ISO 5576:1997

Overview

ISO 5576:1997 - Non-destructive testing - Industrial X‑ray and gamma‑ray radiology - Vocabulary - is an ISO vocabulary standard (first edition, 1997) that defines and harmonizes terminology used in industrial radiographic NDT (X‑ray and gamma‑ray). Prepared by ISO/TC 135 (Nondestructive testing), SC 5 (Radiation methods) in collaboration with CEN/TC 138, the document provides clear definitions in English and French with equivalent German terms published under the responsibility of DIN. Only the English and French entries are the official ISO terms.

Key topics

The standard establishes consistent meanings for fundamental radiology and radiography concepts, including:

• Radiation and interaction terms: absorption, attenuation, attenuation coefficient, Compton scatter, backscatter/back‑scattered radiation, build‑up factor.
• Equipment and components: anode, cathode, betatron, collimator, cassette, blocking medium, constant potential circuit.
• Image and film concepts: ageing fog, artefact (false indication), characteristic (sensitometric) curve, calibrated density step wedge, clearing time, continuous spectrum.
• Measurement and image quality: beam angle, contrast (image/object/radiation/visual), contrast sensitivity (thickness sensitivity), average gradient.
• Techniques: computerized tomography (CT) defined as axial CT computed from X‑ray absorption measurements.

Because ISO 5576 is a vocabulary standard, its primary “requirement” is to provide authoritative, unambiguous definitions and multilingual equivalents so technical documents, specifications and communications use the same terms consistently.

Applications

ISO 5576 is used to:

• Standardize terminology in NDT procedures, reports and specifications for industrial X‑ray and gamma‑ray radiology.
• Improve clarity in procurement, regulatory documentation, training materials and international collaboration.
• Support quality assurance, inspection protocols, and interpretation of radiographs by ensuring professionals share common definitions.
• Serve as a reference for calibration, testing method descriptions, and harmonization between national standards bodies (ISO/CEN/DIN).

Who uses this standard

• NDT/radiography technicians and supervisors
• Inspection and quality‑assurance engineers
• Standards writers, test laboratories and certification bodies
• Equipment manufacturers and service providers
• Educators and trainers in industrial radiographic methods
• Regulators and safety officers dealing with radiological inspection

Related standards

• Prepared by ISO/TC 135 (Nondestructive testing), Subcommittee SC 5 (Radiation methods)
• Collaborative work with CEN/TC 138 (Nondestructive testing) and national bodies (e.g., DIN)

Keywords: ISO 5576:1997, non‑destructive testing, industrial X‑ray, gamma‑ray radiology, vocabulary, radiography terminology, attenuation coefficient, Compton scatter, contrast sensitivity.