SPF is an abbreviation for "sun protection factor." A sunscreen's protection factor (SPF) is figured by comparing how long it takes sunscreen-protected skin to burn to the length of time it takes unprotected skin to burn. The higher the SPF, the more protection you get against UVB rays. SPF strengths range from 2 to 50 and higher, but dermatologists recommend that all skin types use a product with a minimum of SPF 30 that is water-resistant and broad-spectrum, meaning it deflects both UVA and UVB rays. While some sunscreens block both UVA and UVB rays, the SPF number only rates its ability to deflect UVB. Researchers are working on a system to rate UVA protection.
Use a sunscreen and wear protective clothing to safeguard your skin from the sun’s harmful rays.