Alex's mother found her dead on her return from work

The mother of a teenager from Cwmbran, Torfaen, who died in her bedroom in 2005, said not enough was known about carbon monoxide dangers in the home.

The CO Gas Safety campaign told BBC Wales' Eye on Wales that the industry should pay for mainstream TV adverts.

The Energy Retail Association said it was spending "millions" on campaigning.

Anne Mitchell said that she knew little about the dangers of carbon monoxide, when her 14-year-old daughter Alex died in March 2005.

She was overcome by fumes from a faulty fire, installed only three months earlier.

The man who fitted the fire was not qualified. He later admitted manslaughter and was jailed for two years last October.

We've already risen to the challenge and achieved a target of reducing the number of fatal incidents by a minimum of 20% by 2010 Energy Retail Association

"You'd heard of it, but it always happens to someone else," said Mrs Mitchell.

"There wasn't any information available that was given to me by the installer; the fitter never ever mentioned carbon monoxide at any time or told me of any dangers. Had he done or said 'get an alarm', Alex would still be here."

On the day Alex died, she had been at home alone with the family's pet dog and they were found when Mrs Mitchell returned home from work.

At the time, the Health and Safety Executive (HSE) said the case proved the dangers posed by faulty or incorrectly fitted or tested gas appliances.

Official figures suggest that every year in the UK, between 20 and 30 people are killed by fumes leaking from faulty home gas appliances.

The HSE has undertaken a year-long review of gas safety and its recommendations are awaiting ministerial approval.

The review included a survey of 600 homes by Dr Ben Croxford of University College, London.

He found that one in five of all homes with gas had a problem appliance - usually a fire or cooker.

While the fieldwork was carried out in London, Dr Croxford told BBC Wales that it was "common sense" that the figure was likely to be as bad in Wales.

TELL-TALE SIGNS ON APPLIANCES Yellow or orange flames, unless fuel-effect fire Soot or stains around the appliance A pilot light that frequently blows out Source: HSE

Stephanie Trotter, director of campaign group CO Gas Safety, said the industry should finance network TV adverts to raise public awareness.

She criticised the winter advertising campaign only being run on cable and satellite channels and said it needed a profile, similar to anti-smoking and anti-drink driving campaigns.

Ms Trotter said: "We have a very wealthy fuel industry. Why isn't the government forcing the companies to provide the money by imposing a mandatory levy - or the government could provide the money itself?"

The Energy Retail Association defended its members' safety record.

A spokesman said: "We've already risen to the challenge and achieved a target of reducing the number of fatal incidents by a minimum of 20% by 2010.

"We're spending millions on campaign activity, putting leaflets through people's doors and particularly targeting people who are very vulnerable.

"But people must realise that they must make sure when they're having their appliances checked that it's being done by a registered Corgi fitter."