Today, we are going to talk about how to use sunscreen correctly, which included the importance of sun protection, the steps for using sunscreen and the cautions.
The importance of sun protection
With the global warming effect, the ozone layer is gradually thinning and ultraviolet rays are getting stronger and stronger. According to different wavelengths, ultraviolet rays can be divided into short-wave ultraviolet (UVC 200-190nm), medium-wave ultraviolet (UVB290-320nm), and long-wave ultraviolet (UVA 320-400nm). Short-wave ultraviolet rays are almost all absorbed by the ozone layer in the stratosphere of the atmosphere, medium-wave ultraviolet rays are absorbed by 90%or more, and long-wave ultraviolet rays can penetrate the atmosphere and reach the earth’s surface.
Therefore, what we usually call sunscreen is mainly to prevent the damage caused by medium-wave (UVB) and long-wave (UVA) ultraviolet rays to the skin. Among them, UVB has medium penetrating power and can penetrate the epidermis layer, which is the root cause of skin sunburn; while UVA has strong penetrating power and can reach the dermis layer of the skin, which is the culprit of skin tanning and aging.
Steps for using sunscreen
- Complete the basic skincare routine
Complete the basic skin care procedures first, usually in the order of cleanser – toner – essence – lotion – cream, but the choice of skin care products depends on personal needs.
- Take an appropriate amount of sunscreen
After a basic skincare routine, take out an appropriate amount of sunscreen. Regarding the amount of sunscreen to be used, it can be estimated by the size of a dollar coin or about 1g of weight; then put the sunscreen on the forehead, cheeks, nose, chin and other areas, and then use your fingertips to spread the sunscreen evenly from the inside out, then gently pat evenly.
Cautious
- It is best to apply sunscreen 20-30 minutes before going out in order to exert its best sunscreen effect. If you go out immediately after applying sunscreen, you will still get sunburned and tanned before the sunscreen has time to work.
- No matter how good the sunscreen is, the effect will weaken over time, so you need to reapply sunscreen every 2 to 3 hours. If you wear makeup, you can use sunscreen spray to reapply.