| 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[Withdrawn] Connection to earth of an audio-frequency telephone line in cable
		 Deleted after its content became technically out of date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[Withdrawn] Protection of repeater power-feeding systems against interference from neighbouring electricity lines
		 Deleted after its content became technically out of date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[Withdrawn] Interference caused by audio-frequency signals injected into a power distribution network
		 Deleted after its content became technically out of date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[Withdrawn] Disturbance to signalling
		 Deleted after its content became technically out of date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 telecommunication 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[Withdrawn] Protection of remote-feeding systems and line repeaters against lightning and interference from neighbouring electricity lines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[Withdrawn] Simplified calculation method for estimating the effect of magnetic induction from power lines on remote-fed repeaters in coaxial pair telecommunication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 K.16 was withdrawn because it deals only with calculation methods contained in the "Directives - Volume II: Calculating induced voltages and currents in practical cases" without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[Withdrawn] Tests on power-fed repeaters using solid-state devices in order to check the arrangements for protection from external interference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 electromagnetic compatibility (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 lightning electromagnetic impulses in telecommunication centres
		 
 | 
| K.41 | 
[Withdrawn] Resistibility of internal interfaces of telecommunication centres to surge overvoltages
		 
 | 
| K.42 | General principle for the definition of emission and immunity requirements for telecommunication/ICT equipment
		 
 | 
| K.43 | 
[Withdrawn] Immunity requirements for telecommunication network equipment
		 This Recommendation was superseded on 4 February 2023 as its contents were included in ITU-T K.136, ITU-T K.137 and other K-series Recommendations.
 | 
| K.44 | Resistibility tests for telecommunication equipment exposed to overvoltages and overcurrents - Basic Recommendation
		 
 | 
| K.Imp44 | Implementers' Guide for Recommendation ITU-T K.44 (2008-04)
		 
 | 
| 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 | 
[Withdrawn] EMC requirements for telecommunication equipment - Product family Recommendation
		 This Recommendation was superseded on 4 February 2023 as its contents were included in ITU-T K.136, ITU-T K.137 and other K-series Recommendations.
 | 
| K.49 | Test requirements and performance criteria for voice terminal telephones subject to disturbance from digital mobile telecommunications systems
		 
 | 
| K.50 | Safe limits for operating voltages and currents of 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 | Electromagnetic compatibility, 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 | Electromagnetic compatibility requirements for DC power ports of telecommunication network equipment in frequencies below 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 in the frequency range 1 GHz-40 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 | 
[Withdrawn] EMC requirements for next generation network equipment
		 This Recommendation was superseded on 4 February 2023 as its contents were included in ITU-T K.136, ITU-T K.137 and other K-series Recommendations.
 | 
| 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 operation
		 
 | 
| 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 stations
		 
 | 
| K.111 | Protection of surrounding structures of telecommunication towers against lightning
		 
 | 
| K.112 | Lightning protection, earthing and bonding: Practical procedures for radio base stations
		 
 | 
| K.113 | Generation of radiofrequency electromagnetic field 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 | Electromagnetic compatibility requirements and test methods for radio telecommunication terminal equipment
		 
 | 
| K.117 | Primary protector parameters for the surge protection of equipment Ethernet ports
		 
 | 
| K.118 | Requirements for lightning protection of fibre to the distribution point equipment
		 
 | 
| K.119 | Conformance assessment of radio base stations regarding lightning protection and earthing
		 
 | 
| K.120 | Lightning protection and earthing of a miniature base station
		 
 | 
| K.121 | Guidance on the environmental management for compliance with radio frequency EMF limits for radiocommunication base stations
		 
 | 
| K.122 | Exposure levels in close proximity of radiocommunication antennas
		 
 | 
| K.123 | Electromagnetic compatibility requirements for electrical equipment in telecommunication facilities
		 
 | 
| K.124 | Overview of particle radiation effects on telecommunication systems
		 
 | 
| K.125 | Dangerous effects and protective measures against electromagnetic disturbances when an Internet data centre is co-sited with a high-voltage substation
		 
 | 
| K.126 | Surge protective component application guide - High frequency signal isolation transformers
		 
 | 
| K.127 | Immunity requirements for telecommunication equipment in close proximity use of wireless devices
		 
 | 
| K.128 | Surge protective component application guide - metal oxide varistor (MOV) components
		 
 | 
| K.129 | Characteristics and ratings of silicon PN junction voltage clamping components used for the protection of telecommunication installations
		 
 | 
| K.130 | Neutron irradiation test methods for telecommunication equipment
		 
 | 
| K.131 | Design methodologies for telecommunication systems applying soft error measures
		 
 | 
| K.132 | Electromagnetic compatibility requirements of electromagnetic disturbances from lighting equipment located in telecommunication facilities
		 
 | 
| K.133 | Electromagnetic environment of body-worn equipment in the 2.4 GHz and 13.56 MHz industrial, scientific and medical band
		 
 | 
| K.134 | Protection of small-size telecommunication installations with poor earthing conditions
		 
 | 
| K.135 | Technical parameters for residual current operated protective devices with automatic reclosing feature for telecom applications
		 
 | 
| K.136 | Electromagnetic compatibility requirements for radio telecommunication equipment
		 
 | 
| K.137 | Electromagnetic compatibility requirements and measurement methods for wireline telecommunication network equipment
		 
 | 
| K.138 | Quality estimation methods and application guidelines for mitigation measures based on particle radiation tests
		 
 | 
| K.139 | Reliability requirements for telecommunication systems affected by particle radiation
		 
 | 
| K.140 | Surge protective component application guide - Fuses
		 
 | 
| K.141 | Electromagnetic compatibility requirements for information perception equipment
		 
 | 
| K.142 | Lightning protection and earthing of video surveillance systems
		 
 | 
| K.143 | Guidance on safety relating to the use of surge protective devices and surge protective components in telecommunication terminal equipment
		 
 | 
| K.144 | Surge protective component application guide - Self-restoring thermally activated overcurrent protectors
		 
 | 
| K.145 | Assessment and management of compliance with radio frequency electromagnetic field exposure limits for workers at radiocommunication sites and facilities
		 
 | 
| K.146 | Interference management for telecommunication transmissions over copper lines for signals other than speech
		 
 | 
| K.147 | Protection of digital ports connected to balanced pairs of conductors
		 
 | 
| K.148 | Multiservice surge protective device application guide
		 
 | 
| K.149 | Passive intermodulation test methods of array antenna systems in mobile communication systems
		 
 | 
| K.150 | Information of semiconductor devices required for the design of telecommunication equipment applying soft error mitigation measures
		 
 | 
| K.151 | Electrical safety and lightning protection of medium voltage input and up to ±400 VDC output power system in ICT data centres and telecommunication centres
		 
 | 
| K.152 | Electromagnetic compatibility requirements for power equipment in telecommunication facilities
		 
 | 
| K.153 | Guidance on determining the compliance boundaries (exclusion zones) of radio transmitter installations
		 
 | 
| K.154 | Operating telecommunication facilities using lightning strikes data obtained from lightning location systems
		 
 | 
| K.155 | Performance requirements and test methods for surge protective modules used in AC power ports of telecommunication equipment
		 
 | 
| K.156 | Time and spatial averaging in RF-EMF exposure assessment
		 
 | 
| K.157 | Electromagnetic compatibility requirements and test methods for satellite communication terminal equipment
		 
 | 
| K.158 | Practical guidance for protection of the indoor distribution system for mobile communication in large-scale physical buildings
		 
 | 
| K.Sup30 | ITU-T K.118 - Requirements for lightning protection of fibre to the distribution point equipment - Overview
		 
 | 
| K.Sup27 | The 100 kHz ring wave generator
		 
 | 
| 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 | ITU-T K.20, K.21, K.45, K.82 - Additional criteria to protect telecommunication cabling during a power cross event
		 
 | 
| K.Sup4 | ITU-T K.91 -  Electromagnetic field considerations in smart sustainable cities
		 
 | 
| K.Sup5 | ITU-T K.81 - Estimation examples of the high-power electromagnetic threat and vulnerability for telecommunication systems
		 
 | 
| K.Sup6 | ITU-T K.115 - Measuring shielding effectiveness using normalized site attenuation in free space
		 
 | 
| K.Sup7 | ITU-T K.44 - AC supply configurations
		 
 | 
| K.Sup8 | Resistibility analysis of 5G systems
		 
 | 
| K.Sup9 | 5G technology and human exposure to radiofrequency electromagnetic fields
		 
 | 
| K.Sup10 | Analysis of electromagnetic compatibility aspects and definition of requirements for 5G mobile systems
		 
 | 
| K.Sup11 | ITU-T K.131 - Soft error measures for field programmable gate arrays
		 
 | 
| K.Sup12 | ITU-T K.51 - Potential hazards of narrow pin spacing in connectors
		 
 | 
| K.Sup13 | Radiofrequency electromagnetic field (RF-EMF) exposure levels from mobile and portable devices during different conditions of use
		 
 | 
| K.Sup14 | The impact of RF-EMF exposure limits stricter than the ICNIRP or IEEE guidelines on 4G and 5G mobile network deployment
		 
 | 
| K.Sup15 | ITU-T K.20, K.21 and K.44 - Internal DC powering interface surge testing factors
		 
 | 
| K.Sup16 | Electromagnetic field compliance assessments for 5G wireless networks
		 
 | 
| K.Sup17 | ITU-T K.44 - Test conditions and methods information
		 
 | 
| K.Sup18 | ITU-T K.44 - Causes of telecommunication system overvoltage and overcurrent conditions and their expected levels
		 
 | 
| K.Sup19 | Electromagnetic field (EMF) strength inside underground railway trains
		 
 | 
| K.Sup20 | ITU-T K.91 - Supplement on radiofrequency exposure evaluation around underground base stations
		 
 | 
| K.Sup21 | ITU-T K.21 - Rationale for setting resistibility requirements of telecommunication equipment installed in customer premises against lightning
		 
 | 
| K.Sup22 | ITU-T K.45 - Rationale for setting resistibility requirements of telecommunication equipment installed in the access and trunk networks against lightning
		 
 | 
| K.Sup23 | Ethernet port surge voltages and currents
		 
 | 
| K.Sup24 | ITU-T K.20 - Rationale for setting resistibility requirements of telecommunication equipment installed in a telecommunication centre against lightning
		 
 | 
| K.Sup25 | ITU-T K.117 - Long reach single twisted-pair Ethernet resistibility testing
		 
 | 
| K.Sup26 | ITU-T K.114 - Analysis of electromagnetic compatibility requirements and test methods of 5G active antenna system base stations
		 
 | 
| K.Sup28 | Electric shock and related terms and definitions
		 
 | 
| K.Sup29 | Electromagnetic field strength inside and outside of electric vehicles using wireless power transfer technology
		 
 | 
| K.Sup31 | ITU-T K.118 - Requirements for lightning protection of fibre to the distribution point equipment - Modelling earth potential rise
		 
 | 
| K.Sup32 | Case studies of radio frequency- electromagnetic field (RF-EMF) assessment
		 
 |