Subsequently, a detailed inspection on the Main Sheave was carried out, and all Main Sheaves within which a crack was detected were replaced. Ship Management Company A lifted the ban on the condition that a thorough check of the Main Sheave be carried out prior to the start of cargo handling operation. In addition, Ship Management Company A and the Crane Manufacturer investigated the cause of the accident, and manufactured an improved type of Main Sheave. Improvements included the change of rim material to S355J+M, which features enhanced ductility, and the re-engineering of production procedures. All 90 Main Sheaves onboard the Vessel A and its eight sister ships were replaced with the improved sheaves under the supervision of inspectors from the Crane Manufacturer and GL (2) Guideline Document Ship Management Company A prepared a guideline document, intended for use on Vessel A. that lists usage instructions and maintenancelinspection procedures and also requires the visual inspection of sheaves and reporting every six months. Ship Management Company A distributed this document to all of its ships as a means of stricter guidance 6.1.2 Actions Taken by Vessel A Under the guidance of Ship Management Company As the crew of Vessel A ensured thorough undergoing of inspections prior to the start of cargo handling operations and maintenance/service procedures pursuant t PMS 6,2 Actions Taken by the Crane Manufacturer According to the written reply to the questionnaire from the Crane Manufacture, the Sheave Manufacture carried out the following measures and the Crane Manufacture accepted the measures. (1) Additional material test for the angle profiles used for the cold forming of rims and if found necessary, another test prior to the cold forming (2) A hand grinding process of the inside of the rim in the area between the web plates has been added to remove possible small crack like overlapping and rolled in scales 6.3 Actions Taken by the Contract Company and Company C According to the interviews and the written reply to the questionnaire from the person in charge of the Contract Company, the Contract Company accepted job safety instructions from the Labor Standards Inspection Office on December 5, 2008. In response to this the Contract