This document defines general requirements, performance requirements and conformity test procedures for automatic sampling devices (samplers) for water and waste water that: sample water and waste water from non-pressurized (i.e. open to atmosphere) channels or vessels; sample over extended periods to collect discrete or composite samples based on time, event or flow proportional sampling. It does not include sampling systems built into online and in-line analysers. The general requirements include functional facilities that samplers need to meet users applications and information that needs to be included in associated documents. The test procedures specify uniform methods to be used when determining key performance characteristics of samplers. All of the test procedures are expected to be carried out under laboratory conditions. It is recognized that for some samplers certain test procedures are not applicable. Statistical procedures are defined for evaluation of the test data. Some example calculations are provided. Specific sample integrity requirements are defined for samplers to be used for the collection of samples of final effluent or influent for the purpose of monitoring the performance of waste water treatment works, as required under the EU s Urban Waste Water Treatment Directive (UWWTD). Samplers to be used for other industrial applications do not need to be assessed against these specific sample integrity requirements. This document does not cover the installation and on-going use of samplers.