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UVA and UVB rays differ in their effect on the skin:

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UVA rays have a longer wavelength and penetrate deep into the skin. They are the main cause of long-term damage such as premature skin ageing and wrinkles.

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UVB rays have a shorter but stronger energy. They affect the upper layers of the skin, cause sunburn and increase the risk of skin cancer.

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Adequate UVA protection should be at least one third of the stated UVB protection (SPF). This means that if a sunscreen has an SPF of 30, for example, the UVA protection must be at least 10.

 

In the EU and Switzerland, this is a legal requirement and products that meet this standard often have a UVA symbol in a circle on the packaging. This symbol indicates that the UVA protection meets the minimum standard required to protect the skin from the harmful effects of UVA rays.

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