This International Standard specifies methods for testing hydraulic valves which are used for the control of flow or pressure in a circuit in order to determine their steady-state and dynamic performance. Requirements for test installations and procedures, measurements and presentation of results are specified. This International Standard does not establish limits of performance since the suitability of the valve for its intended purpose should be agreed between the manufacturer and the user. Accuracy of measurement is divided into three classes (A, B and C) which are explained in annex A. Guidance as to the use of practical units for the presentation of results is given in annex B. Proportional control valves are not dealt with in this International Standard. Electrohydraulic servovalves are dealt with in ISO 6404.