@Viss My understanding is that the PA system is for indicating it can deal with UVA as most sunblocks have only dealt with UVB.

Based on those Supergoop ingredients it's using Homosalate at 5% concentration to get the PA+++ rating and the table in the link below it would be like SPF2 (yes, two) and start losing effect after 45 minutes.

That's pretty terrible if you think about it. It's better than nothing but it's not helping very much with UVA. Blocking UVA seems to be a difficult problem.

https://twindly.com/blog/sunscreen-cheat-sheet/


Tinosorb is very photostable so it should last many hours in the sun with full protection.