ISO/DIS 20468-10

This document provides guidelines for evaluating the dependability of treatment systems for water reuse. The dependability of a treatment system is evaluated mainly from the availabilities of unit processes composing the system facility to perform functional requirements related to water quality performance over a long period of time in operation. The document specifies methodologies for both qualitative and quantitative assessments of availability on a life cycle basis by using two influencing factors, reliability as the ability to prevent a failure, and maintainability as the ability to recover from a failure.