NBN ISO 161-1:2021

This document specifies the nominal outside diameters for metric thermoplastics pipes for the
conveyance of fluids in pressure and non-pressure applications. It also specifies nominal pressure
ratings and minimum required strengths for pressure applications.
It is applicable to smooth thermoplastics pipes of constant circular cross-section along the whole length
of the pipe, whatever their method of manufacture or material of construction.
It is not applicable to pipes designated according to the nominal inside diameter DN/ID.
This document is a basis for standards writers for the selection of nominal diameters and nominal
pressures in the drafting of product standards.