What is the purpose of a watertight door?

The purpose of a watertight door is fundamentally to prevent the spread of water in the event of flooding. These doors are specially designed to seal off compartments on a ship or in a building to contain water and minimize damage from flooding incidents. When a watertight door is closed, it creates a barrier that limits the flow of water from one area to another, thereby ensuring that any flooding that does occur does not compromise the integrity of the entire structure. This capability is crucial for maintaining buoyancy and stability in marine environments and for protecting vital systems and equipment from water damage, enhancing overall safety and operational readiness.

While watertight doors can serve various functions in a maritime or building context, their primary role remains focused on water containment. Other functions, such as restricting access to certain areas or enhancing air quality, are not their main intent and do not align with watertight integrity requirements.