5. Safeguarding the information

a. By preservation of the carrier

Although the life of most audio carriers cannot be extended indefinitely, efforts must be made to preserve carriers in useable condition for as long as is feasible. Preservation requires storage in an environment suited to the purpose, separating primary and secondary information sources where necessary and possible, and performing routine maintenance and cleaning as needed. Maintenance also includes the regular checking of test tones, if available, on analogue carriers and of the data integrity of digital carriers. In addition, the equipment used for handling and replay must meet the physical requirements of the carriers. Preservation includes minimising the use of originals/archival copies by making access copies available.

b. By subsequent copying of the information

Because the life expectancy of carriers and the availability of hardware is limited, the preservation of the document in the long term can only be achieved by copying the contents to new carriers/systems when it becomes necessary.

In the analogue domain, the primary information suffers an increase in degradation each time it is copied. Only the digital domain offers the possibility of lossless copying when refreshing or migrating recordings (cf paragraph 12). For the long-term preservation of the primary information contained on an analogue carrier it is necessary, therefore, to first transfer it to the digital domain.

Removing the primary information from the original carrier raises the question of future authentication of the sound. Future users, for the reasons given in this document, may only have access to the primary information of a sound document in the form of a copy on a new carrier/system. Once carrier decay or system obsolescence makes access to the primary information of a sound document only possible by use of a copy of the original carrier, the importance of adequate secondary information increases. Archives need, therefore, to record in a systematic manner the relevant secondary information contained in the original document and to make this information accessible together with the copy of the primary information. By this means, future users can be sure of the authenticity of the primary data.