For hanging rods that support pipes of 2 1/2 inch NPS or larger, the rod diameter must be at least what size?

The minimum rod diameter for hanging rods that support pipes of 2 1/2 inch NPS or larger is specified to ensure adequate strength and stability for the weight of the pipes being supported. A 1/2-inch diameter rod strikes a balance between being robust enough to support the load while not being excessively heavy or cumbersome to work with.

Using a rod that is 1/2 inch in diameter provides sufficient tensile strength and prevents bending or failing under normal conditions expected for pipes of this size. The selection of a rod diameter larger than 1/2 inch, such as 5/8 inch or 3/4 inch, might offer additional strength but is typically unnecessary for the intended application, potentially leading to increased costs and unnecessary weight.

Therefore, for pipes that are 2 1/2 inches NPS and larger, 1/2 inch is the standard prescribed diameter to effectively ensure safety and structural integrity.