What safety device in emergency vehicles protects against sudden stops?

The data recorder, often referred to as an event data recorder or crash data recorder, plays a significant role in analyzing incidents after they occur. It collects and stores crucial information about vehicle dynamics, speed, braking, and other parameters during an event, which can be invaluable for understanding what happened during a sudden stop or crash. However, while the data recorder is essential for post-incident analysis, it does not actively protect occupants during a sudden stop.

In terms of safety devices that actively protect against sudden stops, seat belts are designed specifically to restrain passengers within the vehicle, reducing the likelihood of injury by preventing them from being thrown forward or sideways during abrupt braking or collision. Airbags deploy upon impact to cushion and protect the occupants from striking hard surfaces, further contributing to vehicle safety.

The steering lock, while it has its own function of preventing unauthorized use of the vehicle, does not provide protection to occupants in the context of sudden stops.

Therefore, when considering safety features designed to actively protect occupants during sudden stops, seat belts represent the most effective choice.