UV Radiation be careful!
Sunscreen reflects and blocks UV radiation. The SPF is an index indicating the time a person can be exposed to the sun without burning.
For example, if your skin takes about 20 minutes to react to the sun without sun protection, you should use a sunscreen of SPF 15, since in theory protects you 15 times more, about five (5) hours.
Another way to look at is the amount of sunscreen it offers. If the SPF is 15 then the filter is 93%, 30 SPF filters 97%, 30 SPF filter 98%. After 50 SPF the increase is insignificant, for example, 70 SPF filters 98.6%. That’s why after 50 there is no scientific evidence that the protection is greater. There is not much difference between the protections of an SPF 50 to SPF 100.
I recommend to my clients to use a sunscreen SPF of not less than 30 SPF and apply it whenever you wash your face; is very important to find a good sunscreen that is made for your skin type, for example, oily skin or skin that is prone to acne cannot use any type of sunscreen.
We should use sunscreen on sunny days and cloudy days as well since we always have ultraviolet radiation exposure these rays are so powerful that we are able to notice the negative effects on our skin when we take walk outdoors just for a few minutes. We should also use sunscreen indoors like in our office and home, computers and light bulbs produce so much light that it’s able to emit ultraviolet radiation.