This part of ISO 16773 specifies a procedure for the evaluation of the experimental set-up used for carrying out EIS on high-impedance coated samples. For this purpose, dummy cells are used to simulate high-impedance coated samples. On the basis of the equivalent circuits described, this part of ISO 16773 gives guidelines for the use of dummy cells to increase confidence in the test protocol, including making measurements, curve fitting and data presentation. NOTE The measurement of high-impedance coated samples is more crucial with respect to artefacts coming from electromagnetic interferences. Therefore, this part of ISO 16773 considers the aspects for measuring high-impedance samples by using appropriate dummy cells. However, most manufacturers offer complementary dummy cells in the low and medium impedance range. This allows checking the setup in the respective low impedance range.