Q. How long is the Marriage License valid?A. A Marriage License is valid for 60 days, beginning the day after it is issued. Members of the armed forces who can prove they are on active duty at the time of applying for the Marriage License can obtain a Marriage License valid for 180 days.
Lesson Summary. UV light is one type of electromagnetic wave. Other electromagnetic waves include radio waves, microwaves, visible light, and X-rays. UV light is used by humans to produce vitamin D, but overexposure to UV light can damage DNA and cause painful sunburns, cataracts, and skin cancer.
UV Radiation. Ultraviolet (UV) radiation is defined as that portion of the electromagnetic spectrum between X-rays and visible light or between 40 and 400 nanometer (nm) wavelengths. The primary source of UV radiation is the sun. There are also a number of artificial sources, such as tanning booths and halogen lights.