The Health and Safety Executive (HSE) has highlighted how vital plumbing courses are for certain procedures after a tradesman was sent to jail for carrying out work while under-qualified.
Toni Drury, an HSE inspector, explained that John Carslake - trading as Aqua Plumbing - ignored a prohibition notice preventing him from working on gas appliances and was caught in the act by the BBC's Rogue Traders programme.
Ms Drury described how working on such equipment involves specialised knowledge that must be gained from plumbing courses before an individual can safely undertake certain maintenance and repair work.
"They are not only putting themselves at risk of prosecution and a large fine, they are also putting their customers' lives at risk," she added.
Mr Carslake has been sentenced to a six-month term in jail.
North-west plumber Alan Carl recently told the Manchester Evening News that he earned "a fortune" over the Christmas period, due to the number of burst pipes caused by the cold weather.
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