A PLUMBER died after being electrocuted as he carried out work at his boss’ home, an inquest heard.

Lukasz Sobala, 36, was electrocuted as he installed copper piping on the outside of The Bungalows in Chartridge at about 5pm on August 23.

Andrew Pitt, an electrical systems expert from the Health and Safety Executive, told the inquest an earth fault in the kitchen ring main circuit caused the voltage to shoot up in the main earth terminal.

This resulted in all the connected conducting material attached to the terminal - including the boiler and piping which Mr Sobala from Moulder Court in Chesham was working on - becoming live.

The Residual Currant Device (RCD) on the consumer unit was also defective and failed to trip, allowing the current to continue to flow.

The inquest at Beaconsfield Coroner’s Court was told Mr Sobala and Aron Wiezchowski, both originally from Poland, had been relocating the boiler in the house before Gas Safe-registered fitter Dean Maggs came round to install it.

The copper pipe was not connected to the meter box but it was connected to the boiler which was switched off at the mains.

The HSE investigators were unable to locate exactly where the electric fault occurred but said anyone that made contact with copper and ‘true earth’ at the property at that time of the fault would have been at risk.

A jury decided upon a narrative verdict after about 30 minutes of deliberation. It read: “Lukasz Sobala was installing copper pipework on the exterior of the building.

“At some stage, a fundamental earth fault in the kitchen ring main circuit occurred resulting in a voltage rise of the main earth terminal.

“This caused the voltage to rise on all items of conducting materials attached to the terminal, making the boiler and copper pipework live.

“Mr Sobala, whilst holding the copper pipe and due to contact with the ground, was electrocuted.

“The RCD on the Consumer Unit should have tripped, stopping current flow, but it was defective and failed to operate.”