SGROW
UVA band has a wavelength of 320 to 400 nm and is also known as long-wave ultraviolet rays associated with the tanning effect. It has strong penetrating power and can pass through most transparent glass and plastics. Over 98% of the long-wave ultraviolet rays in sunlight can penetrate the ozone layer and clouds to reach the Earth’s surface. UVA can reach the dermis layer of the skin, damaging elastic fibers and collagen fibers, leading to tanning. UVA ultraviolet rays at a wavelength of 360 nm correspond to the phototropic response curve of insects and can be used to create insect traps. UVA ultraviolet rays with wavelengths between 300 and 420 nm can pass through special colored glass tubes that completely block visible light, emitting near-ultraviolet light centered around 365 nm, which can be used for mineral identification, stage decoration, and currency verification.
UVB band has a wavelength of 275 to 320 nm and is also known as medium-wave ultraviolet rays associated with the erythema effect. It has moderate penetrating power, and its shorter wavelength portion is absorbed by transparent glass. Most of the medium-wave ultraviolet rays in sunlight are absorbed by the ozone layer, with less than 2% reaching the Earth’s surface, particularly strong in summer and during the afternoon. UVB ultraviolet rays cause erythema in humans, promote the metabolism of minerals and the formation of vitamin D, but prolonged or excessive exposure can lead to tanning, redness, swelling, and peeling of the skin. Ultraviolet health lamps and plant growth lamps emit UVB using special glass that does not transmit light below 254 nm and phosphors with peaks around 300 nm.
UVC band has a wavelength of 200 to 275 nm and is also known as short-wave sterilizing ultraviolet rays. It has the weakest penetrating ability and cannot pass through most transparent glass and plastics. Short-wave ultraviolet rays in sunlight are almost completely absorbed by the ozone layer. Short-wave ultraviolet rays can cause significant harm to the human body; even short-term exposure can burn the skin, and prolonged or high-intensity exposure can lead to skin cancer. Ultraviolet sterilizing lamps emit UVC short-wave ultraviolet rays.
UVD band has a wavelength of 100 to 200 nm and is also known as vacuum ultraviolet rays, which means that almost none reach the Earth’s surface.
