With coronavirus infections once again on the rise, primary and secondary education minister Dennis Wiersma is making CO2 monitors in classrooms mandatory.

Despite thousands of the air quality-monitoring devices having already been installed in classrooms nationwide, some 40 percent of schools still don’t have them in all classrooms, reports NOS. ‘A number of schools have not gone that far yet, so we need to step up a bit,’ says Wiersma.

Research shows that tracking carbon dioxide levels indoors is a cost-effective way to monitor the risk of coronavirus infection. When excess CO2 levels double, scientists found, the risk of transmission also roughly doubles.

The CO2 monitor obligation will take effect from the next school year. New builds and renovated primary schools are already required to install them, but now existing schools must as well. Wiersma, who has allocated €17 million euros to help with the costs, is urging schools to do it sooner rather than later.

There are approximately 9,000 school buildings in the Netherlands—many of them old and outdated—with 2.5 million students and 285,000 people employees. Schools played a huge role in contamination spread during previous coronavirus waves, and the government wants to avoid closing them again.

The minister also wants to promote the use of air purifiers in schools, with subsidies available for those that work on improving ventilation. ‘Teachers and students have the right to healthy air in the classroom,’ he said. ‘Especially in this corona time, we must do everything we can to keep schools open in a responsible manner.