Which light is known to penetrate deeper into the skin, affecting the dermis layer?

UVA rays are known for their deeper penetration into the skin, reaching the dermis layer. Unlike UVB rays, which primarily affect the epidermis and are responsible for causing sunburn, UVA rays can penetrate more deeply and contribute to skin aging and certain types of skin damage, including the breakdown of collagen and elastin. This is significant in esthetics because understanding the effects of different types of light on the skin can help practitioners select appropriate treatments and protective measures for clients, particularly in the context of sun exposure and the use of artificial tanning devices.