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roscoe81 / enviro-monitor

An environment monitor based on a Raspberry Pi Zero W, a Pimoroni Enviro+ and a Plantower air quality sensor to monitor, display and report on air particles, gases, temperature, humidity, noise and air pressure.
MIT License
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[Question] PPM readings vs other recommendation guides #15

Closed DR-DinoMight closed 2 years ago

DR-DinoMight commented 2 years ago

Hi

First of all, thank you for this.

Secondly, this is my first project like this of sorts, so you're repo, has really helped me understand how to use the Envrio+, outside of the examples, but I'm just wondering if you could explain a little bit more about the numbers, please?

I'm trying to make an indoor air quality sensor that I can use to keep tabs on my office, nothing super accurate, just something to let me know when changes are needed with the air quality, temp and humidity, so I'm trying to extend your code so that I can output overall quality regarding the factors mentioned, but when I come to work out the levels for the cO2 I see my reading are as followed in the json file

{"Time": "Sunday 06 February 2022 @ 10:29:01", "Run Time": 39005.0, "Raw Temperature": 35.84, "Output Temp": 24.21, "Raw Humidity": 17.07, "Output Humidity": 28.9, "Output Bar": 993.4, "Raw Bar": 972.4, "Oxi": 0.16, "Red": 3.31, "NH3": 0.89, "Raw OxiRS": 17448.0, "Raw RedRS": 310803.0, "Raw NH3RS": 66298.0}

and I know that the Red output is the one I'm looking for cO2 but when I compare that with some guidance of recommended cO2 PPM they don't correlate?

image Taken from here

Is there a table you used to work out good/bad ranges? Are your numbers shortened? or am I just completely getting the wrong end of the stick? (more likely 😅 ).

Many thanks for the help in advance!

DR-DinoMight commented 2 years ago

I have just realised that I could be completely getting the wrong end of the stick regarding RED and cO2 (ie not the same) so sorry if any of this just isn't making sense!

Ultimlatily just trying to find good ranges for Air quality 😅

roscoe81 commented 2 years ago

You're correct @DR-DinoMight, RED and CO2 are different. You could try the option of adding the SGP30 sensor that my code supports. It measures VOC and eCO2 (equivalent CO2) and I've found it useful for measuring indoor air quality.