UVB rays only affect the outer layers of skin, and are what spark the production of melanin. They are responsible for causing burning, freckling and skin cancer.

How does sun cream work?

Sun cream works by absorbing UV rays in the same way as melanin. Different chemicals are used to absorb UVA and UVB rays.

The Sun Protection Factor (SPF) level marked on the bottle indicates how many times more protection the lotion will give you than your skin’s natural defences – against UVB rays only.

For example, the protection against sunburn that your skin would offer you for ten minutes can be extended for 150 minutes by applying factor 15 sun cream.

What is sun burn?

Sunburn is the skin’s reaction to the damage caused to your cells by the sun’s UV radiation. More blood cells are sent to the affected area to repair the damage, which causes the skin to turn red.

What is sunstroke?

Sunstroke, also called hyperthermia, is the state the body goes into when it is unable to cool itself down and prevent itself from overheating.

It can set in very suddenly, and symptoms include headaches, dizziness, hot and dry skin, raised pulse and slow reactions. Patients should be cooled down quickly, but attempting to do this too fast with ice or cold water could send them into thermal shock, which can be fatal.

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