The 41-year-old of Oakenshaw, County Durham, was installing metal fencing as part of the refurbishment of the car park of Northgate Vehicle Sales Ltd in Darlington when he hit the cable in November 2010.

Darlington Magistrates’ Court heard that the installation of the fencing required the worker to dig holes in the ground to insert the base of each fence post.

He was incorrectly told by the main contractor that there were no buried electricity cables.

While using a ground breaker, the tool’s tip pierced through one of two 11kV cables buried around 80cm underground, causing a short circuit that released at least one million watts of energy.

This vaporised the breaker’s tip in a cloud of flame and molten metal, causing severe burns of varying depths to his arms and some burns to his face and neck.

The court was told Northgate Vehicle Sales Ltd had not provided the relevant information about the site to the contractor before work started.

Northgate Vehicle Sales Ltd pleaded guilty to breaching the Construction (Design and Management) Regulations and was fined £12,000. The company was also ordered to pay £6,123.55 costs.

After the hearing, HSE inspector Jonathan Wills said:  “The injuries sustained by the worker could have easily resulted in him losing his life.

“He suffered severe burns and is still recovering from those injuries following an incident that could have been avoided had Northgate Vehicle Sales Ltd requested service plans and given them to those carrying out the construction work.

“The risk of striking underground cables is well known throughout the construction industry and the law says you must take precautions to avoid danger.

“There is a wealth of guidance available for contractors and the clients for whom the work is being carried out to help them manage the risks effectively.”