What is the function of an individual vent in plumbing?

An individual vent serves the crucial purpose of venting a fixture trap. In plumbing systems, traps are used to prevent the escape of sewer gases into a building while allowing wastewater to flow through. However, as water drains through the trap, it displaces air, creating negative pressure that could lead to a siphon effect, potentially draining the trap and allowing gases to enter.

By providing ventilation specifically for the fixture trap, the individual vent maintains atmospheric pressure within the plumbing system, preventing siphoning and ensuring that the trap holds water. This is essential for maintaining sanitation and odor control within the plumbing system. The effective functioning of an individual vent helps ensure that fixtures operate correctly without risking the introduction of foul odors or gases into the living space.