The number on a sunscreen only holds if you use as much as the lab did. Almost nobody does. The gap between how sunscreen is tested and how it is worn is one of the quietest problems in sun protection, and it is the reason SOLA comes one dose at a time.
How SPF is tested
Sun protection factor is measured with 2 mg of sunscreen on every square centimetre of skin. The European Commission puts that at about six teaspoons, roughly 36 grams, for the body of an average adult, and notes that this is more than most people apply.
Why using less matters so much
Protection does not fall in step with the amount. In the Commission’s words, if the quantity applied is reduced by half, protection may fall by as much as two-thirds. A thin, hurried layer can leave you with a fraction of the protection printed on the label.
What the SPF number really means
SPF is not a straight line. SPF 15 absorbs about 93% of UVB radiation and SPF 30 about 97%. Above SPF 50, the Commission notes, protection does not substantially increase. Applying enough, and applying it again, matters far more than chasing a higher number.
No sunscreen blocks all UV radiation, which is why European guidance warns against words like “sunblock” or “total protection”. Good protection also has to cover UVA as well as UVB, and in Europe the UVA protection should be at least a third of the SPF.
Apply it again
Sunscreen wears off. Reapply often to keep your protection, and always after swimming, sweating or towelling off. Spend less time in the midday sun, and keep babies and young children out of direct sunlight altogether.
One dose at a time
A bottle leaves the amount to guesswork. SOLA seals a single dose for the face and neck in each capsule, so every application starts from the same measured amount. You twist it open, warm it between your fingertips and smooth it on, and when you reapply you simply open another.
See the ritual, or read why Europe and the US make sunscreen differently.
Sources
Be first.
SOLA launches across the European Union in late spring 2027, and in the United States in 2027. The first two hundred people on the list become founding members.
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