Usually refers to the safer, long-wave UV-A (350-400 nm) portion
of the spectrum and should not include the more dangerous short-
wave UV-B light (250-275 nm); both types can be responsible for
yellowing of artificial nail coatings. When all the wavelengths
of the visible light spectrum strike your eye at the same time,
white is perceived. That is why visible light is sometimes
referred to as white light. Technically speaking, white is not a
color at all, but rather the combination of all the colors of
the visible light spectrum. Ultraviolet light is a form of
radiation that is not visible to the human eye. It’s in an
invisible part of the “electromagnetic spectrum.” Though some
ultraviolet waves from the sun penetrate Earth’s atmosphere,
most of them are blocked from entering by various gases like
ozone. February 19, 2013 UV nail lamps do not appear to
significantly increase the lifetime risk of keratinocyte
carcinoma — a type of non-melanoma skin cancer — in consumers,
reports a study published in the Journa