How many levels of PA in sunscreen? Meaning of PA

This is an automatically translated article.

PA index is one of the indicators that show the level of protection against UV rays of sunscreen. Choose a suitable sunscreen to help protect your skin from the harmful effects of UV rays.

1. What is the PA index?

The PA index stands for Protection Grade of UVA, which is an index that measures the ability of a sunscreen to protect the body from UVA rays, published by the Japan Cosmetics Association.
PA is converted from PFA which stands for Protection Factor of UVA. PFA is calculated based on the minimum dose of UVA to produce melasma within 2-4 hours of sun exposure. Currently, sunscreens all provide a long-lasting UVA filter index on the skin, about 4-8 hours for PA++ type, 8-12 hours for PA+++ type, or 16 hours for PA++++ type.
The harmful effects of UVA rays on the body:
Is the type of rays with the largest amount of rays reaching the earth, accounting for 95% of the UV rays reaching the earth. They cause heatstroke. Can penetrate deep into the skin causing changes in the skin. It is the cause of skin cancer and skin aging. Penetrates the cornea and affects the lens and retina. UV rays also have benefits for the body if the right amount of rays helps the body synthesize vitamin D to fight rickets, cure some skin diseases, and stimulate the body's activities.

2. How many levels of PA in sunscreen?

Usually on the sunscreen packaging the PA index is poorly represented by the “+” sign and it is divided into 4 levels
PA+ PA++ PA+++ PA++++ However for some sunscreens, the sign may not be visible. PA index symbol, but instead is abbreviated symbol such as UVA-UVB, UVA/UVB or UVA1, UVA2. Or are the specific symbols of some brands and countries.. For example, SPF 60-12 means SPF 60 and PA+++.
In addition, if you often use sunscreen products from countries such as the UK, My or some European countries. We won't often see brands that offer a PA rating. Instead we see the words "Broad Spectrum" or "Full Spectrum" which means that these sunscreen products have been recognized to limit the harmful effects of both types of UVA and UVB rays.

Chỉ số PA trong kem chống nắng có mấy cấp độ — Thông thường chỉ số PA trong kem chống nắng được chia thành 4 cấp độ

3. Meaning of PA

PA + has the ability to block UVA rays at 40-50%
PA++ is better at blocking UVA rays, at 60-70% and the filter time is about 4-6 hours.
PA+++: Good UVA protection, up to 90%, filter time about 8-12h
PA++++: Very good UVA protection, up to over 95%. Filter time up to 16h.

4. How to choose a sunscreen with a good PA index?

PA is the index against UVA rays, so with products containing higher levels, the sun protection ability, protecting the skin against the harmful effects of UVA rays is better.
Therefore, when going outdoors, you should choose sunscreens with PA +++ or PA++ to provide better protection and longer protection time.
Hope this article helps readers understand the PA index on sunscreen, the levels and the meaning of this index. Help you choose a suitable sunscreen to help protect your skin from the harmful effects of UV rays.

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