Walk into any chemist or supermarket and you'll find shelves full of sunscreens all carrying the same label: SPF50+. But what does that number actually mean? And does it tell you everything you need to know about what you're applying to your family's skin?
For parents, particularly those navigating sensitive skin, understanding the label is a reasonable starting point for making a confident choice.
What SPF measures
SPF stands for Sun Protection Factor. It measures how much UV radiation (specifically UVB radiation, the kind responsible for sunburn) is required to cause redness on protected skin compared to unprotected skin.
SPF50+ filters approximately 98% of UVB radiation. SPF30 filters around 97%. That gap sounds small, but in Australian conditions, where UV levels are among the highest in the world, it’s a meaningful difference, particularly for babies, children, and anyone with fair or reactive skin.
What the “+” actually means
In Australia, the “+” in SPF50+ has a specific regulatory meaning: it isn’t just a marketing addition.
Under AS/NZS 2604:2012, the Australian and New Zealand standard for sunscreen labelling, a product can only carry the SPF50+ label if its independently tested SPF is 60 or above. A product that tests at 59 cannot legally be labelled SPF50+. The “+” signals that the actual protection level exceeds what the label shows.
This standard is one of the more rigorous in the world, and it’s worth knowing it exists, because not all sunscreen markets operate the same way.
Why independent testing matters
In recent years, a wave of Australian sunscreen recalls and independent consumer testing has highlighted a gap that many parents weren’t aware of: some sunscreens marketed as SPF50+ have been found to deliver significantly lower protection than their labels claim.
Australian sunscreen recalls are a reminder that labelling alone doesn’t guarantee performance. The more meaningful question is whether a product has been independently tested as a finished, shelf-ready product by an accredited laboratory, not just formulated and self-assessed.
For primary sunscreens (those regulated as therapeutic goods by the TGA), independent testing is a mandatory part of the registration process. Understanding which regulatory category a sunscreen falls into is a reasonable thing to know when you’re choosing one for your family.
UVB vs UVA: why broad spectrum matters
SPF only measures UVB protection. But UV radiation includes UVA rays too: rays that penetrate the skin more deeply and contribute to long-term skin damage.
A sunscreen labelled SPF50+ in Australia must separately satisfy broad spectrum requirements, demonstrating meaningful UVA protection alongside its UVB rating. Both criteria must be met before the SPF50+ label is permitted. When you see “broad spectrum SPF50+” on an Australian product, it means the product has cleared both standards, not just one.
A higher SPF doesn’t mean less frequent reapplication
This is one of the most common misunderstandings about sunscreen: and one worth clearing up.
SPF measures the level of protection, not how long a single application lasts. Sunscreen breaks down with UV exposure, sweat, and water contact regardless of SPF rating. The guidance is consistent: reapply every 2 hours, and after swimming or towelling dry.
Applying generously and reapplying regularly will always outperform a single application of a higher SPF.
How SPF is tested
For TGA-registered sunscreens in Australia, SPF testing is conducted on human volunteers under controlled laboratory conditions, using a UV light source calibrated to replicate natural sunlight. The test measures the minimum UV dose needed to cause visible redness on both protected and unprotected skin, and the ratio between the two determines the SPF value.
This method, ISO 24444:2010, requires an accredited, independent laboratory. It cannot be self-certified by the manufacturer. That independence is what makes it meaningful.
Lullaby SPF50+ Sensitive Skin Sunscreen is independently tested by Eurofins Dermatest, returning a mean SPF result of 61.0. It is registered on the Australian Register of Therapeutic Goods (ARTG: 391791). You can read the full detail of our testing here: Our SPF Standard
Using sunscreen effectively
The protection a sunscreen delivers depends significantly on how it’s applied. A few practical guidelines:
Apply generously to all exposed areas 15–20 minutes before going outside. Most people apply less than the tested amount, which reduces real-world protection.
Reapply every 2 hours, and after swimming or towelling dry.
Use sunscreen alongside protective clothing, hats, and shade, particularly during peak UV hours between 10am and 2pm.
For babies and children with sensitive skin, a small patch test before first full use is always a sensible step.
Understanding what sits behind the SPF50+ label makes it easier to choose sunscreen with confidence, not just familiarity. If you’d like to see exactly how our sunscreen is tested and what the results show, our SPF Standard page has the full detail.
