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  2. Health effects of sunlight exposure - Wikipedia

    en.wikipedia.org/wiki/Health_effects_of_sunlight...

    On the positive side, UV exposure enables the synthesis of vitamin D 3, which is essential for bone health [1] and potentially plays a role in inhibiting certain cancers. [ 2 ] [ 3 ] While vitamin D can also be obtained through dietary supplements, [ 4 ] UV exposure offers benefits such as enhanced subdermal nitric oxide production and improved ...

  3. Fluorescent lamps and health - Wikipedia

    en.wikipedia.org/wiki/Fluorescent_lamps_and_health

    An open (single envelope) CFL [12] An encapsulated/closed (double envelope) CFL. Some fluorescent lamps emit ultraviolet radiation. [citation needed] The Health Protection Agency of the United Kingdom has conducted research concluding that exposure to open (single envelope) compact fluorescent lamps (CFLs) for over 1 hour per day at a distance of less than 30 cm can exceed guideline levels as ...

  4. Biological effects of high-energy visible light - Wikipedia

    en.wikipedia.org/wiki/Biological_effects_of_high...

    Blue light, a type of high-energy light, is part of the visible light spectrum. High-energy visible light (HEV light) is short-wave light in the violet/blue band from 400 to 450 nm in the visible spectrum, which in artificial narrowband form has a number of proven negative biological effects, namely on circadian rhythm and retinal health (blue-light hazard), which can lead to age-related ...

  5. Ultraviolet - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet

    UV radiation is often used to excite a given sample where the fluorescent emission is measured with a spectrofluorometer. In biological research, UV radiation is used for quantification of nucleic acids or proteins. In environmental chemistry, UV radiation could also be used to detect Contaminants of emerging concern in water samples. [108]

  6. Photokeratitis - Wikipedia

    en.wikipedia.org/wiki/Photokeratitis

    Photokeratitis or ultraviolet keratitis is a painful eye condition caused by exposure of insufficiently protected eyes to the ultraviolet (UV) rays from either natural (e.g. intense direct or reflected sunlight) or artificial (e.g. the electric arc during welding) sources. Photokeratitis is akin to a sunburn of the cornea and conjunctiva.

  7. Sungazing - Wikipedia

    en.wikipedia.org/wiki/Sungazing

    Sungazing is the unsafe practice of looking directly at the Sun.It is sometimes done as part of a spiritual or religious practice, most often near dawn or dusk. [1] The human eye is very sensitive, and exposure to direct sunlight can lead to solar retinopathy, pterygium, [2] cataracts, [3] and potentially blindness.

  8. Optical radiation - Wikipedia

    en.wikipedia.org/wiki/Optical_radiation

    Exposure to optical radiation can result in negative health effects. All wavelengths across this range of the spectrum, from UV to IR, can produce thermal injury to the surface layers of the skin, including the eye. When it comes from natural sources, this sort of thermal injury might be called a sunburn.

  9. Ultraviolet index - Wikipedia

    en.wikipedia.org/wiki/Ultraviolet_index

    A UV index reading of 8 to 10 means very high risk of harm from unprotected sun exposure. Take extra precautions because unprotected skin and eyes will be damaged and can burn quickly. Minimize sun exposure between 10 a.m. and 4 p.m. If outdoors, seek shade and wear sun-protective clothing, a wide-brimmed hat, and UV-blocking sunglasses.