Carbon monoxide (CO) is difficult to detect because it is colourless and has no taste or smell.

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These include the exhaust gases such as nitrogen oxides (NOx), non-methane volatile organic compounds (NMVOCs), and carbon monoxide (CO).

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Cornwall Fire and Rescue Service has seen more than a five-fold increase in carbon monoxide (CO) poisoning cases over the last 12 months, it said.

BBC: Fire service sees rise in carbon monoxide poisoning cases

The highly reactive oxygen combines with hydrogen and carbon monoxide on the fuel side to make water and CO 2.

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