1.1 This part of ISO 17855 establishes a system of designation for polyethylene thermoplastic material, which may be used as the basis for specifications.1.2 The types of polyethylene plastics are differentiated from each other by a classification system based on appropriate levels of the designatory propertiesa) density,b) melt mass-flow rate,and on information about the intended application and/or method of processing, important properties, additives, colorants, fillers and reinforcing materials.1.3 This part of ISO 17855 is applicable to all polyethylene homopolymers and to copolymers of ethylene having a content of other 1-olefinic monomers of less than 50 % (mass fraction) and a content of non-olefinic monomers with functional groups up to a maximum of 3 % (mass fraction).It applies to materials ready for normal use in the form of powder, granules or pellets, unmodified or modified by colorants, additives, fillers, etc.This part of ISO 17855 does not apply to masterbatches or to EPM rubber. This part of ISO 17855 also does not apply to PE-UHMW. It should reference to ISO 11542-1 for PE-UHMW.1.4 It is not intended to imply that materials having the same designation give necessarily the same performance. This part of ISO 17855 does not provide engineering data, performance data or data on processing conditions which may be required to specify a material for a particular application and/or method of processing.If such additional properties are required, they shall be determined in accordance with the test methods specified in ISO 1872-2, if suitable.1.5 In order to specify a thermoplastic material for a particular application or to ensure reproducible processing, additional requirements may be given in data block 5 (see Clause 3, introductory paragraph).