What provision should be made when using rigid PVC for sewage systems?

When using rigid PVC for sewage systems, providing flexible hose connections is essential because it allows for the necessary movement and vibration that can occur in marine environments. Vessels experience various stresses and shifts while in motion, and rigid materials can crack or break under these conditions if not appropriately accommodated. Flexible hose connections serve as a buffer, absorbing movement and preventing damage to the sewage system.

This flexibility also assists in installation, enabling easier adjustments and alignments between different sections of the piping. Given the nature of sewage systems, which can involve varying pressure and potential blockages, incorporating flexible hose connections can enhance reliability and reduce maintenance issues over time.

While the other choices might relate to general plumbing considerations, they do not address the specific requirements for ensuring durability and functionality of sewage systems using rigid PVC.