5. Although unlikely, you can get sunburnt through glass and windows
Regular glass filters out 97% of UVB rays, much like SPF 30 suncream, so whilst it's unlikely you'll get burnt through glass, it's not impossible. The risk of burning can also depend on factors like the type of glass, the time of day, and the length of exposure time.
Windscreens on cars provide high protection against UVB rays, but it's still worth wearing suncream, especially on long drives. UV rays can also damage your eyes, much like sunburn damages your skin, so you should wear sunglasses with UV protection to shield your eyes.