First, it is necessary to check the performance. Take a small sheet of paper (be sure to thin) to the ventilation hole, and release, if everything works well, the leaf will be pulled.
For a thorough check, a special device is used – a winged anemometer that measures the speed of air movement in the ventilation channel. But this is just the beginning. Ventilation performance is measured in m3/h, and in order to get the right information, you need to have a calculated table, and know the section of the ventilation grill. This also needs to be fulfilled by a number of conditions, the neglect of which will significantly change the accuracy of information.
The difference in temperature. The difference in air temperatures outside the building and inside the room should be at least 13 ° C. The difference is set in order to determine with higher accuracy, because in the warm season the ventilation works with less performance, and in severe heat, reverse traction is possible at all. Let me explain if the temperature is higher on the street than in the room, the air outside will fall under the strength of its weight, and the one that simply cannot push it out inside the building, and will fall down (physics).
Another point of the methodology is necessarily a ajar window of 5-8 cm. Since residential buildings are built with calculation for supply and exhaust ventilation, and natural air exchange was taken into account. And so that the air goes into the ventilation duct, he needs to get into the room from the beginning. Simply put, you need to create a draft in the apartment.
All these parameters and test conditions are indicated in a document called “Methods of field testing of air exchange of residential buildings”.
If all conditions are met, then the data obtained will be closest to the true. The norm for residential buildings is 60m3/h for the kitchen, 25m3/h for the bathroom and 25m3/h for the bathroom.
