PORTLAND, Maine — It's one of the first things new parents do when they leave the hospital for the first time: they fasten their newborn into a safety seat. It can be a white-knuckle inducing experience but it's something parents will have to do or think about daily from that day forward, for years.

As children grow, their safety seats change. And as vehicles evolve so do safety standards for child safety seats.

Late last week, Governor Janet Mills signed new child safety seat rules into law, the first changes in about a decade. Proposed as LD 1269, An Act To Update Laws Governing Child Safety, the new rules define the required time a child needs to remain in a rear-facing seat and changes the weight requirement for forward-facing seats used with a harness.

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"It's going to make a significant impact on the lives of kids," said Sgt. Lance Mitchell, a police officer, and child passenger safety instructor.

"Most parents want to do the best they can for their kids," said Corey Perreault, a child passenger safety instructor for more than 20 years. "Most crashes are frontal crashes so everything that's crash tested is designed in that way. So when you're rear-facing you're cradled."

Maine joins states like Connecticut, Rhode Island, and New York in requiring children to remain in a rear-facing safety seat until the age of two.

For children older than two they now must be secured in a forward-facing seat with a harness until they weigh 55 lbs. Before the new law, that weight was set at 40 lbs. 

Those who violate the new rules could face up to $250 in fines.

The legislation received the governor's signature June 14. It will take effect 90 days following adjournment of the 129th Legislature. 

Perreault says the most common mistake she sees parents make when it comes to installing car safety seats, is that they are secured too loose. To help parents with that, there are free safety checks happening statewide -- including one in Bangor this Saturday.

It's happening June 22 between 10 a.m.nd 1 p.m. at Quirk Chevrolet at 293 Hogan Road. Making an appointment ahead of time is recommended.