This part of IEC 61753 defines the minimum initial test and measurement requirements and severities which single-mode fibre optic connectors terminated as a pigtail or a patchcord satisfy in order to be categorized as meeting the IEC standard category C (controlled environment), as defined in IEC 61753-1.
If tests were performed on the connectors terminated as pigtails or patchcords for categories OP+HD, OP+, OP, OPHD, or CHD and the product passed, the product will be automatically qualified or categorized as meeting the IEC standard for category C.