Solar radiation consists of several components, including UVA radiation. Unlike UVB radiation, which primarily causes sunburn, UVA radiation penetrates deeper into the skin. Here it can cause premature skin aging, such as the formation of wrinkles and pigment spots, and it also contributes to the development of certain types of skin cancer. Sunscreen products providing protection against this type of radiation are often marked with the "UVA" symbol in a circle. This designation guarantees that the level of protection against UVA radiation reaches at least one third of the value of the stated SPF factor, which measures protection against UVB. Another rating system, used primarily for Asian products, is the PA scale, for example "PA+" to "PA++++", where a higher number of plus signs indicates a higher degree of protection.
