What is the required size for class 1 and 3 standpipes that are less than 100 feet?

In the context of fire safety and suppression systems, standpipes are crucial for providing water supply to combat fires in buildings. The required sizes for class I and class III standpipes that are less than 100 feet tall are specifically defined in fire codes and standards, which state that a 4-inch diameter for standpipes is necessary.

This 4-inch size allows for adequate water flow rates and pressures to ensure effective firefighting capabilities, especially in taller buildings where reaching the upper floors can be challenging. The diameter is significant because it directly impacts the volume of water that can be delivered. A 4-inch standpipe can carry a sufficient volume of water to meet the demands of fire suppression equipment and hose lines being deployed by firefighters.

In contrast, smaller or larger diameters would either hinder water flow rates or be deemed unnecessary for buildings that do not exceed 100 feet in height. Therefore, adhering to the established requirement of a 4-inch diameter for these classes of standpipes is essential for maintaining efficiency and safety in fire response measures.