UK households forced to 'evacuate' home if they hear this sound during snow

UK households have been warned they should move to fresh air and get out of the house in this week's cold snap - if they hear four noises from their carbon monoxide detectors. Almost 27million people risk carbon monoxide poisoning by not having an alarm in their homes.

But even those who do have them fitted are at risk from the dreaded four beeps and pause. First Alert warned: "4 Beeps and a Pause: EMERGENCY. This means that carbon monoxide has been detected in the area, you should move to fresh air and call 9-1-1."

The warning comes as more and more fires and boilers are lit up this week, with the country set to suffer from -2C lows in England, and the mercury dropping to even lower - with predicted -10C temperatures north of the border in Scotland.

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CO Be Alarmed! s pokesman Lawrence Slade said: “As we enter one of the coldest months of the year, it is worrying to think that over half of the population are not protecting themselves from carbon monoxide poisoning. This is a silent killer - you cannot see it, taste it or smell it."

“Protect yourself, and your family, by following the simple ABC checklist – do you have an alarm fitted? Have you tested it and are the batteries working? Have you had an up to date gas check?” More than 50 people die each year from carbon monoxide poisoning and another 4,000 are treated in hospital.

Essex fire service live safe manager Claire Monk said: "Carbon monoxide poisoning is potentially fatal and even inhaling low levels of the gas can cause lasting damage to your health. That's why it's important that we support and raise awareness during Gas Safety Week to educate our communities on how to maintain their gas appliances in their homes and understand the signs and symptoms of carbon monoxide poisoning if a gas appliance becomes faulty at any time.

"We offer free carbon monoxide alarms to vulnerable residents in Essex. If you are a vulnerable resident or know someone who is, please get in touch by booking a home safety visit."