How to improve air quality in kindergartens and schools?

Good afternoon, Enkhtuvshin. Initially, you need to understand how crowded.

Calculations are made in accordance with the instructions SanPiN and SNiP 31-06-2009. It is calculated according to a simple formula - according to the requirements, the air exchange for one student should not be lower than 16 m3 / hour. Those. 30 students x 16 m3 / hour = 480 m3 / hour plus one teacher must be added.

Depending on the load per adult:
- at a minimum of 25 m3 / hour;
- average 45 m3 / hour.

We will proceed from a minimum of 480 m3 / hour + 25 m3 / hour = 505 m3 / hour.

Now we need to calculate the cubature of the class. In old Soviet-built schools, the class area is very different, it can be from 38 m2 to 65 m2. We will proceed from the fact that the area of ​​one class is 50 m2, and the ceiling height is 3.3 meters. The volume is 50 * 3.3 = 165 m3.

We calculate the necessary rate of air exchange per hour 505 m3 / hour: 165 m3 = 3. That is, three times air displacement should occur within one hour.

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What can be done:

1. Install a supply valve for windows on all windows. For clarity, see fig. 1. Under ideal conditions, one window supply valve replaces 40 m3 / h. Suppose in one class there are three windows and all three windows with wings. 3 wings * 40 m3 / hour = 120 m3 / hour. And we need 505 m3 / hour. This option is not suitable for conditional source data.

2. Install the cassette ventilation unit ceiling or wall. In the direct sense, the cassette ventilation device is a filter that is installed on an existing supply or exhaust ventilation duct. Figure 2, is clearly depicted for understanding. It seems to me that I mean the supply and exhaust system, sometimes called a recuperator. In this case, just choose the model of the required power. There are a number of modifications: from simpler to multifunctional. One of the simplest in fig. 3.

Even in the most budget models, the air enters the room warmed up.When buying, pay attention to the range of operating temperatures, focusing on the climate in your area. It is important to pay attention to the minimum operating temperature. Installation takes no more than an hour and causes minimal damage to the repair. Prices start at 12,000 rubles.

As a result. For economic feasibility, it is necessary to calculate for each room, acting on the above example. Based on the data obtained, it is quite possible to install a supply valve, which will be the cheapest option. If you need to install a recuperator, you will clearly understand the required power and correctly adjust the necessary budget.

Additionally, I advise you to read the articles on our website about forced-air and exhaust installations and recirculation ventilation.

Good luck.