CO2 sensor wired to Arduino Nano that outputs CO2 concentration values in serial monitor and plotter of arduino. Also a buzzer sounds when high level concentrations are detected and an RGB light changes its colour when it is below some concentration.

• CO2 sensor (CCS811)
• Buzzer sounds when CO2 concentration is bigger than 800
• RGB LED is red when CO2 > 1000 ppm
• RGB LED is blue color when (800 < CO2 < 1000) ppm
• RGB LED is off when concentration is below 800
• Optionally uncoment code lines to obtain blue (600 < CO2 < 800) ppm and green (CO2 < 600 ppm)

2. Arduino Nano

3. Breadboard

4. Buzzer

5. RGB LED

6. Computer with Arduino IDE installed
7. Cables
8. Resistances (0.2k, Optional)

Adafruit_CCS811

Thanks to mighelangelcasanova for sharing initial code:

https://github.com/miguelangelcasanova/codos/blob/master/dev/arduino/plotter/plotter.ino