Search results
Results From The WOW.Com Content Network
Most people in the world depend on the sun to get vitamin D, [31] and elderly populations in low UVB countries experience higher rates of cancer. [32] There are not many foods that naturally have vitamin D. [33] Examples are cod liver oil and oily fish. If people cannot get sunlight, then they will need 1,000 IU of vitamin D per day to stay ...
In 2009, Natural Resources Canada released a report [14] describing the possible UV exposure from several types of lamps. The report states that at 3 cm distance, the recommended daily exposure to ultraviolet radiation for skin and eye damage (if looking directly at the lamp) was attained between 50 minutes and 5 hours depending on the type of ...
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 ...
For premium support please call: 800-290-4726 more ways to reach us more ways to reach us
[33] [34] [35] A study found that car windows allow 3–4% of ambient UV to pass through, especially if the UV was greater than 380 nm. [36] Other types of car windows can reduce transmission of UV that is greater than 335 nm. [36] Fused quartz, depending on quality, can be transparent even to vacuum UV wavelengths.
Blacklight fluorescent tubes. The violet glow of a blacklight is not the UV light itself, but visible light that escapes being filtered out by the filter material in the glass envelope. A blacklight, also called a UV-A light, Wood's lamp, or ultraviolet light, is a lamp that emits long-wave ultraviolet light and very little visible light.
Photokeratitis can be prevented by using sunglasses or eye protection that transmits 5–10% of visible light and absorbs almost all UV rays. Additionally, these glasses should have large lenses and side shields to avoid incidental light exposure. Sunglasses should always be worn, even when the sky is overcast, as UV rays can pass through ...
The human eye is a wondrous thing. It is considered the body’s most complex organ after the brain and contains over 2 million working parts. About 80% of all learning happens through vision. So ...