We have compiled frequently asked questions for you here.


How does the LuftLicht work?

The LuftLicht measures the CO2 content in the room via an NDIR sensor (non-dispersive infrared sensor). The sensor is mounted in the LuftLicht and receives room air via ventilation slots on the floor. Thus, the sensor is not mounted in a direct draft of air and therefore measures fluctuation-free and reliable. Depending on the CO2 concentration, radially mounted LEDs color the LuftLicht green (up to 1000 ppm), yellow (between 1000 ppm and 2000 ppm) or red(from 2000 ppm) and thus provide clear information on the air quality.

Is the LuftLicht eligible for funding according to the Bavarian Federal Directive?
The LuftLicht meets all the eligibility requirements of the Bavarian state government. The following features are important:
1. the LuftLicht measures real CO2 and not only CO2 equivalents. Attention: Since the sensors for real CO2 are much more expensive than for CO2 equivalent (often referred to as V-CO2), most inexpensive devices only measure V-CO2.
2. the measuring range of the device goes up to 10000 ppm, the state government prescribes a measuring range up to at least 3000 ppm.
3. the device alarms via three-colored warning lights (green up to 999 ppm, yellow warning level from 1000 ppm, red warning level from 2000 ppm as specified by the state government).
This makes the cost of the LuftLicht 100% eligible.

What is the difference betweenCO2 and CO2 equivalent?

In order to measure the real CO2 content in the air, special sensors and measuring methods are required - in our case, the reliable NDIR measuring method, in which CO2 is measured via infrared. Since these sensors are expensive, some suppliers use much cheaper sensors to measure CO2 equivalent (so called V-CO2). Under certain conditions the measured values of real CO2 and V-CO2 correlate. However, a V-CO2 measurement can quickly be falsified. More about this in the next section.

Why is measuringCO2 equivalent (so-called V-CO2) problematic?

CO2 amps that measure V-CO2 (these are especially devices under 100 €) are problematic for two reasons.
1. V-CO2 sensors also strike at other gases. In particular, V-CO2 meters are triggered by vapors from carpets, jackets, but also deodorants and shaving lotions. As a result, V-CO2 sensors indicate an increased concentration much more frequently, although this is falsified by other influences. Especially in classrooms with many students, it is therefore not possible to conclude from a V-CO2 value to the real indoor CO2 concentration.
2 In the funding guidelines of the Free State of Bavaria, "the measurement of CO2" is stated as a prerequisite for eligibility for funding. As soon as not real CO2 but a CO2-equivalent is measured, the eligibility for funding can expire.

How do I have to operate the LuftLicht?

Simplicity and user-friendliness were important goals in the development of the LuftLicht. We therefore decided to use a self-calibrating sensor. So you don't have to carry the LuftLicht out into the fresh air or make manual setups, as with most inexpensive devices. The only thing you need to do is to give the sensor fresh air at least once a week. The sensor remembers the lowest value (value with fresh air) and measures the deviation from this. The sensor remembers the lowest value for up to 7 days. As long as you ventilate at least once every seven days, you can simply plug in the LuftLicht and it measures completely by itself.

Can the LuftLicht also be operated by battery?

We developed the LuftLicht in close cooperation with schools. A major disadvantage of battery-powered CO2 traffic lights is maintenance. Someone has to take care of checking the batteries regularly and changing them if necessary. In addition, teachers wanted the CO2 traffic lights to be stationary, i.e. either fixed to the wall or lockable to prevent theft. For these reasons, we have equipped our LuftLicht with a power supply unit. Since the nearest power outlet may not be a few meters away, the LuftLicht comes with an extra long cable.

Does the LuftLicht have a wall mount?

The LuftLicht has a keyhole suspension on the back, so it can be mounted on the wall with a single screw. Note here the recommendation to mount the LuftLicht at a room height of about 1.5 meters and not directly next to a window.

Does the LuftLicht have anti-theft protection?

Yes. From our discussions with teachers and other target groups such as doctors or restaurateurs, the concern about possible theft came up again and again. We have therefore installed a device for a so-called Kensington lock (also known as a laptop lock). This allows the LuftLicht to be attached in a theft-proof manner.

Can I change the limits?

Clear YES. In order to comply with the applicable funding guidelines, the limit values cannot be changed and are set by us. If the subsidy is not relevant for you or if you want different limit values for another reason, we can set the limit values individually for you from a certain order quantity.

Is there a signal tone?

No. For the current version of the LuftLicht, we decided against a beep tone. The reason for this was that students in particular should not jump up in panic as soon as the limit value is reached. Much greater was the desire for a discreet but still permanently visible signal that encourages orderly ventilation.