Airbags celebrate 25 years

The silver car turning right across the other side of the intersection is obviously facing a red arrow — no danger there, you think.

You're halfway through the intersection before you notice something's not right. You see a flash of silver out of the corner of your eye. Then comes a sickening crash and a wall of white.

Maybe you were in the right and the other driver in the wrong. Maybe you've never made a mistake while driving and own the most nimble car with the best handling you can afford.

But sometimes there's nothing you can do. Your only protection is how well the car protects you in a crash.

Research proves airbags are a key part of that.

This year the SRS (secondary restraint system) airbag celebrates its 25th birthday. In 1980 it was installed for the first time in a passenger car — a Mercedes-Benz S-Class.

It had a controversial beginning. Doomsayers said they would kill more people than they save, but today airbags are as essential to road safety as the seat belt.

Now, not a single car sold in Australia doesn't have at least one airbag. Many have six or seven.

There can be only one reason for the success of the airbag: it works.

In a real-world investigation, Monash University Accident Research Centre (MUARC) took the results of 155 frontal crashes involving airbag-equipped and non-airbag-equipped Holden Commodores between 1988 and 1999 and compared them.

The survey found the driver airbag reduced the severity of head injuries by 75 per cent, facial injuries by 51 per cent, neck injuries by 70 per cent and chest injuries by 47 per cent.

Ross McArthur, manager of vehicle safety and chairman of the Australian New Car Accident Protection (ANCAP) steering committee, explains.

"I've been involved in road safety since 1980 and I would say airbags are one of the three best things I've seen. The other two are seat belts and, lately, stability control," he says.

"Statistics from actual crashes tell us airbags in the front reduce injury risk by 50 per cent. They also tell us side airbags can reduce injury by up to 40 per cent, so they are very effective indeed."

McArthur is so convinced of the airbag's merits that he says it should be a major consideration when buying a car.

"It's at a stage now where people should steer away from any vehicle, new or used, that doesn't have a driver airbag," he says. "If I were buying a new vehicle, it would have head-protecting side airbags as well."

The development of a safety cushion that could be deployed in a micro-second in a crash began in 1967. But the program nearly foundered when a tester died in an airbag-related accident.

It wasn't the last time the safety of airbags came under scrutiny. In a minor collision, a child was decapitated by a front-passenger airbag.

"That did happen," Australian airbag pioneer and chief engineer at Holden Innovation Laurie Sparke says. "That particular accident happened in a parking lot at only 5km/h.

"Rule No.1 is children under about 12 should always be in a back seat and always wear an appropriate restraint. Children should not be in the path of an airbag."

Airbags are an explosive device. When sensors detect a crash, they trigger a discharge that inflates the airbag within 50 milliseconds, half the time it takes to blink your eye.

The airbag comes out at approximately 200km/h and needs 200mm to inflate, which is why small children or anyone without a seat belt is at risk.

The reality, though, is even the worst airbag ever installed has not adversely affected passenger safety.

"The American systems were never as good because they were compromised by having to take into account people who did not wear seat belts," Sparke says.

"These days they're better because airbags have sensors to show if the person is wearing a seat belt.

"But airbags benefit those who wear seat belts anyway."

Australia was a world leader in airbag technology, according to Sparke, who was awarded the Order of Australia Medal (OAM) for his work in car safety.

He says Holden has made the running on the technology, both locally and internationally, since 1995, and that Ford and Holden have worked together with safety supplier Autoliv.

"At the time we were developing the VR Commodore airbag they were fashionable but not very successful," he says.

"With MUARC, we came up with a formula called Harm (hospital costs, rehabilitation costs and monetary loss) to measure the injury costs of crashes and the effectiveness of airbags, and we used it in our development.

"After it was published, a United States Senate subcommittee on road safety got in touch with us wanting to know how we'd achieved that degree of improvement, especially for small occupants.

"As result of Australian input, the US Senate changed the airbag performance requirements.

"It's interesting that Australian technology drove American legislature."

• AIRBAG FACTS

   

• An airbag deploys in 50 milliseconds, half the time it takes to blink.
• Once an airbag has deployed, it and the control unit must be replaced.
• On A Holden Commodore Executive, front airbags cost about $500, side airbags $250 and the control unit (mounted under the seat) about $300. Holden's Laurie Sparke says airbags now cost about one 10th of those in the early '80s.
• About 50 per cent of crashes severe enough to deploy an airbag result in the car being written off.
• The cost of replacing airbags is usually insignificant compared with the cost of repairing damage to the vehicle.
• It's rapid acceleration or deceleration that sets off airbags, not the impact itself.
• Race cars are rarely fitted with airbags, partly because drivers wear helmets and full harnesses.
• They have been used by Mercedes-Benz in the DTM (German Touring Car Championship). V8 Supercar veteran John Bowe says they should be considered in Australia.
• The Lexus GS is Australia's airbag king with 14, including driver and passenger knee-protection bags.
• People who see an airbag deploy are often startled by a cloud of white dust. This is cornflour, which acts as a lubricant when the airbag deploys.