Suncare Facts - Water & The Sun's Rays We often cool down in or near water - at water-parks, swimming in sea or pools, on boats or enjoying water-sports. Water can make skin feel cooler, often hiding the effects of the sun until later so it’s important to use a water-resistant sun lotion. Refraction from the water intensifies the UV rays. At half a metre depth UV is still 40% as intense as at the surface. Use a higher factor than normal - Natural Tone Organic Skincare’s SPF30 is perfect, offering maximum protection and, being naturally biodegradable, is reef-friendly. Re-apply your SPF30 after you exit the water. Remember some products may be water-resistant but they will come off when drying yourself with a towel.