Very recently the Federal Drug Administration (FDA) and the U.S. government changed their guidelines for the use of sunscreen products. If the product does not protect the user from both Ultraviolet A (UVA) and Ultraviolet B (UVB) radiation, the label cannot state that the sunscreen protects against skin cancer or premature aging of the skin.
The sun protection factor (SPF) on sunscreens with SPF above 50 will no longer be allowed to be stated on labels. The most a label can state will be an SPF of 50+, as evidence shows no demonstrably improved protection above 50 SPF.
In order to be considered a broad spectrum sun protectant, a product has to provide both UVA and UVB protection. At present, UVB protection has been labeled on most sunscreen or sunblock products. However, UVB rays can cause cancer, aging of the skin and sun damage.
UVB rays can be blocked by the windows in your home, the windshield on your car, as they cannot penetrate as deeply as UVA rays. These UVA rays do penetrate and do cause skin damage. Both types of sun rays can cause cancer, therefore the FDA has determined that the sunscreen products must protect against both.
No product will be able to promote itself as being waterproof or as a sunblock, as no product can completely block out the sun's rays. Nor is any sun protectant able to completely be waterproof. Sunscreen must be applied even after swimming, as it does come off and will no longer be effective.
The newer guidelines are meant to help consumers avoid confusion about which sun care products will actually protect them from cancer and premature aging of the skin. A sun product that provides broad spectrum protection against both UVA and UVB rays with an SPF of 15 or higher can be labeled to state that it will protect against cancer and premature skin aging. If a sunscreen is not broad spectrum protective, such as only protecting against either UVA OR UVB rays, it cannot state that it will help avoid cancer or skin aging.
Products can no longer be labeled to be sunblocks, nor waterproof or sweat proof. The closest to these labels are the words "water resistant" and it must state for how long, in minutes, the product will resist water before having to be reapplied.