1.1 This document establishes a designation system of recycled carbon fibres, which may be used as the basis for specification. 1.2 This designation system is applicable to recycled carbon fibres used in polymer composites. 1.3 The types of recycled carbon fibres are differentiated by a designation system based on appropriate levels of the designatory properties: a) tensile modulus of elasticity. b) tensile strength. c) fibre length 1.4 It is not intended to imply that recycled carbon fibres having the same designation will give the same performance. This document does not provide engineering data or data on processing conditions which may be required to specify a material for a particular and/or method of processing. 1.5 In order to specify recycled carbon fibres for a particular application, additional requirements may be given in optional data block 5.