What is the primary purpose of an individual vent in plumbing?

An individual vent primarily serves to vent air from a fixture drain. This is crucial for maintaining proper drainage and preventing potential problems such as slow drainage or backflow. When water flows down the drain, it creates a vacuum that can impede the movement of waste; the vent allows air to enter the drainage system, which equalizes pressure and ensures smooth, uninterrupted flow. Proper venting is essential to avoid siphoning water out of traps and preventing sewer gases from entering buildings, which could be harmful to occupants. This makes the function of the individual vent essential for the overall health and efficiency of the plumbing system.