BS ISO 20676:2018 pdf free.Natural gas一Upstream area一Determination of hydrogen sulfide content by laser absorption spectroscopy. Sampling shall be performed in accordance with ISO 10715. All the materials used for sampling equipment and transfer lines shall be inert to sulfur compounds. For direct sampling, it should include sample conditioning to ensure the gas injected into the analysis unit does not contain any liquid water, dust or liquid hydrocarbons. WARNING — HS is poisonous, it is important for the user to establish appropriate safety and health practices. 7.4 Measurement of hydrogen sulfide in natural gas sample Suitable instrument should be selected according to the content of hydrogen sulfide and accuracy requirement. The analyser should be in the measurement mode while doing the measurement. Connect the gas sample with the analyser according to Figure 2. Adjust the input pressure to 0,2 MPa to 0,4 MPa by the gas regulator. Keep a constant and stable flow rate. The change of the flow rate should be less than 10 %. Sweep the analyser with the gas flow for at least 2 mm. After the sulfur-containing sample is tested, it should go through the absorption solution before it is vented. 7.5 Data processing When the analyser…