What does the acronym PE stand for when referencing certain types of pipe?

The acronym PE when referencing certain types of pipe stands for Polyethylene. This material is widely used in water distribution systems due to its excellent resistance to corrosion, chemical degradation, and its flexibility, which makes it easier to install compared to rigid piping materials. Polyethylene pipes are available in various grades and are often utilized in applications such as potable water distribution, irrigation, and sewer systems, thanks to their durability and long service life.

In contrast, the other materials listed in the choices serve different purposes and have distinct properties that do not align with the commonly used piping in water distribution systems. For example, Polyester is mainly used in textiles and composites, Polystyrene is used for insulation and packaging but not typically for pipes, and Polypropylene, while also a polymer used in piping systems for certain applications, does not have the same widespread use for water distribution as Polyethylene.