Hydrogen sulphide Most of the hydrogen sulphide (H2S) present in the atmosphere originates naturally from the decomposition of organic matter. Anthropogenically, it occurs in processes in which sulphur compounds and organic matter are involved at high temperatures. H2S is highly toxic to humans and other living organisms, even at low concentrations and affects mainly to the respiratory system with the first symptoms being nose, throat and eyes irritation. This compound begins to be detected by the human sense of smell at concentrations much lower than those that can have harmful effects on health. Some industrial activities that emit this gas include paper pulp manufacturing, oil refining, water treatment plants and the viscose manufacturing textile industry. Short-term exposures of high concentrations can cause headache, dizziness and vomiting. H2S cartridge The H2S cartridge has a built-in electrochemical sensor very sensitive to its target pollutant allowing to detect small changes in H2S concentration. This cartridge also responds to methyl mercaptan (CH4S) and other total reduced sulphur compounds (TRS). To cover different applications, there are 2 measurement ranges: • Type A: detects low ppb concentrations in real environments. Although the Kunak algorithm corrects the temperature variations well, it is not recommended to use this cartridge to measure levels below 15 ppb. • Type B: a higher range version that can measure up to 20 ppm, not so precise at low concentrations. Unit of measurement Measurement range (1) Resolution (2) Limit of Detection (LOD) (7) Repeatability (8) Response time (9) Operating temp. range (3) Typical slope Recommended RH range Operating life (5) Guarantee range Typical Intra-model variability