Do you have to reapply sunblock within a certain time zone even though you don't go directly into the sun?

Question

What if you stay in the shade most of the time during the day?

Answer 1

ideally, apply 15 minutes before going outside, reapply anywhere from 5-8 hrs later, depending on the brand you used.
Don't forget your ears!

Answer 2

If it is light shade, then you are getting about 50% of the UV, so then you would need to reapply it if you are out all day. Or if you are near water, a lot of that light gets reflected at you. I have very fair skin, and I don't burn ever in deep shade.

Answer 3

read the instructions they usually recommend how often to apply, follow the instructions regardless of whether your in direct sunlight.