Sun-safe swimwear for kids: what UPF 50+ actually means

I spend a lot of time thinking about what our kids’ swimwear looks like. Colours, prints, proportions, where a zip sits, how a rashie fits.

But there’s one part of swimwear design that matters more than all of that, and you can’t actually see it in a product photo.

How well does the fabric protect your child from the sun?

Because whilst our swimsuits and rashies are designed to look good, ultimately it’s how they work and hold up against the Australian sun that’s important.

And this is where UPF comes in.

What does UPF actually mean?

UPF stands for Ultraviolet Protection Factor. In simple terms, it tells you how effectively a fabric blocks ultraviolet radiation from the sun.

Think of it a little like SPF for clothing, although the two ratings are measured differently.

In Australia, sun-protective fabrics are rated as UPF 15, 30, 50 or 50+. UPF 50 and UPF 50+ are classed as providing excellent protection. A UPF 50 fabric blocks at least 98% of UV radiation.

That matters because ordinary fabric doesn’t automatically equal sun-protective fabric.

The weave or knit of a fabric, its construction, colour and other characteristics can all affect how much UV radiation gets through. You can’t really tell by looking at a swimsuit on a website.

Which is why testing matters.

So, what is ARPANSA?

ARPANSA is the Australian Radiation Protection and Nuclear Safety Agency, an Australian Government agency responsible for radiation protection.

Among other things, ARPANSA has a NATA-accredited laboratory that tests fabrics and clothing materials to determine their UPF rating.

Testing is carried out in accordance with the Australian standard for sun-protective clothing, AS 4399:2020.

Which sounds very technical, but the bit that matters as a parent is pretty simple.

If a fabric has been tested by ARPANSA and given a UPF rating, you’re not relying on a brand simply saying that the material offers sun protection. There is independent testing behind that claim.

ARPANSA can test a material and determine how much ultraviolet radiation it blocks, giving it a UPF rating based on the results.

That’s why we have our swim fabric tested rather than simply assuming it offers enough protection.

Maybe no one gets particularly excited about laboratory testing when they’re buying a kids’ swimsuit. I do.

What does ARPANSA testing actually tell you?

There’s an important distinction here.

ARPANSA testing verifies the UPF performance of the material that has actually been tested. It doesn’t automatically mean every product a brand makes has been tested, and ARPANSA doesn’t assess the overall design or body coverage of a garment as part of its material test report.

So when looking at sun-safe swimwear for kids, I’d look for a clear UPF rating and information about how that rating has been tested, rather than vague claims about a fabric being “protective”.

And coverage matters too.

It’s one of the reasons rash vests and swimsuits with more coverage make so much sense for kids who are going to spend hours running between the water, sand and whatever slightly questionable game they’ve invented on the beach.

Fabric can only protect the skin it actually covers.

It’s also worth remembering that things like stretching, getting wet and normal wear can affect how a material performs over time.

And you still need sunscreen

This one feels obvious, but UPF swimwear isn’t a replacement for sunscreen.

For the bits of skin that swimwear doesn’t cover, use a broad-spectrum, water-resistant SPF 50 or SPF 50+ sunscreen and reapply it regularly, particularly after swimming.

ARPANSA recommends reapplying sunscreen every two hours and after swimming or water sports.

And yes, applying sunscreen to small children remains one of those jobs that sounds much easier than it is.

Don’t forget the hat either

Clothing is only one part of sun protection.

A hat helps protect the areas swimwear obviously can’t cover. For maximum protection, Cancer Council and ARPANSA recommend styles that provide shade to the face, head, ears and neck, such as broad-brimmed, bucket and legionnaire-style hats.

Caps still provide shade to parts of the face and head, but they don’t offer the same coverage to the ears and neck, so those areas need particular attention with sunscreen and shade.

Add sunglasses where you can, find shade when it’s available and keep an eye on the UV index.

None of these things really work as a replacement for the others. They work together.

For us, function comes first

I love designing kids’ swimwear. I care about getting the brown exactly right. I care about the fit. I care about a rash vest neck opening being big enough that you don’t have to wrestle it off a wet three-year-old.

But none of those details mean much if the swimwear doesn’t do the job it was made to do.

Our swimsuits and rashies are made from sun-safe fabric, because sun protection and safety come first, ALWAYS!

The prints and colours are the fun bit. 

References

For anyone who wants to read further or double-check the technical side of UPF and sun protection, check out the ARPANSA website below:

Australian Radiation Protection and Nuclear Safety Agency (ARPANSA)