PDT is based on real-time diagnostics of physics process which goes in material and structure of facilities
The result of interaction of energy and material are various physical processes taking place in the material: stress concentration, deformation, corrosion, fatigue damage, destructions.
Phonon emission appears on areas of defects formation and growth, said another way of hazardous operating conditions
PDT inspection consists in acquisition, recording, processing, analyzing and interpreting characteristic and factors of phonon emission propagation.