beegee
2004-04-05, 12:28 AM
Is Your CD Data Storage Safe?
Have CD-Rs become one of your staple data storage mediums? If so, recent information suggests that you better not take them for granted as a permanent storage solution. At the very least, should check your oldest CDs to make sure that they are not falling prey to some common problems with long-term data stability.
Fred Langa, in an InformationWeek article www.informationweek.com called “Time to Check Your CDRs (November 3, 2003), says that while conventional wisdom and testing suggested that CD-R data storage ranged from 10 years for the cheapest brand CDs to as much as a century for the premium rewritable disks, current studies suggest that issues can arise to cut this lifespan dramatically. These predicted stable age ranges were based on testing the dye layers of a CD. The dye is where the data is actually stored as well as giving it its characteristic color (e.g. blue, silver, gold).
Please refer to the June 2001 article on “Construction and Formatting of CDs” for more on this issue.
Last year reports from the Dutch PCActive magazine sent shivers through the digital world when it suggested that some CDs may fail in as little as two years. Such a steep drop in age seems a bit hard to believe in normal storage conditions but it has caused many users to scurry back to check their CD archives.
What Langa reports, based on his reader’s anecdotal evidence, is that if you do find any problems with your data storage, it is likely to have a “Failure Pattern.” That is to say, one typical characteristic is shared by all of the CDs that have data reading problems. Langa recommends CD Speed as a good testing tool for CD readability and which can be downloaded at www.cdspeed2000.com
Some of the common “Failure Pattern” issues that they report are as follows:
* No-name CD-R blanks bought on clearance or on sale;
* Problems with a particular utility backup software or routine used;
* Problems with a particular dye color (one cited silver with light green coating);
* Problems with hand labeled CDs using ballpoint pens or other sharp writing instruments.
* Problems with a particular glue-on paper label from a label-maker kit;
* Problems with unprotected loose storage of disks (e.g. in a drawer);
* Problems with excessive heat or humidity (it is particularly crucial to keep CDs dry);
Additionally, the following warning information comes from another excellent resource on CD storage, the Optical Storage Technology Association <www.osta.org> (Technology/CD-R/RW
FAQs).
“Full surface” or “donut-style” labels are preferable to partial stickers but be aware that any adhesive label can potentially upset the balance of a disc when playing back, especially at high speeds, causing excessive noise, vibration and data retrieval problems. Heat, humidity, handling and the passage of time can also compromise the stability of adhesive labels causing separation from the disc surface and even interfere with the drive. Sticky labels may not be the best choice when archiving important data as some types of label adhesives can react with and compromise the disc over time. Remember too that, once applied, labels should never be removed or repositioned. Even smoothing air bubbles can concentrate physical stresses in a small area and delaminate the disc.”
In any case, if you have important data storage on CDs that is now over 2 years old, its highly recommend that you do some type of systematic testing at this point to see if you can turn up any failure patterns in your own archive before it is too late to do something about it. It reminds me also of the wisdom of the old favorite adage of “two mediums, two locations” being your best bet to preserve your data — no matter the technology, no matter the time. !
Have CD-Rs become one of your staple data storage mediums? If so, recent information suggests that you better not take them for granted as a permanent storage solution. At the very least, should check your oldest CDs to make sure that they are not falling prey to some common problems with long-term data stability.
Fred Langa, in an InformationWeek article www.informationweek.com called “Time to Check Your CDRs (November 3, 2003), says that while conventional wisdom and testing suggested that CD-R data storage ranged from 10 years for the cheapest brand CDs to as much as a century for the premium rewritable disks, current studies suggest that issues can arise to cut this lifespan dramatically. These predicted stable age ranges were based on testing the dye layers of a CD. The dye is where the data is actually stored as well as giving it its characteristic color (e.g. blue, silver, gold).
Please refer to the June 2001 article on “Construction and Formatting of CDs” for more on this issue.
Last year reports from the Dutch PCActive magazine sent shivers through the digital world when it suggested that some CDs may fail in as little as two years. Such a steep drop in age seems a bit hard to believe in normal storage conditions but it has caused many users to scurry back to check their CD archives.
What Langa reports, based on his reader’s anecdotal evidence, is that if you do find any problems with your data storage, it is likely to have a “Failure Pattern.” That is to say, one typical characteristic is shared by all of the CDs that have data reading problems. Langa recommends CD Speed as a good testing tool for CD readability and which can be downloaded at www.cdspeed2000.com
Some of the common “Failure Pattern” issues that they report are as follows:
* No-name CD-R blanks bought on clearance or on sale;
* Problems with a particular utility backup software or routine used;
* Problems with a particular dye color (one cited silver with light green coating);
* Problems with hand labeled CDs using ballpoint pens or other sharp writing instruments.
* Problems with a particular glue-on paper label from a label-maker kit;
* Problems with unprotected loose storage of disks (e.g. in a drawer);
* Problems with excessive heat or humidity (it is particularly crucial to keep CDs dry);
Additionally, the following warning information comes from another excellent resource on CD storage, the Optical Storage Technology Association <www.osta.org> (Technology/CD-R/RW
FAQs).
“Full surface” or “donut-style” labels are preferable to partial stickers but be aware that any adhesive label can potentially upset the balance of a disc when playing back, especially at high speeds, causing excessive noise, vibration and data retrieval problems. Heat, humidity, handling and the passage of time can also compromise the stability of adhesive labels causing separation from the disc surface and even interfere with the drive. Sticky labels may not be the best choice when archiving important data as some types of label adhesives can react with and compromise the disc over time. Remember too that, once applied, labels should never be removed or repositioned. Even smoothing air bubbles can concentrate physical stresses in a small area and delaminate the disc.”
In any case, if you have important data storage on CDs that is now over 2 years old, its highly recommend that you do some type of systematic testing at this point to see if you can turn up any failure patterns in your own archive before it is too late to do something about it. It reminds me also of the wisdom of the old favorite adage of “two mediums, two locations” being your best bet to preserve your data — no matter the technology, no matter the time. !