Processing Cycle and the STEP Test
The proliferation of cycle times used in mammography has made the distinction between standard processing and extended processing confusing. This has resulted in uncertainty in recording the type of processing cycle for some systems.
Currently, the "standard" processing cycle which refers to a nominal cycle time of 90 seconds can have a range of 88s – 150s (which corresponds to 24s – ~35s development time), depending on the developer temperature. Likewise, the "extended" processing cycle can have a nominal cycle time in the range 170s – ~240s (43s – ~55s development time).
Furthermore, although the STEP test is an evaluation of the processing conditions regardless of the type of film used by the facility, the fact that some mammography films are designed to gain most of their speed increase at about 32s development time compared to their gain at a fully extended cycle (~55s development time) has created a tendency in such situations to refer to this as extended processing and record it as such in conjunction with the STEP test, even though this falls within the standard cycle time range.