This video shows why you cant always trust all information on the internet, as well as shows the basics of torque wrenches and a few oddball calculations you might run across when building custom things.
Underground mine ventilation. Underground mine ventilation provides a flow of air to the underground workings of a mine of sufficient volume to dilute and remove dust and noxious gases (typically NOx, SO2, methane, CO2 and CO) and to regulate temperature.
Abstract. Ventilation is the process by which air moves into and out of the lungs and is made available for gas exchange across the alveolar-capillary membrane.