SPF, which stands for Sun Protection Factor, has been used for decades to determine the level of protection someone can expect from the sunscreen they use. It can often vary from person to person given multiple factors such as testing methods and environmental factors. In addition, everyone’s skin is different, which can also affect what kind of SPF is best suited to fit their individual needs.
A common misperception is that the SPF number on a bottle signifies the amount of time you can spend in the sun without getting burned (30 minutes for SPF 30, 50 minutes for SPF 50 etc.) This is not accurate. In fact, the SPF rating system is far more complex and based on the degree to which a certain formula protects against the sun’s harmful UVB rays over a certain period of time. For example, a sunscreen with a rating of SPF 30 allows only 3 photons per 100 to penetrate the skin, meaning it shields approximately 97% of the sun’s harmful UVB rays. This roughly translates to 30 times the protection you’d have versus using no sunscreen at all. This extends to SPF 50 (98% or 50 times the protection) and SPF 70 (98.5% or 70 times the protection). The length of time that a sunscreen will protect you from sunburn will vary based on the UV index at the time as well as other factors.
At Sun Bum, we like to think we make sun care products for everyone. So, whether your SPF preference is 30 or 50, mineral or non-mineral, lotion or spray, you can stay protected from the sun’s harmful rays. As noted by the Skin Cancer Foundation, “The best sunscreen is the one you’ll use.”