I fielded a call on cleaning verification last week and some of the questions the person asked me included: how long has the TOSI been around in the U.S. and what does T.O.S.I stand for? I told them T.O.S.I stands for Test Object Surgical Instrument. I had to think for a moment on how old it was and then I said "wow!" has time flown by...TOSI is completing its twelfth year of being available in North America. The T.O.S.I. has been the industry standard for testing for the last twelve years. It is comprised of components of blood and there is no secret ingredient that biases the TOSI toward one cleaning method or another. The design of the TOSI reflects one of the most difficult to clean areas of a surgical instrument: the box lock area. This area, as you well know, is difficult to clean and hard for the CSSD professional to inspect. Simply put, it is a true surrogate device that represents what CSSD are doing each day: trying to clean blood off of stainless steel surgical instruments. Plenty has changed in 12 years. Cleaning verification is now coming to the forefront. It's no longer looked to as a "waste of time" or a "hindrance" but a better way to understand and to improve the cleaning process. What a paradigm shift in thinking that is from 2001. We no longer just trust that our cleaning equipment is working. We now trust but verify. Verifying with products that are backed with evidence based peer-reviewed studies. As that commercial from the 70's would say, "we have come a long way baby" on cleaning verification. We sure have, so take care and remember to "Keep it Clean".