According to the Levine Quantitative Swab Technique, the wound should be rinsed with sterile saline and patted dry with sterile gauze. No eschar, devitalized tissue, dried exudate, or necrotic tissue should be part of the sample. The area should be debrided (with saline and gauze) but do not use antiseptic such as hydrogen peroxide, which may give a false negative result. The healthiest part of the wound should be targeted. Press the swab with just enough pressure to express and collect fluid, but try to avoid causing pain. Some argue for making a zig-zag pattern. A minimum of 1 square centimeter should be sampled. Others suggest swabbing from margin to margin (not periwound area). The swab should only touch the wound to be sampled and nothing else.