This European Standard specifies the conditions for measurement of tensile properties of single filament of ceramic fibres at high temperatures in air or inert atmosphere (vacuum or controlled atmosphere). The method applies to continuous ceramic filaments taken from tows, yarns, staple fibre, braids and knitting, that have strain to fracture less or equal to 5 % and show linear elastic behaviour to fracture. The method does not apply to testing for homogeneity of strength properties of fibres, nor does it assess the effects of volume under stress. Statistical aspects of fibre failure are not included. Two methods are proposed depending on the temperature of the filament end: Hot end method: this method allows determination of tensile strength, of Young\'s modulus and of the stress strain curve. NOTE 1 Current experience with this technique is limited to 1 300 °C, because of the application temperature of ceramic glue. Cold end method. NOTE 2 This method is limited to 1 700 °C in air and 2 000 °C in inert atmosphere because of the limits of furnaces.