This document specifies general requirements for sampling, preservation, handling, transport and storage of all water samples including those for biological analyses. It is not applicable to water samples intended for microbiological analyses as specified in ISO 19458, ecotoxicological assays, biological assays and passive sampling as specified in the scope of ISO 5667‑23. This document is particularly appropriate when spot or composite samples cannot be analysed on site and have to be transported to a laboratory for analysis.