Keep car contents to a minimum to avoid crash injuries

Your vehicle has all kinds of safeguards in the event you become involved in an crash, from seatbelts and air bags to rollover protection and energy-absorbing structures that divert the shock of impact around the passenger compartment and not through it.

That's great news for impact that originates outside the vehicle, but not for the potential disaster waiting inside the vehicle from loose objects. Unlike a crash with another vehicle, there's almost nothing to separate you from impact from stray tools and ice scrapers to books and hardware purchased on a quick jaunt to the local home-improvement store.

Flying debris inside the vehicle can lacerate flesh and break bones because there's nothing -- or almost nothing -- to stop it.

According to a report aired on weekly half-hour TV show entitled "Fifth Gear," there's surprisingly little crash data on the subject, which is why the show's producers set about to smash a car with a variety of seemingly harmless items loosely placed inside the cabin. Although not considered scientific, the tests demonstrate one very crucial thing: If running into something outside the vehicle at 30 mph can kill you, that goes double for objects located inside the vehicle.

It's tough to quantify exact human injury since the vehicle used was older and presumably not as structurally sound as a newer vehicle, and because there were thankfully no people inside the car during impact.

Consider this, however. According to the report, a 30-mph direct hit (two vehicles colliding head on at just 15 mph) produces an impact load of 30g's. That means whatever the object weighs at rest is multiplied by 30 times. A 15-pound tool kit in the trunk thus has a force of 450 pounds at impact, enough, according to the test, to split the rear seat right down the middle and head like a missile for the front-seat occupants.

Even an innocent-looking hard-covered atlas located on the rear parcel shelf, where many people like to pile junk, rocketed forward with enough impact to shatter the windshield.

The most harrowing of the tests simulated a weekend run to the home-improvement store, certainly my favorite past time these days. The back seat was folded forward to accommodate a number of items, such as several flat-packed boxes (the same way a typical bathroom vanity would be packaged, for example) and a stainless steel double-wide kitchen sink.

The results were chilling. After impact, the interior was nearly unrecognizable: a stew of interior pieces, smashed seats, disintegrated plastic and shattered glass.

As positively shocking a sight as it was, thinking what might have happened had there actually been passengers aboard, it makes total sense. That 40-pound box holding a new bathroom vanity in a box catapults toward the front of the vehicle -- and you -- with a new weight of 1,200 pounds. At that's at 30 mph combined speed.

There's a clear plan of action, however, some good news and solid lessons learned from the exercise. The lower the object was placed in the vehicle, such as on the floor behind the front seats, the less the damage that occurred.

Items in the trunk appeared to have a harder time entering the passenger compartment when the rear seat belts were latched (even without rear-seat riders).

Keep absolutely everything off the rear parcel shelf, since it's right at head height. Those of you who drive around with Fluffy (cat or dog) in the back window need to seriously rethink the idea of a travel kennel.

And if you like to pick up do-it-yourself projects from the building-supply store, pay a few extra dollars for delivery, even if it means waiting a few days for your stuff to arrive.

Most importantly, remember that items that appear harmless at rest can turn into deadly projectiles during sudden stop. Think of being struck in the back of the head with a hardcover road atlas that's traveling 30 mph through the air.

That means clean all the junk out of the car, including the trunk, that isn't absolutely essential to traveling and stow everything else.

It's about time we paid attention to loose items in the cabin as much as the number of airbags there are in a new vehicle, since, ultimately, it might be just as much or even more relevant.

Rhonda Wheeler is a journalist with Wheelbase Communications, a worldwide supplier of automotive news, features and reviews. You can e-mail her by logging on to www.wheelbase.ws/mailbag.html.