Regional Basic Professional Training Course in Korea

Regional Basic Professional Training Course (BPTC) on Nuclear Safety
the examinations.
A visual examination is used to provide information on the general condition of the part,
component or surface to be examined, including such conditions as scratches, wear,
cracks, corrosion or erosion on the surface; or evidence of leaking. Optical aids such as
television cameras, binoculars and mirrors may be used. Surface replication as a visual
examination method may be considered acceptable, provided that the surface resolution is
at least equivalent to that obtainable by the visual observation. Visual examination
requiring a clean surface, or decontamination for proper interpretation of results, should
be preceded by appropriate cleaning processes.
A surface examination is undertaken to delineate or verify the presence of surface or near
surface flaws. It may be conducted by a magnetic particle, liquid penetrant, eddy current,
or electrical contact method.
A volumetric examination is undertaken for the purpose of indicating the presence, depth
or size of a sub‐surface flaw or discontinuity, and usually involves radiographic or
ultrasonic techniques. Radiographic techniques, employing penetrating radiation such as
X rays, gamma rays or thermal neutrons, may be utilized with appropriate image
recording devices, not only to detect the presence of flaws, but also to establish the size
of the flaw. An appropriate ultrasonic testing method is the most common method used to
establish both the length and depth of flaws.
Alternative examination methods, a combination of methods, or newly developed
techniques may be substituted, provide that the results yield demonstrated equivalence or
superiority, and if results from both methods are comparable.
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