Overview
EN ISO 19232-5:2018 (CEN) is part of the ISO 19232 series on image quality in non-destructive testing (NDT). This standard specifies a method to determine the total image unsharpness and basic spatial resolution of radiographs and radioscopic (digital) images using duplex wire-type image quality indicators (IQI). It is applicable to film and digital detectors and defines limits for effective use of duplex IQIs with different tube voltages.
Key topics and requirements
- Scope and limits
- IQIs with up to 13 wire pairs are effective with tube voltages up to 600 kV.
- IQIs with more than 13 wire pairs are intended for tube voltages below 225 kV.
- Use at megavolt source voltages may produce unsatisfactory results.
- Definitions and metrics
- Total image unsharpness (UT), basic spatial resolution (SRb), and line pairs/mm (lp/mm) are defined consistently for film and digital detectors.
- Detector vs image values are distinguished (e.g., detector SRb vs image SRb) and related to magnification and effective pixel size.
- Measurement methods
- Visual evaluation on film or monitor.
- Digital evaluation using a profile function and a 20% modulation depth criterion.
- Interpolated values derived from linearized profile functions when finer resolution is needed.
- IQI specification
- Physical and marking requirements for duplex wire IQIs (material, dimensions, holder) and declaration of conformity.
- Documentation and performance
- Requirements for reporting results, and information on precision and bias.
- Evaluation classes
- Image quality classes and application guidance for various inspection scenarios are provided.
Practical applications and users
- Intended for professionals performing NDT radiography and radioscopy, including:
- NDT radiographers and inspectors
- Quality assurance/quality control managers in manufacturing, aerospace, power generation, and oil & gas
- Suppliers and manufacturers of digital detectors and imaging plates
- Personnel responsible for procedure qualification and acceptance testing
- Typical uses:
- Verifying detector performance and image sharpness
- Routine image quality checks in inspection workflows
- Comparing film vs digital imaging performance and setting acceptance criteria
Related standards
- ISO 19232 series (other parts cover different IQIs and image quality assessments)
- ISO 5576 - NDT vocabulary for radiology
- ISO/IEC 17050-1 - Supplier’s declaration of conformity
Keywords: EN ISO 19232-5:2018, non-destructive testing, image quality, radiographs, duplex wire-type IQI, image unsharpness, basic spatial resolution, radioscopic images.
