What is the correct position for a vent stack when installed for a plumbing fixture?

The correct position for a vent stack when installed for a plumbing fixture is vertical. A vent stack's primary function is to allow air to enter the plumbing system, which helps to maintain neutral air pressure and prevents the trap seals from being siphoned out. This is essential for the proper drainage and functionality of the plumbing system.

When installed vertically, the vent stack effectively allows sewer gases to escape and simultaneously ensures that air can enter the system to promote efficient drainage. It helps maintain an adequate flow of water and waste through the pipes and prevents problems like slow drainage or backup, which can occur if the venting is inadequate.

Other positions, such as horizontal or at an angle, may hinder proper airflow and could lead to blockages or ineffective venting. A vertical position facilitates the best upward movement of gases while also accommodating the necessary flow of air to support the plumbing system's performance.