K.21

ITU-T : Publications : Recommendations : K Series

K.1 [Withdrawn] Connection to earth of an audio-frequency telephone line in cable Deleted after its content became technically out of date K.2 [Withdrawn] Protection of repeater power-feeding systems against interference from neighbouring electricity lines Deleted after its content became technically out of date K.3 [Withdrawn] Interference caused by audio-frequency signals injected into a power distribution network Deleted after its content became technically out of date K.4 [Withdrawn] Disturbance to signalling Deleted after its content became technically out of date K.5 Joint use of poles for electricity distribution and for telecommunications K.6 Precautions at crossings K.7 Protection against acoustic shock K.8 Separation in the soil between telecommunication cables and earthing system of power facilities K.9 Protection of telecommunication staff and plant against a large earth potential due to a neighbouring electric traction line K.10 Low frequency interference due to unbalance about earth of telecommunication equipment K.11 Principles of protection against overvoltages and overcurrents K.12 Characteristics of gas discharge tubes for the protection of telecommunications installations K.13 Induced voltages in cables with plastic-insulated conductors K.14 Provision of a metallic screen in plastic-sheathed cables K.15 [Withdrawn] Protection of remote-feeding systems and line repeaters against lightning and interference from neighbouring electricity lines K.16 [Withdrawn] Simplified calculation method for estimating the effect of magnetic induction from power lines on remote-fed repeaters in coaxial pair telecommunication systems Rec. K.16 was withdrawn because it deals only with calculation methods contained in the "Directives - Volume II: Calculating induced voltages and currents in practical cases" without giving any limit K.17 [Withdrawn] Tests on power-fed repeaters using solid-state devices in order to check the arrangements for protection from external interference K.18 Calculation of voltage induced into telecommunication lines from radio station broadcasts and methods of reducing interference K.19 Joint use of trenches and tunnels for telecommunication and power cables K.20 Resistibility of telecommunication equipment installed in a telecommunication centre to overvoltages and overcurrents K.21 Resistibility of telecommunication equipment installed in customer premises to overvoltages and overcurrents K.22 [Withdrawn] Overvoltage resistibility of equipment connected to an ISDN T/S bus K.23 Types of induced noise and description of noise voltage parameters for ISDN basic user networks K.24 Method for measuring radio-frequency induced noise on telecommunications pairs K.25 [Withdrawn] Protection of optical fibre cables This Recommendation was deleted on 2013-01-25 since its requirements have been incoroporated in revised Rec ITU-T K.47 (05/2012) K.26 Protection of telecommunication lines against harmful effects from electric power and electrified railway lines K.27 Bonding configurations and earthing inside a telecommunication building K.28 Parameters of thyristor-based surge protective devices for the protection of telecommunication installations K.29 Coordinated protection schemes for telecommunication cables below ground K.30 [Withdrawn] Self-restoring overcurrent protectors K.31 [Withdrawn] Bonding configurations and earthing of telecommunication installations inside a subscriber's building ITU-T K.31 was deleted on 2008-08-09 after the incorporation of the relevant part of this Recommendation in ITU-T K.73 (2008) K.32 [Withdrawn] Immunity requirements and test methods for electrostatic discharge to telecommunication equipment - Generic EMC Recommendation The content of this Recommendation has been superseded by ITU-T K.43 (1998) and K.48 (2000) K.33 [Withdrawn] Limits for people safety related to coupling into telecommunications system from a.c. electric power and a.c. electrified railway installations in fault conditions ITU-T K.33 was deleted on 2008-08-09 after the incorporation of the relevant information contained in this Recommendation into the revised the Directives Volume VI (2008) K.34 Classification of electromagnetic environmental conditions for telecommunication equipment - Basic EMC Recommendation K.35 Bonding configurations and earthing at remote electronic sites K.36 Selection of protective devices K.37 Low and high frequency EMC mitigation techniques for telecommunication installations and systems - Basic EMC Recommendation K.38 Radiated emission test procedure for physically large systems K.39 Risk assessment of damages to telecommunication sites due to lightning discharges K.40 Protection against LEMP in telecommunications centres K.41 [Withdrawn] Resistibility of internal interfaces of telecommunication centres to surge overvoltages K.42 Preparation of emission and immunity requirements for telecommunication equipment - General principles K.43 Immunity requirements for telecommunication network equipment K.44 Resistibility tests for telecommunication equipment exposed to overvoltages and overcurrents - Basic Recommendation K.Imp44 Implementors' Guide for Recommendation ITU-T K.44 K.45 Resistibility of telecommunication equipment installed in the access and trunk networks to overvoltages and overcurrents K.46 Protection of telecommunication lines using metallic symmetric conductors against lightning-induced surges K.47 Protection of telecommunication lines against direct lightning flashes K.48 EMC requirements for telecommunication equipment - Product family Recommendation K.49 Test requirements and performance criteria for voice terminal telephones subject to disturbance from digital mobile telecommunications systems K.50 Safe limits of operating voltages and currents for telecommunication systems powered over the network K.51 Safety criteria for telecommunication equipment K.52 Guidance on complying with limits for human exposure to electromagnetic fields K.53 [Withdrawn] Values of induced voltages on telecommunication installations to establish telecom and a.c. power and railway operators responsibilities ITU-T K.53 was deleted on 2008-08-09 after the incorporation of the relevant information of this Recommendation in ITU-T K.68 (2008) K.54 Conducted immunity test method and level at fundamental power frequencies El título español fue cambiado por un erratum el 09/08/2002 K.55 Overvoltage and overcurrent requirements for insulation displacement connectors (IDC) terminations K.56 Protection of radio base stations against lightning discharges K.57 Protection measures for radio base stations sited on power line towers K.58 EMC, resistibility and safety requirements and guidance for determining responsibility under co-located information and communication technology installations K.59 EMC, resistibility and safety requirements and procedures for connection to unbundled cables K.60 Emission levels and test methods for wireline telecommunication networks to minimize electromagnetic disturbance of radio services K.61 Guidance on measurement and numerical prediction of electromagnetic fields for compliance with human exposure limits for telecommunication installations K.62 System level radiated emissions compliance using mathematical modelling K.63 Maintaining the suitability of production telecommunications equipment to its intended electromagnetic environment K.64 Safe working practices for outside equipment installed in particular environments K.65 Overvoltage and overcurrent requirements for termination modules with contacts for test ports or surge protective devices K.66 Protection of customer premises from overvoltages K.67 Expected surges on telecommunications and signalling networks due to lightning K.68 Operator responsibilities in the management of electromagnetic interference by power systems on telecommunication systems K.69 Maintenance of protective measures K.70 Mitigation techniques to limit human exposure to EMFs in the vicinity of radiocommunication stations K.71 Protection of customer antenna installations K.72 Protection of telecommunication lines using metallic conductors against lightning - Risk management K.73 Shielding and bonding for cables between buildings K.74 Electromagnetic compatibility, resistibility and safety requirements for home network devices K.75 Classification of interface for application of standards on resistibility and safety of telecommunication equipment K.76 EMC requirements for telecommunication network equipment (9 kHz-150 kHz) K.77 Characteristics of metal oxide varistors for the protection of telecommunication installations K.78 High altitude electromagnetic pulse immunity guide for telecommunication centres K.79 Electromagnetic characterization of the radiated environment in the 2.4 GHz ISM band K.80 EMC requirements for telecommunication network equipment (1 GHz - 6 GHz) K.81 High-power electromagnetic immunity guide for telecommunication systems K.82 Characteristics and ratings of solid-state, self-restoring overcurrent protectors for the protection of telecommunications installations K.83 Monitoring of electromagnetic field levels K.84 Test methods and guide against information leaks through unintentional electromagnetic emissions K.85 Requirements for the mitigation of lightning effects on home networks installed in customer premises K.86 Method for measuring longitudinal conversion loss (9 kHz - 30 MHz) K.87 Guide for the application of electromagnetic security requirements - Overview K.88 EMC requirements for next generation network equipment K.89 Protection of persons inside a structure using telecommunication services provided by metallic conductors against lightning - Risk management K.90 Evaluation techniques and working procedures for compliance with exposure limits of network operator personnel to power-frequency electromagnetic fields K.91 Guidance for assessment, evaluation and monitoring of human exposure to radio frequency electromagnetic fields K.92 Conducted and radiated electromagnetic environment in home networking K.93 Immunity of home network devices to electromagnetic disturbances K.94 Mutual disturbance test method for evaluating performance degradation of converged terminal devices K.95 Surge parameters of isolating transformers used in telecommunication devices and equipment K.96 Surge protective components: Overview of surge mitigation functions and technologies K.97 Lightning protection of distributed base stations K.98 Overvoltage protection guide for telecommunication equipment installed in customer premises K.99 Surge protective component application guide - Gas discharge tubes K.100 Measurement of radio frequency electromagnetic fields to determine compliance with human exposure limits when a base station is put into service K.101 Shielding factors for lightning protection K.102 Parameters of fixed-voltage thyristor overvoltage protector components used for the protection of telecommunication installations K.103 Surge protective component application guide - Silicon PN junction components K.104 Method for identifying the transfer potential of the earth potential rise from high or medium voltage networks to the earthing system or neutral of low voltage networks K.105 Lightning protection of photovoltaic power supply systems feeding radio base stations K.106 Techniques to mitigate interference between radio devices and cable or equipment connected to wired broadband networks and cable television networks K.107 Method for determining the impedance to earth of earthing systems K.108 Joint use of poles by telecommunication and solidly earthed power lines K.109 Installation of telecommunication equipment on utility poles K.110 Lightning protection of the dedicated transformer for radio base station K.111 Protection of surrounding structures of telecommunication towers against lightning K.112 Lightning protection, earthing and bonding: practical procedures for radio base station K.113 Generation of radiofrequency electromagnetic fields (RF-EMF) level maps K.114 Electromagnetic compatibility requirements and measurement methods for digital cellular mobile communication base station equipment K.115 Mitigation methods against electromagnetic security threats K.116 EMC requirements and test methods for radio telecommunication terminal equipment K.Sup1 ITU-T K.91 - Guide on electromagnetic fields and health K.Sup2 ITU-T K.52 - Calculator for equivalent isotropic radiated power as described in Recommendation ITU-T K.52 K.Sup3 Additional criteria to protect telecommunication cabling during a power cross event K.Sup4 Electromagnetic field (EMF) considerations in smart sustainable cities

ITU-T : Publications : Recommendations : K Series : K.21

ITU-T K.21 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Amendment 1 (06/2020)

SERIES K: PROTECTION AGAINST INTERFERENCE

Resistibility of telecommunication equipment installed in customer premises to overvoltages and overcurrents