Young Curly Brunette Girl Undresses A Black Bikini Bra In The Sand On A Sunny Day

• Ultraviolet C or (UVC) range, which spans a range of 100 to 280 nm. The term ultraviolet refers to the fact that the radiation is at higher frequency than violet light (and, hence also invisible to the human eye). Owing to absorption by the atmosphere very little reaches the Earth's surface (Lithosphere). This spectrum of radiation has germicidal properties, and is used in germicidal lamps.
• Ultraviolet B or (UVB) range spans 280 to 315 nm. It is also greatly absorbed by the atmosphere, and along with UVC is responsible for the photochemical reaction leading to the production of the ozone layer.
• Ultraviolet A or (UVA) spans 315 to 400 nm. It has been traditionally held as less damaging to DNA, and hence used in tanning and PUVA therapy for psoriasis.
• Visible range or light spans 380 to 780 nm. As the name suggests, it is this range that is visible to the naked eye.