CDs Or DVDs: Shield From The Storm

It's rare for me to write on the same general topic three times in a month, but recent disasters in the Gulf Coast have kept the subject of backing up data on the front burner. As millions of Americans can now testify, having access to our possessions – including precious data such as family photos – is not something we can take for granted.

Of course, computer data is trivial compared to human life but it's arguably as important as any of your physical possessions. Furniture can be replaced, but family photos, tax records, correspondence and all those other data files on your PC are irreplaceable unless they're backed up. This is especially important for photographs now that many people are using digital cameras. Unlike traditional photos, it's not hard to backup digital photos so there really is no reason not to be protected.

And, of course, you don't have to be a potential hurricane victim to be concerned about losing data. Everyone lives in a potential disaster area and even if that never happens, there is always the real possibility of your hard drive failing or data being destroyed as a result of a computer glitch, malicious software or user error.

CDs and DVDs

A simple and inexpensive solution is to copy your important data files to CDs or DVDs. One advantage of this strategy, according to David Bunzel, President of the Optical Storage Technology Association is that CDs and DVDs, while not impervious to damage, are less likely to fail in the case of water damage. Also, it's relatively easy to make an extra copy of a DVD or CD.

Keep one with your equipment and mail the other to a friend or relative – preferably out of town. I just backed up my thousands of family digital photos to two DVDs and mailed them to a friend of mine. I shutter at the thought, but if anything were to happen to my home, at least our precious photos would be safe. I don't live in hurricane country but California does have earthquakes and, of course, fires.

I'm also careful to maintain an off-premise backup of my financial data. Several years' worth of data from Quicken, Microsoft Money and other financial programs can easily be stored on a single writable CD. I've mailed a copy of mine to my accountant who is keeping it in my file.

Even if a CD or DVD is under water for an extended period, it is likely that they are still usable. OSTA recommends that you gently rinse the DVD or CD in warm water. If necessary, use mild detergent or eye-glass cleaner.

If you must rub the disc to remove debris, use a "soft dry lint-free cloth or camera lens tissue. Holding the disc by its outer edges or center hole, gently wipe outward from the center hub toward the outside edge of the disc (just like the spokes of a bicycle wheel). Do not wipe the disc using circular motions, as any scratches created will do the least damage if they cut across the track of marks and lands." The association warns not to use "vinyl record cleaners, lacquer thinner, gasoline, kerosene, benzene or other solvents, as these may damage the disc. "

Once you've cleaned a disc, it's important to copy that disc to another one that will then be in pristine condition.

Although it's nice to have a complete backup of your system, it's not essential that you backup your operating system and your software. They can be replaced – your data can't.

Most PCs today come with at least a CD writer (burner) if not a drive that can burn both CDs and DVDs. The advantage of DVDs over CDs is that they store a lot more data. A typical DVD writable disc can store 4.7 gigabytes as opposed to the 700 gigabytes that can be stored on a CD.

To put that into context, it's rare for a photograph taken on a consumer digital camera to be more than a megabyte – they're typically smaller. Even with a megabyte per picture, you could store 4,700 pictures on a single DVD. A single CD can store more than 700 photos.

Most Windows and Mac machines with a CD or DVD burner came with the necessary software. If not, Roxio's Easy Media Creator 7.5 ($75) does an excellent job of copy data to CDs and DVDs and it now comes with a robust PC backup program.

Blank CDs, when bought in bulk, cost as little as 30 cents each. You can also buy bank DVDs in bulk for as little as about 50 cents each but even if you just buy one, it will cost you as little as $1.50 which strikes me as cheap insurance.

With both CDs and DVDs there are at least two types of media: recordable (R) and re-writable (RW). Discs and drives labeled CD-R or DVD-R or DVD+R are recordable which means they can write once to a disc and after a disc has been created it can't be modified, added to or erased. RW means that the disk is re-writable which means it can be modified or erased.

For backup purposes, it's generally better to use the recordable (R) instead of the rewritable or RW format. The fact that a recordable disc can't be modified is actually a benefit because you don't have to worry about them being erased. Besides, the R discs are usually less expensive than rewritable ones and they can be read by more drives.

With DVDs there is another wrinkle. There are competing formats marked as either – or +. The good news is that most PCs these days come with a DVD burner that can handle both formats. If not, be sure to buy blank discs that are compatible with your burner.

The OSTA has these suggestions for the proper handling and cleaning of DVDs and CDs:

1. Handle discs carefully by the edges only.

2. Inspect the surface of the disc for damage or contamination, to see if it needs to be cleaned. Canned compressed air is excellent for removing dust.

3. If needed, rinse carefully in clean, warm water to remove any grit that could cause scratches when the disc is wiped.

4. If any debris or film remains that needs to be removed, clean gently with warm water and a mild detergent (e.g., dish-washing detergent), eyeglass cleaning solution, isopropyl alcohol or a commercially available CD/DVD cleaning solution.

5. Gently wipe dry with a lint-free, soft cotton cloth. Use a wiping motion moving from the center of the disc to the outside edge instead of wiping around the disc. If wiping does cause any scratch, an "inside to outside" scratch will cut across the data tracks around the disc instead of running along them and damaging additional data.

6. If any residue or film remains, wipe with alcohol and a soft cleaning wipe.

7. Remember to clean the case, too.

8. If a disc is still damp, store upright (on edge) to allow to air dry.

9. Insert thoroughly dry disc in appropriate disc drive to attempt to read data. If the disc isn't readable, try a different disc drive. Different drives have different optical qualities with varying thresholds of error correction ability.

10. Data on the majority of discs is likely to be readable after following these steps. For those discs that still cannot be read, additional information on disc handling and data recovery is available on OSTA's website in the data handling, storage and disposal sections of two white papers on recordable CDs and DVDs. For the applicable section in "Understanding CD-R and CD-RW" go to http://www.osta.org/technology/cdqa12.htm. For "Understanding Recordable and Rewritable DVD," the related section is located at http://www.osta.org/technology/dvdqa/dvdqa10.htm.

Of course, you can also back up to other media including tape or an external hard drive, but these are much more vulnerable to damage than optical media. The ideal solution is to backup via the Internet but that can be expensive. @Backup, the leading Internet backup firm, charges $495 a month for up to 250 megabytes and considerably more for larger amounts of storage.