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How do I check if the Carbon Monoxide sensor is working?

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How do I check if the Carbon Monoxide sensor is working?

Postby eDiver » Tue Nov 10, 2015 10:07 am

Q: I just got my cootwo and it seems to be working fine, but the CO indicator is always 0. How can I check if it is actually working?

A: The simplest way to check if the Carbon Monoxide sensor of your cootwo analyzer is working is to perform a bump test using your breath.
According to a paper from Ryter and Choi, the exhaled CO value of non-smokers could be about 3 ppm while the mean value of exhaled CO for smokers was 17 ppm.

Before you perform a breath check, you might want to enable the display of the decimal digit (to display "0.0" instead of just "0"). To do so, connect to your cootwo, go to the settings and enable "Display Decimal".

Now, take a long long breath .... hold it as long as you can .... and then slowly exhale it into your cootwo.
If you are a non smoker you might see values up to 3 ppm. If you are a smoker the CO value could be much higher.

The other thing you will notice is that the O2% value will change too (decrease).

More you hold your breath before exhaling and more the CO and O2% values will change (CO will increase and O2% will decrease).

See below the result of a bump test as displayed by the My Nitroxbuddy app (in Monitor mode)

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