Ultraviolet radiation Indoor tanning

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typical f71t12 71-inch, 100-watt, bi-pin tanning lamp


ultraviolet radiation (uvr) part of electromagnetic spectrum, beyond visible light. ultraviolet wavelengths 100 400 nanometres (nm, billionths of metre) , divided 3 bands: a, b , c. uva wavelengths longest, 315 400 nm; uvb 280 315 nm, , uvc wavelengths shortest, 100 280 nm.


about 95% of uvr reaches earth sun uva , 5% uvb; no appreciable uvc reaches earth. while tanning systems before 1970s produced uvc, modern tanning devices produce no uvc, small amount of uvb , uva. classified group 1 carcinogen, uvr has complex , mixed effects on human health . triggers synthesis of vitamin d , endorphins in skin, causes skin cancer , other damage, including wrinkles.





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