Ultraviolet light represents a portion of the sun's electromagnetic spectrum. It is the wavelength band immediately beyond the violet end of visible light. All bands of UV light are present throughout the environment - it comes from the sun, light fixtures, electrical devices, etc. The UV range of the spectrum is characterized by wavelengths between 100 and 400 nanometers (nm).

Absolutely. There is a growing body of well-conducted, validated scientific research demonstrating that the production of the activated form of vitamin D is one of the most effective ways the body controls abnormal cell growth. Moderate exposure to sunlight is the only way for the body to manufacture the vitamin D necessary for producing activated vitamin D. See similar questions...

In addition to the superior color rendering abilities, SoLux has been engineered to have very low heat (IR) output and ultra-low UV output. That combined aspect of extremely high color rendering and extremely low UV and low IR is extraordinary. It means that with SoLux, you will have the brilliance of daylight without the negatives aspects of UV and IR. The result is a superior presentation that won't cook or bleach the subject being illuminated. See similar questions...

Solar energy reaches the earth over a range of wavelengths. Ultraviolet light or UV (300 to 380 nanometers) is short wavelength radiation. It is invisible radiation and counts for approximately 2 percent of the radiation reaching the earth. See similar questions...

For information on the UV properties of the euro banknotes, see the guidelines on how to identify counterfeit euro banknotes. See similar questions...

Ultraviolet light technology is a non-chemical approach to disinfection. This process is simple and inexpensive, requiring very low maintenance. Ultraviolet light sanitizers utilize germicidal lamps that are designed and calculated to produce a specific dosage of UV-C light (usually at least 16,000 microwatt seconds per square centimeter). The principle of design is based on a product of time and intensity. Both are necessary for successful disinfection. See similar questions...

Germicidal ultraviolet light (UV-C light) deactivates the DNA of bacteria, viruses and other pathogens and destroys their ability to multiply to cause infection and disease. Specifically, UV-C light causes damage to the nucleic acid of microorganisms by forming covalent bonds between certain adjacent bases in the DNA. The formation of such bonds prevent the DNA from being unzipped for replication, and the organism is unable to reproduce. In fact, when the organism tries to replicate, it dies! See similar questions...

All light is given off at different wavelengths. For example if you see a rainbow, you will notice that the colors are always in a specific order from red all the way to blue. You are able to see each color due to their individual wavelength. These wavelengths are part of the visible portion of the electromagnetic spectrum. UV light is at a wavelength of 254nm (nanometers), and is not visible to the naked eye. See similar questions...

Light is divided in to many different categories based on its wavelength. Most of the light that reaches the earth's surface is visible light or infrared light, but a small percentage consists of ultraviolet light. This light is divided into ultraviolet A, B, and C. Ultraviolet light has many effects on the skin, the most common being a sunburn and the formation of pigment or a suntan. See similar questions...

Ultraviolet phototherapy is the use of specific wavelengths of the sun's natural spectrum for the treatment of skin disorders such as psoriasis, vitiligo and atopic dermatitis (eczema). Phototherapy devices use either the short wavelength Ultraviolet-B (UVB) rays or the longer rays of Ultraviolet-A (UVA). UVB light produces biological reactions within the skin that lead to clearing of the lesions. UVB light is also very efficient at producing vitamin D3 in our skin; essential to good health. See similar questions...

The Ultraviolet (UV) Index provides important information to help you plan your outdoor activities and avoid over-exposure to the damaging rays of the sun. Developed by the National Weather Service (NWS) and the Environmental Protection Agency (EPA), the UV Index is issued daily as a national service. It is a forecast, of the amount of ultraviolet rays expected to reach the Earth's surface when the sun is highest in the sky. See similar questions...

Although exposure of Ryton? PPS to UV light may cause some surface degradation, the properties of the bulk material will be relatively unaffected. Several Ryton? PPS compounds (R-4, R-4 02, R-4XT, R-4 02XT, R-7 02, R-10 5002C, and R-10 7006A) have been rated suitable for outdoor use with respect to UV light exposure, water exposure and water immersion, in accordance with UL746C. See similar questions...

CD ozonators use an exposed electrical arc to generate ozone. A byproduct of Corona Discharge ozonation is nitric acid. When mixed with moisture from the humidity in the grow space this corrosive “syrup” contaminates the surfaces that produce the ozone. This requires frequent cleaning of the arcing surfaces or the contamination will reduce the ozone output of the generator. UV lamps use concentrated ultraviolet light waves to produce ozone. See similar questions...

In ISO 3664, a CIE rating is referenced and this rating includes a level of UV to be included in daylight sources. UV is a natural component in natural daylight. To simulate true daylight with a man-made light source, including UV is necessary. However, the imaging industry frequently uses optical whitening agents in substrate materials, e.g., paper. These agents absorb energy in the UV area of the spectrum and re-emit them in the visible region of the spectrum, usually in the blue region. See similar questions...

Not necessarily. The effect of clouds on UV radiation is as varied as the clouds themselves. Fully overcast skies lead to reductions in surface UV irradiance. On average, scattered or broken clouds also cause reductions, but short-term or localised UV levels can be larger than for cloud-free skies if direct sunlight is also present. See similar questions...

UV-C rays penetrate the cells of harmful bacteria and viruses in our drinking water, destroying their ability to reproduce. Without this ability, these organisms die and no longer pose a health threat. It is a simple but very effective process, with the system generally destroying 99.99% of harmful microorganisms. See similar questions...