Ultraviolet (UV) refers to the light with a wavelength of 100 ~ 400nm in sunlight, which can be divided into UVA with a wavelength of 320 ~ 400nm, UVB with a wavelength of 280 ~ 320nm and UVC with a wavelength of 100 ~ 280 nm.

The longer the wavelength, the deeper the penetration; the shorter the wavelength, the stronger the energy. UVA is able to penetrate deep into the dermis, causing tanning and sunburn. Long-term irradiation can cause skin aging. The stronger UVB causes redness, sunburn, and carcinogenesis, while UVC can be blocked by the ozone layer from reaching the surface.

Precautions

• Do not expose yourself to direct sunlight. Wear sun hats, clothes with long sleeves or put up a parasol.
• Avoid to go out to expose yourself to direct sunlight at 10:00 am ~ 2:00 pm when UV damage is highest.
• For both sunscreen cream and oil, choose products with SPF 30 or above or with UVA protection (PA++ or above). It is suggested that applications are required every 2 hours or after a shower, swimming and sweating.
• UV rays still penetrate clouds and glass, so sunscreen is still needed in cloudy days, indoors and cars.
• If you get sunburn or a tan accidentally, please consult your doctor for treatment. Do not use over-the-counter drugs or whitening agents to smear, so as to avoid skin damage.