IEC 60793-2-40:2021作为IEC 60793-2-40:2021 RLV提供，其中包含国际标准及其红线版本，显示了与上一版本相比技术内容的所有变化。IEC 60793-2-40:2021适用于A4类多模光纤以及相关子类A4a、A4b、A4c、A4d、A4e、A4g、A4h和A4i。这些纤维具有塑料芯和塑料包层，并且可以具有阶梯折射率、多阶梯折射率或渐变折射率轮廓。光纤用于信息传输设备和采用类似光传输技术的其他应用，以及光纤电缆。表1总结了这些纤维的一些显著特性和应用。这第五版取消并取代了2015年出版的第四版。本版构成技术修订版。与上一版相比，此版本包括以下重大技术变更: -修订A4a.2的NA范围； -增加一个新的子类A4i； -删除A4f小类和附件F。

IEC 60793-2-40:2021 is available as IEC 60793-2-40:2021 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition.

IEC 60793-2-40:2021 is applicable to category A4 optical multimode fibres and the related subcategories A4a, A4b, A4c, A4d, A4e, A4g, A4h and A4i. These fibres have a plastic core and plastic cladding and may have step-index, multi-step index or graded-index profiles. The fibres are used in information transmission equipment and other applications employing similar light transmitting techniques, and in fibre optic cables. Table 1 summarizes some of the salient characteristics and applications of these fibres. This fifth edition cancels and replaces the fourth edition published in 2015. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- revision of NA range of A4a.2;
- addition of a new subcategory A4i;
- deletion of the subcategory A4f and of Annex F.