Your CD Collection is Dying a Slow Death

Got any CD's that will still play? Better check them, now. Back in the early '90s when the first CD-R disc was introduced manufacturers said the media had a data life in excess of 40 years. They lied. In the late 90's when the first DVDR discs appeared on the scene producers proclaimed a data life of at least 100 years. They lied too. 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.

All this is in the news today because there's a story going around about the lead scientist and chief of preservation research and testing at the Library of Congress, Ms. Fenella France, is trying to figure out how CD's age so that we can better understand how to save them. But it's a tricky business, in large part because manufacturers have changed their processes over the years and even CD's made by the same company in the same year and wrapped in identical packaging might have totally different lifespans. 'We're trying to predict, in terms of collections, which of the types of CD's are the discs most at risk,' says France. 'The problem is, different manufacturers have different formulations so it's quite complex in trying to figure out what exactly is happening because they've changed the formulation along the way and it's proprietary information.' 

There are all kinds of forces that accelerate CD aging in real time. Eventually, many discs show signs of edge rot, which happens as oxygen seeps through a disc's layers. Some CD's begin a deterioration process called bronzing, which is corrosion that worsens with exposure to various pollutants. The lasers in devices used to burn or even play a CD can also affect its longevity. 'The ubiquity of a once dominant media is again receding. Like most of the technology we leave behind, CD's are are being forgotten slowly,' concludes France. 'We stop using old formats little by little. They stop working. We stop replacing them. And, before long, they're gone.'"

What to do with your treasured collection? The CD's you have that were professionally manufactured are probably OK, at least right now, but you should make digital copies and store them. The best place? In the cloud. There are multiple sites that keep your precious music and data safe for free or a small fee. But if you've got CD's or DVDs that were written on your computer, recordable CD's, get to work copying them now before they stop playing completely, because they're more susceptible to damage.

What to do with the old CD's or DVDs after you've copied everything? You can donate CD's to be tested for aging characteristics by emailing the Center for the Library's Analytical Science Samples.
http://www.loc.gov/preservation/scientists/projects/class.html.