Magnetic particle inspection (MPI) method is used to detect surface and/or near-surface flaws in ferromagnetic materials. A magnetic field is applied to the object, using a permanent magnet, electromagnet, flexible cables or hand-held prods. If the material is sound, most of the magnetic flux is concentrated below the material’s surface. If a flaw is present, thus it interacting with the magnetic field, the flux is distorted locally and ‘leaks’ in the region of the flaw. Fine magnetic particles, applied to the surface of the specimen, are attracted to the area of flux leakage, creating a visible indication of the flaw.