SPF Explained

SPF Explained


  • All sunscreens will display a number that is followed or preceded by the letters SPF (Sun Protection Factor). The SPF refers to the sunscreens potential to block UVB rays only. SPF numbers range from 2 to 50+.  The numbers tell you the time the skin will take to redden with the sunscreen versus the amount of time it will take to redden without the sunscreen.¹ 
  • It is important however to err on the side of caution, always remembering that various environmental and behavioural factors can affect this, and geographical location and time of day can alter your tolerance greatly.
  • Additionally, sun protection is also dependent on your own skin type. And above all, the sun protection is only given in full, if enough product is applied, and to all areas of your skin.
  • Recommended are 2 mg/cm2 for one application, which means, for example, about 1 to 2 finger lengths of sun cream for the face or 2-3 tablespoons of product for an average adult’s body.² This is more than you think!


  • UVB penetrates and damages the outermost layers of your skin. Overexposure causes suntan, sunburn and, in severe cases, blistering.
  • UVB is connected to the Sun Protection Factor (SPF) on labels of sunscreen products. 
  • UVB rays can be filtered and do not penetrate glass.
  • UVA rays cause tanning , and the shorter wavelengths of UVA also cause sunburn. There is no such thing as a safe or healthy tan. UVA radiation is proven to contribute to the development of skin cancer.
  • UVA is connected to the “broad-spectrum protection” you see on the labels of sunscreen products. 
  • UVA rays, while slightly less intense than UVB, penetrate your skin more deeply. Exposure causes genetic damage to cells on the innermost part of your top layer of skin, where most skin cancers occur. The skin tries to prevent further damage by darkening, resulting in a tan. Over time, UVA also leads to premature aging and skin cancer.
  • UVA can penetrate windows and cloud cover.


  • Mineral Sunscreen: Mineral sunscreen, which is often also referred to as physical sunscreen, stays on the surface of the skin and deflects the sun's harmful UV rays. The active ingredients in physical/mineral sunscreen are Zinc Oxide or Titanium Dioxide. These minerals contain small particles that sit on the skin to create a physical barrier. This barrier protects the skin and causes UVA & UVB rays to bounce off it. You often see mineral sunscreen referred to as sunblock, although you should know that no sunscreen can block out all the UV rays.  Mineral sunscreen offers immediate protection, is better for sensitive skin and the environment.
  • Chemical Sunscreen: Chemical sunscreen differs, as it’s absorbed into the skin and protects by inactivating the UV rays through a chemical reaction. It is important to note that it takes 15-30 minutes for these to be fully absorbed into the skin, to provide the full intended protection. With this in mind, you should make sure to apply them in due time before exposing your skin to the sun. Chemical sunscreen is more water and sweat resistant, is easier to apply and doesn't leave a white film on the skin.
  • Broad Spectrum: This means that there is protection against both UVA and UVB and therefore should be part of any sunscreen you apply.


  • Apply a broad spectrum sunscreen, with a factor suitable for your skin type and exposure, 30 minutes prior to being out in the sun, to all parts of the body.
  • Always wear a hat when out in the sun to protect your scalp from the suns harmful rays and to reduce the risk of heat stroke.
  • Apply an appropriate amount of sunscreen to all areas of skin exposed to the sun, not forgetting your hands, ears and back of neck, reapplying every two hours.
  • Make sunscreen part of your daily, year round skincare routine, remembering that UVA rays can penetrate both windows and cloud cover.
  • It is recommended to keep babies and toddlers completely out of the sun. 
  • Clothing is the most effective form of sun protection. Keep skin exposure to a minimum.

Spending time in the sun increases your risk of skin cancer and early skin aging.

Shop All Sunscreen 



  1. British Skin Foundation
  2. Nivea Advice
  3. Skin Cancer. Org
  4.  Mineral vs Chemical Sunscreen

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