Thursday, February 12, 1998 Published at 10:01 GMT
How the dead have helped the living
Test dummies were based on experiments with humans, both the dead and the living
Car safety has come a long way since the first man died in a car crash 100 years ago. But behind every sleek safety device, gruesome experiments have been conducted using human cadavers, animals and even living people. BBC producer Sam Roberts, who recently made a film on the subject for the science programme Horizon, tells the story of the work that has gone in to making our cars safer.
Safety engineers have tuned the padding on the dashboard, the strength of the seat belt webbing, the stiffness of the steering column, the thickness of the windscreen glass, and even the rear view mirror mounting, according to how much of an impact the body can withstand without being seriously injured.
If you want to build a dashboard which doesn't fracture the skull when a head slams into it in a crash, you need to know how much of a blow the head can take without being fractured. The padding must be as stiff as it can be - make it too soft and in a high speed crash, the head will plough right through, into the metal behind. Make it too hard, and even at low speeds it may cause fatal brain injuries.
Well into the 1950s, car manufacturers tended to claim that accidents could never be made survivable - the violence was simply too much for the body to bear. But they were wrong.
Most of the information has come from subjecting the bodies of the dead to simulated collisions on high speed sleds. Nowadays, crash test dummies are used to fine tune new designs, and to provide repeatable standardised tests for new cars. The dummies are based on real human bodies.
Cadaver testing has continued ever since. It's not something we have done in this country - we draw the line at using parts of corpses to study injuries to the legs, for example. But all manufacturers make use of the data from the experiments performed primarily in the USA, France, Germany, and Japan.
Everything from the larynx to the patella has been smashed. Techniques have become more sophisticated in an attempt to make the results more representative of living human beings. The blood vessels are sometimes pumped full of dye under pressure to study injuries to internal organs - the spread of the dye shows where vessels have ruptured.
Cadaver testing has always been a delicate issue. Despite the vital information crash injury research has produced, it's never been fully accepted that this is a fitting use for the dead.
The issue isn't about to go away. Despite thirty years of cadaver research there are many questions still unanswered. There's been great progress in preventing fatal injuries to the head and chest, but for every person killed in a crash, a hundred are seriously injured - often with crippling damage to the legs and feet. Designing cars which produce fewer severe injuries is the next challenge.
And there are the children. Child crash protection is hampered by the lack of information about children's tolerance to impact - and the only way to provide that data is to perform experiments on dead children - which at the moment, none of the major car producing nations will permit.