This part of IEC 62333 provides terms and definitions for an electromagnetic noise suppression sheet for digital devices and equipment used in a frequency range of between 30 MHz to 30 GHz, and refers to the influence on the signal by usage of a noise suppression sheet. Guidance is also given for uniform presentation of the properties of a noise suppression sheet, intended for use in manufactures’ technical data. A noise suppression sheet is distinguished from RF wave absorbers used in free space. This part of IEC 62333 is limited to establishing terms and definitions. It constitutes a concise reference for Part 2 of the standard. Part 2 specifies in detail the measurement of parameters defined in Part 1. The two parts of IEC 62333 are therefore closely related, and are intended to be used together. NOTE This standard also specifies the influences on signal lines by using these sheets.