Deep heat

Sun rays can burn even through thick glass, and under water. Up to 35 percent of UVB rays and 85 percent of UVA rays penetrate thick glass, while 50 percent of UVB rays and 77 percent of UVA rays penetrate a metre of water and wet cotton clothing.

Take action: Apply sunscreen while driving your car on holiday, and water resistant block if you’re swimming. Stay indoors or in the shade between 10 am and 3 pm. Put on sunscreen if you’re going to be outside for more that 20 minutes.