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Radian® Safety Hub

Radian® Safety Hub

Welcome to the Radian® Safety Hub! 

Here you'll find all of our handy safety tips and tricks from our team of expert CPST's. Use these videos alongside your car seat and vehicle manual to ensure a secure ride from day one.

For the Diono Booster Safety Hub, click here

For more FAQ's, visit Diono's FAQ hub here

The Diono Radian® is the original 3-across all-in-one car seat. We're often asked, "will a Radian fit 3-across in my vehicle?" Our CPST, Scott, explains how to find out.

"Truth is, it’s not always an easy yes or no answer; a lot of it depends on the actual physical space in your car. Diono car seats are 17 inches wide so you need a bare minimum of 51 inches of space from one side to the other in your back seat. The other thing you have to think about it actual seat shape and seat contour, if there’s a big hump in the center, and where your seatbelts are located. Sometimes in a situation like this where the seat belts are right next to each other, a car seat might actually sit on one or both of the seat belt buckles. In this scenario, you might have to fudge the seats and move them a little bit to get them to install correctly. I always recommend installing the center seat first to see if you can get a good installation there and then move to the outboard positions to see if you get good installations. If that’s true and you can get a solid installation in all three seating positions, then 3-across will work for you."

Your car seat manual is one of the most valuable pieces of information you can find.

Watch this video to learn where the manual is located in your Radian® R Series and Radian® Q Series. On the back of your Radian® Q seat you’ll see a book icon that indicates the manual is stored inside that door. Simply flip it up and you’ll find the manual. On the Radian® R seat you’ll find the same icon on the child’s left side of the seat, that means the manual can be found underneath the cover. Simply undo the cover and pull out the envelope containing the manual. Just in case you’ve lost or misplaced your manual, you can find all of our manuals for new and older models at

In this video Scott explains the proper harness strap location for a rear-facing child. When rear-facing you’ll always want the harness straps at or below the shoulders, meaning they’ll come up and over the shoulder rather than from above. This is because when a child is rear-facing in a frontal collision they’re going to slide up and forward in their car seat, and harness straps coming in from below the shoulders limits how much they move in the seat. Remember, rear-facing is always at or below the shoulders.

Follow the links below to find even more of our detailed video explanations to some of our most frequently asked questions that support your Radian® Installation, securing your child in Radian® or find answers to questions that you wish you could ask a car seat expert!

Will Radian fit 3-across in my vehicle?

Our most common question asked is “will I be able to fit Radian 3-across in my vehicle?”. Here’s how to tell!

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The importance of child passenger safety

We’ve been passionate about child passenger safety since 1999. But what’s the big deal? We asked our CPST, Scott, why child passenger safety is so important.

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Harness Straps: How to Use Properly and Why They Are So Important

Harness straps play a crucial role in your child’s safety, but it can feel tricky to get them just right. Let’s take a look at how to fit them properly, as our CPST explains why they’re so important.

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Car Seat Fit Guide: All-in-one car seats

Ready for the road? Make sure to check for these common car seat fitting mistakes and learn these top tips for safe travels.

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Get a Safely Installed Car Seat with this CPST 5-Point Check

Okay, you’ve read your vehicle and car seat manuals and you’re pretty sure that your car seat is installed correctly, but you want to be extra sure before you hit the road. Good news, there’s a CPST Approved Checklist for that!

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Keeping your Diono car seat clean and looking its best

6 ways to clean your car seat covers and keep your Diono car seat clean.

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