If you’re buying sunscreen from a Japanese brand, you’re likely to come across the PA rating system.
PA stands for protection grade of UVA system and is the Japanese measurement of sun protection, which is based on the Persistent Pigment Darkening (PPD) reaction reading at 2-4 hours of sun exposure. According to info from the wiki, the Persistent Pigment Darkening (PPD) method is a method of measuring UVA protection, similar to the SPF method of measuring UVB light protection.
These are the three levels of protection that are commonly seen:
PA+, PA++ and PA+++.
PA+ provides some UVA protection with a factor of PPD 2-4
PA++ provides moderate UVA protection with a factor of PPD 4-8
PA+++ provides good UVA protection with a factor of PPD > 8
Which means, you’re better off picking a sunscreen with PA+++ which will provide you with the greatest protection.
© www.vivawoman.net copyright notice
_______________________________________________________
I'm Sesame and Viva Woman is a 
I appreciate that some of you find my articles interesting and wish to share them. There are many ways you can share, such as via social media but copying or lifting content is definitely not the right way. Please note that all material here is copyrighted and I have a 
Have a question for me? Have something interesting to share with me? Then contact me! You may like to send me an email to vivawoman[at]gmail[dot]com. I will try to respond as soon as soon as I am able to. Emails requesting for link exchanges or containing unsolicited sales messages will be ignored.
Thank you very much for this article. Could you explain the difference between the Persistent pigment darkening (PPD) as described in the JCIA and Persistent pigment darkening (PPD) for the UE, for the UE is the methof based on the JCIA but modified by the AFSSAPS. What is the AFSSAPS has modified in this technic?
Thank you very much,
Regards