In which mode is CHT management not typically necessary?

The correct answer is the mode during maintenance because, in this scenario, the ship is typically not underway, and the focus is on equipment and system repairs rather than maintaining operational conditions. During maintenance, the ship's systems, including the collection, holding, and transfer (CHT) management, can be isolated or serviced, and the procedures for handling waste can be more controlled and confined.

In port, at sea, and while transiting, CHT management is crucial due to the proximity to populated areas or the need to conform to environmental regulations. During these modes, the ship must ensure proper waste management practices to prevent pollution and to comply with environmental laws and naval regulations, which make the handling of waste a high priority. Thus, CHT management takes a backseat only during the maintenance phase when operations are temporarily halted, allowing for greater flexibility in waste processing and management.