Sunscreen and UV

["Wes Van Pelt" <WesVanPelt@ATT.NET>]

Ruth W. said:

So use that sunscreen and avoid leaking Freons into the air.  

Hi Ruth and All,

 

I am wondering exactly how sunscreen blocks UV radiation. When you put it on the skin, it "disappears" so it is transparent to visible light. And the layer of sunscreen is quite thin. I read recently that there are 5 or 6 different chemical compounds that can be used as sunscreen.

 

So, what is the mechanism that protects the skin from the effects of UV? Does the mechanism include some reaction with the skin? Would sunscreen spread on window glass to the same thickness screen out the same fraction of UV as on the skin?

 

Just wondering,

 

Wes

Wesley R. Van Pelt, Ph.D. CIH, CHP

Wesley R. Van Pelt Associates, Inc.

Radiation Safety and Environmental Radioactivity

WesVanPelt@att.net