Thanks for the replies everyone,
I have done some more research, contacted a process authority, and spoke with our USDA inspector as well to see what he prefers to see in the situation when non-ABF is ran before ABF. This is what I have found...
1.Antibiotic free is a labeling issue, therefore there needs to be a complete break between ABF and Non-ABF (which we already know).
2.There is no scientific means to prove that a flock is raised antibiotic free, therefore proof (from the standpoint of the USDA) is given through required documentation.
3. Since all meat is tested to be free from antibiotic residue before slaughter, all meat would be "antibiotic free" except for the fact that USDA has a definition of "antibiotic free" as animals raised without the use of antibiotics.
4. So to comply with the labeling issue we need to make sure that the equipment is "meat free" of Non-ABF meat before moving forward with ABF meat.
5. To be meat free, a water rinse would be effective, (treating it more as a species change over more so than what we would do for an allergen).
6. There needs to be a documented visual inspection before moving forward.
Thinking a little more about all of this I have to say that I feel that a water spray down is an effective means of changing over, because we could never validate (by means of testing) a full clean up procedure anyway to show that the equipment is free from residues left behind by Non-ABF meat that would affect the label claim of Antibiotic free.
I have also been told that some processors only leave a break (an empty space) on the line between ABF and Non-ABF (even when going from Non-ABF to ABF) products and do no clean up of any sort. At this point in time they may be able to do that legally because they are implementing a practice to make sure that the meat is not mixed. But from a production standpoint I think that there needs to be a little more, such as the water rinse, to ensure the break between non-ABF and ABF. As time goes on and the more that ABF products are produced, I am sure that the government will take more of a stand and establish some validation guidelines as they have with the gluten free label claims. But until then we are responsible for our own policies and practices.