Sun Protection & UV Rays

Is Sun Protection Important? What Are UV Rays?

The sun is the natural source of ultraviolet (UV) radiation, which is invisible to the human eye. UV radiation is divided into three types: UVA, UVB, and UVC.

• UVA rays (320–400 nm) penetrate both the epidermis and dermis, reaching deep into the skin. They are responsible for tanning, premature skin aging, and DNA damage.

• UVB rays (280–320 nm) mainly affect the outer layer of the skin (epidermis) and are the primary cause of sunburn and skin cancer.

• UVC rays (200–280 nm) are negligible because they are effectively filtered out by the earth’s stratospheric ozone layer.

UVA radiation remains relatively constant throughout the day and year. UVB rays, on the other hand, are more intense in summer than in winter, strongest around midday compared to morning or late afternoon, and significantly more powerful near the equator and at high altitudes.

UV radiation can also be emitted by artificial sources such as tanning beds, sun lamps, and industrial tools like welding equipment. Surfaces like sand, snow, concrete, and water can reflect up to 85% of sunlight, significantly increasing UV exposure. UV rays can penetrate up to 60 cm into water, meaning your skin can still be affected in and under water.

The minimum amount of UV radiation needed to cause skin redness depends on various factors, including skin type and thickness, the melanin content in the epidermis and its ability to produce melanin after sun exposure, as well as the intensity of UV radiation.

Effective skin protection against both UVA and UVB radiation is the most important preventive strategy for reducing the risk of skin cancer and premature aging.

Physical sun protection, such as clothing or mineral-based sunscreen, plays a crucial role in lowering the incidence of UV-related skin issues by forming a barrier on the skin that scatters and reflects harmful UV rays.