Is there any recognized industry standard regarding returning media to use after it has been swept up from the floor area around a peening cabinet? I have observed this practice at two locations and was informed that the shot is run through a classifier and then reused. I cannot find specific language on this practice in the pertinent SAE/AMS specifications, but it seems to me that it would at least violate the spirit of the "clean and free of foreign materials" wording of AMS 2431. Of great interest would be any documented instances where such a practice has resulted in unacceptable results. My thanks to anyone who can offer clues or guidance on the potential for serious consequences.