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Guide to Digital Preservation from NIST

Little Hamster writes "The scientists working on the Digital Preservation Program at the National Institute of Standards and Technology (NIST) has released an excellent 50 page guide on care and handling of CDs and DVDs for long term storage. It talks about the effects of light, moisture, radiation, scratches, marking, adhesive labels, and even playback on the discs. For those slashdotters who is not familiar with the physical made up of these optical discs, there is a very nice chapter explaining all the background. And if you only want to know how to care for your precious data, there is a one page summary. And yes, they agreed that glued-on labels are harmful."

2 of 190 comments (clear)

  1. Guide to Analog Preservation from LoC by O · · Score: 5, Informative
    Digital is great, but what about all of that 'legacy' analog media you have lying around, like pictures, books, tapes, and LPs?

    The Library of Congress has a guide right here!

    --

    1, 1, 2, 3, 5, 8, 13, 21 -- Mathematics is the Language of Nature.
  2. Re:Looks like CD storage racks got it wrong then.. by mobby_6kl · · Score: 5, Informative

    from the 50-page pdf:
    Physical mishandling of the disc is usually the cause of polycarbonate*
    layer damage. The polycarbonate may also flex or bend if
    stored for a long period of time in a nonvertical position.

    and
    Long-term horizontal storage, particularly in a
    heated environment, can cause the disc to become permanently
    bowed. While the data may still be intact, the disc may not operate
    properly in the drive or permit the laser to follow the track.


    *3.1 Polycarbonate (Plastic) Substrate Layer
    The polycarbonate substrate makes up most of the disc, including
    the area that is read by the laser (opposite the label side on CDs). It
    is present on both sides of a DVD, even a "single-sided" disc with a
    label on one side. This substrate provides the disc depth necessary
    to maintain laser focus on the metal and data layers. It also gives the
    disc enough strength to remain flat. Anything in or on the polycarbonate
    layer that interferes with the ability of the laser to focus on
    the data layer will result in the misreading of data. Accordingly, fingerprints,
    smudges, or scratches, as well as such substances as dirt,
    dust, solvents, and excessive moisture (which polycarbonate will
    absorb), can interfere with the ability of the laser to read the data.
    Contact of any foreign material with the polycarbonate substrate
    layer should be avoided.