In the early ‘80s when the first CD-R disc was introduced manufacturers said the media had a data life in excess of 40 years. In the 90s when the first DVDR discs appeared on the scene producers proclaimed a data life of at least 100 years. Throughout that time and even today the press will “discover” that the media is susceptible to CD or DVD rot that will eat your information – audio, video or data – in as little as two years after it is written.

Because CD and DVD media – in 2003 more than 7,150 million CD-R discs and more than 400 million DVDR discs were made and sold -- is used to archive nearly everything today it does make you worry. Especially when these discs are the only place you have precious, irreplaceable family memories – photos and movies – as well as vital family, personal and company data/documents.

So where does the truth lie? Somewhere across the complete spectrum.

Most people who burn a disc without producing a coaster believe they have quality media. Unfortunately that only tells you the disc will be compatible (able to be played) in the vast majority of CD or DVD players. More importantly all better quality CD and DVD burners include technology called overburn/underburn protection making coaster production a thing of the past.

Test Options
There are only two foolproof ways of proving the data life of the discs you use:
1. write a few CD or DVDRs, then wait about 25-50 years and check if they still hold the correct data
2. Use a CD/DVD analyzer that is specially designed to retrieve very accurate information about your media and your data after accelerated aging in test chambers where the discs are subjected to excessive temperature and humidity tests

The first is impractical. However, we have seen some of the first discs produced and written to in Japan and yes the data is still intact. The second provides only theoretical limits and doesn’t take into consideration how you use, handle and store the media. However, assuming proper handling, chart D illustrates how temperature and humidity can affect the data life of quality media.

Between the CD-R discs produced in the early 80s to today’s double layer DVD+R discs and throughout the brief optical industry there has been considerable progress in write performance, capacity, quality and obviously price.

Following the test procedures of the International Standards Organization (ISO) quality media manufacturers have been able to document data life-spans ranging from 50-200 years. But keep in mind there are wide differences between low budget media operations and quality media firms. In addition variations in manufacturing methods, materials and processes/procedures can dramatically effect the data life of the media you use.

Or as auto manufacturers say, “your mileage may vary.”

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