It is okay to shower immediately after using a tanning bed. Tanning beds give off UVA radiation, which penetrates skin; showering cannot wash away the effects of tanning. It is recommended to wait four to six hours after using a sunless tanning technique before showering, swimming or sweating.
UVA radiation penetrates the epidermis and dermis layers of skin. UVA is damaging to skin. Melanin is produced as a response to the damage to try to protect skin against UVA radiation. Melanin is what causes the appearance of a tan. Tanning beds give off up to 12 times as much UVA radiation as the sun.