In Hollywood fashion, the campervan left the dirt road and began tumbling 30m down a sheer slope.

It rolled over five or six times, crashing through the undergrowth before coming to rest at the bottom of the ravine, wheels pointing skywards.

I thought I was a goner, but I walked away from the crash - thanks to the humble seat belt.

My passenger, who was also buckled up, emerged shaken but unharmed.

That incident, which happened in New Zealand some 20 years ago, convinced me beyond doubt that seat belts work. (The vehicle would not have skidded if it had anti-lock brakes, but that's another story.)

As a motoring journalist, I have come across repeated examples of how belting up is one of the best ways of avoiding an early date with the Grim Reaper.

One Malaysian motoring writer survived unscathed when the BMW he was testing in Spain had a head-on crash with a truck.

Once, while enjoying a new Jaguar in a quiet French countryside, I was overtaken by a writer from Korea. He must have been doing 120kmh in a 50kmh zone.

Moments later, he lost control and the car crashed into an embankment. The driver got out, bruised by the airbag, but very much alive.

If he had not belted up, the airbag would not have saved him. In fact, the device, which deploys with explosive force, might have opened up in his face with the force of a flying brick.

In the 1990s, when airbags were commonplace in the United States, there were numerous cases of carmakers being sued over injuries and deaths resulting from airbags.

Ironically, the casualties were mostly not buckled up. Or they had the childseat facing the wrong way. (The right way: the child must be facing rearwards.)

Contrary to popular belief, airbags do not function as substitutes for seat belts. They supplement them.

In 1997, the importance of belting up - even if you are seated in the rear - came to the fore starkly when Princess Diana died in a horrific car crash. She and her boyfriend Dodi al-Fayed had not buckled up.

I happened to be in Paris the week after the accident and had the chance to visit the crash site, along with hundreds of other gawkers. I wondered how many came away with the safety lesson of the day.

Yes, there have been cases of people being injured despite the use of seat belts. American supermodel Niki Taylor was one. She was in a car crash in 2001 which left her with a badly bruised liver. But she was soon back on her feet - no worse for the experience.

If she had not belted up, one of two things would have happened: She would have been thrown out of the car; or she would have hit something (or someone) in the car.

It has been calculated that a three-year-old weighing 12kg flung from the back seat can gather a force of up to 1.2 tonnes.
He will either crash through the windscreen, or hit something (or someone) in the car.

The current call for seat belts to be fitted in school buses is not new. The Land Transport Authority has been planning to make them mandatory since 2002.

One of the main hurdles cited: Cost. Firstly, the seating arrangement on most buses would have to be reconfigured to allow proper harnesses - and not just token lap belts - to be bolted on.

Secondly, operators would not be able to squeeze as many children into a bus as they now can.

Are parents willing to share the bill for safety, even if the probable fee hike per child is incremental?

Is the Government willing to offer some subsidies on account of potential cost savings accrued from lives and limbs spared? And why not, if rebates are granted for "green" vehicles?

Road safety extends far beyond seat belts, of course. There's the general standard of driving, for instance, which, in my mind, has gone completely to the dogs in recent years.

Inconsiderate, careless and downright reckless habits abound. Combine that with a cohort of newer drivers and those who are new to the roads here, and you have a pretty volatile mix.

You don't have to take my word for it. Just ask the insurance companies. Last year, they received over 151,000 accident reports - the highest in five years.

As for the two cars which collided with eight-year-old Russell Koh's school bus two weeks ago, do the drivers share the blame for his death?

Whatever the answer, a seat belt might have prevented the tragic outcome of the crash. That much is certain.

This article was first published in The Sunday Times on May 4, 2008.