woman in her living room enjoying fresh air

Breathe deeply - reduce the risk of infection: with spexor

How to measure indoor air quality with spexor

Regular ventilation reduces the spread of viruses


Good indoor air quality is currently more important than ever. This is because poor indoor air not only promotes headaches and makes people tired, but can also contain fine droplets and aerosols of varying sizes that are potential virus carriers. In times of Covid-19, alongside practicing regular hand-washing, social distancing and wearing a mask, ventilation is an important everyday measure to reduce the risk of infection and contain the spread of viruses indoors. Especially now in the cold season, when we are usually in closed rooms and spend a lot of time working from home.

Corona is transmitted by droplets containing the virus droplets (aerosols) that are so fine that they cannot be seen with the naked eye. There is a high risk of infection, especially with the smallest aerosols, as they remain in the air for several hours, pass through masks and allow viruses to penetrate deep into our lungs. Therefore, in addition to social distancing, hand-washing and masks, regular ventilation is strongly recommended to reduce the risk of infection with Covid-19.

spexor supports you in this and helps you to keep an eye on the air quality in closed rooms and informs you when it is time to ventilate. With fresh air you not only reduce the concentration of CO2, but also viruses or other harmful substances. This way you stay healthy and efficient.

spexor is not only a smart alarm device that warns you in case of an intrusion, but can also measure and assess the air quality in your home by continuously measuring the amount of VOCs in the air. This makes spexor more accurate than a CO2 measuring device.

spexor at home

spexor measures not only CO2, but VOC in your indoor air - this makes it even more accurate

spexor can do more than a CO2 meter by measuring the proportion of VOCs in the air. These are so-called volatile organic compounds (VOCs), i.e. substances that are gaseous and vaporous and thus present in our air. Our indoor air is composed not only of the air we breathe, but also of vaporized sweat and other biological processes. Substances that we don't think of directly such as solvents, liquid fuels, or synthetically manufactured substances are also present in the air. Such substances are everywhere in your home - in floors, wall and ceiling materials, paints, varnishes, adhesives, furniture, care and cleaning products.

Spexor's sensors measure hundreds of components commonly referred to as contaminants. This type of air quality determination is therefore much more comprehensive than just measuring CO2 and thus offers an enormous advantage.

woman using the bosch spexor app

Always keep an eye on air quality with spexor

With just one look at the spexor app, you can see what the air quality in the room is at any given moment. Thanks to the intuitive color display, it is immediately clear whether the air is good, moderate or even bad. Spexor measures air quality every 30 seconds and transmits the data to the app every 5 minutes when power save mode is disabled or every 15 minutes when power save mode is enabled. It is also possible for spexor to inform you via the LED display, when ventilation is required. spexors LED display is slightly faster than the display in the app.

This makes spexor ideal as a measuring device for air quality. In addition, the app supports you with recommendations for healthy indoor air.

woman opening her windows for fresh air

How to ventilate properly?

Proper ventilation is important because there are many possibilities and therefore many sources of error. The goal is to replace the bad air as completely as possible with fresh air from outside. The most sensible way to achieve this is to create a draft in which two opposite windows are completely opened. If this is not possible, it is recommended to open as many windows as wide open as possible.

Especially in winter, in order not to freeze, the windows are often tilted for a longer period of time. However, the exchange of air is very poor. Often only the warm heating air is exchanged, while the aerosol containing air remains in the room. Although the air in the room gets colder, proper ventilation works differently. Therefore, especially throughout Covid-19, it is important to properly ventilate for 3-5 minutes rather than leaving the windows on tilt.

Do you still have questions?

Click here for our FAQs.

Please note that the air quality measurement is already available for some users as part of our christmas promotion. All others will soon be able to activate this function via in-app purchase. We will inform you via our newsletter and facebook as soon as this is possible.

How it works

spexor app

Configure the air quality display

In the settings of your spexor app to the right of the "Air Quality" tile, you can use the gear wheel to adjust the display to your needs. You can define the intervals at which spexor should show you whether the air in your room is good or bad, whether you would like to deactivate the air quality LED display completely or whether you would like to have a permanent air quality LED display. You can also choose the level at which you want spexor to inform you.

Please note: The light signal is only displayed if surveillance is not active. Also the LED display is slightly faster than the display of the values in the app, as the communication via the servers takes some time.

spexor app

Air quality display in the app

In your spexor app, you can easily keep an eye on the air quality. On the start screen, the air quality is displayed in color and with an explanation:

green = very good, good
orange = moderate
red = poor, very poor

The app also supports you with recommendations for healthy indoor air.
Please note: It can take up to 12 hours until the first value is displayed in the app (self-calibration of the sensor), after that the sensor will get used to the respective environment within a few days. Therefore, we ask for a little patience for the first exact measurement values. It is also important that the latest device software and app version are installed.

LED signal of spexor lights up in different colors

Air quality display by light signal

It is also possible to configure the settings so that spexors LED display gives you a light signal when it is time for ventilation. If the LEDs are red you know that you should open the window. If the LEDs light green again, the window can be closed. Orange means that the air is not really good but not really bad either - ventilation can help if the quality of the outside air is better. This way you can easily measure and display the air quality in your home without having to constantly look at your smartphone.

Please note: Turning on the LEDs for displaying the air quality in the room has a noticeable effect on the battery life.

Expert interview with Dr. Richard Fix

Dr. Richard Fix, product manager for environmental sensors at Bosch Sensortec answered the most important questions about indoor air quality and VOC measurement and explained, how the sensor built into spexor helps people live smart and healthy lives #LikeABosch:

spexor: Aerosols play a major role in the transmission of Covid-19 . What exactly is this and how are they distributed in enclosed spaces?

Richard Fix: Aerosols are a mixture of solid and liquid suspended particles in a gas. Our exhaled air is such a mixture. If someone is infected, the aerosols also contain viruses and can thus reach other people. Larger droplets and particles in the exhaled air sink to the ground relatively quickly. The smallest suspended particles, however, are only a few nanometers in size and can remain in the air for hours, under the right conditions, so they can be distributed everywhere with normal air currents

spexor: Does this mean that the risk of infection increases if we spend more time indoors in winter?

Richard Fix: Exactly, and in my opinion, the current infection rate reflects this: in the colder season, we are indoors more often and, usually, the windows are closed. As a result, there is an increase in exhaled aerosols in the indoor air and, in the case of at least one infected person, also viruses. Due to the higher concentration, there is also an increased risk of infection.

spexor: Does ventilation help and if so, how do you ventilate properly?

Richard Fix: Ventilation is - together with keeping distance, hygiene and breathing mask - an important measure to reduce the risk. Through ventilation, you remove the aerosols & viruses from the room air. Correct ventilation means exchanging the room air as completely as possible. If it is much colder outside, you want to achieve this as quickly as possible in order not to lose unnecessary heat. To do so, open several windows or doors completely (if possible opposite each other, so that there is a draft). This way, a few minutes are enough to completely exchange the air and the walls do not cool down. This should be repeated as soon as the amount of exhaled air in the room has increased.

spexor: How do you find out when you need to ventilate and how can the air-quality sensor in spexor help?

Richard Fix: How often you need to ventilate depends on how large the room is, how many people are in the room and how many windows and doors you can open. There are, for example, apps, where you enter this information and it calculates how often and how long you need to air the room. An air quality sensor simplifies this enormously. It informs you as soon as the amount of polluted air is too much and you should start ventilating. It also gives feedback as soon as there is enough fresh air in the room and it is better to close the windows again. Too much ventilation does not make sense in winter. Of course, because you freeze. But above all, it is counterproductive. When the room has cooled down and the air in the room is no longer much warmer than the outside air, the air exchange also takes place slowly - you cannot get the bad air out as easily. In addition, cold and dry air ensures that aerosols can remain in the air for a very long time. It is no coincidence that the biggest known superspreader events in Germany this summer were in refrigerated warehouses!

spexor: In simple terms, what are VOCs?

Richard Fix: "Volatile Organic Compounds" is the generic term for thousands of volatile organic compounds that can occur in the air. Our exhaled air contains numerous VOCs, and our air quality sensors are developed and qualified to detect a so-called "breath-VOC" mixture. VOCs also include vapors and odors, both from us humans and from objects and processes. The German Federal Environment Agency recommends that the sum of all organic compounds in indoor air should remain below a certain concentration.

spexor: What is the difference between measuring VOCs with spexor and measuring with CO2 traffic-lights?

Richard Fix: VOC sensors can detect almost all organic contaminants in indoor air. That is why they are called air quality sensors. We want to breathe in fresh, clean air, so essentially nitrogen, oxygen and a reasonable amount of moisture. Anything else in the air is usually a contaminant. CO2 sensors only detect CO2 and nothing else. The measurement of CO2 in room air goes back to Prof. Max Pettenkofer, who in 1858 coined the guideline value of 1000 ppm CO2. From a chemical point of view, however, CO2 itself is a fairly non-reactive gas, which itself has hardly any effect on our well-being. On the International Space Station (where you can't open windows ;-)) the CO2 value is regulated to 5000 ppm. Extensive studies by NASA show that this is sufficient and that it is especially important to filter out all other impurities from the room air. Human exhaled air is reliably detected by VOC and CO2 sensors. A VOC sensor may require ventilation a little earlier or more often since it also detects numerous other impurities. We consider this to be sensible.

spexor: How does regular ventilation affect the risk of infection?

Richard Fix: Clearly, the risk of infection is reduced because regular ventilation ensures that no increased virus concentration occurs in the air. More recent studies also assume that an increased virus concentration during infection can also lead to a more severe course of the disease.In other words, if you ventilate properly, you not only reduce the risk of infection but possibly also the consequences of infection if someone becomes infected nevertheless. The figures of the current infection incidence in comparison to spring speak for this.