For the validation of processes in an AER contaminated test tubes (per ISO/TS 15883-5 Annex I) are used as analogues to endoscope channels. The cleaning performance is checked by residual protein detection with the modified OPA method.

The performance of the overall process is examined microbiologically, using a test soil to which E. faecium has been added.

At the end of the process step being tested, the test tubes are removed from the AER, visually inspected for cleanliness and returned to SMP for further evaluation.