Healthmark's TOSI is the first device to provide a repeatable method for evaluating the cleaning effectiveness of the automated instrument washer. This is possible because the blood soil is manufactured to exact specifications each and every time. When metered on to the stainless steel plate, the TOSI is completely analogous to a stainless steel instrument soiled with dried blood. Placed in the see-through plastic holder, the challenge is identical to the areas of instruments typically hidden from view (i.e., box locks). The routine use of this test will help ensure that your instrument washer is performing at a consistent level, enhancing the routine visual inspection of instruments.