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Can aluminum foil block the sun's UVA rays?

  1. Mar 13, 2014 #1
    Hello everyone. I was just curious if aluminum foil could block the sun's UVA rays. I have my home office and the sun always gets in and hits me. I know sunlight can cause early photoaging and cancers, so I want to block out as much UVA rays as possible. I do wear sunscreen, but I prefer blocking it another way while I'm in my home office. Wearing sunscreen in my house all day is not my cup of tea (it dries me). I'm planning on making a sort of little shield made of Aluminum Foil that I can put right next to my desk, and angle it so that it protects me from the sun's UVA rays.

    I'm not a physics person and I work in statistics, so I forgot most high school physics. So I basically would love to know if Aluminum Foil is enough to block away the sun's UVA rays??? If not, then what else could block them??? Thank you all.
  2. jcsd
  3. Mar 13, 2014 #2


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    hi there solid snake

    if you cannot see through ( ie its opaque) the Al foil then it will stop UV
    there are window filter films available that allow visible light whilst substantially filtering UV
    see this link

  4. Mar 13, 2014 #3
    Thanks. It makes sense. Now that you mention it, I do remember learning that in high school (at least what an opaque can and can't do). This is a relief.

    But this sparks another question. What about UVA rays from ceiling light??? I remember someone mentioning that ceiling light gives off a ton of dangerous UVA radiation, and could have similar affects as the sun, but I've heard others tell me it's nonsense.

    Well thank you very much. I'm off to construct my shield!!!!
  5. Mar 13, 2014 #4


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    The white plastic fittings and white plastic starter case, with time, turn yellow on their surfaces facing the light from ceiling fluros, so this demonstrates that there is some UV radiated by these tubes. The wavelengths, and relative intensity, are not discernible without proper tests.
  6. Mar 13, 2014 #5


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    You won't be able to get a tan indoors, but UVA is always present to some degree outside since, unlike UVB, it is not blocked by the ozone layer.


    Blocking out all UVA is not healthy since humans need some exposure to UVA to generate vitamin D.
  7. Mar 13, 2014 #6
    Fluorescent lights do emit a small amount of UVA's (Not enough to worry about), Incandescent lights and LED lights emit no UV's at all.
  8. Mar 13, 2014 #7


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    Last edited by a moderator: May 6, 2017
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