TRU COMPONENTS CO2 Indicator (LED, Display, Alarm) Air quality monitor Assembly kit 5 V DC -40 - 80 °C

Aerosols, which are quickly distributed in closed or poorly ventilated interiors, can increase the contagion with Corona. According to the Commission, the risk of infection with SARS-CoV-2 can be significantly reduced by ventilation in the German Federal Environment Agency's interior air hygiene (IRK).
In ventilation by opening the windows, a shock ventilation with transverse ventilation would be optimal. However, this could also avoid excessive ventilation and cooling of the classrooms. To test this, at least one CO2 sensor should be installed in a room up to 50 m² to measure the CO2 equivalent value:
- at a CO2 concentration of less than 1000 ppm No action is necessary
- at a CO2 concentration between 1000 and 2000 ppm should be ventilated
- at a concentration of 2000 ppm or more, it is essential to increase ventilation, even to reduce the number of people in the room if necessary

Build your own CO2 traffic light
This kit is used to build and program a “CO2 traffic light” which can be assembled in the classroom, but also from home. The CO2 traffic light kit provides the following advantages:
- promotes and demands craftsmanship
- it is only ventilated when it is necessary
- the program for the NodeMCU is included, but can also be programd by itself (Computer Science, MINT)
- when the kit has been completed, it can be used in the classroom/house remaining
- and the kit is sustainable: It can be dismantled at any time and rebuilt with other students

Programming
The kit consists of five components: The display, an RGB LED, a buzzer, a CO2 sensor and the NodeMCU:
NodeMCU: The NodeMCU V2 is a ESP8266 based development kit with open source firmware. With only a few Lua script lines, the module can design your own IoT project.
Sensor & Display: Here, the measured values are to be read from the CO2 sensor and output on the display
RGB LED: The RGB LED should display an index for the concentration via different colors. The colors red, green and blue are available for this purpose.
Buzzer: In addition, the buzzer can be activated briefly when the limit value is exceeded.

Effort / difficulty level
Our recommendation on the age levels for the individual activities is as follows:
- Place components on a breadboard: From 6. Class (handicraft)
- Connect components with jumper bridges according to instructions: Starting from 6. Class (handicraft)
- Programming the NodeMCU: From 10. Class up (computer science)

This text is machine translated.