• A few days before the start of the school year, the need to equip schools with CO2 sensors to control indoor air quality and limit the spread of Covid-19 emerges.

  • The Minister of National Education, Jean-Michel Blanquer, said he was in favor of their deployment.

  • But the financing of this measure returns to the local communities, which do not have all the means to equip their schools.

Only three more sleeps before the children resume their school bags and go to school!

Back to school under close surveillance, against a background of the Delta variant and while children under 12 are still not eligible for anti-Covid vaccination.

The challenge for schools: to avoid clusters and class closures.

To guard against this, monitoring the quality of indoor air in schools is crucial.

The Minister of National Education, Jean-Michel Blanquer, thus recalled Thursday during his presentation of the back to school 2021-2022 his desire to "generalize CO2 sensors" within schools.

A wish left financially the responsibility of the local authorities, not necessarily ready to finance the equipment of all the schools which would request it.

Monitor indoor air quality in schools

"Children [under 12 years] not being vaccinated in the classes, we must find systems to prevent contamination and the circulation of the virus between children," insisted Tuesday Guislaine David, general secretary of Snuipp -FSU, the first primary school union. However, "we know that Covid-19 is transmitted mainly by aerosol in closed places, so measuring the concentration of CO2 [carbon dioxide that we exhale] is an effective way to see when the air must be renewed for reduce viral cloud, told

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Jérôme Marty, general practitioner and president of the French Union for a free medicine (UFML), which alert for over a year on the need to better control the air quality interior in enclosed spaces. "

“The CO2 detector indicates the moment when it becomes necessary to aerate: beyond 1,000 ppm [parts per million], or even beyond 500 ppm if we want to recreate the conditions from the outside, and thus allow the fall of contaminations in closed places.

The High Council of Public Health recommends not to exceed the threshold of 800 ppm in an enclosed place where the wearing of a mask is required.

Faced with a Delta variant which affects young children more than the previous strains, the President of the Scientific Council, Jean-François Delfraissy, also recommended better “school ventilation” and “the installation of CO2 sensors”.

"There is a scientific consensus to equip the classes," admitted Jean-Michel Blanquer in an interview with the 



Sensors that could be associated with air purifiers.

“One could imagine a CO2 detector connected to a screen that displays the air quality in real time and for all to see,” advises Jérôme Marty.

This would make it possible to be more responsive to ensure good ventilation of enclosed spaces, especially in canteens, where children remove the mask, eat and speak loudly, which increases the risk of aerosol projections.

In addition, ventilation is essential, but in winter, we cannot constantly open the classroom windows.

The second step would therefore be to enslave the CO2 detectors to air purifiers ”.

A cost to be borne by communities

But with CO2 sensors at a unit price of between 100 and 600 euros, who will foot the bill? Not the government: Jean-Michel Blanquer recalled that this type of expenditure was the responsibility of local authorities, which manage the equipment of schools. Regions, departments and municipalities will therefore respectively pilot the gradual deployment of CO2 sensors in high schools, colleges and nursery and elementary schools, in classrooms as well as in canteens.

And some communities have already taken out the wallet. “The department will make CO2 sensors available to establishments that request them. From the start of the school year, around twenty volunteer colleges will thus receive one or more sensors, before the device can be extended, ”informs the department of Seine-Saint-Denis. In Hauts-de-France, the region will provide "each high school with a portable sensor at the start of the school year" to be transported from room to room, explained to

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Manoelle Martin, vice-president in charge of high schools. Cost of the measure: around 120,000 euros for 300 sensors. An expensive operation, which does not include the purchase of air purifiers, at a much higher cost.

Carole Delga, president of the Occitanie region and of the Regions of France, confirmed the implementation of “mobile CO2 sensors” in high schools, “especially in places of school catering”.

But for communities, CO2 sensors represent a purchase that is difficult to finance.

For schools, they "are the responsibility of town halls", recalled the national secretary of Europe ecology-The Greens Julien Bayou.

"Which means that depending on whether the town halls are more or less endowed, there is an inequality with regard to health".

"The supply of this equipment was not anticipated"

The same goes for Guislaine David, who regrets that “Jean-Michel Blanquer does not develop financing for the purchase of CO2 sensors”. So, faced with the cost of these operations, the regional presidents wish to appeal to the State. Carole Delga has indicated that requests for financial support will be submitted to Matignon on September 13. “We implement the measures without having the budgetary answers, because it is a question of the health security of our children, of our youth. But here too, we are waiting for real answers, ”she said.

“A few days before the start of the school year, Jean-Michel Blanquer says he will help local communities to obtain CO2 detectors, but it is already too late! The supply of this equipment was not anticipated, criticizes Jérôme Marty. The problem of air cleaning, we seized the government in July 2020. To be effective in preventing contamination in schools, it would have been necessary to start supplying sensors several months ago. France is not the only country to want to equip its schools, Germany has already taken care of it, for example. And there, the minister thinks that, by a miracle, all the classrooms and canteens in France will be equipped in less than a week? It is an aberration! "

And the doctor continued: "This virus is not going to leave us, there will be other variants and if we want children to go to school in complete health security, we have to move and adapt.

"In the meantime, the Covid-19 screening tests in primary schools should be more generalized and more regular than what is planned by the National Education, failing which the start of the school year could be" very complex ", with closures of repeated classes, says the Scientific Council.

Jean-Michel Blanquer announced "a target of 600,000 weekly saliva tests" in primary schools, which welcome around 4 million students.


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