Clean rooms are rooms in which the air contains a certain amount of dust particles, chemical vapors, microbes. Clean room ventilation controls temperature, humidity and pressure. Cleanrooms are being built in medical and research centers, electronics and drug factories.
During the construction of the premises, the minimum penetration of dust into it and the impossibility of its accumulation is provided.
Ventilation of clean rooms
Cleanliness is ensured by a clean ventilation mode. The scheme for creating air purity is to create excess pressure in comparison with the adjacent halls. And this is achieved by increasing the air flow above the outflow by 20 percent or more in rooms without windows and by 30 percent or more if the room faces the street. Thus, the clean ventilation mode allows the removal of air from the clean room to the adjacent ones. Air purity is also ensured by filtration. Special filters capture 99.99% of particles with a diameter of 0.12 microns.
Air movement in clean rooms
The ventilation mode for clean air has a number of features specified in the relevant GOSTs. Air jets in rooms should be directed downward laminar, without turbulence. This direction of air blows particles of dust and dirt from mechanisms and people downward.
In addition, the air is supplied in such a way that no stagnant corners remain in the hall. The temperature and humidity of the air supplied by the units are also regulated.
There are three levels of indoor air cleanliness: moderate, medium and hard.
The ventilation mode of clean air is provided by the following equipment:
- Exhaust fans, supply fans, recirculation fans;
- Air intake mechanisms;
- Finishing filters;
- Air distributors;
- Air movement control mechanisms;
- Sensors;
- Regulating equipment;
- Gateways;
- Remote Control;
- Fan modules with filters;
- Pass-through windows.
Air parameters in clean rooms
According to international standards, the clean ventilation mode must provide an air speed of 0.35 to 0.51 meters per second with an error of 20 percent. The lower limit is allowed for rooms with a small number of employees doing clean sedentary work.
It is recommended to set air exchange from 30 to 60 times per hour.
