Ultraviolet (UV) radiation is categorized by wavelength in how many bands?

Ultraviolet (UV) radiation is categorized into three distinct bands based on wavelength: UV-A, UV-B, and UV-C. Each of these bands has different characteristics and impacts on organisms and materials.

• UV-A (320-400 nm) is the longest wavelength and is less energetic than UV-B and UV-C. It can penetrate deeply into the skin and is often associated with skin aging and long-term skin damage.

• UV-B (290-320 nm) has a medium wavelength and is responsible for causing sunburns and has a significant role in the production of vitamin D in the skin.

• UV-C (100-290 nm) has the shortest wavelength and is the most energetic. It is primarily absorbed by the ozone layer and does not reach the Earth's surface in significant amounts, but it can be harmful to living organisms and is used in various types of sterilization.

Understanding these three bands is crucial for comprehending their effects on health, environmental science, and technology applications. This classification helps in assessing risks associated with UV radiation exposure and in developing protective measures.