[en] When a stainless steel corrodes in a neutral chloride solution with the formation of pits, the anode solution in the pits has a low pH value, is rich in chlorides and contains some H₂S, formed when the sulphide inclusions dissolve in the acid anode solution. The aim of the research work has been to study how the anode reaction is influenced firstly by the H₂S content of the anode solution and secondly by the S content and the Mo content of the steel. In the first part of the investigation an active surface of a stainless steel type 18-8 was polarized in acid chloride solutions with different pH values and different H₂S contents up to 100 ppm at increasing potentials. The result was that hydrogen ions and H₂S widened the active region in the polarization curve in all directions. In the second part of the investigation active surfaces of austenitic steels with different S and Mo contents were polarized in an acid chloride solution at increasing potentials. The result was that S in the steel widened and Mo contracted the active region in the polarization curve in all directions. Applied to pits, developing under conditions in practice, the results indicate that sulphur increases and molybdenum reduces the potential difference in the corrosion cell but the effect is not very great and the corrosion rate is changed only moderately. The essential influence of the two components is supposed to be that sulphur will counteract and molybdenum will facilitate the passivation of the active surface in a pit. This will influence both the moment when a pit will start to grow and the moment when it will stop. Thus on average the life of a pit in a steel will be extended with increasing sulphur content and shortened with increasing molybdenum content. (author)