IF YOU HAVE a roof box like the one seen in the above video, you really need to be careful about how you pack it.

A crash test conducted by Allianz has shown how quickly a poorly-loaded roof box can add to the potential injuries of a car crash. The test was conducted using a standard 380 litre box packed with skis and associated equipment.

Allianz said a crash can cause these boxes to explode upon impact and spew their contents with the force of several tonnes due to the impact in a car crash.

In effect, it becomes a cannon.

“In a crash of 30 miles an hour, where the car suddenly goes from 30mph to 0 mph, the contents of the car roof box will retain the force of travelling at 30 miles per hour. Your car takes 3 seconds to stop when you brake at 30mph, but in a crash that time can shorten to .01 second meaning the force can be up to 150 times the force of gravity”, explained Brendan Murphy, CEO, Allianz Ireland.

“A 380 litre box with a load capacity of 60kg, under 150 times the force of gravity can become a cannon and shoot out contents, which could add to injuries sustained during a car accident.”

For those of you with roof boxes, Allianz has these tips for safer driving:

1. Check your car’s manual to make sure that the load, including the weight of the roof rack itself, doesn’t exceed the maximum. This limit tends to be quite low.
2. Be aware that a fully loaded car (with or without a roof box) will require more braking distances.
3. Under heavy braking the load will tend to slide forwards – accelerate and brake gently.
4. A roof box can alter your car’s centre of gravity so take corners at a lower speed.
5. Put heavier items at the bottom of the roof box and lighter items on top.
6. Do not exceed the recommended load capacity of a roof box.
7. Don’t forget the extra height when entering underground car parks or entrances with lower height.
8. Take care, for example, when entering covered car parks.
9. Distribute weight safely in a roof box.
10. Check your tire pressures – consult the manual to see if you need to increase or decrease your tire pressures to cope with the extra weight.

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