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Choose High Performing Underground Vent Systems Underground mines of all sizes need a well-planned ventilation system to deliver fresh air to all working places. Mine ventilation is the process of supplying sufficient fresh air to the underground workings to achieve these purposes ensuring proper distribution use of the air and controlling the return to surface of contaminated air. Mine ventilation is vital to dilute and remove gases dust heat and to supply oxygen for breathing and for engines. Mechanical equipment is used particularly in large-scale mining for a variety of purposes and is a source of several potentially toxic gases as well as of heat. Only diesel engines should be used underground in a mobile not static application. Various gases may occur naturally in mines due to geological processes decay of timber and other organic material and other causes. Coal mines are specifically susceptible to the presence of natural gases. These include toxic gases such as hydrogen sulphide H2S but the most significant are flammable gases of which the most common is methane. However other flammable gases may occur. Also flammable gases may occur not only in coal mines but also in metallic mines.

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Although the process of ventilation in underground mines may seem relatively simple getting the right quantity and quality of air to where it is required when it is required in an expanding mining environment is an elaborate operation that needs an array of ventilation components. Typical ventilation systems consist of the main fan system air regulators and doors that distribute air through the mine. There are also auxiliary systems that ventilate local production areas and workshops. Air requirements in an area depend on its location the number of people there and which machines are being used. The contaminants to be controlled by dilution ventilation are primarily gases and dust although ionizing radiations related with naturally occurring radon may present issues particularly in uranium mines and where the background uranium concentrations of the host or adjacent rocks are elevated. The amount of air needed for dilution control will depend on both the strength of the contaminant source and the effectiveness of other control measures such as water for dust suppression or methane drainage systems in coal mines. The minimum dilution air flow rate is determined by the contaminant needing the greatest dilution quantity with due cognizance of the possible additive effects of mixtures and synergism where one contaminant can enhance the effect of another. Primary Underground Vent systems are associated with ensuring the flow of air through interconnected mine openings. The overall ventilation network has junctions where three or more

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airways meet branches that are airways between junctions and meshes which are closed paths traversed through the network. Although most underground vent networks are ramified with hundreds or even thousands of branches the number of main intake and return or exhaust airways is generally restricted to less than ten. So find proper Underground Vent to ensure proper flow of fresh air in underground mines.