How did the Titanic’s watertight bulkheads slow its flooding?

The Titanic was designed with 16 internal compartments separated by watertight bulkheads to manage potential hull breaches. In naval architecture, this subdivision is a critical safety measure intended to prevent a ship from sinking by containing flooding to a limited area.123

The Titanic was built to a "two-compartment" standard, meaning it was engineered to remain afloat even if two of its compartments were flooded. The ship also featured doors that could be closed from the bridge to isolate these sections. By restricting the volume of water that could enter the hull at one time, these bulkheads significantly slowed the rate of flooding, allowing the ship to remain afloat for two hours and forty minutes after its collision with an iceberg.32

However, the collision damaged at least five compartments, exceeding the ship's design capacity. Furthermore, while the bulkheads were designed to contain water, they were not capped at the top, which eventually allowed water to spill over into adjacent compartments as the ship settled and listed.312