The warning follows the HSE’s prosecution of two companies based in Hertfordshire and Hackney after a worker suffered a serious head injury when he fell approximately 2.2 metres.

Team Q Maintenance Limited of New River Trading Estate, Chestnut, Hertfordshire and Schawk UK Limited, of Shepherdess Walk, Hackney, were each fined £20,000 and ordered to pay costs of £3,098 at City of London Magistrates Court.

Team Q Maintenance Ltd was found guilty of breaching section 2(1) of the Health and Safety at Work Act 1974 and Schawk UK Limited was found guilty of breaching Regulation 3(1)(a)(b) of the Management of Health and Safety at Work Regulations 1999.

On July 15 2005, Mr Kantilal Mistry from Stanmore, Brent, an employee of Team Q Maintenance, fell approximately 2.2 metres while carrying out repairs on air conditioning units at the premises of Schawk UK Limited. There were no fixed means of access or edge protection to prevent falls.

Mr Mistry borrowed a step ladder from Schawk UK to access the roof which was not suitable nor safe for the task. He suffered a serious head injury which has left him with ongoing health problems and unable to work.

Following the prosecution, HSE inspector Chris Tilley said: “Both defendants were aware of the risks of working at height which had been clearly identified at least a month before the incident, but this information had not been supplied to Mr Mistry.”

He added: “No effort was made to ensure that Mr Mistry was supplied with safe access equipment or to prevent him from working. If this information had been acted upon, Mr Mistry would not have been injured.”

Tilley also highlighted a number of options available to ensure that safe access could have been achieved which would have greatly reduced the risk. “Precautions to prevent falls are often simple and there is free guidance readily available to help employers take the right action,” he concluded.