What is SPF? what do the different SPf numbers actually mean? Which SPF should you choose?What is SPF & what does the number mean?I’m SPF or Sun Protection Factor is a measure of the protection your sunscreen offers against UVB rays, it gives an estimation of how much longer your skin would take to redden when using sunscreen compared to normal. So a sunscreen with SPF 30 would give a factor of 30x longer in the sun. If you normally burn in 10 minutes... BARE SKIN → 10 minutes SPF 15 → 150 minutes SPF 30 → 300 minutes This is not a true estimation, it will depend on the sun intensity, your skin type and how well you have put your sunscreen on! The Sun Protection Factor tells you about the effectiveness of your sunscreen at blocking UVB rays which are responsible for most of the burning and cancer risk but only represents 5% of the UV we are exposed to. SPF 15 → 93% SPF 30 → 97% SPF 50 → 98% SPF 100 → 99% One of the easiest ways to think of this is how many photons out of 100 are being blocked, whilst the difference between SPF 15 and 30 is only 4% - if SPF 15 lets 7/100 photons through, SPF 30 would let 3/100 through - half the number of photons so double the protection factor. All sunscreens for sale in Europe have to be tested in a standardised way within a Lab to generate SPF values, in line with recommendations from the European Commission. Zinc oxide is an effective broad-spectrum UV blocker, protection from UVA, UVB and even UVC rays. High SPF isn't everything - we need broad SpectrumUsing sunscreen helps to protect us from Ultraviolet waves which are linked to burning, ageing and skin cancer. Ultraviolet Radiation is a type of energy produced by the sun and some artificial sources. UV rays are on the electromagnetic spectrum between visible light and x-rays; invisible to human eyes, they can be split into three categories based on their wavelength and energy levels. (Finally using that GCSE science knowledge!) The Sun Protection Factor only tells you about the effectiveness of your sunscreen at blocking UVB rays - responsible for most of the burning and cancer risk. UVA: Immediate Tanning. Skin Damage, Wrinkling, Ageing - Although the shortest wavelength UVA rays also cause sunburn and are linked to the formation of certain skin cancers. UVB: Delayed Tanning. Sunburn, Skin Cancers and a little premature ageing. UVC: Redness, serve burns, skin cancer & ageing. Filtered by the atmosphere For protection from both UVA and UVB rays, you should look for a sunscreen which offers ‘Broad Spectrum’ Coverage - meaning that it will help to protect from both UVA and UVB. The European Commission recommends that the UVA protection is at least ⅓ of the SPF and increases relative to the SPF value. You can look for the UVA symbol ("UVA" in a circle) on the packaging. Why higher spf isn't always betterNo sunscreen is 100% effective at blocking UV rays, so even if you use the highest SPF and reapply regularly you still need to reduce your exposure to the sun and think about UVA rays - sunscreen isn’t the solution to everything. Often people using very high SPF (50+) don't take other precautions or reapply their sunscreen during the day because they think it is so strong it will carry on being effective and are lulled into a false sense of security. It is important to remember to seek shade during the middle of the day when the sun is at its most intense; cover up with a hat and clothing; and apply sunscreen regularly in-line with the guidelines on the packet! Most people only use ½ to ¼ of the recommended amount of sunscreen. HOw should you apply sunscreen?If using a chemical sunscreen you should apply your sunscreen 30 minutes before going outside to make sure that it has time to absorb into your skin. If using a mineral sunscreen (like the ones on in our shop) you should apply 10-15 minutes before going out, the minerals work by creating a physical barrier so work instantly where you’ve applied it. With any sunscreen make sure that you apply generously and that you rub it in well. Remember to reapply your sunscreen every 2hrs and straight after towelling, swimming or sweating. HOw much sunscreen should you use?QUICK RECAP
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April 2021
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