How does sunscreen work?
A broad spectrum sunscreen works by screening both UVA and UVB radiation. There are 2 ways sunscreens can do this: • By chemically absorbing UV radiation and therefore preventing it from reaching your skin. • By physically blocking or reflecting UV radiation – these sunscreens contain zinc oxide or titanium dioxide which scatter the UV radiation away from your skin. Chemical absorber sunscreens are the most common. These are usually non-greasy and easy to apply. Broad spectrum sunscreens contain several chemicals that absorb UVR over the UV spectrum. What is SPF? SPF stands for Sun Protection Factor. This is a rating which indicates the relative strength of protection the sunscreen will provide against UV radiation. In Australia, sunscreens must achieve a rating of at least SPF 4, up to a maximum of 30+. Anything less than SPF 15 offers only low protection. How do I use sunscreen properly? • The best sunscreen to use is SPF 30+ broad spectrum, water-resistant sunscreen. • It’s a mistak
People tend to take their skin for granted and let it fry in the sun. Using gobs of sunscreen helps prevent the damage. But how exactly does it work? The aptly named “Howstuffworks” explains that sunscreen absorbs or blocks ultraviolet light, thanks to several “absorption chemicals” like para-aminobenzoic acid (PABA). You shouldn’t let the word “acid” scare you off, but it’s worth noting that PABA may cause irritation in folks with sensitive skin. The Library of Congress offers a more in-depth explanation. Essentially, sunscreen works “by combining organic and inorganic active ingredients.” Zinc oxide and titanium oxide are inorganic. They “reflect or scatter ultraviolet (UV) radiation.” Meanwhile, organic ingredients such as octyl methoxycinnamate and oxybenzone “absorb UV radiation” and dissipate it as heat. This may be verging on too much information, but ac
By combining organic and inorganic active ingredients. Sunscreen works by combining organic and inorganic active ingredients. Inorganic ingredients like zinc oxide or titanium oxide reflect or scatter ultraviolet (UV) radiation. Organic ingredients like octyl methoxycinnamate (OMC) or oxybenzone absorb UV radiation, dissipating it as heat. Some sunscreens protect us from the two types of damaging UV radiation: UV-A and UV-B. Both UV-A and UV-B cause sunburns and damaging effects such as skin cancer. Ultraviolet radiation is broken into three types of wavelengths: UV-A: This is the longest wavelength and is not absorbed by the ozone. It penetrates the skin deeper than UV-B. UV-B: Responsible for sunburns. It is partially blocked by the ozone layer. UV-C: This is totally absorbed by the earth’s atmosphere; we encounter it only from artificial radiation sources. When purchasing sunscreen, the Sun Protection Factor or SPF measures how effectively the sunscreen formula limits skin exposure
