Recommendation ITU-T L.201 (05/2021) Performance requirements for passive optical nodes: Sealed closures for outdoor environments Summary History FOREWORD Table of Contents Introduction 1 Scope 2 References 3 Definitions 3.1 Terms defined elsewhere 3.2 Terms defined in this Recommendation 4 Abbreviations and acronyms 5 Conventions 6 Design characteristics of optical closures 6.1 General requirements 6.2 Design of the closure housing 6.3 Closure materials 6.4 Design of the optical fibre organizer (fibre management system) 6.4.1 Characteristics of the optical fibre organizer (fibre management system) 6.4.2 Configurations of the optical fibre organizers (fibre management systems) 7 Performance evaluation test programme 8 Sample preparation Annex A Performance evaluation criteria A.1 Sealing evaluation A.1.1 Pressure loss during the test A.1.2 Tightness after test A.1.3 Visual appearance A.2 Optical performance evaluation A.2.1 Change in attenuation (change in insertion loss) (static optical stability) A.2.2 Transient loss (dynamic optical stability) Annex B Performance test programme for outdoor subterranean or underground (OS) closures, ground level (OG) closures and above ground (OA) closures B.1 Sealing evaluation B.1.1 Cable axial tension B.1.2 Cable flexure B.1.3 Cable torsion B.1.4 Impact B.1.5 Static load (crush test) (OG and OS only) B.1.6 Vibration (sealing) B.1.7 Waterhead (OS and OG only) B.1.8 Resistance to aggressive media B.1.9 Resistance to detergents (stress cracking) (OS and OG only) B.1.10 Resistance to corrosion (salt fog) B.1.11 Change of temperature (OS) B.1.12 Change of temperature (OA and OG) B.1.13 Re-entries B.1.14 Cable axial compression B.2 Optical performance evaluation B.2.1 Cable axial tension B.2.2 Cable flexure B.2.3 Cable torsion B.2.4 Intervention at a node B.2.5 Vibration (optical) B.2.6 Shock B.2.7 Change of temperature (OS) B.2.8 Change of temperature (OA and OG) Appendix I Product characterization checklist Appendix II Ukrainian experience II.1 Introduction II.2 Dimension and optical characteristics II.2.1 Visual inspection II.2.2 Dimension II.2.3 Bend radius of optical fibres on the cassette II.3 Environmental characteristics II.3.1 Temperature cycling II.3.2 Temperature: Heat durability II.3.3 Temperature: Cold durability II.3.4 Resistance to aggressive media II.3.5 Corrosive atmosphere II.3.6 Water penetration II.3.7 Freeze/thaw II.4 Mechanical characteristics II.4.1 Axial tension II.4.2 Vibration II.4.3 Torsion strength II.4.4 Bending strength II.4.5 Impact II.4.6 Static load II.4.7 Drop II.4.8 Ultraviolet resistance II.5 Field condition tests II.5.1 Re-entry Bibliography <\pre>