George Clark of Wisconsin should know. He and some fellow dads were coming home from Boy Scout Leader training when another car pulled right into their path. They hit it going 50 miles per hour and the untethered child booster seat next to Clark slammed into his head, crushing his cheekbone and jaw.
"I basically had facial reconstruction," Clark said of his recovery. "In today's environment, with the airport security, I probably look like the terminator."
"Very Humpty Dumpty," his wife Lynn Clark said. "That's exactly what it must have been like for him to put all of these crushed pieces of bone back together again."
Safety Research and Strategies, an accident investigation company, estimates ordinary objects in cars are responsible for 13,000 injuries a year.
At 55 miles per hour, a 20-pound object hits with 1,000 pounds of force -- so powerful that a suitcase can literally sever the arm of a crash test dummy.
"From head impacts to serious internal injuries, it's a wide range depending on the severity of the crash," Sean Kane of Safety Research and Strategies told "GMA."
One study showed how unbelted passengers are a danger not just to themselves, but to others -- because people can become projectiles themselves.
"Even something as small as a can of peas can become dangerous," Clark said.
As for Clark, he's had multiple surgeries and racked up more than $60,000 in medical bills.
He said he wanted his story to be your cautionary tale.
If you have a summer roadtrip planned, you might want to re-think how you're going to pack the car. Here's some more advice:
Check your owner's manual to find out the weight limit for your vehicle. Even giant SUVs shouldn't be overloaded.
If you're going to strap some belongings to the top of your car, make sure they're no higher than 18-inches and no heavier than 100 pounds. Too much height and weight can contribute to a rollover.
Whether it's groceries day-to-day or suitcases on a roadtrip, first storage choice should be the trunk of the car. That way there is no way for those items to fly up and hit you.
If you're driving a minivan or an SUV, learn to love the anchors and tethers that come with the vehicle or buy some aftermarket ones. You want to secure all the objects in the back of your vehicle this way.
Now let's talk about the booster seat issue. Booster seats are just supposed to raise kids up so an adult seatbelt fits them properly. They are not attached to your car in any way. (I prefer a jumbo-sized car seat for older kids that is attached, but that's another story that we've talked about before.) To keep the booster from going airborne when there's no kid in it, ideally you would remove it and put it in the trunk. If that's not possible, you want to buckle it in with the seatbelt just as you do when a child is using it.
Since even small items can hurt you when they take flight during a crash, you'll want to make frequent enough stops to get rid of your trash. Clutter is not a good idea.
You want to put heavy items, such as loaded coolers, as far forward as possible, so if you slam on the brakes, they don't have far to travel. And you want them low and centered. If they're high and to the side they can contribute to rollovers, so on the floor near the front is best.
Moving up to the driver's seat, you want to have essentials like your cell phone, sunglasses and maps in arm's reach for safety's sake, but it's best not to keep them out. Just get in the habit of tucking those items in the console right next to you, instead of leaving them lying on the seat.
Keep the pressure on.
Under-inflation and tire tread may not seem like a big deal but tire maintenance is important for the safety of your family. Underinflated tires can cause handling problems, or even a blowout. Overinflation causes the center of the tire to bulge out and rub the road unevenly, wearing your tires our prematurely.
Do the Lincoln vs. Washington tire test.
To get the best handling during sudden downpours, which are common in warm weather, TireRack.com recommends replacing your tires when you have an 8th of an inch of tread depth instead of the traditional 16th of an inch, outlined in the penny test.
TireRack.com has shown that the penny test -- where you insert a penny into your tire tread with Lincoln's head facing down and if the tread touches the tip of Lincoln's head, you have a 16th of an inch of tire depth, which is the minimum -- can show tread that is not robust enough for heavy rain.
Instead, they suggest using a Washington Quarter to test your tires. If your tire tread touches the tip of Washingotn's head, you have an 8th of an inch of tire remaining.
Here's a good tip to keep your tires in better shape longer: avoid potholes, and if you can't, slow down as much as traffic allows before hitting them. Rolling over just a single pothole can reduce a tire's durability, knock the vehicle out of alignment and reduce the overall ride quality.
Whenever you see road construction, be on the lookout for uneven lanes that sometimes have sharp edges where the old pavement was ground away. It can be a two-inch difference between lanes if the crew hasn't been able to smooth the transition between lanes. Be prepared for the change and slow down a bit when transitioning to make sure you keep control.
If you'd rather avoid it all together, TripTik Travel Planner on AAA.com can help you avoid construction-caused congestion.
Just like a cooler can become a projectile in the car, an unsecured animal can cause injury to itself or the human passengers during a crash.
You may want to consider a seat-belt harness that can keep the pet in place or a pet barrier that separates it from the human passengers.
An unsecured animal can become a dangerous projectile in a crash, risking injury to itself and the human passengers. To reduce those risks, consider a seat-belt harness that can keep your pet restrained or a pet barrier that keeps the animal safely contained behind the rear seat. There are also mats and liners available to protect your seats from scratching, drool and other pet wear.
The best way to avoid being singled out for robberies is to try and look like a local -- regardless of your license plate. Try not to leave road maps in plain sight. A car packed with luggage is also an obvious giveaway, so take what you can out of your car and into your hotel room at night.
It's also a good idea to tell friends or family where you plan on going and when so someone would know when something is wrong.