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Preventive Conservation and Digital Preservation Requirements for Category A Designation – Audiovisual Collections (Class 9 Objects)

Marianne Breault

Disclaimer

The information in this document is based on the current understanding of the issues presented. It does not necessarily apply in all situations, nor do any represented activities ensure complete protection as described. Although reasonable efforts have been made to ensure that the information is accurate and up to date, the publisher, Canadian Conservation Institute (CCI), does not provide any guarantee with respect to this information, nor does it assume any liability for any loss, claim or demand arising directly or indirectly from any use of or reliance upon the information. CCI does not endorse or make any representations about any products, services or materials detailed in this document or on external websites referenced in this document; these products, services or materials are, therefore, used at your own risk.

Alternative formats

  • Download as an Excel spreadsheet (60 MB) a version similar to the appendix: Checklist for the preservation of audiovisual collections. Please note that the Excel version includes the preventive conservation and digital preservation requirements set out in the Designation of Institutions and Public Authorities Program for Class 9 (audiovisual collections).

Table of contents

List of abbreviations
AIP
archival information package
CCI
Canadian Conservation Institute
DIP
Dissemination Information Package
ISO
International Organization for Standardization
LTO
Linear Tape-Open
OAIS
Open Archival Information System
RAID
redundant array of independent disks
RH
relative humidity
SSD
solid-state disks
USB
universal serial bus

Introduction

This document outlines the preventive conservation and digital preservation requirements that must be met in order to qualify for Category A designation under the Designation of Institutions and Public Authorities Program. More specifically, it concerns audiovisual collections (Class 9) for which an application for certification will eventually be made to the Canadian Cultural Property Export Review Board. This document focuses on the objectives to be achieved to ensure that audiovisual collections can be properly preserved over the long term and made accessible to the public.

The term “audiovisual collections” refers to a set of works, archived or not, which are made up of moving images and/or recorded sounds and generally require the use of a machine to play. Audiovisual collections encompass a wide variety of technologies and formats, both analog and digital, and require care distinct from that given to other types of collections to ensure their long-term preservation and accessibility. For this reason, Class 9 has special requirements in addition to those described in the Application Guide for the Designation of Institutions and Public Authorities.

The assessment for Class 9 objects includes two sections:

It is now recognized that storing and conserving physical carriers does not guarantee the longevity of content. Migration to digital formats is generally essential to ensure sustainable access to collections. To obtain Category A designation for Class 9, institutions must demonstrate their ability to:

It is important to note that there are many ways to achieve these preservation objectives, all of which are specific to each institution, mandate and operating context. The examples in this document are not exhaustive. Furthermore, this document does not cover all aspects of audiovisual collection management, such as reproduction rights.

After consulting this document and the checklist, institutions are invited to contact the Designation of Institutions and Public Authorities Program for further information on this program, or to discuss their specific project.

Analog audiovisual collections

Description of analog collections

Analog audiovisual documents are recorded on a variety of physical carriers, most of which are made of flexible plastic. Many of them degrade rapidly at room temperature. Cellulose nitrate- or acetate-based films, as well as dyes on any type of carrier, are particularly chemically unstable.

Institutions should keep an up-to-date inventory of these materials in their collection in order to determine needs and plan conservation. As a minimum, institutions should be able to provide information on the type and (approximate) number of analog audiovisual documents in their collection, particularly those that are chemically unstable. The audiovisual documents for which institutions must provide this information are as follows:

Consult the Further reading section for resources on identifying materials in analog audiovisual collections.

Storage at low temperature

Generally, low-temperature storage slows down the degradation of audiovisual collections on plastic carriers. To qualify for Category A designation for Class 9, applicants must have at least one low-temperature storage space. Additional space is also needed to allow for collection growth.

Low-temperature storage spaces can be of different kinds. Depending on the size of the collection and the institution’s resources, these spaces may include freezers, refrigerators or air-conditioned rooms (cold rooms).

A storage space is considered low temperature when the temperature is maintained below 16ºC, as opposed to storage maintained at room temperature. There are three categories of low-temperature storage, depending on the temperature maintained:

Table 1 shows the possible temperature ranges for storage and whether they are recommended for the materials most commonly found in analog audiovisual collections. These ranges are based on ISO standards (Adelstein 2009), which assume relative humidity (RH) control between 30% and 50%, daily temperature fluctuations of less than ±2°C and RH fluctuations of less than ±10%. Although meeting these conditions for long-term storage of individual materials is not required to obtain Category A designation for Class 9, it is recommended that they be observed to increase the longevity of analog audiovisual collections.

Table 1: storage temperature recommendations for different types of materials
Storage temperature Nitrate Acetate (black and white) Acetate (colour and degraded materials) Polyester (black and white) Polyester (colour) Magnetic tapes (acetate) Magnetic tapes (polyester)
Room (16°C to 23°C) No No No Fair No No No
Cool (8°C to 16°C) No No No Good No Fair Good
Cold (0°C to 8°C) Good Good Good Very good Good Good Fair
Frozen (-20°C to 0°C) Very good Very good Very good Very good Very good No No

Assessors recognize that it is not always possible to keep all analog audiovisual collections in low-temperature storage. The selection of carriers to be placed in storage can be made according to criteria determined by the institution. These criteria may include:

These criteria should be discussed among various parties within the institution and set out in a policy.

Climate monitoring

Sensors should be used to measure temperature and RH in low-temperature storage spaces. Alarms or other means of continuous monitoring should be in place to detect any significant deviation from temperature or RH set points and to intervene quickly if necessary.

Institutions must provide temperature and RH graphs, covering a 12-month period, for each room or area where analog audiovisual collections are stored. Assessors expect any anomalies to be identified and justified, with details of any corrective action taken.

Packaging of analog audiovisual collections

Analog audiovisual collections in low-temperature storage should be packaged to protect them from the risks associated with handling, condensation and pollutants. Packaging is expected to vary according to the temperature and type of environmental control in the storage space, the nature of the document and the use of the collection. Applicants will be asked to provide photographs illustrating the ways in which documents are commonly packaged in the collection.

Document retrieval procedure

Institutions must follow a written procedure for retrieving documents placed in low-temperature storage. The procedure must include a period of acclimatization if the difference in temperature and RH between the storage space and the reading room presents a risk of condensation for the object. Condensation may form on an unpackaged item coming out of a storage space if the temperature of the storage space is below the dew point in the room to which the item is brought.

Playback and digitization

Playback of analog audiovisual recordings presents challenges associated with the technological obsolescence of playback devices. Institutions managing a large analog audiovisual collection should have playback equipment for at least 50% of their collection, along with the human and material resources needed to ensure their smooth operation. Failing that, assessors expect institutions to explain clearly how they will access the content of certified cultural property, while managing the risks associated with playback (for example, by pooling equipment and outsourcing to external suppliers).

Digitization of analog audiovisual recordings is generally the preferred way to ensure sustainable access to content. Preservation copies resulting from digitization should be subject to a digital preservation strategy similar to that used for born-digital collections. In addition, the strategy adopted for preservation copies can be integrated with the strategy for born-digital collections.

Playback and digitization pose risks, as they can damage analog documents to the point of rendering them unplayable. These actions must therefore be carried out by specialists, who may be staff of the institution or of a specialized third-party company. To find out more about using external services, consult “Outsourcing the Digitization” in Technical Bulletin 31 The Digitization of VHS Videotapes.

Access to analog audiovisual collections

In general, access copies should be created to ensure public access to analog audiovisual collections. Original carriers of certified cultural property should not be used on a regular basis to ensure access. Some institutions, however, may provide policies and procedures explaining the context in which original analog documents can be used and how risks are managed.

Digital audiovisual collections

An institution recognized as a trustworthy digital repository automatically qualifies for the digital component of the assessment. Trustworthy digital repositories are audited and certified to ISO 16363:2012. This certification is not required for Category A designation, but it does demonstrate that the institution meets the highest standards of digital preservation.

Digital preservation policy and plan

Institutions will need to provide a written digital preservation policy, plan or strategy that details their commitment to digital preservation and their understanding of the associated issues. To learn more about the importance and development of these documents, consult Digital Preservation Plan Framework for Cultural Heritage Institutions and Digital Preservation Policy Framework: Development Guideline Version 2.1.

Institutions using the Open Archival Information System (OAIS; ISO 14721:2012) reference model should make explicit reference to it in their policy. The OAIS standard is a reference model that defines the basic concepts and vocabulary of digital archiving. It does not propose any specific implementation. Adherence to this standard is encouraged but not mandatory for designation.

Storage of digital audiovisual collections

Preservation copies

When institutions acquire digital assets, they may be found on a variety of physical carriers that may be obsolete or likely to become obsolete, which can compromise access to digital assets. To ensure their long-term conservation and facilitate digital preservation activities, institutions must create preservation copies (formerly known as “master copies”) for each digital asset entering the collection and add them to the chosen storage solution. Please note that, except in special cases, preservation of the original physical carriers is not required to obtain the designation.

A preservation copy is a file or group of files that combines the original content of a digital asset and the information associated with it in the most faithful, high-quality version possible. It is accompanied by metadata (including file creation date, author, copyright and access rights). A preservation copy generally shows little or no change from the original. For institutions using the OAIS reference model, the archival information package (AIP) will be considered the preservation copy for the purposes of assessment for the designation program.

To qualify for designation, a minimum of two preservation copies is required per digital asset, but ideally a third copy should also be maintained. One of these copies should be stored off site or on a cloud server to reduce the risk of loss in the event of a disaster. If the same type of physical carrier is used for both copies, it is recommended to use a different brand to reduce the risk of failure.

Storage types

The storage system chosen by the institution is expected to vary according to its organizational context, size and resources. The type(s) of storage should be stable and resilient.

Different types of storage are possible:

The following are examples of acceptable physical carriers:

Note that the use of a cloud storage service is acceptable only when combined with another storage mode, in order to meet the requirement of maintaining two preservation copies in two locations. While some vendors offer complete digital collection archiving solutions that include geographic redundancy, the institution must still maintain an independent second copy, unless the vendor operates a certified, ISO 16363:2014-compliant trustworthy digital repository.

Storage conditions

Because technology continues to evolve, physical carriers are generally not intended to be retained for long periods. For this reason, temperature and RH readings are not required for digital audiovisual collections. The main objective is to avoid extremes. In general, it is recommended that the temperature be kept between 8°C and 23°C and the RH between 20% and 50%. Large, rapid fluctuations in temperature and RH should be avoided. Carriers should also be protected from pollutants.

Digital preservation practices

Institutions must demonstrate that their digital preservation practices enable them to manage the risks associated with technological obsolescence and degradation of the physical carriers on which collections are stored, in order to guarantee long-term access to content. These practices should apply to all preservation copies maintained by the institution. As a minimum, the institution must commit to ensuring that certified cultural properties benefit from the best digital preservation practices it can offer.

Maintenance and refreshing of physical carriers

As no physical carrier is immune to obsolescence or failure, preservation copies need to be proactively transferred to a new carrier at regular intervals, or in some cases recopied onto the same carrier. This is known as “refreshing.” Inspection and maintenance of equipment required to read carriers are also recommended.

Generally, the following practices can ensure the conservation of digital audiovisual collections:

Whether these practices are required to obtain Category A designation for Class 9 will depend on the overall digital preservation measures implemented by the institution. For example, for institutions that have chosen LTO tapes or hard drives as their main storage solution, periodic media refreshing is essential. However, for institutions using redundant systems (mirrored systems, parity systems or similar technology, usually hard drives or SSDs), refreshing of preservation copies may not be required.

It is recommended that the carrier on which preservation copies are stored be inspected at regular intervals. This can include physical inspection of the carrier and verification of access to files. Regular inspection can enable early detection of risks of loss of access to data due to deterioration of the physical carrier. If the storage conditions are adequate and the content is refreshed at regular intervals (as mentioned above), the risk of losing content due to carrier deterioration is reduced.

Fixity and data integrity

It is important to ensure the integrity of digital audiovisual collections. When digital content is extracted from its original carrier, the use of write blockers is recommended to prevent any modification of the content.

The institution should generate a checksum for all digital assets. It is recommended that it be checked at regular intervals (for example, every year for magnetic tape media and every six months for disk systems). This practice, which can be automated, makes it possible to detect whether the content of a file has been modified, intentionally or otherwise.

Backups should be made at regular intervals if data is online or networked. This measure may, however, be less suitable for offline storage systems (for example, external hard drives and archival-quality optical discs).

File formats

Rigorous management of file formats is essential to ensure long-term access to digital audiovisual content. It is necessary to keep an up-to-date inventory of the file formats present in the collection. If the institution keeps a digital asset register, it can store information on file formats there.

A technology watch is recommended to identify file formats at risk of obsolescence. To guarantee access to content, assessors expect institutions to migrate preservation copies to new formats if the previous format becomes obsolete. Where possible, migrating digital assets to internationally recognized standard formats prior to ingesting them in the archiving system can facilitate digital preservation actions, both for digitized and born-digital documents. National Heritage Digitization Strategy – Digital Preservation File Format Recommendations can be consulted to check the suitability of the formats used.

Institutions should ensure that they have all the software and operating programs needed to play the file formats in the collection and should keep them up to date. This may be original software or software that is part of an emulation system.

Metadata

The institution should record and preserve descriptive, preservation and administrative metadata to identify content and facilitate the preservation of digital assets. Metadata can also include information on copyright and reproduction rights or any other access restrictions, audit trails on digital asset management and information on the digitization process, where applicable.

File organization

The institution should use a standardized and uniform system for assigning file names. In addition, it is recommended that directories be organized according to a standardized structure (for example, chronological order, project or file format) to facilitate access to collections.

Safety measures

Antivirus software must be used to preserve the integrity of digital assets. Infected content should be quarantined. The use of a firewall is an additional security measure that can be employed, especially if collections are stored on a network.

Preservation copies should be stored securely. Depending on the storage method chosen, this may involve physical measures such as a secure room, IT measures such as authentication procedures and the use of profiles with more or less restricted access, or a combination of both types of measures. However, using encryption techniques or passwords specific to each preservation copy is not recommended, as these measures may compromise access to the files.

Access to digital collections

To reduce the risk of theft or degradation, preservation copies must not be taken out of storage. Instead, access to digital audiovisual collections must be provided through access copies. An access copy (also known as a “working copy” or “reference copy”) is derived from a preservation copy, so that users can access or modify digital audiovisual content without putting the preservation copy at risk. An access copy is generally in a different format or of lower quality than the original. For institutions using the OAIS reference model, this corresponds to the Dissemination Information Package (DIP) for the purposes of assessment for the designation program.

Acknowledgements

The author would like to thank Ern Bieman of the Canadian Heritage Information Network for contributing to this document.

Appendix: Checklist for the preservation of audiovisual collections

This list summarizes the preventive conservation and digital preservation measures recommended in this document. To obtain a list of measures required for Category A designation for Class 9, consult the box on the alternative format.

Analog audiovisual collections

Digital audiovisual collections

Glossary

access copy

A copy derived from a preservation copy, which allows users to modify or access the information without putting the preservation copy at risk. It is usually in a different or inferior-quality format. Also called “working copy” or “reference copy.”

archival information package (AIP)

An archival information package consists of the content to be preserved as well as any related information required for its preservation, which is kept within an OAIS-compliant software.

checksum

A small amount of data generated by applying a function to a larger block of data. In the context of digital preservation, checksums are used to detect inadvertent changes to file contents.

data integrity

“Property of data that is not subject to accidental or unauthorized alteration during processing, transmission or storage” (translation). (Office québécois de la langue française 2024)

digital asset

In the context of this document, a general term for digital audiovisual documents. It includes born-digital documents for which there has never been an analog equivalent and for which there are no plans to create one, as well as digital substitutes created following the digitization of analog recordings.

digitization

The process of converting an analog signal into a digital format. The resulting digital copy will then be classified as a digital asset and subject to digital preservation processes.

file format

Standard way of encoding information for storage in a computer file. The file format tells the computer how to display, print, process and save information.

fixity

The assurance that the bits composing a digital asset have remained unchanged.

migration

Conversion of digital assets from one physical carrier or file format to another to avoid obsolescence and ensure access to content.

obsolescence

Loss of the ability to access the content of a document due to the industry abandonment of the file format, hardware or software required to access it.

Open Archival Information System (OAIS)

The OAIS standard is a reference model that defines the basic concepts and vocabulary of digital archiving. It does not propose any specific implementation.

original carrier

The original physical carrier on which the digital document is provided by the donor, artist or vendor at the time of acquisition (for example, compact disks, floppy disks, USB sticks). The original carrier is not necessarily retained once the document is added to the institution’s storage system.

physical carrier

The physical object (removable or not) on which a digital resource is stored, for example a hard drive, a floppy disk, an optical disc or LTO tape.

preservation copy

A copy generated by institutions for long-term preservation. Formerly known as a “master copy,” a preservation copy is a file or group of files that combines the original content and information associated with it in the most faithful, high-quality version possible.

refreshing

The migration of data onto a newer version of the physical carrier so that degradation of the older carrier does not pose a risk of data loss. In the case of flash memory media, refreshing can be achieved by copying the data to the same carrier.

storage system

A system designed to store and organize digital data in a secure and accessible way.

write blocker

A tool that prevents a computer system from modifying any digital asset when playing or copying it. Hardware write blockers are generally considered more reliable.

Bibliography

Adelstein, P. Z. Image Permanence Institute Media Storage Quick Reference, 2nd edition. Rochester, NY: Image Permanence Institute, 2009.

Bieman, E. Digital Preservation Plan Framework for Cultural Heritage Institutions, revised version. Ottawa, ON: Canadian Heritage Information Network, 2021.

Hill, G. Care of Plastic Film-based Negative Collections. Technical Bulletin 35. Ottawa, ON: Canadian Conservation Institute, 2020.

Iraci, J. The Digitization of VHS Videotapes. Technical Bulletin 31, revised version. Ottawa, ON: Canadian Conservation Institute, 2020.

Iraci, J. Electronic media collections care for small museums and archives. Ottawa, ON: Canadian Conservation Institute, 2020.

Library and Archives Canada. Library and Archives Canada Audiovisual Migration Strategy. Government of Canada, [n.p.], April 2024.

McGovern, N. Y. Digital Preservation Policy Framework: Development Guideline Version 2.1. Canadian Heritage Information Network, n.d. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

Office québécois de la langue française, Grand dictionnaire terminologique. Government of Quebec, [n.p.], 2024.

Further reading and resources

Bieman, E. Capture Your Collections: A Guide for Managers Who Are Planning and Implementing Digitization Projects, revised version. Ottawa, ON: Canadian Heritage Information Network, 2020.

Bieman, E. A Museum’s How-to Guide for Digitizing Audio. Ottawa, ON: Canadian Heritage Information Network, 2024.

Bieman, E., and W. Vinh-Doyle. National Heritage Digitization Strategy – Digital Preservation File Format Recommendations. Ottawa, ON: Canadian Heritage Information Network, 2019.

Canadian Conservation Institute. Electronic media, 2020.

Canadian Heritage Information Network. Digital Preservation Toolkit. Ottawa, ON: Canadian Heritage Information Network, n.d.

Digital Preservation Coalition. Digital Preservation Handbook, 2024.

Image Permanence Institute. FilmCare.org. [N.p.]: 2024.

International Organization for Standardization. ISO 10356:1996, Cinematography — Storage and handling of nitrate-base motion-picture films. Geneva, Switzerland: International Organization for Standardization, 1996.

International Organization for Standardization. ISO 18923:2000, Imaging materials — Polyester-base magnetic tape — Storage practices. Geneva, Switzerland: International Organization for Standardization, 2000.

International Organization for Standardization. ISO 18911:2010, Imaging materials — Processed safety photographic films — Storage practices. Geneva, Switzerland: International Organization for Standardization, 2010.

International Organization for Standardization. ISO 16363:2012, Space data and information transfer systems — Audit and certification of trustworthy digital repositories. Geneva, Switzerland: International Organization for Standardization, 2012.

International Organization for Standardization. ISO 14721:2012, Space data and information transfer systems — Open archival information system (OAIS) — Reference model. Geneva, Switzerland: International Organization for Standardization, 2012.

Iraci, J. Longevity of Recordable CDs, DVDs and Blu-rays, revised version. CCI Notes 19/1. Ottawa, ON: Canadian Conservation Institute, 2020.

Iraci, J. Caring for audio, video and data recording media. Preventive conservation guidelines for collections. Ottawa, ON: Canadian Conservation Institute, 2020.

Matters in Media Art, 2015.

National Digital Stewardship Alliance. Levels of Digital Preservation. 2024

National, Provincial and Territorial Archivists Conference Audiovisual Preservation Working Group, and National Heritage Digitization Strategy Steering Committee. Recommendations on Preservation Files for Use in the Digitization of Analog Audio and Video Recordings and Motion Picture Films (PDF format). [N.p.]: [n.p.], 2018.

Northeast Document Conservation Center. Fundamentals of AV Preservation, online course. 2022.

© Government of Canada, Canadian Conservation Institute, 2025

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