Salvaging Optical Disks, Floppy Disks, and Magnetic Tape

If any of these media contain critical or irreplacable files or recordings, you may wish to seek professional help with cleaning and data recovery. If you plan to seek professional assistance:

If it is already wet, keep it wet - do not try to dry it out.
If the disk or tape is wet and heavily-soiled, rinse in clean water. Do not rub. If dry and soiled, leave it alone and send to data recovery specialist.
Bag or wrap in anti-static (for tapes or other magnetic media) plastic. Keep it cool to prevent mold growth, but do not freeze. If mold has already started to grow, wear a respirator. Mold is a health hazard.
Get media to a data recovery specialist as soon as possible.

Information on professional data recovery.

If you wish to attempt recovery yourself:

Clean carefully following the instructions below.
Guard against exposing magnetic media to magnetic fields or static electricity. If you use a vacuum to remove dry particles, it must be an anti-static type of machine. Static electricity can erase tapes and magnetic media.
Copy to new media as soon as possible. Coatings on tapes or disks (both magnetic and optical) may be unstable and may continue to deterioriate.

CD/DVD Disks

Be careful not to scratch disk, especially the shiny non-label side or data may be lost.
Rinse dirty disk in clean water. Do not scrub. If dirt will not come off with rinsing, soak in mild detergent solution, then rinse.
Air dry label edge up in racks or label side down on a sheet of clean wax paper.
Dust and smudges can be cleaned with a soft lint-free cloth using light strokes from the outside edge toward center only.

Floppy disks, Zip Disks, Back-up Tape

If the data is valuable, seal in plastic and send to a data recovery specialist.
If you want to attempt recovery yourself, take disk out of enclosure. Rinse in fresh clean water. Dry on lint-free or microfiber cloth. Place in new enclosure.

Magnetic Tape

(Analog or digital - except old paper-backed tape)

If wet and dirty, do not let tapes dry out. Rinse as soon as possible in clean water to remove contaminants. If necessary tapes can stay wet for several days.
Avoid use of extreme heat or cold-both can damage tapes.

Open Reel Tapes

If covered with mud, or other contaminants-rinse in clean water.
If needed add a small amount of mild dishwashing detergent to the cleaning water.
Rinse in clean water.
Air dry vertically in racks.

Tape in Cassettes

If only case is wet or dirty, wipe clean.
If inside is contaminated, open cassette, remove tape reel and clean and dry as with open reel tape (note: there is serious risk of damaging the tape if cassette is disassembled - so do not try this unless you are comfortable with the mechanism and prepared to take the risk).

More information:

The National Archives has an excellent list of steps to take for lessening damage to magnetic tapes and media after a disaster. http://www.archives.gov/preservation/conservation/magnetic-media.html. The site also has information on conservation of film and paper.

VidiPax is a major magnetic media restoration company, phone 1.800.663.8434. a description of their process of mold removal from magnetic tape is at cool.conservation-us.org.

Care and Handling of CDs and DVDs: A Guide for Librarians and Archivists published by the Council on Library and Information Resources and the National Institute of Standards and Technology has information on cleaning, handling, and care of optical media. Chapter 5 on Conditions that Affect CDs and DVDs and Chapter 6 on Cleaning are the most useful in this context.