Which type of UV radiation is known for its strong anti-bacterial effect?

UV-C radiation is known for its strong anti-bacterial effect due to its germicidal properties. This type of ultraviolet light has a wavelength range of 100 to 280 nanometers, which is effective in disrupting the DNA of microorganisms, leading to their inactivation or death. Because of this property, UV-C is widely used in various sterilization processes, including water purification and in hospitals to disinfect surfaces.

In contrast, UV-A and UV-B have different effects. UV-A (315 to 400 nm) penetrates the skin more deeply and is primarily associated with skin aging and the formation of wrinkles, while UV-B (280 to 315 nm) is primarily responsible for sunburn and plays a significant role in the development of skin cancer. However, neither UV-A nor UV-B possesses the same level of anti-bacterial effectiveness as UV-C. Visible light is not considered to have any germicidal properties that are relevant in the context of bacterial inactivation.