Are you confident that your child's car seat is installed and used correctly?

Are you really?

Just in case, there's a free inspection going on somewhere in New Jersey practically every day.

According to the National Highway Traffic Safety Administration, nearly two-thirds of car seats in the U.S. are not installed correctly. That estimate, according to Safe Kids New Jersey, is a conservative one. Up to 75 percent of installed car seats could use some tweaking, the group says.

"There are a lot of common mistakes," said Carol Ann Giardelli, director of Safe Kids New Jersey, which is led by the Central Jersey Family Health Consortium. "Some of them can be detrimental to the safety of the child, but some are an easy fix."

Car seat no-nos

The most common mistake seen by experts and certified technicians is a car seat that's too loose, Giardelli said. If a car seat has too much give, it won't provide the right amount of restraint in the event of a crash.

To ensure a car seat is secured adequately, give it a shake at the base. If it can move more than one inch side to side or front to back, it can be tighter.

While it may provide peace of mind for you, the parent, to secure a mirror to the back-seat headrest, any accessories beyond the car seat itself should not be used, Giardelli said. That includes toys that can be tied on to the handle of the car seat.

"If it's not part of the car seat, it is not tested to withstand the force of a crash," Giardelli said. "They can become dislodged and become flying missiles."

Anything loose in the car, actually, is a threat to a young child during an accident — secure your umbrellas and even tissue boxes.

Installation of the car seat is half the battle. If your child isn't secure in the seat, a crash could do more harm than necessary.

The chest clip should be placed at armpit level, Giardelli said. And the straps should be tight against the child's body. A "pinch test," Giardelli said, will give you a good reading.

"If you try to pinch the webbing by the child's shoulder and are able to grab a pinch, they're not tight enough," she said.

It's a general recommendation that children not wear big winter coats while in a car seat. The bulkiness of the coat increases the chances that the harness is too loose.

The law

In New Jersey, it's the law that any child under 8 years old and a height of 57 inches be secured in the rear seat of a vehicle as follows:

New Jersey Division of Highway Traffic Safety

If a vehicle has no rear seats, a child may be secured as described above in the front seat. Children in a rear-facing seat may not be placed in the front of a vehicle if there's an active passenger-side airbag.

Safe Kids Worldwide suggests parents follow even stricter guidelines when graduating their child from level to level. Look at the label on the seat, Giardelli said, and keep your child in that seat until they reach the upper limits of the weight and height as required by the manufacturer.

NJ is here to help

"The car seat inspection stations in New Jersey are a tremendous resource," Giardelli said. "Even if you think you have your car seat installed correctly, it's worth a check to make sure."

All 21 counties have certified child passenger car seat technicians available to inspect a seat, free of charge.

Technicians prefer you arrive with the seat already installed, and not ask them to do all the work.

Look here for the statewide seat check schedule.

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Contact reporter Dino Flammia at dino.flammia@townsquaremedia.com.