Although the handling of surgical wounds or burns determines the risk of infection, the presence of such a problem does not prove that there was a breach in sterile technique. There is no such thing as complete sterility in open air, and the hospital bed is a "dirty" environment. Nonetheless, there is a basic method for changing a "sterile" dressing to minimize the risk of wound infection. In the process of removing the old dressing and then opening the new gauze pads and other materials and applying them, the wound and the dressing materials must not touch bare hands or any non sterile item in the patient's surroundings. Thus persons providing wound care first spread out a sterile sheet of absorbent paper with plastic backing. Then they open the dressing pack and dump it onto the sterile field without touching the contents. Following that, they don a pair of sterile latex or vinyl gloves, treat, and dress the wound. The important principle in this procedure is to identify sterile versus non sterile and keep the two worlds separated.