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Given the following post, respond as if you're commenting on Reddit:
human
Can you get sunburnt behind glass?

Now that i found the right subbreddit..

Hey Askscience :) 

It's coming up on summer her in Australia and have always wanted to confirm the suggestion by a friend that you cannot get sunburnt behind glass, as properties of the wave are changed once they pass through the glass?

When i drive around in my car on a warm day with the windows up i can quite easily feel the heat on my skin, however does heat on the skin always equate to sunburn? Or is the fact i feel more heat behind glass to do with the change in the wave?
gpt
From the Wiki

>Ordinary glass is partially transparent to UVA but is opaque to shorter wavelengths, whereas silica or quartz glass, depending on quality, can be transparent even to vacuum UV wavelengths. Ordinary window glass passes about 90% of the light above 350 nm, but blocks over 90% of the light below 300 nm.[6][7][8]

UVA isn't as harmful but over extended time will give you a sunburn.  UVA is 400-315nm.

UVB is your main Sunburn exposure and where most people get into trouble with skin cancer, it is 315-280nm.  Glass blocks the smaller half of this very well, but leaves a sliver in the large end.

UVC is even higher energy, but the air itself starts to block most of this, it is a key component in the formation of the Ozone in the Ozone layer.  


So yeah, you can get a sunburn from behind glass, but it will take a lot longer and it will be from larger wavelengths of UV compared to direct sunlight, so your cancer risk is lower (note: not gone).  Obviously treated or tinted glass can be made to block all the UV.