Looking after digital storage

Digital and electronic technology is constantly changing as tried and tested products are updated and replaced. Given the inevitable obsolescence of many digital and electronic products, the following guidance relates to the care, handling and storage of some of the most commonly used media to ensure long-term access to the information they contain.

Optical Disks
The most common form of optical disk is the Compact Disc, available in read-only (CD-Rom), recordable (CD-R) and rewriteable (CD-RW) formats. Recordable CDs include a dye layer and a metallic and reflective layer on a clear polycarbonate substrate. CD-Rs with a gold reflective layer have a longer life span and are the most suitable for long-term preservation. DVDs (Digital Versatile Discs) come in a similar range of formats as the CD.

The Blu-Ray DVD format was developed for high-definition video. It offers more than five times the storage capacity of traditional DVDs with a dual-layer disc able to hold up to 50GB. Blu-Ray DVD players will also play DVDs and CDs, but ordinary players will not play Blu-Ray DVD discs.

Memory Sticks
This is an extremely portable system of storing information that is also more robust than other storage devices. They allow large amounts of data to be stored, and access to the data can be quite fast. It is important to check that the computer being used is not infected with a potentially harmful virus, which could transfer itself onto the memory stick, and then onto another computer.

Photo storage cards
Used for storing images from a digital camera. Some formats like Fuji's Smart Media format are already obsolete with the SD (Secure Digital) format becoming the most widely used. All photo storage cards should be handled carefully, kept dry and clean, and not left for any long periods of time in the card reader as the heat can shorten their lifespan.

What can go wrong
The supporting hardware necessary to read digital and electronic media usually has a shorter life than the media itself. Nevertheless, electronic and digital media is susceptible to damage both through mishandling and inappropriate storage conditions and by storing media in proximity to electromagnetic fields.

Protecting your own collection

General guidance

• Avoid touching the upper surfaces of CD Roms and DVDs, only handle them at the extreme edges or the centre hole as they scratch easily. Salt and grease films from fingers are equally destructive.
• Protect electronic and digital media from liquids, dust, extreme heat and direct sunlight.
• Store electronic and digital media vertically in purpose-made storage containers. Rigid containers are preferable to sleeves.
• Clean drives routinely to prevent damage to the media; do not keep media in drives for longer than necessary.
• Apply labels only to the areas recommended by the manufacturer.
• Clean dusty or dirty CDs and DVD's with a soft dry cloth, on the underside only - never clean the label side.

Copying to new formats
To ensure long-term access to your own electronic or digital collections it is recommended that the data is copied from its existing format to a more modern format. For example thousands of 3.5" floppy disks can be copied onto a single DVD.