Sunscreen 101: What protects what? UVA ingredients, UVB ingredients, broad spectrum! What you need to know! zArchived 4/18/08April 18, 2008 Protecting yourself from the sun is essential. With as much research out, it is no longer an optional step in your beauty routine. Most of understand that anti-aging creams are not nearly as effective as taking preventative steps that reduce aging rather than attempting to reverse what has already occurred.UVA & UVB? UVA damage occurs in shortwave (320 to 340nm) and long-wave (340 to 400nm), while UVB occurs between 280 to 320 nm. UVA tends to penetrate into the skin, while UVB damages the top layer of skin.Common Ingredients for UVA Protection: Avobenzone, Ecamsule (Mexoryl SX), Zinc Oxide; Titanium gives some, but not the entire range of the spectrumCommon Ingredients for UVB Protection: Octyl methoxycinnamate, octyl salicylate, octocryleneIngredient to watch for: Zinc Oixide provides protection against short and long UVA as well as UVB. Avobenzone protects against UVA, while oxybenzone only protects against short wave UVA and titanium dioxide protects up to 385nm (of 400nm).Caution: SPF is a measure of UVB protection, NOT UVA. In fact, many sunscreens labeled “broad spectrum UVA/UVB” do not protect against the entire UVA spectrum (short and long waves).Ingredients known for sun protection:Octocrylene is an organic compound used in sunscreens.Oxybenzone is a derivative of Benzophenone and an organic compound often used in sunscreens.Octisalate is a chemical suncreen ingredient that blocks UVB.Homosalate is an organic compound used in sunscreens to absorb ultraviolet rays.Avobenzone is an oil soluble ingredient that may also go by Parsol 1789, Eusolex 9020, Escalol 517.Octyl methoxycinnamate or octinoxate is an organic compound used for sun protection.Octyl salicylate is an organic compound used in sunscreens. It absorbs ultraviolet light.Dioxybenzone is an organic compound used to block UVB, derivative of benzophenone.Titanium Dioxide is used in sunscreen, and it is often used to because of its high refractive index.How effective is your SPF? Calculate how long you can stay in the sun with your sunscreen.