Driving - A Risky Business

The simple act of filling your car with petrol has become so utterly mundane that few of us are aware of the staggering volumes of energy being transferred every time we interact with a petrol bowser.
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Every 25ml of petrol, which you could hold easily in cupped hands (although the World Health Organisation recommends abstaining from skin contact) contains about 800kJ of stored energy – about the same as a Holden Commodore or Ford Falcon traveling at 100km/h. And if you’ve ever searched YouTube for that famous Commodore-hits-wall-at-100km/h crash-test footage you’ll see just how much destructive potential there is when 800kJ goes horribly wrong.

(Incidentally, this is why it’s a major judgement error to try lighting the BBQ with a cupful of the stuff – that’s a ticket on the express to Molotov City. But it could improve the gene pool, overall.)

So even a small, 50-litre petrol tank contains the destructive potential of about 2000 large family cars all impacting the same point at 100km/h. Good safety tip: petrol deserves respect.

The energy stored in our common liquid fuels is gobsmackingly immense. The kerosene in just one torpedo (the fuel, not the explosive) was enough to destroy The Kursk, a Russian nuclear submarine bigger than a Boeing 747 and built to withstand extreme hydrostatic pressure. It’s a real miracle that the 20 billion-ish litres of petrol regularly de-canted by an untrained and unaware populace at servos across Australia hardly ever results in Hindenburg-esque drama.

The reason fuel handling is so apparently safe is simple. Two words: systematic protection. The refueling process involves interacting with a system carefully designed to prevent disaster. So long as you’re not holding the Olympic Torch with your other hand, it’s probably reasonably safe.

When you get out of the car at the servo, you touch both the car (undoing the filler cap) and the fuel nozzle handle (grabbing the pump). This equalizes the electrical potential of you, the car and the pump before there’s fuel vapour wafting around, preventing a static electricity spark. (Sparks can only jump between bodies with different potentials.) The nozzle itself is in contact with the filler neck during the refill, preventing a charge from building up as you fill, and the flow rates of the fuel are designed to prevent a charge building up in the liquid itself as it flows. (Perverse fact: liquid petrol can carry a static charge.) There are even emergency shut-off valves that stop a fire at a bowser or elsewhere on the forecourt from spreading to the large storage tanks underground.

So, filling up comprises a multi-layered safe system. Even so, however, static electricity is the commonest cause of service station fires. These are low-probability events with high consequences. And they usually occur because human dumb-ness knows no bounds. From time to time (rarely), some dumb-ass manages to overwhelm the protections built into the system and send himself on a little holiday to the burns unit of the nearest big hospital.

It usually happens when filling a portable fuel container. And the newsflash there is always to put the container on the ground near the pump before refueling it. This earths the container to the same potential as the pump, preventing a spark jumping between the two at an inopportune moment – such as when highly explosive fuel-vapour/air mixture is spewing out. If you refuel a jerry can or the mower container while it’s sitting in the back of your ute, in the boot, or in a box trailer, caravan, etc., you risk blowing yourself up – it’s that simple. People do it on a semi-regular basis, even though the servo console operator isn’t supposed to activate the pump if they see you putting yourself in this dangerous situation – yet another inbuilt protection in the system.

For a system to be really safe, however, there must be human safeguards overlaid on top of all the inbuilt systematic stuff. And I’m not just talking about refueling; I’m on about driving as well.

Although the regulators claim speed is the commonest factor in road trauma, the reality is that intersections are really the biggest contributor. (This is why freeways are so safe – despite the relatively high speeds, grade-separated interchanges replace ordinary flat intersections. And that prevents vehicles traveling in different directions from crossing paths.)

An incredible 50 per cent of road trauma happens at intersections. And it doesn’t occur because of a defect in the rules. The rules governing traffic flow at intersections are completely robust. There’s no flaw permitting vehicles traveling in different directions to occupy the same space at the same time.

Yet crashes at intersections happen all the time – to the tune of about $10 billion annually, comprising about 800 deaths and 10,000 serious injuries.

It happens because human protections fail. People drive through stop signs/red lights, etc., when they should give way. They make mistakes. Maybe they’re angry, distracted, fleeing the cops, picking up a dropped baby’s bottle, rolling a joint or re-loading their Beretta. Who knows? And – here’s the main point – the other driver in the crash doesn’t a) acknowledging the risk in the first place and b) taking preventative action to mitigate it.

See, it’s pretty common to drive through a green light safely. Of all the millions of movements through intersections daily, only a tiny fraction go wrong – low-probability, high-consequence events. Most of the time drivers in the opposing traffic flows stop and give way as they should. Occasionally someone doesn’t, and if you steam on through on the green at exactly the wrong moment, without checking, you’re suddenly a statistic. Experience told you to expect the best (compliance/safety) and what you got was in fact the worst (non-compliance/crash). And it’s not much fun being notionally in the right if you’re also in hospital, for example, and unable to feel your toes.

What drivers must do is acknowledge that, from time to time, rules get broken. That’s part of the system, too. We have to act to protect ourselves from situations where the rules don’t get complied with.

As a journo I once spoke to a chap on the brink of death in a trauma centre, fully conscious but slightly disoriented and lying in a resuscitation bay, a hole ripped inconveniently in his heart from being T-boned in exactly this situation. The rip in one of his heart’s chambers meant blood was leaking into the pericardium (the sac that encases the heart) slowly squashing the heart with the very fluid it’s meant to pump.

This problem is called, in the vernacular, a cardiac tampenade, and it’s not a nice way to spend your Saturday afternoon. We chatted briefly (I tried to be optimism personified; we both knew it was a sham) while the trauma director told a nurse to “get the tray”, which I later learned was trauma centre shorthand for the ‘thorachotomy tray’, a macabre assortment of the tools required to crack a human ribcage open in the event he crashed and they had to fix him then and there, before an operating theatre became available.

During our brief and faux upbeat discussion it became pretty clear that this certainly wasn’t how he planned his day. Big consequences often flow from small mistakes. A few minutes later I rode up in the elevator and watched two highly skilled and in my view utterly heroic surgeons get the plumbing under control – successfully as it happens. A humbling, uplifting experience. Unfortunately, many stories like this don’t always end as happily.

After a couple of glasses of red, a paramedic I know tells a gripping, if black, story about a motorcyclist who T-boned a car at an intersection (sorry mate; didn’t see that red light). He turns up on the scene and the rider’s suffered a ‘bilateral tension pneumothorax’ – two collapsed lungs – and ‘bilateral traumatic amputations at the femur’ – both legs cut off in the crash, at the thigh. That’s bad. Amazingly, he kept the unfortunate victim going until the hospital, but the injuries were too great and the motorcyclist succumbed to them.

The bottom line is that prevention beats cure, or attempts at same, hands down.

What’s got me stumped, basically is why the licencing process teaches only the rules (red light means stop, T-intersection ‘give way’ protocols are…, etc.). You can get your licence in this country without ever being told a simple safety check before proceeding into an intersection can halve – yep, halve – the risk of getting hit by road trauma.

It’s fine to build better roads and safer cars, but until the authorities come to grips with drivers – equipping them with strategies and safeguards for really boosting safety, such as the ‘look both ways’ widget for intersections, above, more preventable trauma will keep happening. It’s hardly advanced driving, is it?