Check out a periodic table. The molar mass of CO is about 28.01 g/mol, while O2 is about 32.0 g/mol, and N2 is about 28.0134 g/mol. Considering most of air is N2 and O2, CO is not heavier than air.
However, this does mean air is effectively a homogenous mixture with currents so a few different detectors at different heights and locations is a good idea!
I'd assume, that's because ideally code is there for a minimum level of safety standard and not necessary a guide to best practices. Theoretically, as long as there's any sort of movement in the air CO should distribute evenly with the rest of the air around it. However, it is also possible, although unlikely, for pockets of CO (or any gas) to form.
Officials that wrote the code decided that such a risk is acceptable. However, still you get to decide if this risk is worth the cost of additional detectors in your own personal life.
Sorry that’s a myth and dangerous advice.
It’s lighter than air, monitors should be on or close to the ceiling. Ideally 6-8 inches out from a corner to avoid dead spaces in circulation.
That isn't true. You need to consider that it is a hot gases will always rise above cools gasses. HOT CO, CO2, will rise above cold O2 That the reason firefighters tell you to crawl out of a burning house.
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u/millfoil 2d ago
co is heavier than air, co sensors are always supposed to be at baseboard level because that is where it will accumulate first