CNOOC Limited conducted special inspections of well repair and well control safety, emphasizing downhole operation safety management It achieved all-round improvement of platform drilling/workover rig safety management through optimization of management mechanism, specifying the limits of responsibilities and liabilities, completing management system and criterion, pushing forward integrity management of drilling/workover rigs and improving management and working of professional teams. establishing and improving management system of downhole operation and well control safety, enhancing education of supervisors for rig workover, strengthening screening and rectification of well repair related to potential risks, and improving management at headquarters.