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Chimney sweep Watford
Chimney sweeps - Solid fuel fires - Hertfordshire and Bedfordshire

Chimney Safety and Carbon Monoxide Poisoning

Carbon Monoxide Poisoning and Chimney Safety

Most people tend to associate the issue of carbon monoxide (CO) poisoning with gas appliances such as ovens and modern fires. However, a solid fuel stove or an open fire can still pose a serious threat to your health.

If you think that an open fire or a solid fuel stove could not put you in any danger of carbon monoxide poisoning, read on!

The simple fact is that blocked chimneys or flues allow carbon monoxide to seep back into your home and badly affect your health, it could even kill you.

How can carbon monoxide build-up be caused?

Open fires, stoves or oil boilers with chimneys or flues can cause problems if they fall into the criteria below:

  • un-swept for long periods of time
  • not swept properly
  • have cracks
  • are damaged in some other way
  • badly or incorrectly fitted
  • blocked

A badly fitted chimney pot will also cause back pressure and lead to very harmful fume emissions coming back into the room.

Some common causes of blocked chimneys:

  • there may be the remains of chimney fire debris
  • autumn leaves becoming impacted (happens a lot in bungalows)
  • birds nests are a common problem
  • building debris from repairs or renovations carried out on the property
  • Debris from climbing plants
  • spiders webs can catch other small debris that may build up to a critical level

Chimneys and flues allow carbon monoxide to get into the living space without you even knowing. Carbon monoxide has no smell, it has no colour so you won't even know it's there until it's too late.

Probably the only indication that carbon monoxide is present in the air will be that you or the members of your family will begin to feel unwell. The problem there is, there are so many other factors that can make people feel unwell. For example, if you feel sick shortly after eating some scampi that had a funny taste, you'll probably make the connection between the two. The scampi was a tangible thing that you could see, feel, taste and smell, carbon monoxide gives none of these clues. More worryingly, at higher concentrations carbon monoxide will cause you to go into a state of collapse and possibly even die.

The symptoms of carbon monoxide poisoning

Carbon monoxide poisoning symptoms can be very hard to recognize and diagnose. The symptoms differ from one person to the next and this even applies to individuals in the same household where carbon monoxide is present in high amounts.

The symptoms of carbon monoxide poisoning can be explained by many other common and minor conditions like cold, flu, tiredness, lack of sleep, food poisoning, or more serious conditions like heart problems.

So what are the symptoms of carbon monoxide poisoning?

  • Headaches
  • Nausea and or vomiting
  • Drowsiness
  • The sufferer could become rather light headed
  • A feeling of exhaustion
  • The sufferer may well get a sore throat
  • A dry cough is quite common
  • May even experience flu like symptoms
  • Chest palpitations
  • Chest pain
  • The sufferer could collapse
  • Unconsciousness could follow some of the above and death may well follow.

Young children and the old and infirm are at a greater risk than a healthy adult would be.

If you or any other people in the household are suffering from any of the above symptoms, you might be at risk of suffering from carbon monoxide poisoning.

It could happen to you!

As a chimney sweeping professional, I have heard some real horror stories. Only quite recently, a client telephoned to thank me and to say that his wifes overall health had improved significantly in the weeks that had followed my visit to sweep their chimney. She had been prone to bouts of nausea that were usually accompanied by headaches and an uncontrollable tiredness. They had many tests done at the doctors but to no avail. They were aware that her symptoms only manifested themself when she had settled into the front room at night to watch her favourite soap operas. The husband would usually disappear out to the sanctity of his potting shed so was unaffected.

Whilst at the property I found a rather large accumulation of leaves, grass and twigs, clearly placed there by birds. I carried out a thorough clean and smoke test and declared the chimney fit for purpose. No wonder she felt that way! There was no doubt in my mind that she had been suffering from carbon monoxide poisoning. It could have been so much worse!

Action to take if you think carbon monoxide may be affecting your health.

  • Stop using the appliance at once. (Turn gas off at the isolator valve if it is a gas operated appliance)
  • Get as many windows and doors open as possible to ventilate the whole area
  • If it is gas powered, call the emergency service applicable to that type of appliance
  • It is very important to get the chimney or flue cleaned and checked as quickly as possible.
  • Get all the appliances tested to ensure everything is safe
  • Get a carbon monoxide detector alarm installed as soon as possible
  • Have your blood or breath tested within 4 hours of the suspected exposure to the coarbon monoxide.

The final action in the list above may sound a little strange to some people but it is very important to get this one right. You may need to be quite forceful with your healthcare professional to get them to do the right tests. This is because a blood or breath test can come back as falsely negative. If the sufferer has been out in the open air or sitting in a waiting room for some time, the levels of carbon monoxide in the body can drop below detectable levels so it is vital to have the test done within four hours of being in the affected area.

Further information

If you would like to know more or are interested in a quote we would be happy to help. Phone us on 01923 661 614, email us at or fill in our free quote form and we will be in touch as soon as possible.

Ansell Chimneys

t: 01923 661 614

m: 07941 282 325


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