October 2025 Review: Key Standards in Metrology and Measurement—Physical Phenomena

Professionals in metrology and measurement witnessed a notable set of standardizations in October 2025, shaping how industries address measurement accuracy, diagnostic reliability, and compliance in diverse physical phenomena. This monthly overview synthesizes five significant standards released during the period, reflecting wide-ranging progress—from auditory evoked potential equipment and statistical robustness in measurements to electrostatic ionization, predictive machine maintenance, and rapid radioactivity screening. By taking a step back, this article helps engineers, laboratory managers, regulatory specialists, and researchers understand the collective direction of standardization efforts, identify what they may have missed, and stay proactive with implementation in their own organizations.

Monthly Overview: October 2025

Looking back at October 2025, standardization activity in Metrology and Measurement—Physical Phenomena spanned several technical domains. Five key standards were published by CEN, ISO, and IEC, each addressing prevalent and emerging industry demands:

• Precision and robustness in measurement methodologies were prioritized, streamlining statistical analysis and outlier handling.
• Performance and safety in electroacoustic and electrostatic instruments were reinforced, including updated requirements for auditory diagnostics and ionizer test methods.
• Condition monitoring for complex machinery continued its evolution, with guidelines emphasizing unified communication and diagnostic modeling.
• Environmental and field detection of radioactivity saw advancements in rapid gamma-ray screening, crucial for emergency situations and routine monitoring alike.

Compared to previous months, October 2025 exhibited a strong focus on harmonizing precision protocols and broadening applicability—signaling a market-wide commitment to reproducibility, interoperability, and flexible deployment (including point-of-need and field diagnostics). These developments point toward a more integrated and responsive metrology ecosystem, addressing multidisciplinary challenges across manufacturing, healthcare, environmental safety, and technical services.

Standards Published This Month

EN IEC 60645-7:2025 – Instruments for the Measurement of Auditory Evoked Potentials

Electroacoustics – Audiometric Equipment – Part 7: Instruments for the Measurement of Auditory Evoked Potentials

This edition replaces EN 60645-7:2010 and EN IEC 60645-3:2020, integrating substantial updates to specification and test requirements. It applies to devices intended for measuring auditory evoked potentials—from the inner ear through the central auditory pathways—utilizing short-duration acoustic or vibratory stimuli. The standard defines: (i) essential manufacturer specifications, (ii) specific performance requirements for both screening and clinical instruments, and (iii) methods for characterizing audiometric reference and test signals.

This ensures that measurements from different compliant instruments are consistent and reproducible when performed under comparable test conditions. Notably, the scope excludes evoked response measurements based on electrical stimuli. The revision brings the specification of instruments and test signals into a single document, aligning with updates across the IEC 60645 series.

Who should comply:

• Audiology device manufacturers and clinical practitioners
• Medical electrical equipment compliance teams
• Accredited audiometric laboratories

Key highlights:

• Integrates device and test signal requirements for a consolidated compliance path
• Specifies new methods for measuring and describing reference signals and test stimuli
• Aligns uncertainty, safety, and performance marking with the latest IEC/ISO standards

Access the full standard:View EN IEC 60645-7:2025 on iTeh Standards

ISO 5725-5:2025 – Alternative Precision Determination Methods

Accuracy (Trueness and Precision) of Measurement Methods and Results – Part 5: Alternative Methods for the Determination of the Precision of a Standard Measurement Method

This edition introduces robust, outlier-tolerant statistical methodologies for determining the precision of measurement methods, moving beyond traditional outlier exclusion techniques. It details algorithms (such as Algorithm A and S, as well as the Q and Hampel methods) designed to analyze data without subjective judgment on outlier exclusion, thereby strengthening the objectivity and repeatability of results across laboratories and experimental designs.

The guidance is particularly relevant for laboratories participating in collaborative studies, process industries seeking to evaluate method robustness, and any organization grappling with heterogeneous materials or datasets where traditional techniques may inflate variance or introduce bias.

Key highlights:

• Details step-by-step procedural guidance for robust statistical analysis
• Supplants outlier removal with mathematically principled handling of data irregularities
• Provides improved tools for split-level designs and precision studies involving heterogeneous samples

Access the full standard:View ISO 5725-5:2025 on iTeh Standards

EN IEC 61340-4-7:2025 – Electrostatics: Test Methods for Ionization

Electrostatics – Part 4-7: Standard Test Methods for Specific Applications – Ionization

Superseding the 2017 version, this third edition updates test methods for evaluating and selecting air ionization equipment—essential for controlling static electricity in sensitive environments such as electronics manufacturing, cleanrooms, and hazardous locations. The document describes standardized techniques to measure ionizer offset voltage and charge decay/neutralization times, allowing for objective performance benchmarking in both manufacturer R&D and user acceptance testing.

It also provides detailed safety considerations and encourages adaptation of test methods for application-specific or periodic verification scenarios. While EMI measurements and ordnance-related applications are excluded, the standard offers a foundation for consistent reporting and regulatory alignment in static discharge-sensitive industries.

Key highlights:

• Updated figures and definitions supporting new device types (e.g., pulsed DC systems)
• Expanded information on theoretical background and error sources
• Enhanced guidance on safety, particularly concerning electrical, ozone, and radiation risks

Access the full standard:View EN IEC 61340-4-7:2025 on iTeh Standards

ISO 13379-1:2025 – Condition Monitoring and Diagnostics of Machine Systems

Condition Monitoring and Diagnostics of Machine Systems – Data Interpretation and Diagnostics Techniques – Part 1: General Guidelines

This extensively revised edition unifies concepts and technical requirements for condition monitoring and diagnostics applicable to any machine system where operational parameters inform system health. The document clarifies terminology, presents diagnostic models—both data-driven and knowledge-based—and guides users in selecting and developing effective diagnostic approaches. It provides frameworks for integrating failure mode symptoms analysis (FMSA), incorporating machine and maintenance history, and documenting diagnostics in a structured report for effective decision support.

Applicable across manufacturing, process, and transportation sectors, the guideline aids both developers and users of diagnostic systems, ensuring more reliable machine availability and reducing downtime through informed predictive maintenance.

Key highlights:

• Details unified approaches for anomaly detection, hypothesis formation, and hypothesis testing
• Introduces enhanced FMSA analysis and model selection strategies
• Includes best practice annexes with practical diagnostic reports and model applications

Access the full standard:View ISO 13379-1:2025 on iTeh Standards

EN ISO 19581:2025 – Rapid Screening for Gamma-Emitting Radionuclides

Measurement of Radioactivity – Gamma Emitting Radionuclides – Rapid Screening Method Using Scintillation Detector Gamma-Ray Spectrometry (ISO 19581:2025)

This standard specifies practical test methods allowing rapid, in-field quantification of gamma-emitting radionuclides (such as ⁱ³¹I, ¹³⁴Cs, ¹³⁷Cs) in a wide range of solid or liquid samples. Employing readily deployable scintillation gamma spectrometers—more accessible than laboratory-grade HPGe detectors—this guidance empowers emergency response teams, environmental monitoring units, and food and feed safety laboratories to perform high-throughput screening immediately after sample collection.

While it does not cover sampling procedures or OIL threshold establishment, it details sample handling, measurement, calibration, and result interpretation procedures, providing qualitative and near-quantitative screening results for incident mitigation or routine surveillance.

Key highlights:

• Field-friendly methodology with flexible laboratory requirements
• Enables efficient response during radiological emergencies or routine screening of food, soil, or industrial materials
• Defines calibration, operation, and result reporting for portable scintillation detectors

Access the full standard:View EN ISO 19581:2025 on iTeh Standards

Common Themes and Industry Trends

Several pivotal trends emerged from the October 2025 standardization activity:

• Emphasis on statistical rigor and data robustness. ISO 5725-5:2025 pushed for outlier-resistant analysis, directly supporting reproducibility in test laboratories and research programs across disciplines.
• Trait toward unified guidelines and systematic approaches. ISO 13379-1:2025 and EN IEC 60645-7:2025 both sought to consolidate requirements and harmonize methodologies, whether in machine diagnostics or audiometric instrumentation.
• Operational adaptability and rapid response. EN ISO 19581:2025 stands out for facilitating quick, reliable results in the field, whether for environmental emergencies or routine quality assurance.
• Heightened attention on safety and compliance. EN IEC 61340-4-7:2025 updated or clarified explicit safety requirements, recognizing the evolving risk profiles of electrostatic ionization devices and the environments in which they operate.
• Cross-disciplinary impact. These standards affect clients across healthcare, environmental monitoring, electronics manufacturing, and industrial maintenance, underscoring the centrality of robust, comparable measurement practices in managing risk, quality, and strategic planning.

Compliance and Implementation Considerations

Organizations subject to these October 2025 standards should consider the following action items and strategies:

• Gap assessments: Review existing protocols and equipment against the new/revised performance and reporting requirements, especially for audiometric, electrostatic, and radiological instrumentation.
• Training and procedural updates: Equip technical staff with updated measurement and diagnostic methodologies, leveraging new toolkits for statistical robustness or field measurement.
• Procurement evaluations: Ensure new equipment or systems—such as ionizers or gamma spectrometers—are specified and acquired with explicit reference to these updated standards.
• Inter-laboratory calibration and validation: Where applicable, incorporate robust statistical methods from ISO 5725-5:2025 into collaborative or proficiency testing schemes to ensure cross-site fidelity.
• Documentation and audit readiness: Update internal quality manuals and testing documentation, referencing the latest editions and accommodating any new data recording or reporting stipulations.

Suggested approach for implementation:

1. Identify all processes and assets affected by these standards
2. Engage technical and compliance teams for cross-functional review
3. Update or acquire compliant equipment/software where needed
4. Conduct staff training
5. Adjust documentation, reporting practices, and audit procedures
6. Set an internal compliance timeline, referencing withdrawal dates for superseded standards

Leverage resources such as the iTeh Standards platform for easy-access to full texts and support materials.

Conclusion: Key Takeaways from October 2025

October 2025 marked a crucial month for the Metrology and Measurement—Physical Phenomena community, providing both evolutionary and revolutionary updates across standardization domains. The standards on robust statistical analysis (ISO 5725-5), auditory evoked potential measurement (EN IEC 60645-7), and rapid radionuclide screening (EN ISO 19581) are likely to have the most immediate operational effects.

For professionals in product development, quality assurance, calibration laboratories, and environmental monitoring, the message is clear: staying current with standards is vital not only for compliance and accreditation, but for ensuring measurement accuracy, risk management, and decision-making effectiveness. Organizations are advised to systematically review these new standards, integrate their requirements, and invest in staff development to maximize benefits from the industry's ongoing commitment to harmonized excellence.

Browse all referenced standards and access the full documentation on iTeh Standards. Ensure you are prepared for the evolving landscape of metrology and measurement.