What are UVA and UVB rays ?
UV (ultraviolet) rays are a form of electromagnetic radiation which comes from the sun in the form UVA and UVB rays.
UVA rays emit the least amount of energy of the three types of UV rays, causing the skin to age and potentially leading to some skin damage.
UVB rays emit more energy than UVA rays, and can cause direct damage to DNA in the skin cells, resulting in sunburn. UVB rays are responsible for the majority of cases of skin cancer.
When buying a suncream, you want to make sure that you purchase a broad-spectrum product that protects you from UVA and UVB rays.
What is SPF (Sun Protection Factor) ?
SPF measures the amount of protection a suncream can provide you against the sun's UVB rays. It is rated on a scale from two to 50+. The higher the SPF number, the stronger the protection you'll have. SPF provides you with an insight into how much longer it will take for your skin to turn red in response to UVB rays in comparison to if you weren't using any protection at all. Therefore, if you would normally start burning within 30 minutes without sun protection, then a suncream with SPF 30 would theoretically provide you with 30 times more protection, which equates to 15 hours of protection. However, this relative measure does not mean that you should go 15 hours without reapplying suncream, as suncream can come off by being dried by the sun or coming into contact with water.
Sun-screen Shelf Life
The majority of suncreams have a shelf life of between two and three years. So, if you're packing for a holiday and discover a dusty bottle of suncream at the back of your bathroom cupboard, it would be a wise course of action to swap it for a new one.
We recommend using sunscreens that include these ingredients : Zinc, Zinc
Oxide, Titanium Oxide.
The safest environmentally-friendly solution is to swim / snorkel / surf using a lycra UV shirt. Otherwise, ensure your sun-screen does NOT contain any of the following ingredients : Oxybenzone; Octinoxate; Avobenzone; Ethylhexyl Methoxycinnamate, Titanium Dioxide, Homosalate, Octisalate & Octocrylene.
Avoid sun-screens with high content of Titanium Dioxide. This mineral does not biodegrade and is found to react in warm seawater to form hydrogen peroxide which is harmful to all sea life. Oxybenzone and octinoxate, the two chemicals recently banned in Hawaii and are believed to cause coral bleaching.