An apparatus for obtaining containers from a sheet material includes an operating unit for processing the sheet material. The operating unit includes an upper operating part for interacting with an upper surface of the sheet material and a lower operating part for interacting with a lower surface of the sheet material. The apparatus further includes a sterilizing arrangement for sterilizing a space adjacent to the upper operating part and to the lower operating part, so as to create a substantially aseptic environment above and below the sheet material.