This part of EN 12923 specifies guidelines to be employed when undertaking corrosion tests on advanced technical ceramics. The mechanisms of chemical attack on advanced ceramics are widely varied and depend on the chemical and phase composition and the phase morphology of the material, as well as the corrosive conditions imposed. For any particular engineering application it is usually necessary to model expected conditions of use in order to obtain quantitative data on the ability to withstand the proposed end-use conditions. This European Standard is not restricted to specific material types, nor does it prescribe particular test conditions or a test duration. The actual testing requirements might be very specific, for example, in order to investigate the suitability of a range of materials for a given application in which certain specified conditions occur. This European Standard provides recommended methods for undertaking the assessment of the effect of corrosion and provides guidance on practical issues related to undertaking the tests.