请修正润色In addition in terms of other file regulations the Technical Policy for Ship Water Pollution Prevention and Control classifies sewage including black water and grey water It also requires the gra

In addition, with regard to other regulations concerning file management, the "Technical Policy for Ship Water Pollution Prevention and Control" classifies sewage into two categories: black water and grey water. It also mandates the gradual implementation of control measures for grey water, such as collecting and storing sewage on board using appropriate devices and closing drainage valves in water areas where sewage discharge is prohibited, such as zones designated for protecting drinking water sources. These measures aim to prevent sewage from contaminating the surrounding water bodies. Furthermore, the policy emphasizes the importance of maintaining records for the implementation of these control measures. However, it is important to note that this document serves only as a guiding document and lacks legal enforceability.