The evaluation of film processing using the STEP test (sensitometric test for the evaluation of processing) is based on the identification of significant deviations in the processor-chemicals-film system. Ideal processing conditions are established for this type of evaluation. A standard film is processed according to the manufacturer's recommendations, i.e. standard processing at 100. The film is exposed to the light of a calibrated sensitometer and the sensitometric steps are read with the use of a densitometer. A standard curve (OD × STEP) is therefore obtained. The percentual deviation should be lower than 20% compared to the standard curve. This method is useful to identify processing problems. We tested processors from several public/university hospitals and found that approximately 33% of the equipments had inadequate processing conditions.
Automatic processors; Radiographic films; Sensitometry; STEP test
