News about WERMA

15 Sep 2021

"We can ensure a safe return to school!"

WERMA CO2 traffic lights promote correct ventilation in classrooms and daycare centres

The big reunion after the summer holidays: school begins again this Monday in Baden-Württemberg, Germany. Just in time for the start of school, the state of Baden-Württemberg is providing 70 million euros for the purchase of mobile CO2 sensors and air filters (for details, see the funding guidelines of the German Ministry of Education dated 06/08/2021). These devices can help to keep infection rates in schools and daycare centres to a minimum.

"We are extremely pleased that our solution can contribute to a safe and healthy school life", says Manuel Schutzbach of the Technical Sales department at WERMA Signaltechnik. The clever CO2traffic light, made by the company based in Rietheim-Weilheim, Germany, is a simple, straightforward and easy-to-understand solution that continuously measures the current carbon dioxide (CO2) concentration in the ambient air. Three traffic light colours accurately indicate whether or when it is time to air the room. This regular ventilation is intended to protect all persons who are required to remain in closed rooms for longer periods of time from a COVID-19 infection and other infectious diseases.

Clever, safe and easy to understand

Many schools and daycare centres have already been using these innovative traffic lights for quite some time to guarantee teachers and pupils alike the maximum level of safety. "The official advice is to air rooms every 20 minutes. But when we teach 20 or more pupils in a classroom, the CO2 traffic light shows us that we urgently need to air the room after 10 minutes at the most", says Manuel Vogel, mathematics, chemistry, science and technology teacher at Spaichingen secondary school. He is delighted by the new traffic light system and pleased that it is well accepted by the children in particular: "The traffic light is clear, easy to understand and needs no explanation. Our pupils usually notice that the traffic light signal has changed to amber before the teachers. They even squabble about who gets to open the windows".

Furthermore, the CO2 traffic lights are not a short-term investment, but provide permanent benefits for classrooms: "Low CO2 content in the room not only protects against infection, it also improves the concentration and performance of all those present", says WERMA's Manuel Schutzbach.

To ventilate or filter?  That is the question

It is up to the individual establishment to decide whether to purchase air filters or CO2 traffic lights. Filter systems are more expensive to purchase and maintain due to their power consumption levels. Furthermore, these devices use motor-driven fans, so the noise level generated can disturb a class, depending on the model employed. In contrast, CO2 traffic lights are equipped with long-lasting and energy-saving LEDs, are absolutely silent, ready for immediate use without any installation work and are significantly cheaper to purchase.

Versatile use of CO2 traffic lights

At WERMA Signaltechnik, the production of CO2 traffic lights has been running at top speed for several weeks. "We have produced several thousand CO2 traffic lights here in Germany so far", says Manuel Schutzbach. "Approximately half of the items delivered went to schools and daycare centres; the other half went to industrial companies and public institutions, such as offices, training facilities, production areas, vaccination centres, courtrooms and other administrative facilities."

The WERMA CO2 traffic light

WERMA's solution for CO2 measurement in indoor air consists of a three-tier signal tower, which is immediately ready to use and very easy to install thanks to Plug & Play: simply plug in the supplied power supply unit, wait until self-calibration has been completed and the traffic light is ready to use. The system instantly measures the current CO2 concentration in the ambient air and displays the result using three traffic light colours:

  • If the CO2 concentration is below 1000 ppm, the traffic light is green, indicating that the air quality is OK.
  • If the CO2 concentration exceeds 1000 ppm, the traffic light turns amber and indicates that ventilation is recommended.
  • The red signal indicates that ventilation is required as the CO2 concentration has risen above 2000 ppm.
  • If the limit of 3000 ppm is exceeded, a red flashing light indicates an acute need for ventilation.

The signals are clearly visible from all sides thanks to the 360-degree illumination and the extremely bright LEDs guarantee that they are clearly visible even in direct sunlight and bright surroundings.

Press contact

Udo Skarke
General Manager • WERMA USA

Tel. +1 (470) 361 / 0600
us-info@werma.com