How many sunscreen times a day? In summer, ultraviolet rays are very strong, so everyone should do a good job of sunscreen. The simplest basic method is to apply sunscreen, but it is also skillful to apply sunscreen. How to apply sunscreen several times a day? Let's talk with you today.
How many sunscreen times a day
In summer, there are different opinions about applying sunscreen several times a day, which is mainly determined by different sunscreen needs, and different SPF values have different sunscreen time,
Office sunscreen: white collar mm, sitting in the office every day, just wipe pf15pa + sunscreen, reapply every 4-5 hours, the effect is better.
Sunscreen for outdoor sports: if you go out of the street in hot summer, you should choose spf25-30pa + + sunscreen and reapply it every 3-4 hours.
Swimming sunscreen: summer like swimming mm attention, the best choice of sunscreen is waterproof, and to use spf30pa + + + above, every 1-2 hours to rub again.
How often does daub sunscreen fill good?
How often to apply sunscreen has something to do with the current environment.
If it's an office worker working indoors, it's OK to wipe it again at noon.
If you are outdoors, you need to re apply it every 2-3 hours, because sunscreen will oxidize ultraviolet rays and lose its sunscreen effect.
And in the swimming pool or need to be in the seaside activities, generally every time out of the swimming pool or out of the sea, have to wipe once. Although most of the sunscreens are waterproof now, they will be washed once after coming out of the water to reduce the effect of sunscreen.
How much sunscreen at a time
The amount of each application should be the volume of a golf ball!
According to dermatologists, for a man weighing 70 kg, sunscreen should weigh one ounce (about 28 grams), which is equivalent to the size of a golf ball and the amount to fill a wine glass. For women with lighter weight, the dosage can be reduced appropriately, about 20g each time.
When you use sunscreen, you must apply enough sunscreen. The correct use of sunscreen can make the sunscreen effect get twice the result with half the effort. Sunscreen does not mean that any amount of sunscreen will have an effect, but to be applied to every square centimeter of skin has 2mg sunscreen, can achieve the desired effect, so girls in the use of sunscreen, must apply enough.
Sunscreen needs to be applied in advance
Sunscreen to achieve sun protection and ideal effect, we must apply it 15-20 minutes before going out. Because sunscreen does not immediately have sunscreen effect after it is applied. Sunscreen also needs a certain amount of time to absorb, only after the skin is absorbed, the skin surface will form a protective film to resist ultraviolet rays, so that the skin can achieve the real effect of sunscreen.
Don't mix sunscreen
Be sure not to mix different brands of sunscreen. Because the ingredients of each brand of sunscreen are different, if the sunscreen is mixed, it will not only repel each other, but also fail to achieve the ideal sunscreen effect, and even cause allergy. Especially for sensitive skin, we must pay attention to it.
Selection of sunscreen products
SPF refers to the product's ability to protect against UVB, that is, the ability to prevent skin redness and sunburn. Generally speaking, it takes about 20 minutes for a person's skin to produce normal amount of erythema, that is, without any sunscreen measures, the skin will turn red after 20 minutes of exposure in the sun. If the SPF value of sunscreen is 8, apply it once. In theory, its protection time for the skin is 20 & times; 8 = 160 minutes or so. If you choose sunscreen with SPF 15, you can stay in the sun for 15 times, that is 300 minutes, and so on. But in fact, people's skin's tolerance to ultraviolet rays in the sun varies from person to person, from time to time, and from place to place.
It can be seen that different sunscreen products should be used in different environments. Employees or women working indoors can choose SPF10 or so and PA +. People who are more likely to tan or sensitive to strong light or who often work or move outdoors can use SPF20 or PA +; When walking in the hot sun or swimming on the beach, you should choose SPF30 with good water resistance and sweat resistance and PA + + + strong sunscreen.
However, we should not blindly pursue the SPF value. In fact, SPF is not directly proportional to the sunscreen effect. SPF15 sunscreen can resist 93% of UVB, while spf34 sunscreen can only resist about 4% more UVB. At the same time, products with too high SPF and PA may be greasy or have poor skin continuity, which may easily block pores and cause acne or folliculitis. <