ISO 16075-4:2016 provides recommendations regarding:
monitoring the quality of treated wastewater (TWW) for irrigation;
monitoring irrigated plants;
monitoring the soil with regard to salinity;
monitoring natural water sources in neighbouring environments;
monitoring the quality of water in storage reservoirs.
It puts emphasis on sampling methods and their frequency. Regarding the methods of analysis, ISO 16075-4:2016 refers to standard methods or, where not available, to other bibliographical references.