This part of ISO 14527 establishes a data block system for the designation of urea-formaldehyde and urea/melamine-formaldehyde powder moulding compounds (UF- and UF/MF-PMCs). The various types of UF- and UF/MF-PMC are differentiated from each other by a classification system based on information about the filler/reinforcement type and content, the intended method of processing, any special properties and those of the special properties used specifically for designation purposes (designatory properties). This part of ISO 14527 is applicable to all UF- and UF/MF_PMCs ready for normal use in the form of powder, granules or ground material. It is not intended to imply that materials having the same designation necessarily give the same performance. This part of ISO 14527 does not provide engineering data, performance data or data on processing conditions which may require 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 14527-2, if suitable. Whenever general requirement data, as covered by ISO 14527-3, need to be indicated, this is also done using this data block system. To ensure that code-letters and code-numbers remain unambiguous, and to avoid conflicts within the system, any new code-letters or code-numbers for use in data block 1, 2 or 3 shall be approved before use by the secretariats of ISO/TC 61/SC 1, SC 12 and SC 13.