Arc Fault Detection Device (AFDD)

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Arc Fault Detection Devices protect against fires caused by arc fault currents in final circuits of fixed installations. An arc fault is a high power discharge of electricity between two or more conductors which generates heat. This heat can break down the wire’s insulation and cause an electrical fire. AFDDs protect against arc faults, as they automatically trip a circuit when electric arcs are detected. FDDs are protective devices installed in consumer units to provide protection. They analyse waveforms of electricity to detect arcs on the circuit. The power is then cut off to the affected circuit, preventing a fire. 


Over 50% of accidental domestic fires in the UK are caused by electrical products being misused or experiencing faults. The amount of electrical equipment in the average home is growing, bringing further risk of electrical fires. Electrical fires caused by arc faults typically occur at loose connections, poor terminations, in damaged leads and cables, or through old, weak and failing insulation. The majority of incidents are preventable through simple precautionary measures such as installing an RCD in your fuse box. This life-saving device switches the electricity off automatically if there is a fault. We recommend keeping belongings away from your fuse box and electricity metre, never plugging in too many appliances in the same socket and checking cables for any damage before using appliances. 


Homeowners should have their electrical installations checked by a registered electrician every ten years, or on moving house. For rented properties, Landlords should have their properties checked every five years, or on change of tenancy. See our dedicated page for more information on Landlord responsibilities.