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Carbon monoxide safety tips

Carbon monoxide leaks can lead to carbon monoxide poisoning, which can be fatal. You need to know how to prevent leaks and what to look out for in the event that a leak occurs in your home. Read on to find out how.
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Carbon monoxide detector

Carbon monoxide poisoning poses a danger to any household. The good news is that you don’t have to worry about becoming a victim if you use a carbon monoxide detector or carbon monoxide alarm. You may even be able to get a free carbon monoxide detector from your gas supplier.

In this guide, we'll reveal what carbon monoxide is, what the signs of carbon monoxide poisoning are, what you can do to detect it, and how you can prevent it from happening in the first place.

What is carbon monoxide?

Carbon monoxide is produced when there's not enough oxygen to bond with carbon-producing compounds. It occurs naturally, but more often in enclosed spaces like your home. One of the sources of carbon monoxide is faulty gas appliances like heaters, boilers and fireplaces; another is if chimney flues or vents become blocked.

Carbon monoxide can also be produced by burning oil, wood, petrol and coal.

How dangerous is carbon monoxide?

Carbon monoxide poisoning is extremely dangerous. It can’t be seen, heard, smelt or tasted, which is why it’s referred to as the ‘silent killer’. 

According to Statista, deaths rise during the colder months of the year, peaking in December when more people have their heating on. NICE reports that there are approximately 40 deaths, 200 non-fatal poisonings requiring hospital admission and 4,000 admissions to A&E from carbon monoxide poisoning each year. However, as NICE says, "The true incidence of carbon monoxide poisoning is likely to be significantly higher because low-level carbon monoxide toxicity is easily misdiagnosed as the signs and symptoms are often non-specific, and may simulate other more common conditions, such as flu-like illness, food poisoning, or depression."

If you would like to know more about making sure your home is 'gas safe', consult our list of gas safety tips.

What are the signs of carbon monoxide poisoning?

As a colourless and odourless gas, carbon monoxide is difficult to detect, but there are several clear symptoms that indicate carbon monoxide danger. The six main symptoms as identified by the Gas Safe Register are:

  • headaches

  • dizziness

  • breathlessness

  • nausea

  • collapse

  • loss of consciousness.

While you could suffer any of these symptoms for a variety of reasons, if your family and pets are afflicted by these flu-like symptoms in your home, but the symptoms mysteriously vanish when you leave it, you may be feeling the effects of carbon monoxide poisoning.

What to do in case of an emergency?

If you start to notice these symptoms you should open doors and windows, turn off any gas appliances and leave your home.

If you're feeling the effects of carbon monoxide poisoning, either call an ambulance or get yourself to hospital. If you suspect there is a gas or carbon monoxide leak in your home, call the Gas Emergency Helpline on 0800 111 999 to report it. Find out more about dealing with gas leaks here.

Do you need a carbon monoxide detector?

Every home should be fitted with at least one carbon monoxide alarm. Carbon monoxide detectors could save your life as they’re designed to sound an alarm before carbon monoxide levels in your home reach dangerous concentrations.

If the alarm on your carbon monoxide detector sounds, turn off any gas appliances, leave your home immediately and contact an engineer.

A carbon monoxide monitor is cheap to buy and easy to install, and you may even be able to get a free carbon monoxide detector from your gas supplier.

These small devices look similar to a smoke alarm, and cost between £15 and £35 from most reputable DIY stores.

Make sure you get an audible alarm rather than those that give visible warnings, or 'black spot' alarms, as you are most at risk from carbon monoxide poisoning while you sleep.

When you buy your alarm, make sure it has the British Standard EN50291 mark (also shown as BSEN 50291) and look for the British Standards Kitemark or the equivalent from other European standards associations.

How to install your carbon monoxide alarm

When you install your alarm, make sure you put it in a central location like the hallway, place it at head height, and make sure it’s at least a metre from any appliances.

The golden rule, as with smoke alarms, is to test it regularly and replace the batteries at least once a year, or when the low battery alarm sounds.

How can you prevent carbon monoxide leaks in your home?

The key to preventing carbon monoxide is regular maintenance of your appliances. First, check your appliances for the Gas Safe Register's tell-tale signs:

  • Your cooker flames should be strong and blue, not weak and yellow or orange.

  • Watch out for soot or yellow-brown staining around or on appliances.

  • Your boiler pilot light should be constant and not blow out.

  • Look out for increased levels of condensation on the inside of your windows.

If you notice any of these signs on your boiler or oven, turn it off immediately and call in an accredited engineer.

You should also make sure your boiler and gas appliances are regularly maintained (at least on an annual basis) by a Gas Safe Registered engineer. The Gas Safe Register, previously known as CORGI, is the UK's gas safety body.

Just look out for the Gas Safe Register logo — a yellow triangle — on your engineer's registration card. If you're in any doubt, check on the Gas Safe Register website or call 0800 408 5500.

The same principle applies when you're having appliances installed in your home. Always make sure your installer is Gas Safe Registered-accredited or look for HETAS accreditation if you’re having any sold-fuel appliances installed or serviced.

Other things you should do to avoid potential carbon monoxide poisoning include not leaving your car engine running in your garage (even with the garage door open). When using a barbeque grill, always use it out of doors away from your windows and doors. If cold, avoid relying on your gas cooker to warm your home.

Finally, perform regular inspections of any ventilation ducts or shafts, such as those for your cooker or tumble dryer, to ensure they’re not blocked by dust or debris.