UP to 250,000 gas appliances are fitted illegally in Britain every year, a report warns today – killing about 50 people through carbon monoxide poisoning.

Meanwhile, 4,000 people end up in hospital every year after breathing in poisonous fumes in the home, a committee of MPs has revealed.

Yet, only one in seven homes is fitted with a carbon monoxide (CO) alarm to alert householders to the danger – despite the devices costing as little as £15.

Now the Commons Local Government Committee has urged ministers to take action, by:

• Requiring audible, wired-up alarms to be installed with new heating appliances in all new – or existing – homes;

• Cracking down on the installation of gas appliances by rogue fitters, not registered as competent engineers;

• Launching a high-profile publicity campaign, to ensure householders know the legal and safety consequences of not choosing a “Gas Safe” engineer;

• Reporting back to the committee within two years on the effectiveness of the measures.

The report, published today, concludes: “We are clear that too little is still known by the public about the risk of the odourless, invisible and potentially-lethal fumes of carbon monoxide.”

The Northern Echo launched its Silent Killer campaign following the case of County Durham student Anne Brennan, 19, from Houghton-le-Spring, who died in Durham City accommodation in 1995.

An inquest ruled she was unlawfully killed and her landlord was fined £10,000 for failing to ensure the boiler in the property was properly maintained.

The call for a publicity campaign echoes repeated criticism of Labour during its years in office, when ministers were also accused of failing to spend money on better public information.

Despite that, there appeared to be evidence that fewer lives were being lost to CO poisoning – with fatalities down to below 20 each year.

However, today’s report questions that estimate, pointing to evidence of “undiagnosed or misdiagnosed exposure” over a prolong period – which might push the number of annual tragedies to 50.

It quotes the group CO-Gas Safety, arguing: “As there is no automatic testing on dead bodies for CO, it is impossible to ascertain the true number of deaths from CO.”

At present, a carbon monoxide alarm is only legally required where there is a solid fuel heat source, which are ten times more likely than gas to generate CO emissions.

The inquiry was launched because the Department for Communities and Local Government is reviewing building regulations for gas and electricity appliances.