Between 05 -06, May 2022 BTIC technical team accompanied with the German expert had conducted the field monitoring at M's pig located in Prey Nob district, Preah Sihanoukville. The purpose of this mission aimed to inspect and monitor the new desulfurizing Systems as well as genset performance. After measuring the gas quality, the H2S concentration after desulfurizing units was still high after 24/7 full operation within 3 weeks after changing the new pellets so its efficiency was least effective. With regard of this issue, BTIC technical team recommended operators to change new pellets.