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

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.

With all the sensors and technology built into a crash test dummy, why would a human occupant yield better crash test data? Crash test dummies are very good about showing how much force impacts a body during an accident. What they can't do is show how much force a human body can reasonably expect to take without getting injured. If actual humans weren't crash test dummies, scientists wouldn't have data to judge the forces in a crash as safe or unsafe.

There are also a few things crash test dummies can't do. Namely, they can't react to the impending collision. When people are in a crash, they instinctively tense their muscles. That's something a dummy can't do, and it's something that could also lead to injury during an accident. Crash test dummies also don't have skin -- and many of the injuries in an accident are cuts and abrasions.

That's where human crash test dummies come in. Human cadavers were first used in crash tests long before crash test dummies were invented. Occasionally, cadavers are still used today, although most automakers and research institutions don't like to talk about it. It's a lot more fun to talk about living human crash test dummies.

While uncommon, these volunteers participate in slow speed crash tests to provide invaluable data to crash investigators and engineers. Still, these tests aren't without problems. For one, constantly experiencing car crashes, even slow ones, takes a toll on a person. There are also ethical considerations: The quest for data can overshadow the need for safety. Though the crash tests are very controlled, and every precaution is taken, there is always the risk of severe injury or even death for the human tester.

So the next time you crash after a hard day's work, be thankful it's only an expression. For some people, crashing is part of the job. For more information about crash testing, automotive safety features and other related topics, follow the links on the next page.

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