One of the main differences between SOLIUS and the sun is that the sun emits harmful UVA rays along with the UVB rays responsible for vitamin D production. SOLIUS has eliminated those UVA rays. One SOLIUS treatment is equivalent to, on average, 9 seconds in the midday sun in terms of the total amount of UVR exposure. SOLIUS is designed to minimize UV exposure as well as the potential for sunburn. However, if you have a history of skin cancer, consult your doctor to assess your suitability for SOLIUS.