Mrs Carney, 81, was saved after the Telecare equipment detected the deadly gas in her home and automatically raised the alarm.

Carbon monoxide is commonly known as the 'silent killer' as it is not only colourless but also odourless and tasteless meaning potential victims can be completely unaware of its presence.

Mrs Scott, Mrs Carney's niece, said the story could have turned out completely differently had it not been for the detector.

"It was frightening to think what might have happened, as my aunt had been sleeping downstairs next to the kitchen at the time because her stairlift had broken," she said.

The equipment, which is provided by Notts County Council in partnership with A1 Housing and Bassetlaw Council, automatically informed the control centre of the gas leak, which was coming from a faulty cooker.

Mrs Carney and her niece were immediately warned of the dangers and advised to open all windows and doors to allow the gas to escape, while an A1 Housing warden attended the scene to offer support.

The Safe At Home Telecare system monitors the safety of vulnerable people in their own homes by providing a range of lifelines such as fire and carbon monoxide detectors.

It also offers a range of more advanced devices which alert the contact centre if a person has a blackout or becomes unwell and unable to move.

Coun Alan Rhodes, cabinet member for adult services and health, said the security system enabled older people to stay more independent for longer, offering their relatives and carers much-needed reassurance. "When we launched the system late last year, we said it could help save lives - and it has already proved its worth," he told the Guardian. "We are really pleased that Mrs Carney is ok after her frightening experience."

The Telecare system is currently available to older residents as part of the community alarm systems run in Bassetlaw, Mansfield and Sherwood, regardless of whether they live in a council home or not.

It is anticipated that over 1,900 older people with differing needs and disabilities across Notts will soon benefit from the service.

There is a small weekly charge for the Telecare service, on top of the lifeline service which costs approximately £3 per week.

Anyone wishing to find out further information about Telecare can contact the A1 Housing Supported Warden Service on 01909 533192.