PA++++ vs. 'Broad Spectrum': How to Read UVA Protection
That PA++++ on your Japanese sunscreen tells you something the US 'broad spectrum' label can't — here's how to decode both.
The Japanese/Korean PA system grades UVA via the Persistent Pigment Darkening (PPD) method, where PA++++ corresponds to PPD 16 or greater, whereas the US 'broad spectrum' label is a pass/fail critical-wavelength test (90% of absorbance at or above 370 nm) that does not grade UVA strength.
Photobiology researchers point out that PPD-based grading gives consumers a graduated measure of UVA defense, while the US critical-wavelength method only certifies that a product crosses a single threshold — meaning two 'broad spectrum' products can differ substantially in actual UVA strength.
Questions we get a lot
What does PA++++ actually mean?
PA is a UVA rating used mainly in Japan and Korea, based on the Persistent Pigment Darkening (PPD) method. PA++++ is the highest grade and corresponds to a PPD of 16 or greater. More plus signs indicate stronger graded UVA protection.
Is US 'broad spectrum' as good as PA++++?
Not necessarily, because they measure differently. The US 'broad spectrum' label is a pass/fail critical-wavelength test (90% of absorbance at or above 370 nm) and does not grade UVA strength. A PA++++ product gives you a graded measure (PPD 16+), so it conveys more information about UVA defense.
r/AsianBeauty: 'Is PA++++ better than a US sunscreen that just says broad spectrum, or are they the same thing?'