Telecommunications Standards: September 2025 Monthly Overview

Looking back at September 2025, the Telecommunications, Audio and Video Engineering sector experienced a substantial wave of standardization activity. In total, five notable standards were published, reflecting a blend of groundbreaking revisions and new methodologies that signal shifts in connectivity, EMC, and cable testing practices. For professionals striving to maintain compliance, continual improvement, and technological leadership, this analytical overview consolidates the month’s most critical developments and facilitates a clear understanding of evolving requirements and industry direction.

Monthly Overview: September 2025

September 2025 was marked by significant progress in the standardization of optical fibre technology, electromagnetic compatibility (EMC), and advanced cable testing methods within the Telecommunications, Audio and Video Engineering field. This period not only brought forward state-of-the-art test procedures but also highlighted the sector’s growing resolve to address challenges in high-density optical interconnection, EMC with an increasing electrification of vehicles, and mechanical reliability of network infrastructure.

Several standards published this month reflected multi-year technical revisions, particularly in optical fibre product specifications and EMC test methodologies for emerging vehicle types and digital systems. There was also acceleration in harmonizing mechanical testing for outdoor fibre installations and enhancing test accuracy for digital cable impedance. These trends suggest a sector focused on raising quality, reliability, and interoperability amid rapidly advancing technology and complex regulatory landscapes.

Compared to typical standards publication activity, the month saw a pronounced emphasis on:

• Comprehensive updates to established optical fibre and cable standards
• Development of new mechanical and time-domain test methodologies
• EMC standards directly addressing new classes of vehicles, devices, and charging infrastructure This comprehensive coverage reflects the industry’s ongoing transition toward higher connectivity densities, robust EMC control, and heightened system dependability.

Standards Published This Month

IEC 60793-2-60:2025 - Optical Fibres for Interconnection Applications

Optical fibres - Part 2-60: Product specifications - Sectional specification for class C single-mode interconnection fibres

IEC 60793-2-60:2025 prescribes the specifications for class C single-mode interconnection fibres—fibre types C1, C2, C3, and C4, as detailed in Table 1 of the standard. These fibres are primarily deployed for internal and cross-connection of optical devices and systems, ensuring dense, reliable optical connectivity vital for advanced communications networks. Published as the second edition, this standard represents a major technical revision of the 2008 edition, aligning with current technological needs and integrating extensive updates to reflect modern deployment and integration practices.

This edition notably replaces the term "intraconnection" with "interconnection", clarifying its applicability and scope. Key feature enhancements include more granular control of fibre optical and mechanical characteristics, such as nominal mode field diameter (MFD) for C1 fibres, primary coating diameter specifications, cable cut-off wavelength requirements, and test parameters for coating strip force. Additional updates address coloured versus uncoloured coatings, the introduction of 200 μm coating diameter options, and new transmission requirements at 1625 nm for C1 fibres.

Targeted toward manufacturers, system integrators, and organizations deploying high-density optical connectivity (e.g., telecom operators, data centre network designers, and fibre-component OEMs), this standard’s strict dimensional, mechanical, and environmental criteria underpin enhanced reliability and interoperability across optical infrastructure.

Key highlights:

• Defines detailed dimensional and mechanical specifications across C1–C4 fibre classes
• Updates critical requirements: coating diameters, cut-off wavelengths, and test forces
• Replaces previous edition; substantial technical and terminological revisions

Access the full standard:View IEC 60793-2-60:2025 on iTeh Standards

IEC 62783-1-2:2025 - Time Domain Test Method for Twinax Cables

Twinax cables for digital communications - Part 1-2: Time domain test method for twinax cables for digital communications - Impedance

IEC 62783-1-2:2025 establishes standardized test methodology for determining the time-domain impedance characteristics of twinaxial (twinax) cables and their assemblies, a critical parameter for high-performance digital communications. The standard details definitions and measurement techniques for several impedance types—differential-mode, common-mode, odd-mode, and even-mode—supporting the design and validation of cables in modern, high-frequency and short-reach applications.

This methodology leverages time domain reflectometry (TDR) and advanced vector analyzers to ensure precise evaluation of impedance uniformity and localized discontinuities, thereby minimizing signal degradation and enhancing transmission integrity. Calibration requirements, equipment guidelines, and measurement procedures are thoroughly defined, making the standard highly relevant to cable manufacturers, test laboratories, and OEMs engaged in data center, industrial automation, and IT system markets.

Key highlights:

• Comprehensive time-domain impedance test procedures (TDR & VNA approaches)
• Facilitates detection of impedance variation and fault localization in twinax cables
• Supports compliance and quality assurance for digital interfaces and assemblies

Access the full standard:View IEC 62783-1-2:2025 on iTeh Standards

EN IEC 55012:2025 - EMC for Vehicles and Devices with Combustion Engines or Traction Batteries

Vehicles, boats and devices with internal combustion engines or traction batteries - Radio disturbance characteristics - Limits and methods of measurement for the protection of off-board receivers

EN IEC 55012:2025 (aligned with CISPR 12:2025) delivers comprehensive limits and methodologies to assess radio disturbance characteristics of vehicles, boats, and equipment powered by either internal combustion engines or traction batteries. The scope encompasses innovations in the electrification of transportation and introduces updated requirements to mitigate electromagnetic interference (EMI) impacting off-board radio receivers.

Key sections address:

• Measurement instrumentation and set-up
• Site requirements and emission limit verification
• Applicability to a broad range of mobility devices and charging scenarios (including vehicles in charging mode and boats)
• Test conditions for both dry and wet environments Testing protocols integrate international best practices and emphasize protection of the radio-frequency spectrum from unintentional emissions, ensuring product interoperability and regulatory alignment across the automotive, marine, and related device markets. The standard’s revised structure, inclusion of emerging transport technologies, and tighter emission controls are particularly pertinent for automotive engineers, compliance officers, EMC consultants, and product designers.

Key highlights:

• Expanded coverage for battery-powered vehicles and charging infrastructure
• Enhanced, harmonized EMI limits and methods for off-board receiver protection
• Indispensable for EMC compliance in automotive and marine industries

Access the full standard:View EN IEC 55012:2025 on iTeh Standards

EN IEC 60794-1-119:2025 - Aeolian Vibration Test Method for Optical Fibre Cables

Optical fibre cables - Part 1-119: Generic specification - Basic optical cable test procedures - Mechanical tests methods - Aeolian vibration, Method E19

EN IEC 60794-1-119:2025 specifies a uniform test procedure for aeolian vibration—wind-induced oscillation—affecting aerial optical fibre cables including ADSS (all-dielectric self-supporting), OPGW (optical ground wire), and OPPC (optical phase conductor). As a major update and partial supersession of earlier testing methods (IEC 60794-1-21, Method E19), this first edition introduces:

• Consistent cable tension maintenance during testing
• Fixed cable loads tailored to cable type (25% RTS for OPGW/OPPC or maximum installation tension for ADSS)
• New metrics: target free loop peak-to-peak antinode amplitude and fatigue/ovality assessments With these enhanced procedures, cable engineers and network deployment teams are better equipped to validate long-term reliability and mitigate mechanical risks in outdoor installations subject to wind-induced strain.

Key highlights:

• Outlines robust, standardized method E19 for aeolian vibration assessment
• Clarifies critical loading, fatigue, and ovality measurement requirements
• Invaluable for telecom operators, fibre cable OEMs, and deployment contractors

Access the full standard:View EN IEC 60794-1-119:2025 on iTeh Standards

IEC 61000-4-27:2000 - EMC Unbalance Immunity Test

Electromagnetic compatibility (EMC) - Part 4-27: Testing and measurement techniques - Unbalance, immunity test

IEC 61000-4-27 addresses the immunity of electronic and electrical equipment (up to 16A per phase) to unbalanced supply voltages—a critical parameter in environments with three-phase power distribution. This standard details laboratory reference conditions, test levels, generator characteristics, and systematic procedures for executing and evaluating immunity tests under controlled three-phase unbalance. The methods apply equally to public and industrial power networks, helping assess product resilience to voltage quality disturbances.

With its structured guidance, the standard is especially relevant for compliance engineers, test laboratories, and manufacturers of telecommunications, audio/video, and ancillary equipment. It underpins requirements for robust system performance in the presence of voltage asymmetry, supporting efforts aligned to holistic electromagnetic compatibility frameworks.

Key highlights:

• Defines reference immunity tests for three-phase unbalanced voltages (equipment up to 16A)
• Structured procedures, equipment specs, and test reporting requirements
• Essential for validating EMC performance of grid-connected electronics and network equipment

Access the full standard:View IEC 61000-4-27:2000 on iTeh Standards

Common Themes and Industry Trends

The September 2025 standards cycle highlighted:

• The convergence of connectivity and reliability priorities: Substantial updates to optical fibre and cable testing standards underscore the industry’s drive toward maximized system uptime, densification, and failure prevention (as seen in IEC 60793-2-60:2025 and EN IEC 60794-1-119:2025).
• Proactive EMC control: Enhanced measurement and emission standards (EN IEC 55012:2025, IEC 61000-4-27:2000) reflect the expanding deployment of electric vehicles and digital infrastructure – phenomena that bring new EMC risks and requirements.
• Precision in test and measurement: IEC 62783-1-2:2025’s time-domain test methods exemplify the sector’s growing reliance on sophisticated tools to ensure digital cable performance in high-frequency, low-latency scenarios.

Notably, industries spanning telecom operators, automotive, industrial automation, data centers, and OEMs were all affected. The month’s publications point to:

• Accelerated electrification (vehicles, boats, devices)
• Growing optical deployment in harsh/outdoor environments
• Heightened interoperability and performance criteria in digital cable assemblies

These intersecting trends reveal a deliberate focus on full-lifecycle quality, from design testability to real-world resilience and regulatory assurance.

Compliance and Implementation Considerations

Organizations impacted by these September 2025 standards should prioritize:

1. Gap Analysis and Specification Review:
   • Assess existing fibre and cable inventories against IEC 60793-2-60:2025 and EN IEC 60794-1-119:2025 specifications.
   • Update EMC program documentation per the latest requirements in EN IEC 55012:2025 and IEC 61000-4-27:2000.
2. Testing and Procurement:
   • Specify time-domain impedance tests (IEC 62783-1-2:2025) for new twinaxial cable qualifications and supply agreements.
   • Verify that all new devices, especially those used in mobile/vehicular contexts, are subjected to updated EMI emission and immunity measures.
3. Training and Awareness:
   • Brief engineering and procurement teams on new requirements, especially mechanical test procedures and EMC evaluation protocols.
4. Timeline and Transition:
   • Monitor transition timelines for withdrawal of previous standards (e.g., replace EN 60794-1-21:2015 with EN IEC 60794-1-119:2025 as harmonized conformity deadlines approach).
   • Keep abreast of evolving legal and market entry requirements driven by new EMC and cable testing standards in target geographies.

For in-depth implementation resources, detailed test protocols, and compliance updates, iTeh Standards (standards.iteh.ai) remains an essential reference.

Conclusion: Key Takeaways from September 2025

September 2025 delivered a potent set of standards in Telecommunications, Audio and Video Engineering that will shape design, quality, and compliance practices for years to come. The major revision of optical fibre and cable mechanical standards, in tandem with refined EMC and impedance test methods, reinforces the sector’s orientation toward reliability, performance, and future-proof interoperability.

Engineers, compliance managers, and procurement leaders should:

• Prioritize review and integration of these revised standards into current projects and quality programs
• Update supplier and laboratory protocols to match the latest EMC and test requirements
• Recognize the interconnected nature of optical, EMC, and mechanical reliability developments in modern network design

Staying current with these standards is crucial—not just for regulatory compliance, but for maintaining a competitive edge and ensuring robust, fault-tolerant communications systems. For detailed specifications and actionable updates, explore each standard in depth using the links provided above, or browse the full collection on iTeh Standards.