 Researchers can use Cryogen Spray Cooling to protect the skin epidermis during laser therapy to decrease treatment pain, allow safe treatment of darker skin types, and safe use of high laser fluences. Cryogen Spray Cooling with Tetrafluoroethane has been incorporated into many Food and Drug Administration approved, commercially available laser devices currently used for treatment of vascular lesions, hair removal and non-ablative skin rejuvenation. 