There are two types of products that protect the skin from the sun's damaging ultraviolet radiation: chemical and physical products.
Sun screen is classified as chemical, while sun block is physical (physical sun screen).
So to repeat, a sunblock is suppose to physically block the sun's UV radiation of the skin, both UVA and UVB.
To help understand the difference between UVA and UVB just think about the last letters:
- UVA: Is sometimes called the "Aging Ray"
- UVB: Is sometimes called the "Burning Ray"
Sunscreens actually absorb the ultraviolet B radiation, thus and reducing the amount of radiation that penetrates the skin that causes burning.
But while sunscreen lotions prevent burning they are less effective at blocking out UVA rays
THIS IS THE DANGER.
Because it is believed that UVA is what cause melanoma, the most dangerous skin cancer.
Chemical sun blocks scatter, reflect, and physically block UV radiation. The most well-known chemical sun block is zinc oxide.
is found in 90 per cent of sun screen brands.
