To determine the length of your SOLIUS treatment, you will be asked questions about your skin tone and sensitivity to sun exposure. Your answers to these questions will determine the length of treatment necessary to deliver an effective amount of light to your skin. For individuals with lighter skin, treatments will last on average 2-3 minutes and for individuals with darker skin, treatments will last on average 7-9 minutes. Treatment times increase for darker skin tones because people with more melanin in their skin require longer exposure times to stimulate vitamin D production. SOLIUS treatment lengths are determined using literature studies, phototest studies, skin type questions and individual skin response to make sure therapy is safe and effective for people of all skin tones