Piazza, Bruno
Bruno Piazza was an Italian Jew deported to Auschwitz at the end of July 1944. In a 1956 brochure, he claimed that he experienced a homicidal gassing at Auschwitz carried out inside a barracks that had 20 showers on the ceiling. Then some clerk wearing a mask entered the building, sprinkled potassium-cyanide powder onto the floor, turned on the shower, left, closed the door, and after ten minutes we were all dead, asphyxiated.
But as a dead man walking, or perhaps as a zombie, he managed to come home to Italy and write this brochure to tell us that this powder-shower system had replaced the previous method of ejecting cyanide-gas cylinders into the chamber. This was allegedly unsafe because sometimes the cylinders didn’t break on impact, requiring the procedure to be repeated four or five times. None of this nonsense has ever been taken seriously by anyone. (For more details, see Mattogno 2021, pp. 348f.)