A West Yorkshire green energy firm and a solar installer have been prosecuted for safety breaches after a labourer was severely injured when he fell around 20ft from a roof in Huddersfield.

The 27-year-old worker, who had no experience of installing solar panels, lost his footing when rain began to fall while he was on a barn roof in Lepton. He slipped onto his back and went sliding down the roof. He tried to grab a bracket but failed to get a grip and slid feet first over the edge.

The man from Leeds landed in bushes below and broke seven ribs, his collarbone and suffered a bruised lung. He has since returned to work.

The incident on June 27, 2013, was investigated by the Health and Safety Executive (HSE), which identified serious safety failings by Peter King, trading as Kingson Roofing, Building and Construction, of Ossett, and Investment Renewables Ltd, of Wakefield.

Kirklees Magistrates heard that Mr King was subcontracted by Investment Renewables to install 56 solar panels on the barn roof. He was one of three men working on the installation though only one had any experience.

The workers used a four-lift tower scaffold to reach the sheet metal pitched roof and had installed 13 of the panels when it started to rain. The labourer lost his footing on the wet surface shortly after and slid over the edge as there were no safety measures in place to prevent or mitigate falls.

HSE found Investment Renewables had not adequately assessed the risks arising from the solar panel roof installation and had also failed to ensure its sub-contractor, Mr King, had done so.

As a result, no safe system was in place for the work itself and neither of the defendants had provided or arranged for edge protection to be installed to guard against roof falls.

In addition, Investment Renewables had not supervised the work to ensure their sub-contractor was operating safely. Peter King hadn’t planned the job, didn’t provide the right equipment and hadn’t trained two of his workers properly.

Investment Renewables Ltd, of Wakefield Road, Grange Moor, Wakefield, was fined £14,000 and ordered to pay £404 in costs after admitting breaching the Health and Safety at Work etc Act 1974.

Peter King, Kingson Roofing, Building and Construction, of Wesley Street, Ossett, Wakefield, was fined £10,000, also with £404 to pay in costs, for a breach of the same Act.

After the hearing, HSE inspector Andy Denison said: “This worker’s fall and his subsequent painful injuries could easily have been prevented had basic safety precautions been put in place. Each party failed in its responsibilities to protect the workers from danger by assessing risks and providing a safe system of work.

“Mr King had obviously not planned the job thoroughly. He had only looked at a photo of the building and not even visited the site. Investment Renewables also failed to make sure the work was safely planned and did not supervise it.

“Despite clear guidance from HSE and the solar panel industry, companies continue to work on roofs without suitable precautions, posing an entirely unacceptable risk of serious injury, or even death, to employees.”