As we get closer to the start of classes, the debate about returning to in-person classes becomes more and more intense. There is no doubt that it is essential to return to the classroom, both for the learning process and for the socialization of children, which was strongly affected during 2020.

Fortunately, technology brings us solutions to face this challenge. One of them consists of monitoring the environment of classrooms and closed spaces.

How to quantify COVID-19 risk using IoT

Ventilation is the main recommendation in closed environments to reduce the risk of spreading COVID-19. This is because air renewal keeps the potential viral load in the environment at low levels and contagion is less likely.

CO concentrations2 above 1,000 ppm can cause discomfort, such as fatigue, loss of concentration, fatigue, or headaches. Concentrations above 750 ppm may cause odors. 

Therefore, what must be done is to monitor the ventilation of the environments. This can be achieved by measuring the concentration of carbon dioxide ( CO2 ).

Human beings use oxygen ( O2 ) to carry out our metabolic functions and we breathe out CO2. Therefore, measuring the concentration of CO2 gives us an indirect but effective indication of the level of ventilation in an environment.

Which sensor to use

To meet the objective of measuring CO2 there are many options in terms of sensors, devices and systems.

CO2 sensors, like all gas sensors, have their complications. Factors such as measurement range, accuracy, sensitivity to contamination and measurement drift over time are important when choosing the right sensor.

This is why there are very varied price ranges in CO2 sensors. Obviously it is not the same to measure CO2 in a medical research laboratory as it is in a school.

covid-19 escuela iot

Selection of the type of solution

There are many commercial off-the-shelf products with different features. Some of them are display, alarm, communication interface, type of sensor used.

The first factor to consider is the type of solution you want: isolated or IoT.

isolated solution

The isolated option consists of a device that measures the CO2 concentration and shows it on a display or emits an audible alarm to warn that the threshold has been exceeded. It could also activate the ventilation through a digital output (ON/OFF).

IoT Solution

The second option is an IoT-enabled sensor or device. That is, that it has a communication interface that allows it to be integrated into an IoT solution. There are many options and the choice of communication technology will fundamentally depend on the availability of infrastructure and the distances to be covered.

Another factor to consider for the IoT solution is the choice of the IoT platform to be used. Many manufacturers offer their own IoT platforms for their products, which greatly simplifies and speeds up system implementation. Undoubtedly this is an important factor in these times.

In addition, an IoT solution in the cloud allows for centralized management of sensors, regardless of geographic location, which facilitates the addition of new sensors, the detection of failures, the management of the data generated by the system and the management of alarms.

On the other hand, the use of an IoT system in the cloud also reduces the initial costs of implementation.

In addition to sending notifications and alarms, building ventilation controls can be integrated so that they are activated automatically.

Other integrations

In addition to using CO2 sensors, other types of sensors or systems can be integrated, such as those for measuring body temperature, social distance, people counting, etc. In this way you can have a more complete picture of the situation.


The COVID-19 pandemic has presented unexpected challenges in our daily lives. However, with intelligence and innovation we can find solutions to overcome them.

With the proposals described in this article, the risk of spreading COVID-19 can be significantly reduced.

IoT technologies have undoubtedly played a very important role in this regard and will continue to do so.

If you liked this article, I invite you to share it with your contacts and leave your questions or comments below.


Leave a Reply

Avatar placeholder

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: