American SPF is Weak Sauce
Mathematically speaking, the SPF number on the bottle (in any country) is the multiple for how much longer you can last in the sun before turning medium rare. For example, if it takes you 10 minutes to burn without sunscreen, an SPF 15 would give you 150 minutes protection. Most countries don’t test SPF effectiveness in relation to water exposure, however, and that’s where the Australian Department of Health and Ageing goes the extra kilometer. They put sunscreen to the post-immersion test. After application, subjects are thrown into controlled turbulent water and left to roast. It’s only then that a sunscreen has its SPF label slapped on. That means equivalent American and Australian SPF numbers are actually vastly different—the Aussie SPF is battle-tested.
Big news (we hope you’re sitting down): Sunscreen and sunblock are two different things. Sunscreen is formulated with chemical components to absorb UV light. Sunblock contains particles that physically block UV rays. Most products on the market are a combination of the two. These are ideal because they offer ‘broad spectrum’ protection to guard you against both UVA rays (responsible for the signs of aging) and UVB rays (cause sunburn). Check the list of ingredients on your protection to make sure you know what you’re getting, because this can be about as confusing as a game of Australian knifey-spoony.
More is Less Burn
Your epidermis is showing, and there’s a lot of it. Regardless of the SPF number, you should never be stingy. Specialists recommend putting on a full shot glass of sunscreen in order to make sure that you are fully covered. Also, timing is crucial. Allow 30 minutes to let sunscreen settle into the skin before you hit the great outdoors. If you have an Australian brand like eshu handy, more power to you. We say put it to your own turbulent water test.