What is the design coefficient for PVC-U pressure pipes?

The design coefficient (safety factor) is used in the design of all pressure systems using plastics pipes. It takes into consideration service conditions as well as properties of the components of a piping system.

This coefficient is illustrated by the following graph:

Graph - Design Coefficient - PVC Pipes for Water Distribution

According to ISO 12162 the minimum value for design coefficients (C min ) are as follows

PVC-U 1.6

PVC-A 1.4

PVC-O 1.4