acceptable quality level
the maximum percent defective or the maximum number of units defective per hundred units that, for the purpose of sampling test, can be considered satisfactory as a process average.

amorphous silicon (a-Si) X-ray detector, n
an amorphous silicon (a-Si) X-ray detector consists of a glass substrate with a matrix of photodiodes fabricated from amorphous silicon and switches arranged in rows and columns upon it; the photodiodes are activated by light photons emitted from a scintillator which is activated by X rays and is usually in close contact with the diode matrix.

calibration, instrument, n
the comparison of an instrument with, or the adjustment of an instrument to, a known reference(s) often traceable to the National Institute of Standards and Technology (NIST). (See also standardiza tion, instrument.)

defect, n
one or more flaws whose aggregate size, shape, orientation, location, or properties do not meet specified acceptance criteria and are rejectable.

discontinuity, n
a lack of continuity or cohesion; an intentional or unintentional interruption in the physical structure or configuration of a material or component.

evaluation, n
a review, following interpretation of the indica tions noted, to determine whether they meet specified acceptance criteria. examination, n a procedure for determining a property (or propertics) or other conditions or characteristics of a material or component by direct or indirect means.

false indication, n
an NDT indication that is interpreted to be caused by a condition other than a discontinuity or imper fection. flaw, n—an imperfection or discontinuity that may be detectable by nondestructive testing and is not necessarily reject able.

flaw characterization, n
the process of quantifying the size, shape, oricntation, location, growth, or other propertics, of a flaw based on NDT response.

imperfection, n
a departure of a quality characteristic from its intended condition. indication—the response or evidence from a nondestructive examination. Discussion—An indication is determined by interpretation to be relevant, non-relevant, or false.

inspection, n
a procedure for viewing or observing visual characteristics of a material or component in a careful, critical manner.

interpretation
thc detcrmination of whether indications arc relevant or nonrelevant.

interpretation, n—the determination of whether indications are relevant, nonrelevant, or false. Nondestructive Evaluation—see Nondestructive Testing. Nondestructive Examination—see Nondestructive Testing. Nondestructive Inspection—see Nondestructive Testing.

Nondestructive Testing (NDT), n
the development and application of technical methods to examine materials or components in ways that do not impair future usefulness and serviceability in order to detect, locate, measure and evaluate flaws; to assess integrity, properties and composition; and to measure geometrical characteristics.

nonrelevant indication, n
an NDT indication that is caused by a condition or type of discontinuity that is not rejectable. False indications are non-relevant.

relevant indication,
an NDT indication that is caused by a condition or type of discontinuity that requires evaluation.

standardization, instrument, n
the adjustment of an NDT instrument using an appropriate reference standard, to obtain or establish a known and reproducible response. (This is usually done prior to an examination, but can be carried out anytime there is concern about the examination or instru ment response. (See also calibration, instrument.)

test, n
a procedure for determining a property or character istic of a material or a component by direct measurement.