In the spring, when it is still warm, flowers are blooming and spring is bright. When people take off their heavy winter clothes and enjoy the warm sunshine, they should pay attention to prevent the damage of UV rays to the skin. UV rays in the sun can be divided into long-wave, medium-wave and short-wave according to wavelength. Short-wave UV rays are the most damaging to human skin, but fortunately they are blocked by the atmosphere. Only medium-wave and long-wave UV rays can reach the ground and hit our skin. Excessive exposure to medium-wave UV radiation mainly causes burning and stinging of the skin, redness, swelling, peeling and even blistering, which is physical damage. Long-wave UV radiation mainly causes rashes, blisters and itching in people who are allergic to UV radiation, which is a metabolic reaction. Due to the cold climate in winter, people go out less, and the short sunshine time and weak UV intensity, the melanin particles in human skin decrease, making the skin white. The reduction of melanin particles that can absorb and block UV rays makes the skin less able to resist UV damage. With the arrival of spring, the sunshine time gradually lengthens, coupled with the dry climate with few clouds and less moisture in the air, the blocking of UV rays decreases, making the intensity of UV rays increase significantly. The warming climate also increases people’s outdoor activities, while the skin’s ability to protect against UV rays is the weakest time of the year, if we don’t pay attention to strengthen protective measures, the warm spring day will easily bring serious damage to our skin. In some cases, the skin may become red, itchy and peeling, and in some cases, the skin may become edematous and blistered, leaving pigmentation behind. For people with endocrine disorders, melasma or freckles, the warm spring day will unknowingly trigger or aggravate your pigmentation. In addition, the stimulation of UV rays can also trigger or aggravate eczema, seborrheic dermatitis and many other skin diseases. The way to protect your skin from UV rays is actually very simple and effective. For example, when you go out to travel, shopping with a beautiful umbrella, wear a wide brim baseball cap or fashion cap, that can be effective sun protection, and add a few romantic and fashion. People who are more sensitive to UV rays, you can also apply sunscreen on the exposed parts of the skin, pay attention to the choice of product identification note UVB and UVA words, that is, on the medium-wave UV rays and long-wave UV rays have a protective effect of sunscreen.