This part of ISO 21072 provides a methodology for establishing quantitative performance data for oil skimmers under moving water conditions, so that the end user can objectively judge, compare and evaluate the design and performance of different skimmer units. The methodology applies to testing in a basin and requires control of oil properties and oil slick characteristics. The method is applicable to all types of skimmers, provided that the equipment dimensions are within the physical limitations of the test basin. The test procedure provides full-scale test results for the unit tested, under controlled conditions, and for one or more classes of oil. NOTE Care will need to be taken when applying the test results to the prediction of skimmer performance under field conditions.