Three Types of UV Light

There are three types of UV light:

ULTRAVIOLET A (UVA)

Ultraviolet A has the longest wavelength of the UV light spectrum and penetrates directly into the dermis of the skin, killing DNA cells and damaging the collagen and elastin.

UVA light is the light that is often used in tanning beds.

ULTRAVIOLET B (UVB)

Ultraviolet B light is also called the burning light because it is most associated with sunburns. Excessive use of both UVA and UVB light can cause skin cancers.

ULTRAVIOLET C (UVC)

Ultraviolet C light is blocked by the ozone layer.
If the Earth loses its protective layer of ozone, life as we know it will no longer exist. UVC is effective at killing bacteria, viruses, mold and other pathogens.

CAUTION:

Although the application of UV light can be beneficial, it must be done with the utmost care in a proper manner by a qualified professional — overexposure can lead to skin damage and skin cancer.

UV light has been used to kill bacteria on the skin and to help the body produce vitamin D; it is used in a weaker form to cure UV gel nails. Dermatologists also use UV therapy in addition to drugs for the treatment of psoriasis.