Johann Ritter discovered ultraviolet light in 1801
While UV rays can be harmful to human health, some beneficial applications are
* Skin cancer is the most common form of cancer in the United States
* Ultraviolet (UV) radiation, from the sun and from tanning beds, is classified as a human carcinogen, according to the U.S. Department of Health and Human Services and the World Health Organization (http://www.epa.gov/sunwise/doc/uvradiation.html)
** Fluorescent bulbs typically use 65%-75% less energy than a standard incandescent bulb
source NASA graphic
A number of substances are able to absorb the energy in UV light and immediately convert it into visible light. This effect is called fluorescence. The ink in highlighter pens contains a fluorescent dye that enables the ink to reflect vividly in sunlight and to glow strongly in the dark when a UV lamp is shone on it.
We can use UV and fluorescence to make efficient lighting for offices, workshops and our own homes.
A UV toothbrush sterilizer
A UV sterilizer utilizes a germicidal fluorescent lamp that produces light at a wavelength of approximately 254 nanometers. As the light penetrates the bacteria, it mutates the DNA (genetic material), preventing growth/multiplication of the organism.
Some of the common dangers of UV rays on human health, specially due to time spent outdoors
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