Which part of the water tight door is crucial for its sealing capability?

The sealing capability of a watertight door fundamentally relies on the gasket. A gasket is designed to form a tight seal between the door and its frame, preventing water from passing through. When the door is closed, the gasket compresses, filling any gaps and ensuring that no water can leak into the surrounding area. This is essential in environments where water pressure can be significant, such as on ships or in flood-prone facilities.

While the frame, lock, and handle are important for the overall functionality and security of the door, they do not directly contribute to the watertight sealing. The frame provides structural support, the lock secures the door in place, and the handle allows for operation, but it is the gasket that is specifically engineered to provide the necessary barrier against water ingress.