Published: 00:01, 08 September 2016
It is invisible, tasteless, odourless and potentially deadly - and more people are succumbing to its effects in Kent.
Figures show cases of carbon monoxide poisoning - also known as the silent killer - have more than doubled in the county in the past two years.
Data released following freedom of information requests to Kent NHS trusts reveals the number of people attending Kent's A&E departments after inhaling CO gas has risen by 220% - with cases affecting children rocketing by 1000%.
The figures, obtained by campaign group Project SHOUT, measured recorded cases year-on-year from July 2014 to June 2016.
There were 32 suspected incidents from 2015 to 2016, compared to 10 the previous year.
They include six-year-old Aaden-James Mann, who was taken to hospital with headaches, dizziness, lethargy and vomiting earlier this year.
He was found to have breathed in carbon monoxide, thought to have come from a faulty boiler at his Chatham home.
And last year, a Tonbridge family were lucky not to have suffered poisoning after a gas leak from their cooker was ignited by flames from the hob, causing a house fire.
Earlier, in 2014, 61-year-old Linda Frost died after an unqualified friend fitted a "dangerous" bathroom boiler at her Leysdown chalet, which emitted toxic fumes.
Terry Blackwell was later cleared of gross negligence manslaughter in connection with the death, but convicted of two offences of contravening Health and Safety regulations.
Project SHOUT is now urging people to protect themselves by fitting carbon monoxide alarms in their homes.
Rob Lyon, campaign director for Project SHOUT, said: "These numbers are very concerning, particularly the rise in cases amongst the most vulnerable, namely children and the elderly.
"Carbon monoxide poisoning can only be detected by an alarm as you can't see, smell or taste it.
"Children and older people are particularly at risk because their bodies are more susceptible and in the case of some older people, are less likely to keep their appliances serviced."
Nationally, there was a 10% rise in recorded incidents of suspected CO poisoning, with cases in children up by 20% and cases among the over 60s increasing by 17%.
Carbon monoxide is emitted when fuel does not burn properly and can be caused when an appliance is incorrectly fitted or poorly maintained.
Common causes of carbon monoxide poisoning include gas fires, cookers and boilers, open fires and log burners, BBQs and oil heaters.
In October 2015, legislation came into force that required private landlords to fit a carbon monoxide alarm in every property that had a solid fuel burning appliance, such as an open fire or log burner.
The legislation however does not cover gas appliances such as a gas boiler or gas hob.
If enough carbon monoxide is inhaled, it can cause permanent heart, lung or brain damage, or even prove fatal.
Symptoms of carbon monoxide poisoning are similar to a cold or flu and can include headaches, sleepiness, nausea and vomiting, short-term memory loss, fatigue or exhaustion and shortness of breath.
Around 50 people die each year from carbon monoxide poisoning, all of which can be prevented by fitting an alarm.
Detectors should be placed in or near every room with a heating or cooking appliance.
For further information and advice on being carbon monoxide safe, visit the Project Shout website.