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The purpose of aspiration is to localize the allocation of harmfulness, i.e. Do not allow the receipt of harmful substances from the source of formation of hazards during the technological process into the air of working premises.

The functioning of the aspiration system is due to the influence of the transport gas, usually air, on the particles of the substance being removed. Aspiration system creates a vacuum in local air intake devices and shelters of process equipment. It does not allow the entry of unwanted particles into the air of the room, removes waste products in the form of dust, shavings or sawdust. Usually the aspiration system transports the particles to be removed to a special equipment that catches them. The main tasks of the aspiration system are efficient and reliable air purification in the working area, protection of the atmosphere from pollution by emissions of harmful substances. Aspiration systems can be of two types. Depending on the location of the trapping devices in relation to the motive of the air movement (the fan), they are suction or pressure. Aspiration occurs in crushing, grinding, foundry, chemical and metallurgical shops. A distinctive feature of the aspiration system is the strongly inclined air ducts. In less dusty industries dust extraction ventilation is used (differs from the absence of inclined air ducts).
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