ISO 17138:2014 describes a method for the determination of the flexural strength of ceramic matrix composite materials with continuous fibre reinforcement, under three-point or four-point bend at room temperature. This method applies to all ceramic matrix composites with a continuous fibre reinforcement, unidirectional (1D), bidirectional (2D), and tridirectional xD with (2 < x ≤ 3) as defined in CEN/ TR 13233, loaded along one principal axis of reinforcement.