Ultraviolet (UV) radiation is a part of the electromagnetic spectrum with wavelengths ranging from 10 nanometers (nm) to 400 nm. UV radiation is invisible to the human eye but has a significant impact on living organisms and the environment.
Sources of ultraviolet (UV) radiation
Natural sources of ultraviolet radiation:
- Solar radiation – the sun is the primary source of ultraviolet radiation that reaches the Earth’s surface.
- Cosmic radiation – ultraviolet radiation can also originate from space, such as from galaxies, quasars, or supernovae. However, this radiation is filtered by the Earth’s atmosphere and does not reach the surface in significant amounts.
Artificial sources of ultraviolet radiation:
- UV lamps – UV lamps are artificial sources of ultraviolet radiation used in various applications, including water treatment, sterilization of instruments and materials, as well as in cosmetics and medicine.
- Light-emitting diodes (LEDs) – ultraviolet LEDs (UV-LEDs) are also artificial sources of ultraviolet radiation used in various applications, including water treatment, air disinfection, medicine, and science.
UV radiation is divided into three categories based on wavelength: UV-C (100-280 nm), UV-B (280-315 nm), and UV-A (315-400 nm). Each of these categories has its own characteristics and properties.
UV-C radiation (100-280 nm) has the shortest wavelength among the three types of ultraviolet radiation and the highest energy. This radiation can be harmful to living organisms, including humans, who may experience skin and eye burns from prolonged exposure to UV-C rays.
However, UV-C radiation also has bactericidal and virucidal properties, so it is used in industrial processes and water supply systems to disinfect surfaces, water, and air. For disinfecting water and air, lamps with UV-C radiation are typically placed in special devices that allow air or water to pass through the radiation zone.
UV-C radiation can also be used for sterilizing medical equipment, instruments, packaging, and other industrial materials, reducing the risk of the spread of infectious diseases and ensuring safe working conditions. However, for safe use of UV-C radiation, it is necessary to follow all necessary safety precautions and use specialized protective equipment.
UV-B (ultraviolet radiation type B) is shortwave ultraviolet radiation in the spectrum of ultraviolet light, with wavelengths ranging from 280 to 315 nm. This type of ultraviolet radiation has high energy and can cause damage to cells and tissues, including the skin and eyes, if a person is in close proximity to the radiation source or is exposed to direct rays without proper protection. However, UV-B radiation also plays an important role in the synthesis of vitamin D in the skin, which is necessary for bone health and the immune system.
UV-A radiation (315-400 nm) has slightly longer wavelengths than UV-C and lower energy. UV-A rays are less harmful to humans than UV-C, but prolonged exposure to the skin can lead to pigmentation, changes in collagen structure, and an increased risk of skin cancer.
UV-A rays are typically used in tanning beds and in cosmetology for the treatment of certain dermatological conditions, such as psoriasis and eczema. UV-A is also used in fluorescent lamps.
UV-A radiation does not have bactericidal or virucidal properties like UV-C.
UV radiation can have both positive and negative effects on living organisms. For example, it can promote the production of vitamin D in the human body, but it can also lead to skin burns, accelerated aging, and an increased risk of skin cancer. Since UV radiation can be harmful to health, it is important to use safety measures when working with UV radiation, such as wearing protective eyewear and skin protection.