A bag house also known as a bag house filter, bag filter, or fabric filter is an air pollution control device and dust collector that removes particulates or gas released from commercial processes out of the air. Dust-laden gas or air enters the bag house through hoppers and is directed into the bag house compartment. The gas is drawn through the bags and a layer of dust accumulates on the filter media surface until air can no longer move through it. When a sufficient pressure drop occurs, the cleaning process begins. Cleaning can take place while the bag house is online (filtering) or is offline (in isolation). When the compartment is clean, normal filtering resumes.