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The Dangers of Carbon Monoxide
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What is Carbon Monoxide (CO)?

Carbon Monoxide (chemical symbol: CO) is a colourless, odourless, tasteless and toxic gas created by the incomplete combustion of fossil fuels (gas, oil, coal and wood), as used in our everyday appliances such as heaters, engines and boilers.

Why is Carbon Monoxide dangerous?

Having no colour, smell or taste means that it is very hard to detect. Inhaling carbon monoxide reduces the blood's ability to carry oxygen, leaving the body's organs and cells starved of oxygen. Each year, over 50 people die in the UK as a direct result of exposure to Carbon Monoxide Gas (CO). Many more people die through strokes and respiratory illness made worse by inhaling low levels of CO over prolonged periods. Still, more are left with permanent damage and invalidity.


The symptoms of mild Carbon Monoxide poisoning are similar to those of viral cold infections: headache, nausea, dizziness, sore throat and dry cough. More severe poisoning can result in a fast and irregular heart rate, over-breathing (hyperventilation), confusion, drowsiness and difficulty breathing. Ultimately it leads to coma and death.

Concentration of CO in the air Implications of Exposure
50 parts per million (ppm) Safety level as specified by the Health and Safety Executive for a maximum of 30 minutes.
200 PPM Slight headache within 2-3 hours.
400 PPM Frontal headache within 1-2 hours, becoming widespread in 3 hours.
800 PPM Dizziness, nausea, convulsions within 45 minutes, insensible in 2 hours.
Source From:

Effects of CO

The maximum level of Carbon Monoxide and Exposure Time that cannot be exceeded without causing illness:

Concentration of CO in the air Time of intake before illness
87 PPM 15 Minutes
52 PPM 30 Minutes
26 PPM 1 Hour
9 PPM 8 Hours
Source From: World Health Organisation

How to protect yourself and your family:

  1. Make sure rooms and heaters are well ventilated.
  2. Have your chimneys and flues checked regularly.
  3. Make sure boilers and heaters are maintained and serviced regularly.
  4. A Carbon Monoxide alarm will measure the concentration of Carbon Monoxide in a room and sound an alarm if the CO concentration is higher than permitted. Contact us to have one fitted.
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