Preston Crown Court heard that on November 22 2013 John Flowers, 63, who was an experienced lineman, climbed a ladder resting against a wood pole in order to trim ivy away from the power lines.

It is believed that Flowers somehow cut through his work positioning strap and fell to his death.

The court heard that the work of trimming the ivy off the pole was not identified as short duration work and was not suitable to be undertaken working from a ladder.

The company failed to properly plan the work; no provision was made for the use of a mobile elevated work platform to undertake the task.

An HSE investigation found the work had not been properly planned. The ivy growing onto the electricity conductors was first identified some five years before the accident and then again in June 2013.

A survey of the vegetation clearance work which was required was undertaken six weeks prior to the incident.

But none of this information was given to any of the linemen and they were not provided with information on how the work was to be carried out.

Electricity North West Limited of Warrington was found guilty of breaching Work at Height Regulations and was fined £900,000 with costs to be agreed at a later date.

Speaking after the hearing HSE inspector Rose Leese-Weller said: “Electricity North West failed to ensure that working at height was properly planned, appropriately supervised and carried out in a manner that was safe.

“Had these steps been taken we may not have had this tragic outcome.”

Electricity North West said: “The Company was found not guilty of charges relating to failure to risk assess and failure to ensure the safety of its employees.

“It has been exonerated in respect of its underlying health and safety management but was found guilty of a technical failing to adequately manage work at height.

“The Company are reflecting on today’s sentence and are considering their options, which may include an appeal against the single guilty verdict.”

Chief Executive Peter Emery said: “John was a valued colleague with over 30 years’ service to the Company.  His death was a tragic loss to his family and to his colleagues.  We were devastated by his loss.

“Working at height with electricity brings unique risk and safety is a continuous challenge.

“In finding us not guilty on two charges, the jury recognised the effectiveness of our risk assessment process and our compliance with the Health and Safety at Work Act through our safe systems of work.”

He added: “We’ll continue to work hard to make the job John loved as safe as possible.”