1.1 This specification covers polyethylene (PE) pipe made in standard thermoplastic pipe dimension ratios and pressure rated for water (see appendix). Included are criteria for classifying PE plastic pipe materials and PE plastic pipe, a system of nome This specification covers polyethylene (PE) pipe made in standard thermoplastic pipe dimension ratios and pressure rated for water. Polyethylene plastics used to make pipe meeting the requirements of this specification are categorized in two criteria: