Methods : ASTM D7621, IP 570, ISO/PAS 23263, ISO 8217 A compact, bench-top instrument designed to accurately measure total hydrogen sulphide (H?S) content in fuel oils, distillates, and petroleum blend stocks (0–250 mg/kg). Integrated with a Vapour Phase Processor (VPP) to eliminate interfering components for precise results, it offers automated sample mass calculation, real-time test visualization, and gas calibration. Fully compliant with IP 570 and ISO 8217 requirements, this analyser ensures reliable H?S detection and quality control.