dating advice: 7 Blunders One Females Help make
In the prevention, hygiene and health promotion measures against covid-19 for educational centers in the 2020-2021 academic year, the Ministries of Health and Education indicate the need to ventilate at least 10-15 minutes at the beginning and at the end of the day, during recess, and whenever possible between classes (some autonomous communities also advise during classes), keeping the windows open as long as possible and with the necessary accident prevention measures. The fresh air supply should be increased and the indoor air recirculation function should not be used.
With the help of sensors or meters for CO2, a gas that is a good indicator of human bioefluent emissions. They cost between 100 and 300 euros. The concentrations they indicate are used to calculate the air renewal in a given space and conditions (students per classroom, cubic meters of the class, etc).
The CSIC guide offers two methods to carry out these calculations, although you can also consult the one on the five steps from Harvard University or its calculator developed together with the University of Colorado.
As a reference, CO2 concentrations in outdoor air can be considered to be around 420 ppm (parts per million), and that inside buildings it is not recommended to exceed 800 ppm. In specific locations where the calculations are complex, the service of ventilation and air treatment professionals is also recommended.
While the pandemic lasts, there will be a choice between reducing health risks and thermal comfort. Do not rule out wearing warm clothing inside the rooms. Having it indoors will not overuse the heating with partially open windows.
In any case, if natural ventilation is not feasible due to adverse weather conditions or other factors, artificial or forced ventilation can be used, which is carried out by means of extractors, air impellers and other mechanical elements.
In the case of centralized ventilation systems, the outdoor air rate should be increased as much as possible and recirculation should be kept to a minimum. And if it is not possible to resort to any ventilation measure, which would be the most desirable, at least the air should be purified with equipment equipped with filters, such as HEPA.
They are air cleaners that filter their particles efficiently (High-Efficiency Particulate Air in English, hence their name). These portable devices equipped with a dense fiber mesh eliminate a large part of the aerosols from the current that passes through them, thus retaining the viruses that they could carry.
The purifier should be placed in the center of the room if possible, and should not blow directly towards the occupants. Their price ranges from less than 500 euros to several thousand, so experts advise to assess well if they are really needed and in what places in the center.