What is the standard riser size for a 5-1/4" fire hydrant?

The standard riser size for a 5-1/4" fire hydrant is a 6" ductile iron riser. This size is chosen to ensure that there is sufficient water flow and pressure available to effectively operate the hydrant during firefighting activities. A 6" riser provides the necessary capacity to maximize the flow rate, helping firefighters access the volume of water needed quickly and efficiently.

Using a riser that is too small would restrict water flow, diminishing the effectiveness of the hydrant when it's needed most. Conversely, larger riser sizes, such as 8" or 10", may lead to unnecessary costs and complications without providing additional functional benefits for a hydrant of that size.