Training my sense of CO2 ppm

Re:Training my sense of CO2 ppm by rootusrootus on Saturday July 16, 2022 @06:14PM (#32122431)

The Aranet 4 claims it can measure up to 5000 ppm with +-3% accuracy. But you'd have to take their word for it, I guess. For $250 I'm hoping it's not a crap sensor.

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Re:Training my sense of CO2 ppm by MatteoFrigo on Saturday July 16, 2022 @06:49PM (#32122671)

The usual convention is that the accuracy refers to full-scale measurements. I.e., your device has an error of +-3%*5000ppm = +-150ppm. At ~400ppm you are about 37% off.

Human exhaust breath contains about 5000ppm CO2, so this device is decent for measuring humans. It's less decent to measure atmospheric CO2.

Edit: looking at the datasheet, the device claims +-30ppm and 3% of reading, which I interpret as "whichever is greater". Thus, the device would be +-30ppm up to 1000ppm, and 3% of the reading above 1000ppm.

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Re:Training my sense of CO2 ppm by tgsovlerkhgsel on Saturday July 16, 2022 @07:27PM (#32122891)

I interpret the error as a sum, i.e. at 500 ppm, an error of up to 45 ppm (30+0.03*500).

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