IEC/PAS 61753-1-3:2009(E) is a Publicly Available Specification (PAS) that defines the minimum initial performance, test and measurement requirements and severities which a single-mode connector or cable assembly must satisfy in order to be categorized as meeting IEC Category I (industrial environment). Category I is an addition to environmental categories C, U, O, E described in IEC 61753-1 and the MICE methodology described in ISO/IEC 24702.