Winter Coats and Car Seats - Check for Safety!

Thick Coats and Snowsuits Reduce Car Seat Safety

Winter Coat Car Seat
Getty/Tanya Little

As the coldest part of winter approaches, parents everywhere bring out their babies' winter coats or snowsuits to keep baby warm during travel. However, thick winter coats or snowsuits can compromise your child's car seat safety. In order for a baby car seat or toddler booster seat to function properly, the straps need to remain tight against the child's chest.

Winter coats and snowsuits make car seat safety difficult because they change the way a child fits into the car seat. When the car seat straps don't fit the child properly, there is a chance the child could be ejected from the car seat.

Coat Compression is Dangerous

Why is it unsafe to put a thick coat, snowsuit, or blanket on under the harness of a car seat? In a crash the coat could compress, making the straps too loose and possibly allowing the child to be ejected from the seat.

The car seat harness needs to stay close to the child's body at all times. All coats and clothing will compress in a crash, but thicker winter coats and snowsuits could compress enough to create a lot of slack in the harness. The effect could be as though you never tightened the harness straps at all. Those loose straps may not be able to keep baby in the car seat, or in the car at all.

Check All Winter Coats for Car Seat Safety

It's easy to check and see whether a baby's winter coat or infant snowsuit is too thick to be safe in a car seat.

This test will show you how thick the coat is and how much the coat will compress during a crash.

  1. Take the car seat into the house.
  2. Put the winter coat or snowsuit on the child.
  3. Put the child in the car seat and buckle the harnesses as you normally would before car travel. Adjust the straps to the appropriate fit for your child.
  1. Take the child out of the car seat without loosening the straps at all.
  2. Take the coat off your child.
  3. Put the child back in the car seat and buckle the harnesses again, but do not tighten the straps.
  4. If you can fit more than two fingers under the harness at the child's shoulder bone, the coat is too thick and is not safe for use with the car seat.

Keep Baby Warm and Safe

Even if you can't safely use your child's winter coat in the car seat, there are ways to keep baby warm when temperatures drop.

  • For babies in an infant seat, dress them warmly in normal clothes, like a shirt, sweatshirt, long pants and a hat. Buckle the child into the infant seat, then cover the baby with a light blanket tucked around the sides. Make sure nothing is behind baby's back! Finally, add another heavier blanket over the top of the infant seat.
  • Also for infant seats, there are car seat covers available that fit over the whole infant seat once the baby is buckled in. These covers have a peep-hole so that baby's face remains uncovered. Ellis advises parents to be sure the child is buckled up under the cover, though, as it's easy to forget when the buckle is out of sight.
  • For older babies and toddlers, take the child's coat off before buckling them into the car seat. Once the harnesses are secure, put the child's coat on backwards over their arms to keep them warm without compromising safety.
  • Whenever possible, warm up your car before putting the baby in the vehicle.
  • When buying winter coats, keep thickness and car seat safety in mind. Polar fleece jackets and snowsuits are warm but thin, making them a smart choice for winter baby wear.

A Real Life Example

In order to become a certified CPS tech, Jen Ellis, a mother and certified Child Passenger Safety Technician from Meridian, Idaho, had to take an extensive car seat safety course and pass both a written exam and hands-on car seat installation exams. "When I took my tech class we were shown a picture of an infant seat with a snowsuit under the harness," she says.

"The seat was pulled out of a car that had just been in a crash. The infant was ejected from the seat and the car and was found some feet away from the car, but the snowsuit was left in the seat just as the baby was wearing it."

Ellis says other parents can learn a valuable car seat safety lesson from this real life crash story. "It's a great example of what can happen in a crash if the straps are not tight enough and if a thick blanket or coat is under the harness," she says. "The harness must stay close to the child's body at all times."

A Note on Car Seat Covers

Many companies also offer thick car seat covers that act like a bunting for babies in the winter. Parents should avoid buying any car seat cover or car seat bunting that threads through the harness straps of their child's car seat. Often the packaging of these covers states that the product meets all federal car seat safety guidelines. However, there are no federal guidelines governing after-market accessories. These extra car seat covers and buntings could interfere with the function of the car seat harness, and many car seat manufacturers will void your car seat warranty if after-market accessories are used. Winter car seat covers that fit over the top of the car seat like a shower cap or drape can usually be used safely, though.

Baby Products Guide Heather Corley is a certified Child Passenger Safety Technician-Instructor.