EmpAIR Ventilation Advisor

This system was developed in collaboration within Empa from Lab 405 and Lab 503 . It could help to limit spreading of the corona virus.

CO2 sensor information/instructions
The system measures the CO2 concentration (additionally also humidity, temperature and air pressure) in your office or meeting room. It can be assumed that the CO2 level correlates with the virus aerosol concentration in case an infected person is present. The sensor helps to indicate when the room needs to be ventilated (based on FOPH CO2 recommendations Wegleitung zu den Verordnungen 3 und 4 zum Arbeitsgesetz, Artikel 16 Raumklima)  to bring back fresh and uncontaminated air.
app color code CO2 concentration (ppm) air quality (CO2 levels)
green < 1000 good
yellow 1000-1400 moderate   Download
red 1400-2000 poor   App
red blinking > 2000 unacceptable
The sensor is battery powered (3 x AA) and should last around 2 years. Place the sensor in your room; there is a magnet in the back and holes to mount it to a vertical surface if needed. The sensor is always on and broadcasts its sensor values. They can be registred by either an Android powered device or a custom made hardware. The instructions how to get the app can be found below. Each sensor has a unique identifier lasered on top of it that helps to identify your sensor in the app.

CO2 Sensor Android App
dowload description as printable-pdf
1. Download link for Android
Install the app from the Google Play Store:
or search for "EmpAIR", including the quotation marks!
2. How to install the app without Play Store
If you do not have Google services, download this installer to your mobile phone or tablet: Download (latest version v0.1.7; 01.12.20)
2.1. Download & open the file to install
2.2. Allow installations of apps from sources other than the Play Store 
2.3. Open the app
3. How to use the app

Open home page: Cube color depends on CO2 concentration 

Open graph page: Observe the CO2 concentration over time

Open sensor list page: Select a specific sensor 1)

Open info page for settings and information
Start logging to file 2)
Stop logging
Rescan available sensors and connect to the nearest one 3)

If the app cannot find sensors and your close to one: Enable location services in general on your device 
(Settings à Security and Location à Privacy à Location à On).

Clear the graph


1) Higher RSSI means a stronger Bluetooth signal 
2) Options and file path see info page
3) Open the sensor list page to see all available sensors