Penetrant Sensitivity Levels

Penetrant materials used in penetrant testing are classified according to their ability to detect very small surface defects. These sensitivity levels are commonly defined as Level ½, Level 1, Level 2, Level 3, and Level 4.

As the sensitivity level increases, the penetrant becomes capable of detecting smaller and more subtle surface cracks or discontinuities. Higher sensitivity penetrants are typically used in critical inspection applications.

Level ½ – Ultra Low Sensitivity

Level ½ penetrants are used for low sensitivity applications where only relatively large surface defects need to be detected.

Level 1 – Low Sensitivity

Level 1 penetrants are suitable for general industrial applications and can detect moderate surface discontinuities.

Level 2 – Medium Sensitivity

Medium sensitivity penetrants are commonly used in manufacturing inspections and routine quality control processes.

Level 3 – High Sensitivity

Level 3 penetrants are designed for high-sensitivity inspections and are capable of detecting smaller surface cracks. They are often used for critical components.

Level 4 – Ultra High Sensitivity

Level 4 penetrants provide extremely high sensitivity and are used for detecting very fine surface defects. They are typically applied in industries with strict safety requirements such as aerospace and defense.

Penetrant sensitivity levels are generally defined according to international standards such as AMS 2644 and ASTM E1417.

NEXSEN provides engineering solutions and penetrant inspection systems designed to support industrial quality control processes across various sensitivity levels.

Penetrant Classification

Type 1 – Fluorescent

Type 2 – Visible

Method A – Water Washable

Method B – Post Emulsifiable Lipophilic

Method C – Solvent Removable

Method D – Post Emulsifiable Hydrophilic

Sensitivity Levels

½ / 1 / 2 / 3 / 4