Letters and prescriptions must be dated within one year of exemption request. Step 1: Schedule a 5-minute verification phone call with our physician.Window tint medical exemptions allow you to install darker tint on car windows. See all requirements for medical waivers, certificates and exceptions. How do I fill this out? The DMV gives medical authorizations to individuals seeking protection from the sun, so your local DMV may be a good starting point to obtain a form.