass I EquipmentProtection relies on a protective earth
ⅡClass II EquipmentDouble or reinforced insulation
ⅢClass III EquipmentLow-voltage equipment
⚡Risk-Based TestingChecks selected for the equipment and use
Understanding the Service
What Is an Electrical PAT Test?
An electrical PAT test is a combined inspection and, where appropriate, electrical test used to help assess whether an appliance remains safe for continued use.
The engineer first considers the equipment construction, its condition and how it is used. This determines which checks are relevant rather than applying exactly the same test to every item.
A formal visual inspection may identify damaged plugs, worn cables, cracked casings, signs of overheating or unsuitable repairs.
Important informationAn appliance without a readable rating plate should not automatically be disposed of. It should be assessed by a competent person and removed from use only where its safety cannot be established.
Equipment Construction
Understanding Appliance Classes
The equipment class describes how protection against electric shock is provided and helps determine which tests are suitable.
Class II Equipment
Uses double or reinforced insulation and does not rely on a protective earth.
- Normally identified by the double-square symbol
- Does not require an earth continuity test
- Visual inspection remains important
- Suitable insulation or leakage tests may be used
Class III Equipment
Protected by operating at separated extra-low voltage.
- Operates from a low-voltage supply
- The mains adaptor may still need assessment
- Visual inspection can identify damage
- Testing depends on the supply arrangement
Checks and Measurements
Tests That May Be Carried Out
Not every appliance requires every test. The engineer selects checks suitable for the equipment.
Formal Visual Inspection
Checks the plug, fuse, cable, casing, strain relief and visible condition.
Earth Continuity
For suitable Class I equipment, checks the protective earth path.
Insulation Resistance
Assesses insulation between live parts and accessible surfaces.
Leakage Current
May be used to assess current flowing through protective or accessible paths.
Lead and Polarity Checks
Checks suitable leads for wiring, continuity and insulation.
Functional Check
Where appropriate and safe, confirms normal basic operation.
Equipment Movement and Use
Common Equipment Categories
How often equipment is moved, handled or exposed to damage can influence inspection frequency.
Stationary Equipment
Normally fixed in position or not usually moved during use.
Movable Equipment
May be moved between locations but is not normally carried during use.
Portable Equipment
Can be moved while connected or readily carried between locations.
Hand-Held Equipment
Intended to be held during normal use and more exposed to wear or impact.
How the Visit Works
A Clear Four-Step Process
Identify the Appliance
The equipment, rating information and construction class are reviewed.
Inspect Its Condition
The plug, cable, casing and visible components are checked.
Complete Suitable Tests
Relevant electrical tests are selected for the equipment.
Record the Result
Passes, failures and observations are documented.
Common Questions
Electrical PAT Test FAQs
Does every appliance need an electrical test?+
No. The appropriate action depends on the equipment, its class, condition, use and level of risk.
What happens if the rating plate is missing?+
The equipment should be assessed by a competent person and removed from use where its safety cannot be established.
Does Class II equipment need an earth test?+
No. Class II equipment does not rely on a protective earth conductor.
How often should equipment be tested?+
There is no universal fixed interval. Frequency should reflect use, environment, likelihood of damage and previous results.
What should happen to failed equipment?+
Unsafe equipment should be removed from use and then repaired by a competent person or replaced.
Request a Quote
Arrange Professional Electrical PAT Testing
Tell us your location, premises type and approximate appliance quantity. Our team will provide a straightforward quotation.