What are the bars inside the door shell that protect passengers during a crash called?

The correct term for the bars inside the door shell that protect passengers during a crash is side impact bars. These bars are designed to absorb and distribute impact energy in the event of a side collision, enhancing the overall safety of the vehicle occupants. Side impact bars are typically made from high-strength materials and are strategically placed within the door structure to minimize the risk of injury to passengers by reinforcing the area around the door and providing an additional layer of protection.

While other terms like reinforcement bars, crash beams, and door beams may refer to components that provide structural integrity or impact resistance in various automotive contexts, side impact bars specifically denote those features designed to mitigate the effects of side impacts, making them essential in modern vehicle safety design.