July 2025 in Review: Key Metrology and Measurement Standards Published

Looking back at July 2025, the metrology and measurement sector saw the publication of several pivotal standards focused on physical phenomena. This monthly overview analyzes five key international documents released in the period—spanning field test procedures for geodetic instrumentation, updated guidance for ultrasonic surgical systems, methods for radioactivity measurement, and more. For industry professionals, compliance specialists, engineers, and researchers, this retrospective provides not just an inventory but also context and insight into the technical and strategic directions shaping the field. Understanding these developments is essential for maintaining best practices, achieving operational excellence, and aligning with the evolving regulatory landscape.

Monthly Overview: July 2025

July 2025 was characterized by a notable emphasis on both the accuracy of field measurements and the refinement of laboratory procedures throughout the metrology and measurement sector. The five standards published this month serve the diverse needs of quality assurance in surveying, environmental monitoring, medical technology, and process engineering. Two new parts in the ISO 17123 series significantly broadened procedures for in-situ testing of geodetic and surveying equipment, now including advanced GNSS applications and rotating lasers. Fluid flow measurement received a technical refresh with the revision of ISO 3966, while methodologies for detecting beta-emitting radionuclides in various matrices were strengthened by the update to ISO 19361. Rounding out the month, EN IEC 61847 delivered a substantial revision for ultrasonic surgical systems, reflecting both recent technological advances and new safety requirements.

Compared to previous months, July 2025 evidenced a strong alignment with evolving industry requirements—particularly in digitalization, system integration, and a growing need for traceable, uncertainty-quantified results. The prominence of field verification and updated uncertainty evaluation procedures suggests a shift toward more robust, user-friendly, and application-oriented standards across disciplines.

Standards Published This Month

ISO 17123-11:2025 - GNSS Instruments Field Test Procedures

Optics and optical instruments – Field procedures for testing geodetic and surveying instruments – Part 11: GNSS instruments

The eleventh part of ISO 17123 introduced a standardized, multistage process for field verification of Global Navigation Satellite System (GNSS) instruments. Applicable to a spectrum of geodetic and surveying systems, this standard defines field procedures focused on verifying whether specific GNSS-based measurement methods and instruments deliver location-specific uncertainty levels that meet operational requirements. Covering both the latest integrated GNSS receivers and traditional systems, the procedures are built on a comparative methodology involving three-dimensional spatial coordinates checked against reference values.

ISO 17123-11 outlines practical steps for performing daily checks, allowing users to gauge instrument performance under actual field conditions—including the influence of atmospheric and site-specific factors—without specialized equipment. The versatility extends to any GNSS signal or data stream, reflecting rapid advances in commercially available devices. The standard introduces delimitation criteria to give users flexibility in application and enables regular in-field verification at minimal cost, supporting ongoing quality assurance objectives for engineering, land management, and infrastructure projects.

Key highlights:

• Multistage, uncertainty-driven field verification procedures for GNSS instruments
• Universal applicability regardless of GNSS hardware or satellite system
• Designed for routine, cost-efficient field use to maintain measurement confidence

Access the full standard:View ISO 17123-11:2025 on iTeh Standards

ISO 19361:2025 - Beta Emitters via Liquid Scintillation Counting

Measurement of radioactivity – Determination of beta emitters activities – Test method using liquid scintillation counting

This updated international standard provides a technically robust framework for measuring the activity concentrations of beta-emitting radionuclides in liquid and solid samples using liquid scintillation counting. Modeled for laboratory analysts engaged in environmental monitoring, industrial hygiene, regulatory compliance, and nuclear decommissioning, the document stipulates detailed requirements for sample preparation, choice of scintillation cocktails, calibration procedures, background determination, efficiency calculation, quench correction, and results evaluation.

A major focus is given to recognizing and minimizing interference from other radioactive species (alpha, gamma, or other beta emitters) via appropriate sample pre-treatment when necessary. The measurement protocols apply broadly to a range of concentrations (from 1 Bq/l to 10^6 Bq/l for liquids), ensuring that laboratories can match the operational range of the instruments while maintaining data integrity. ISO 19361:2025 supersedes previous editions, harmonizing methods in alignment with contemporary uncertainty evaluation principles (notably, the ISO 11929 family for expressing results), thus supporting comparability in results and suitability for laboratory accreditation.

Key highlights:

• Detailed guidance for both liquid and solid sample matrices
• Enhanced emphasis on uncertainty, interference minimization, and calibration
• Updated to match current best practices and regulatory demands

Access the full standard:View ISO 19361:2025 on iTeh Standards

EN IEC 61847:2025 - Ultrasonics Surgical Systems Output Measurement

Ultrasonics – Surgical systems – Measurement and declaration of the basic output characteristics

This technical revision, aligning IEC and European requirements, supersedes earlier versions and delivers significant updates to the performance characterization of ultrasonic surgical equipment. EN IEC 61847:2025 is critical for manufacturers, test laboratories, and regulatory authorities concerned with ultrasonic instruments operating from 20 kHz to 120 kHz for tasks such as tissue fragmentation, emulsification, and precise cutting.

Key changes include raising the upper test frequency to 120 kHz and updating the normative measurement methodology—now favoring the hydrophone over calorimetry given its enhanced accuracy and applicability. The document spells out test conditions, calibration approaches, and data reporting needs for a wide array of ultrasonic system configurations, addressing directivity, tip vibration, cavitation effects, and complex operational modes. As medical device regulators scrutinize safety and efficacy, EN IEC 61847:2025 serves as a comprehensive benchmark for device development, performance verification, and market clearance.

Key highlights:

• Major technical revision including updated test frequencies and measurement techniques
• New and clarified requirements for multi-mode devices, cavitation, and directivity assessment
• Aligned with contemporary international regulatory and market expectations

Access the full standard:View EN IEC 61847:2025 on iTeh Standards

ISO 17123-6:2025 - Field Testing of Rotating Lasers

Optics and optical instruments – Field procedures for testing geodetic and surveying instruments – Part 6: Rotating lasers

Serving as the fourth edition, this document prescribes user-friendly field procedures for verifying the precision and performance of rotating laser instruments in surveying, building, and construction. Designed primarily for in-situ use, the procedures enable organizations to rapidly evaluate both short-term repeatability and longer-term reproducibility (between-day precision) of laser-based leveling and alignment equipment.

ISO 17123-6:2025 delineates two field test approaches—a simplified and a full procedure—allowing users to tailor verification activities to the technical and operational demands of specific projects. In addition to statistical evaluation methods for uncertainty quantification, the standard draws attention to sources of error (meteorological, equipment setup, and test geometry) and guides operators on establishing uncertainty budgets following ISO/IEC Guide 98-3 (GUM). The flexibility and practicality of these procedures—requiring no special ancillary equipment—make the standard indispensable for construction site quality assurance.

Key highlights:

• Practical and adaptable field test procedures for rotating laser instruments
• Systematic guidance for evaluating uncertainty under real-world conditions
• Supports adherence to best practices in construction and geodetic measurement

Access the full standard:View ISO 17123-6:2025 on iTeh Standards

ISO 3966:2025 - Fluid Flow in Closed Conduits: Pitot Static Tubes

Measurement of fluid flow in closed conduits – Velocity area method using Pitot static tubes

The fourth edition of ISO 3966 supplies a foundational methodology for calculating volumetric flow rates in closed conduit systems, such as water supply pipelines or process engineering loops. The document covers the complete lifecycle of flow measurement—from the design specification and selection of dual-ported Pitot tubes, through installation, to the calculation of local velocities derived from measured pressure differences.

ISO 3966:2025 comprehensively addresses technical parameters such as flow regime, fluid properties, measurement uncertainty, point selection, corrections for turbulence and stem blockage, error analysis, and the graphical/numerical integration of velocity profiles. New in this edition are harmonized calculation models, expanded uncertainty evaluation guidance, and updated annexes offering worked calculation examples and clarification on advanced corrections. This standard is intended for engineers, plant operators, and calibration laboratories needing confident, traceable flow measurement in closed circuits.

Key highlights:

• Authoritative guidance for velocity area flow measurement with Pitot tubes
• Enhanced uncertainty evaluation and correction requirements
• Alignment with the latest practices in process industries and utility management

Access the full standard:View ISO 3966:2025 on iTeh Standards

Common Themes and Industry Trends

Several cross-cutting themes appeared within the July 2025 standards portfolio:

• Emphasis on Uncertainty and Traceability: Both geodetic field procedures and laboratory methods for radioactivity and fluid flow place renewed focus on quantifiable measurement uncertainty, in line with evolving customer and regulatory requirements for traceable, reliable data.
• Field-Ready Verification Guidance: The new and revised ISO 17123 standards reinforce a broad industry move toward pragmatic, user-friendly field measurement protocols, reducing downtime and increasing instrument deployment confidence in construction, infrastructure, and surveying.
• Alignment with Technological Advances: The coverage for multi-mode ultrasonic devices, modern GNSS systems, and high-frequency surgical instrumentation reflects the sector’s responsiveness to rapidly evolving technology and the need to bring standards up to date for next-generation equipment.
• Greater Support for Regulatory Compliance: Enhanced calibration, reporting, and uncertainty documentation supports organizations in regulatory interactions, particularly where laboratory accreditation, health, safety, or performance claims are in scope.

Industries receiving the most attention included geodesy and surveying, medical device manufacturing, environmental monitoring, and fluid dynamics/process engineering—underscoring the centrality of accurate measurement in risk management and process optimization across sectors.

Compliance and Implementation Considerations

For Organizations and Practitioners:

1. Prioritize Standard Adoption: Integrate the procedures and requirements from these new standards into company quality management and field verification programs as soon as possible, especially where regulatory or contract compliance is at stake.
2. Train Field and Laboratory Personnel: Ensure relevant personnel are fully competent in applying the new test and uncertainty procedures—particularly the multistage GNSS verification process and advanced uncertainty calculations for Pitot tube flow measurement and radioactivity assays.
3. Update Internal Protocols: Revise company SOPs and instrument maintenance documentation to mirror the technical specifics and evaluation methods introduced in the 2025 standards, ensuring alignment with ISO and IEC expectations.
4. Monitor Regulatory Developments: Recognize that implementation of revised standards can signal shifts in regulatory requirements. Engage with accreditation bodies and regulatory agencies to ensure all measurement and reporting practices fully align.

Timeline for Compliance:

• For most organizations, a 6-12 month transition period after publication is customary for integrating new procedures, though sector-specific requirements (e.g., for medical devices or environmental labs) may dictate shorter or more stringent timelines.
• Early adoption is advisable where high-accuracy, risk-based, or customer-critical measurement outcomes are involved.

Helpful Resources:

• Full-text standards via iTeh Standards
• ISO/IEC uncertainty guidance (ISO/IEC Guide 98-3, ISO 11929)
• Webinars and training from national standards bodies and instrument manufacturers

Conclusion: Key Takeaways from July 2025

The standards published in July 2025 represented a significant step forward for practitioners in metrology and measurement. Updates to the ISO 17123 series addressed the pressing needs of field verification for both GNSS and rotating laser systems. ISO 19361 and ISO 3966 brought laboratory and process measurement into closer alignment with modern best practices and uncertainty management. EN IEC 61847 modernized the approach to ultrasonic medical instrumentation, capturing recent advances and regulatory imperatives.

Professionals and organizations engaged in surveying, process engineering, laboratory analysis, and medical device design are strongly encouraged to:

• Systematically review the 2025 editions to identify new requirements and recommended practices relevant to their operations
• Adjust verification, calibration, and reporting methodologies to ensure sustained compliance and measurement confidence
• Engage with training and technical resources to ensure seamless adoption

Ultimately, staying current with these publications secures technical credibility, facilitates regulatory approval and customer trust, and positions organizations at the leading edge of quality and precision. For detailed requirements and the complete texts, consult each linked standard on the iTeh Standards platform and consider subscribing for ongoing updates.