We all love to bask in the sun when we travel. It gives us warmth and that endorphin rush which then provides a subjective feeling of well-being wherever we go. We also love outdoor activities in the daylight, like jogging, swimming, biking, and hiking. That being said, most of us are almost always exposed to the sunlight, with some people being exposed more excessively. Not to worry though, there’s this thing called sunblock. But with all the available products in the market today with labels like SPF 15, 15+, 50, or 100… It all gets confusing doesn’t it? Here we shed some light, and not necessarily sunlight.
The SPF you see on sunblock bottles stands for Sun Protection Factor. It basically refers to the amount of time you can stay in the sun without getting sunburned. Like, for a sunblock lotion with SPF of 15, it would allow you to stay in the sun 15 times longer than you could without protection.
So, for example, if your skin starts to redden in 10 minutes without sun block, applying a product with SPF 15 increases that time by a factor of 15, meaning you could stay in the sun for 150 minutes or 2 and a half hours. This implies that you do need to re-apply your sunblock once in a while, depending on its sun protection factor.
In addition, a higher SPF blocks out more rays—a product with an SPF of 15 will filter out approximately 93 percent of UVB rays; SPF 30 filters out about 97 percent. However, some sunblocks only have UVB protection so do look for one that protects against both UVA and UVB.
But in reality, the facts stated here are not quite so straightforward. There are a variety of other factors that affect how well you are protected from the sun. Sunscreen can be easily washed off by exposure to water or sweat too, which can leave parts of your skin vulnerable to UV rays.
For all of this reason, it’s not a good idea to solely rely on SPF to gauge how much time you can spend in the sun. The right thing to do would be to wear protective clothing, re-apply sunblock once in a while, and choosing to do outdoor activities during the safe time which is before 10 a.m. and after 2 p.m.