PT – Penetrant Testing

Penetrant Testing (PT)

Penetrant testing (PT) is one of the oldest and most proven methods for detecting surface-breaking defects — and it remains one of the most reliable. The method works on virtually all non-porous materials, including stainless steel, aluminium and other non-magnetic metals where magnetic particle testing cannot be used. Nordic NDT performs penetrant testing with personnel certified to EN ISO 9712, within the scope of our SWEDAC-accredited laboratory (ISO/IEC 17025).

How does it work?

A colored or fluorescent liquid is applied to the surface and penetrates into any surface-breaking defects through capillary action. After a controlled dwell time, excess penetrant is removed and a developer is applied — drawing the penetrant back out of the defects and making them clearly visible as colored or fluorescent indications. The method follows EN ISO 3452.

Where is it used?

• Stainless & non-magnetic materials — Crack detection in stainless steel, aluminium, titanium and copper alloys where MT is not applicable.
• Pharmaceutical & chemical industry — Inspection of stainless process equipment, piping and vessels in clean environments.
• Weld inspection — Surface defect detection in welds across all material types.
• Manufacturing & maintenance — Quality control of machined components, castings and safety-critical parts.

Why choose Nordic NDT?

PT is a method where discipline in every step — cleaning, dwell time, development, assessment — determines the reliability of the result. Our certified technicians follow strict procedures under our SWEDAC accreditation, and every result is delivered with full documentation and traceability.

Contact us

Need penetrant testing — on site or in our laboratory? Get in touch.

+46 8 715 16 60