What do 30+ and 50+ on sunscreen mean?

SPF30 means that the effective sunscreen time is 300 minutes, and SPF50 means that the effective sunscreen time is 500 minutes.

SPF？ 15 can block 93% of UVB, 30 can block 97%, and 50 can block almost 98%. That is to say, if these sunscreens really only have SPF? About 30, that's almost enough. There is no need to increase the risk of skin irritation for the increase of 1%. After all, the concentration of sunscreen has almost doubled from SPF 30 to SPF 50.

There are several+signs after PA, which is the key index to protect UVA, and UVA is the ultraviolet ray that we should prevent most, which will cause skin inflammation, melanin formation, collagen and skin cell damage and skin aging.

Is spf30 the most suitable sunscreen for daily use? PA+++。

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How to choose a sunscreen that suits you?

1, oily skin

This kind of skin should choose water-based sunscreen with strong permeability, oil-free formula, refreshing and not greasy, and not blocking pores. Never use sunscreen oil, and use physical sunscreen products with caution.

2, dry skin

This kind of skin can moisturize, and sunscreen products with hydrating effect and enhancing skin immunity are added. Nowadays, many sunscreen products have added hydrating and antioxidant effects in addition to sunscreen.

3. Sensitive skin

Professional sunscreen products of skin-sensitive skin care brands, or product descriptions clearly state "passed allergy test", "passed dermatologist's clinical test for children" and "no perfume or preservative". It is best to choose physical sunscreen products, mainly chemical sunscreen, which is irritating and harmful to the skin to varying degrees!

Baidu encyclopedia -SPF