The commissioning test of BWTS were carried out to validate that correct operation of system, mechanical, physical, chemical and biological processes are working properly. InoShip LT UAB experts boarded the vessel to take and test the ballast water samples. The system has been installed on board fore more than one year. The managers were struggling to achieve the final commissioning and the due date for testing set by the RO has been coming to the limit. The testing team has boarded the vessel and performed the sampling and testing. Flag requirements were addressed properly by additional sampling and testing. The technical report documenting the achieved results was issued and handed over to shipowners representative upon receipt of all incoming information, few days after return to office. The report has been finally submitted by ship manager to RO (BV) and subsequently approved.