What is the purpose of an individual vent in plumbing?

An individual vent serves the purpose of venting a single fixture trap specifically. This means that it allows for the escape of air and any gases produced by the drainage from that particular fixture. By maintaining proper air pressure in the drainage system, the individual vent helps to prevent siphoning of water from the trap, which can lead to sewer gases entering the living space and odors being released.

While other venting options can serve broader functions, the key role of an individual vent is to ensure the specific fixture operates efficiently and safely by maintaining its trap seal. This direct association with just one fixture makes it critical for the performance and health of that unit in the plumbing system.