About a day later, the six spots are examined for redness. Afterward, each of those areas is exposed to five or six intensities of ultraviolet light from a sun simulator for a set time based on how quickly the panelist’s skin burns without protection. Then they soak in a tub of water for 40 or 80 minutes, depending on the product’s water-resistance claims. To check for SPF, a standard amount of each sunscreen is applied to a 2x3-inch rectangle on our panelists’ backs. Our SPF test is similar to the one the FDA requires, but we use fewer panelists. In addition to rating each sunscreen for SPF, we test for UVA protection and also list CR’s average tested SPF.Īlas, there are no trips to Tahiti for our sunscreen panelists-they go to a lab. (The American Academy of Dermatology recommends using a product with an SPF of 30 or higher.) We buy the sunscreens for our tests off the shelf, the way consumers would, and use three samples, preferably with different lot numbers, of each product. We test only sunscreens with a listed SPF of at least 30 that are water-resistant for 40 or 80 minutes, the two time periods for which the FDA permits water-resistance claims. Here’s what you need to know about Consumer Reports’ sunscreen testing, and how to find a product that works best for you and your family.ĬR uses a testing protocol that is modeled on the one the Food and Drug Administration requires sunscreen manufacturers to use. But as is the case with other products we test that have government or industry standards, we use those standards as benchmarks and develop our own methodology to identify differences in performance and give consumers a comparative evaluation. ![]() That’s why you need to look for a broad-spectrum sunscreen, which protects against both UVA and UVB. to 4 p.m., UVA rays are present as long as there is daylight. Unlike UVB rays, which are strongest from 10 a.m. These are the rays that tan and age skin, and along with UVB, contribute to skin cancer. UVA rays penetrate the skin more deeply than UVB. SPF also doesn’t tell you anything about how well the sunscreen protects against UVA rays. ![]() The breakdown: SPF 30 blocks 97 percent of UVB rays, SPF 50 blocks 98 percent, and SPF 100 blocks 99 percent. And no sunscreen blocks 100 percent of the sun’s rays. In addition, the intensity and wavelength distribution of UVB rays vary throughout the day and by location. So you need to reapply every 2 hours, or immediately after swimming or sweating. For example, if you’d normally burn after 20 minutes in the sun without sunscreen, an SPF 30 theoretically protects for 600 minutes, or 10 hours. Once the sunscreen gets on your skin, however, it begins to break down and it can also be rubbed off. Usually the number is explained as the amount of time it takes an individual’s exposed skin to burn when it’s covered in sunscreen compared with when it’s not. ![]() The SPF number is a measure of how well a sunscreen protects against sunburn, which is mostly the result of exposure to the sun’s UVB rays. We also look at how closely the sun protection factor (SPF) listed on the product’s label matches a sunscreen’s average tested SPF. ![]() We test sunscreens to determine their effectiveness against the sun’s ultraviolet A and ultraviolet B rays. Still, ideally you want to use a product that you can count on to fully protect your skin. The second most important thing is that any sunscreen is better than none. Here’s the most important thing to know about sunscreen: Everyone 6 months and older, regardless of skin tone, should use it on exposed skin when they head outside (even on cloudy days).
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |