Not really. It all depends on your circumstances, the country you live in, if there are objects outside your window like trees/other houses etc. If you're sitting by the window - yes, but otherwise - mostly not necessary. Only a fraction of rays will reach you and even strong sunscreen doesn't provide 100% protection anyway.
I usually check the uv index where I live I apply sunscreen pretty much everyday but dermatologists recommend sunscreen only if uv index is 3 or higher so I apply everyday but if the uv index is lower than 3 I don’t bother reapplying
The Picky community helps you discover new products through discussion boards, honest reviews, expert articles and redeemable free product rewards. #GetPicky!