Electricians liability insurance holders have been warned about carrying out safety checks after the prosecution of a firm.
Graeme W Cheyne (Builders), of Sugarhouse Lane, Aberdeen, pleaded guilty to failing to provide and maintain a safe system of work for employees working on or near an electrical system, breaching Section 2(1) of the Health and Safety at Work Act 1974. It was fined £9,000 with additional costs of £4,000.
Aberdeen Sherriff Court heard that George Forbes, 62, of Aberdeen, was working for Graeme W Cheyne (Builders) on a block of flats in Holburn Street when he attempted to move a redundant electricity power supply.
However, the fuse-cut out was still live and connected to a 415 volt cable when he touched it.
It then localised an electrical explosion and set the joiner's boilersuit on fire.
Liz Standen, Health and Safety Executive inspector, said: "It is extremely dangerous to make assumptions that electrical equipment is safe to work with."
Earlier this month, installers, designers and maintenance firms were given a warning about the dangers of electric gates, after the recent deaths of two children.