ISO 9459-5:2007 specifies a method for outdoor laboratory testing of solar domestic hot-water (SDHW) systems. The method may also be applied for in-situ tests, and also for indoor tests by specifying appropriate draw-off profiles and irradiance profiles for indoor measurements. The system performance is characterized by means of whole-system tests using a ‘black-box’ approach, i.e. no measurements on the system components or inside the system are necessary. Detailed instructions are given on the measurement procedure, on processing and analysis of the measurement data, and on presentation of the test report.