Wonder how they survived, mom and dad and all my relatives worked long hours in the sun.  Not one of them had skin cancer.  Mom lived to 98, uncle John on my dad's side to 94 and all of them lived to their 80's.  
"

Myth 9: I don’t need sunscreen inside. 

False. Spending time indoors shouldn't mean skipping SPF. That’s because UV rays can come through windows.  

“Most windows, unless they are tempered glass or have a UV-filtering film, allow passage of UV rays,” Patel says. 

Likewise, she notes that wearing SPF – even on days you’re mostly inside – protects your skin from UV exposure you might not even recognize you’re getting, like while driving or walking through the parking lot to the grocery store. 

“Most people would say they were inside all day, but there is cumulative incidental exposure that occurs,” she says.