What Does the “SPF” Number Really Mean?

With summer in full swing and ski season fast approaching, you’ll still find piles of sunscreen available at most pharmacies and grocery stores. Experts have been talking about the danger of sun exposure for decades now, and there certainly is an abundance of sun protection products on the market, all claiming to give you the sun protection you need. While you may know that SPF stands for Sun Protection Factor, what does the SPF number really mean? Does SPF 100 really protect you better than SPF 30?

Here’s how it works. SPF’s are determined by testing artificial UV (ultra violet) radiation in a laboratory. Volunteers come to the lab and have their skin exposed to artificial sunlight to see how long it takes for their skin to burn. Then, sunscreen is applied to the volunteer’s skin and he/she is again exposed to artificial UV radiation.

The SPF is determined by dividing the amount of radiation required to burn with sunscreen by the amount required to burn without sunscreen. So the SPF number really is a standard for how long you can tolerate sun without burning. If you can withstand sun exposure for ten minutes without burning, then an SPF of 30 would allow you to spend 300 minutes in the sun before burning. An SPF of 15 would allow you to be able to withstand sun exposure for 150 minutes before burning.

Your sunscreen should protect your skin from dangerous UV rays, but it should also be safe. Take a look at our Pharmaca’s entire line of natural sunscreen products and rest assured that we offer the safest, most effective sunscreens on the market.

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