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Have crash tests ever used live (or dead) human occupants?

Engineering Dummies
A pregnant crash test dummy is fitted with a seatbelt prior to a test.
A pregnant crash test dummy is fitted with a seatbelt prior to a test.
Andy Sacks/Getty Images

The purpose of crash tests is to gather data - not just about the car's systems, but about the effect of the crash on the people in the car. Some of the effects are obvious. In a crash, people in cars are exposed to physical force and as a result they usually get tossed around. That's obvious. Crash testing studies the forces car occupants are exposed to during a crash in a controlled, measurable environment. The data crash tests gather is so precise, it can help develop new and better safety systems.

Some of the most specific data in a crash test comes from the dummies themselves. Crash test dummies are engineered to mimic human physiology and to approximate what a human body endures during a crash. The dummies have sensors throughout, which allow crash test engineers to see exactly what forces the dummy was exposed to and how strong those forces were.

A lot of engineering goes into crash test dummies. They come in different sizes and shapes, to show what might happen to men, women and children in accidents. Crash test dummies can be overweight, thin, tall or short. Scientists have even developed a pregnant crash test dummy to study the effect of car crashes on pregnant women and their unborn babies.

But as advanced as crash test dummies are, they can't tell researchers everything that happens in a crash. That's why some people suit up and strap in as human crash test dummies. Read on to find out how and why they do it.