Illinois Plumbing Code Practice

How far above a floor or horizontally from the nearest vented connection must a dead end in a drainage system have a vented connection to the outside atmosphere if intended for future connection?

1. 1 foot above, 4 feet horizontally

2. 2 feet above, 5 feet horizontally

3. 2 feet above, 10 feet horizontally

4. 3 feet above, 15 feet horizontally

The correct answer is: 2 feet above, 10 feet horizontally

The correct answer is that a dead end in a drainage system must have a vented connection to the outside atmosphere 2 feet above and 10 feet horizontally from the nearest vented connection. This is consistent with the Illinois Plumbing Code regulations, which are designed to ensure proper ventilation of the drainage system. Ventilation is crucial because it prevents the build-up of harmful gases and ensures proper drainage by allowing air to enter the system. The specified distance helps maintain an effective air flow and minimizes the risk of siphoning or vacuum conditions that can obstruct drainage. Other options suggest varying heights and horizontal distances that do not align with the established guidelines in the code, thereby failing to provide adequate ventilation or potentially compromising the drainage system's performance and safety. The combination of 2 feet and 10 feet is optimal for addressing these concerns specifically for future connections.