ISO 9934-2:2015

Overview

ISO 9934-2:2015 - Non-destructive testing - Magnetic particle testing - Part 2: Detection media specifies the significant properties and test methods for magnetic particle detection media used in magnetic particle testing (MPT). It covers products such as magnetic inks, dry powders, carrier liquids, and contrast-aid paints, and defines how suppliers and users must verify performance, stability and safety of these materials.

Key topics and requirements

• Scope and classification: Defines classes of detection media (magnetic inks, powders, concentrates, ready-for-use products) and the expectation that inks form a uniform suspension when agitated.
• Safety precautions: Notes that materials may be harmful, flammable or volatile and mandates compliance with relevant health, safety and environmental regulations.
• Testing types:
  • Type testing - demonstrate suitability for intended use.
  • Batch testing - demonstrate conformity of a manufactured batch to the approved type.
  • In-service testing - verify continued performance during use.
• Performance tests and reference blocks: Performance, type and in-service tests are carried out using procedures in Annex A and reference blocks described in Annex B.
• Particle size: Defines particle-size reporting (lower diameter dl, average da, upper diameter du) with percentile rules (≤10% below dl, 50% above/below da, ≤10% above du). For dry powders dl is generally ≥40 µm. Methods such as Coulter or equivalent can be used for inks.
• Fluorescence: Specifies measurement of the fluorescent coefficient (β) and stability tests for fluorescent powders and inks under defined UV-A illumination and luminance measurement conditions.
• Temperature resistance: Requires no degradation after heating for 5 minutes at the supplier-specified maximum temperature, verified by repeat performance testing.
• Other test parameters: Colour consistency, carrier-liquid viscosity, flash point, corrosion (steel and copper tests), mechanical stability (short-term and endurance tests), foaming, pH, storage stability, solids content, sulfur/halogen content.
• Documentation and labelling: Suppliers must provide test certificates reporting results and tolerances; packaging and labelling requirements are specified.

Practical applications and users

ISO 9934-2 is essential for:

• NDT laboratories and inspectors performing magnetic particle testing to ensure reliable defect detection.
• Manufacturers and suppliers of magnetic inks, powders and carrier liquids to certify product conformity and produce test certificates.
• Quality managers and procurement in industries using MPT (aerospace, automotive, oil & gas, rail, heavy industry) to select compliant detection media.
• Certification bodies and auditors verifying supplier claims and batch conformity.

Using ISO 9934-2 helps maintain consistent detection sensitivity, safety, and traceability of MPT detection media across supply chains.

Related standards

• ISO 9934-1 (General principle)
• ISO 9934-3 (Equipment)
• Referenced test standards (e.g., ISO 2160, ISO 3104) for complementary test methods.