When you strap your kids into their car seat, you’re doing it to protect them. But little did you know that in the winter time, this can prove to be a dangerous habit. It seems counter-intuitive, but being aware of this strange occurrence could save your child’s life.

Studies have found that your child’s thick winter coat can cause seat straps to loosen, therefore turning the seat into a terrible safety hazard. While the straps might seem taunt against your their jacket, the coat is causing an optical illusion of sorts. In reality, the seat belts are just expanded to the thickness of the coat and are not firmly keeping your child in their seat.

If you remove your child from the car, take off their winter jacket, and the put them back in the car seat, you’ll notice that the straps are extremely loose. So loose that they could barely hold a kid in place if the car were to crash.

This horrible truth is demonstrated by a few tests with a child crash dummy. Upon “impact” in the test car, the child dummy (wearing an actual, child-sized winter coat) goes flying forward, right out of the too-loose seat straps.

And this test was only conducted at 30 MPH.

So what can parents do to assure that their kids are safely strapped in this winter? There are a few ways to tell if your child’s safety belt is actually holding them in or not; for example, there should be no slack by the top of the belt and the buckle should be at armpit level for your kid.

But to be especially careful, try not to strap your child into their car seat with a puffy winter coat on. Keep their jacket on hand and take it off right before putting them in the car, and be ready to put it right back on when you take them out.

You could even go the extra mile, going out and warming up the car minutes before you’ll be strapping your child in! This will ensure their safety and their warmth in the chilly months to come.

To keep your child safe this winter, it’s extremely important to be aware of this unknown danger! What do you think of this safety tip? Share your thoughts in the comments section below.