January 2026: New Non-Destructive Testing Standards for Industrial X-Ray Systems

Non-destructive testing (NDT) continues to set the benchmark for safety, precision, and efficiency within manufacturing and maintenance sectors. This January 2026, two pivotal standards—ISO 32543-2:2026 and ISO 32543-3:2026—have redefined how industrial X-ray systems are validated and monitored. These ISO publications introduce robust methodologies for measuring the effective focal spot size, a critical attribute for X-ray image clarity and diagnostic value. Industry professionals relying on accurate, repeatable results will find these updates invaluable for maintaining best-in-class performance, compliance, and traceability. This article provides a comprehensive review of both standards, offering essential guidance for anyone involved in industrial radiography, from procurement to quality assurance.

Overview / Introduction

Industrial X-ray technology is foundational to non-destructive testing—a discipline where flaw detection, dimensional verification, and internal analysis are performed without damaging the subject material. Ensuring the reliability of X-ray images primarily depends on the characteristics of the focal spot: its size, shape, and uniformity can critically affect image resolution and the detection of defects.

International standards play a vital role by creating a shared language and set of expectations for manufacturers, operators, and inspectors. They ensure that goods, components, and infrastructure meet stringent safety and quality benchmarks, not just locally but worldwide. In this article, you’ll learn about the latest ISO specifications for X-ray focal spot measurement, including their scope, technical requirements, and practical impact for the NDT community.

Detailed Standards Coverage

ISO 32543-2:2026 - Edge Method with Hole or Disk Type Test Objects

Non-destructive testing — Characteristics of focal spots in industrial X-ray systems — Part 2: Edge method with hole or disk type test objects

This standard details the edge method for measuring effective focal spot dimensions greater than 0.2 µm in X-ray systems. The procedure utilizes digital images captured from hole or disk-shaped test objects. This is particularly beneficial for scenarios in which pinhole methods (as defined in ISO 32543-1) are impractical or cannot be implemented due to setup constraints or application-specific requirements.

Scope and Application

• Applies to measurement and long-term monitoring of standard, mini, and micro focal spots in industrial X-ray tubes.
• Supports regular focal spot observation in both laboratory and field environments.
• Ideal for users who do not have access to pinhole cameras or where phase contrast needs to be avoided.

Key Requirements and Procedures

• Test Equipment: Utilizes specific test objects (typically high-precision hole or disk plates) and digital imaging systems such as computed radiography (CR) or digital detector arrays (DDA).
• Measurement Accuracy: While effective, the edge method as described here may offer less precision compared to the pinhole method (ISO 32543-1) or ISO 32543-3 for microfocus tubes, particularly if using ASTM-manufactured hole plates due to manufacturing tolerances.
• Regular Monitoring: Suitable for continual assessments, enabling organizations to track focal spot changes over the life of X-ray tubes.
• Manufacturer Use: Manufacturers may achieve improved repeatability by using test objects fabricated to tighter tolerances (per 6.2.1).

Who Needs to Comply

• X-ray equipment manufacturers, system integrators, maintenance and quality assurance personnel, and laboratories using industrial radiography.
• Particularly relevant for sectors where the precise resolution of X-ray imagery impacts safety, compliance, or product quality (e.g., aerospace, automotive, energy, infrastructure).

Practical Implications and Notable Changes

• Provides a user-friendly alternative for ongoing focal spot characterization.
• Recognizes limitations in measurement accuracy for advertising or trade—defaulting to nominal values (Annex A) for public specifications.
• Emphasizes digital workflows and supports integration with automated analysis software for profile evaluation (signal-to-noise, contrast, edge unsharpness).

Key highlights:

• Applies edge method to spot sizes >0.2 µm for digital X-ray imaging.
• Simplifies routine focal spot validation without a pinhole camera.
• Supports ongoing quality assurance and equipment monitoring.

Access the full standard:View ISO 32543-2:2026 on iTeh Standards

ISO 32543-3:2026 - Measurement of Effective Focal Spot Size of Mini and Micro Focus X-Ray Tubes

Non-destructive testing — Characteristics of focal spots in industrial X-ray systems — Part 3: Measurement of the effective focal spot size of mini and micro focus X-ray tubes

ISO 32543-3:2026 advances focal spot measurement for mini and micro focus X-ray tubes, specifically within the 5 µm to 300 µm range and up to 225 kV. This method relies on digital image evaluation following edge exposure, facilitating high-precision characterization essential for modern microfocus radiography.

Scope and Application

• Covers detailed measurement procedures for focal spots (5–300 µm) in X-ray tubes operating up to 225 kV.
• Assessment is based on edge imaging and digital profile analysis, ensuring fine granularity and repeatability.

Key Requirements and Methodology

• Test Objects & Imaging: Requires sharply fabricated edge objects for imaging using films, computed radiography, or digital detector arrays.
• Magnification and Calibration: Relies on suitable geometric magnification to enhance measurement resolution; correction for inherent unsharpness of the detector is mandatory for reliable results.
• Image Processing: Employs digital evaluation—using line profiles and calibrated pixel distances—to establish actual focal spot dimensions (length and width).
• Classification: Adopts nominal focal spot size values (from Annex A) for trade or catalog purposes, in line with industry transparency and comparability.

Who Needs to Comply

• Manufacturers and operators of microfocus X-ray equipment, inspection service providers, and R&D laboratories in industries where micron-level flaw detection is mandatory (e.g., electronics component inspection, advanced manufacturing, aerospace, and defense).

Practical Implications and Notable Changes

• Offers a precision approach to characterizing focal spots in high-resolution X-ray systems.
• Supports accurate reporting, traceability, and system benchmarking for both internal quality management and external audits.
• The standard permits its methods to be applied at higher voltages, with a note on potential accuracy trade-offs.

Key highlights:

• Enables accurate, repeatable measurement of mini/micro focal spots (5–300 µm).
• Requires digital analysis and detector unsharpness correction.
• Facilitates transparent classification and equipment specification for compliance and industry comparison.

Access the full standard:View ISO 32543-3:2026 on iTeh Standards

Industry Impact & Compliance

The January 2026 releases reshape compliance frameworks and testing strategies for many sectors using industrial X-ray imaging. By specifying clear, actionable guidelines for focal spot measurement, ISO 32543-2:2026 and ISO 32543-3:2026:

• Standardize Quality Assurance: Organizations can maintain uniform inspection practices, trace instrument drift, and reduce ambiguity in performance claims.
• Streamline Audits & Certifications: Consistent reporting and detailed classification of X-ray focal spots simplify the demonstration of system capability during supplier or regulatory audits.
• Lower Risk: Early detection of focal spot instability or drift prevents image degradation that could lead to missed defects, costly recalls, or safety incidents.

Compliance Considerations:

• Implementations should be planned carefully, especially if transitioning from older measurement methodologies.
• Staff need training on new procedures, equipment calibration, and digital evaluation techniques as outlined.
• While immediate compliance may not be mandatory for all, early adoption is recommended to remain competitive and minimize future disruption.

Benefits of Adoption:

• Improved test reliability and verifiable quality
• Enhanced reputation with customers and regulators
• Streamlined troubleshooting and maintenance of X-ray equipment

Risks of Non-Compliance:

• Compromised inspection quality
• Potential regulatory or contractual non-conformance
• Increased exposure to undetected defects and associated liabilities

Technical Insights

Common technical threads across both standards include:

• Digital Imaging Integration: Both standards emphasize the use of computed radiography and digital detector arrays. This supports increased automation, repeatability, and data traceability—the foundation for Industry 4.0 readiness.
• Profile Analysis: Measurement accuracy is enhanced through careful profile evaluation—analyzing signal-to-noise and contrast-to-noise ratios for each test setup.
• Calibration and Qualification: Calibration against known reference objects (hole or edge types) and routine validation of digital processing software are essential for reproducibility.

Implementation Best Practices

1. Assess and Update Equipment: Validate compatibility with required detector types and test objects per the standard’s recommendations.
2. Train Personnel: Ensure staff understand the requirements for accurate setup, image acquisition, and digital analysis.
3. Document and Report: Adopt the reporting templates and procedures specified to guarantee traceability and facilitate future audits.
4. Monitor Performance: Schedule regular checks to identify drift or degradation in focal spot size, addressing issues proactively before they affect measurement integrity.

Certification and Testing Considerations

• Engage with accredited labs for third-party verification where necessary.
• Ensure that new equipment procurement aligns with ISO-compliant capabilities.
• Maintain records of all calibrations, test results, and method validations.

Conclusion / Next Steps

The publication of ISO 32543-2:2026 and ISO 32543-3:2026 marks a major advancement for industrial radiographic testing. Together, they offer universal, practical, and precise approaches to focal spot measurement—addressing both routine and high-resolution requirements. Organizations relying on X-ray NDT should familiarize themselves with the latest requirements, train technical staff, and review instrumentation for compliance fit. Early adoption not only ensures ongoing quality but also demonstrates industry leadership and a commitment to safety and performance excellence.

Explore these standards and equip your organization for the next era in non-destructive testing:

• ISO 32543-2:2026
• ISO 32543-3:2026

For further updates and comprehensive access to international standards on non-destructive testing, visit iTeh Standards regularly.