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.
