In order to evaluate some of the physical properties of the Haifa Occlusive Dressing, which is in use in our Department, temperature, moisture and the transfer of gases were measured. The Haifa Occlusive Dressing does not significantly raise the temperature of the covered burn, nor does it hinder the diffusion of gases, even when wet. Measurements taken from a patient suffering from a deep second degree burn showed that the amount of secretion over a 9-h period was 270 cm3 and the rate of secretion/unit area was 0.0125 cm/h.