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Life of the Disc |
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What's the life span of a CD / DVD. How long can you feel confident the data will be accessible anytime you need it. Is there a difference between a Movie / Music Disc or a disc you burn?
How many times can a CD-RW disc be rewritten?
As is the case with all optical storage media using phase change technology there is a limit to the number of times the recording layer in a CD-RW disc can be reliably switched between its crystalline and amorphous states. Currently, CD-RW discs can be rewritten approximately 1000 times.
What is the shelf life of unrecorded CD-R and CD-RW discs?
The unrecorded shelf life of a CD-R or CD-RW disc is conservatively estimated to be between 5 and 10 years.
How long will data recorded on CD-R and CD-RW discs remain readable?
The life span of a written disc depends upon a number of factors including such things as the intrinsic properties of the materials used in the disc’s construction, its manufactured quality, how well it is recorded and its physical handing and storage. As a result, the life span of a recorded disc is extremely difficult to estimate reliably. However, to calculate disc life spans within some practical timeframe blank media manufacturers do conduct accelerated age testing by subjecting samples of their discs to environments much beyond those experienced under normal storage conditions. Generally speaking, only the effects of varying temperature and humidity are considered. These test results are then used to predict how long a disc will remain readable under more normal storage conditions. Since questionable testing and measurement procedures can seriously impact upon and compromise these estimates several international standards have been developed which specify procedures to be used conducting accelerated testing and analyzing the resulting data from prerecorded (pressed) and recordable CDs. |
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