Car seat safety professionals will tell you they see a lot of car seats installed incorrectly, and very few done right. The fact is, “the overwhelming majority of car seats are mis-intalled,” says Ben Hoffman, M.D., an associate professor of pediatrics at the University of New Mexico in Albuquerque, and a certified child passenger safety technician and instructor. That means most of us are driving around town with seats that could be more dangerous than not using one at all.

The most common mistakes Hoffman, Baer, and Walker see are:

1. Routing seatbelts incorrectly
2. Not putting seatbelts in lock mode
3. Using both the lower anchors of the LATCH system and the seatbelt
4. Connecting the lower anchors and tethers of the LATCH system to the wrong points in the car, especially cargo hooks
5. Forgetting to use the tether at all (See Mistake #6 for more on that)
6. Not putting enough weight on the seat as it is being installed

Fixes:

1. Read BOTH your car seat’s manual and your car’s manual.

2. Decide whether you will use the lower anchors OR a seat belt, and follow the directions for only that method. (The lower anchors are part of the LATCH system, which stands for lower anchors and tethers for children). Once you’ve connected the lower anchor straps, pull the belt tail tightly from the top of the car seat, not the side.

3. If you are using seatbelts, figure out if yours are self-locking (they are required to be in any car made since 1997) and, if they are not, very carefully read how to use either the metal locking clip that came with your seat or the seat belt lock-off (if there is one) built into the car seat.

4. If you are using the lower anchors, make sure you are using the proper anchors for the seat position you have chosen in the car (your car manual will tell you which ones). Many people think their vehicle has lower anchors for the center seat, but most cars don’t.  Parents often mistake anchor on the side seats for ones that belong in the center.  Make sure to tighten the straps once the clips are locked into place.

5. Know that installing a car seat will take a bit of brute force, so try to put as much of your weight as possible on the seat as you install it. For rear-facing convertibles, try leaning your stomach on the back of the seat; for forward-facing, put both of your knees on the seat and then secure it. With your weight on the seat, wiggle the seat down into the cushion. Many installations are easier when done with two people.

6. When you’re done, hold the seat where the vehicle or LATCH belt is holding it and really give it a good tug. It should move no more than one inch in any direction (side to side or front to back).

7. Keep the instruction manual for the seat in the storage compartment located on the seat (almost all have them). Keep the car manual in your glove compartment so you can always find it.

8. Have a professional check your work, even if you’re pretty sure you did it right