The Gas Safe Register has said that tradesmen must complete the appropriate gas training courses before carrying out gas work.

Research by the organisation revealed that illegal gas fitters, who have not completed the necessary accredited gas training courses or commercial gas courses, do 250,000 jobs in British homes each year.

Gas Safe Register's Regional Investigation Officer for Scotland Keith McKinlay said that engineers who carry out gas work may not be aware that they are not qualified to do so.

He added: "Not everyone realises that different types of gas work require different qualifications. Just because someone is qualified and registered to work on one gas appliance, for example gas boilers, does not mean that they are automatically qualified to put in a gas fire."

Mr McKinlay went on to say that it is essential that homeowners' check that engineers have passed approved gas training courses and are on the Gas Safe Register before they allow them to undertake work on their property.

If an unqualified person, who has not completed the appropriate gas training courses or commercial gas courses, attempts gas work the consequences could be fatal, according to Mr McKinlay.

He said: "If they do this, the work is illegal and potentially life threatening. The work that your gas engineer can do safely is listed on the back of their Gas Safe Register ID card. It's really important to check the list on the back of their cards every time you have gas work done."

Mr and Mrs Sood from Glasgow failed to follow the advice from Gas Safe Register and fell victim to a local gas fitter who installed their boiler illegally despite claiming he was registered.

The fitter, who had even been recommended to the family by a friend, was not on the Gas Safe Register and following an investigation by the organisation it was deemed that the Sood's boiler was at risk and had to be turned off immediately.

Mrs Sood said: "I'm now left with an unusable boiler and we've had to go through one of the coldest winters in 30 years with no heating or hot water. It's been dreadful. We're also £2,000 out of pocket and it will cost us an extra £3,000 to have it fixed which we just can't afford to pay."

People interested in gas training courses should aim to achieve the CITB Intermediate Gas Certificate because it will ensure that the student has knowledge of changes to legislation, British Standards and industry best practice.

Those already in the gas industry may be keen on commercial gas courses which provide people with the knowledge and understanding required to undertake formal ACS assessments.