A utensil that was used for non-kosher food, or for milk and meat, generally requires Hag'ala – immersion in hot water. The question arises concerning a situation where one dish requires Hag'ala, but it becomes mixed with the rest of the set and cannot be discerned. Must one perform Hag'ala on the entire set of dishes before using any dish, given the possibility that the one he uses is the one that became non-kosher?
Both the Ben Ish Chai (Rabbi Yosef Chayim of Baghdad, 1833-1909) and Chacham Ovadia Yosef ruled that in such a case the non-kosher dish is "Batel Be'rov" – negated by the majority. Since the dish constitutes but a minority among a majority of useable dishes, one may use any dish from the set without concern, and he need not perform Hag'ala on any of the dishes. Chacham Ovadia advises, however, that one first refrain from using any of the dishes for a period of twenty-four hours. At this point, any forbidden taste in the walls of the dish becomes "Pagum" (spoiled), which is forbidden only by force of Rabbinic enactment (as opposed to Torah law), regarding which there is greater room for leniency.
This ruling applies to all kinds of dishes – metal, porcelain, chinaware, and so on.
Thus, if a non-kosher dish becomes mixed with and indiscernible from kosher dishes, one should not use them for a period of twenty-four hours, after which he may use any of the dishes, even without performing Hag'ala.
