Overview
ISO 18934:2011 provides international guidelines for the storage environment of archives containing multiple types of imaging materials and recording media. Developed by the International Organization for Standardization (ISO), this standard addresses the practical challenge of storing diverse media-such as photographic film, prints, magnetic tapes, and optical discs-under environmental conditions that help preserve their longevity. ISO 18934 emphasizes the importance of following corresponding ISO storage standards for individual media types whenever possible, but it recognizes that mixed-media archives often necessitate environmental compromises for practical and economic reasons.
This standard describes four temperature and humidity macro-environments-room, cool, cold, and subzero-suitable for long-term archival storage. While it does not cover traditional paper collections, ISO 18934 does include guidelines for nitrate-base photographic films, acknowledging their common presence in mixed-media archives and specific handling needs.
Key Topics
- Macro-environment Guidelines: Focuses on temperature and relative humidity conditions on a large scale (archive or storage room), rather than micro-climates within individual enclosures.
- Temperature and Humidity Ranges: Suggests four main temperature categories-room (16°C to 23°C), cool (8°C to 16°C), cold (0°C to 8°C), and subzero (–20°C to 0°C)-all with relative humidity (RH) ranges generally between 30% and 50%.
- Media-Specific Considerations: Provides summary tables comparing optimal storage environments for different media, such as black-and-white and color photographic film, magnetic tape, and optical discs.
- Material Stability and Life Expectancy: Describes how temperature and humidity control affect the predicted life expectancy (LE) of archival materials, noting that even incremental improvements to storage conditions can benefit preservation.
- Temperature and Humidity Cycling: Recommends limiting fluctuations, keeping daily variation within ±3°C and ±5% RH, to reduce risks of physical or chemical damage to materials.
- Special Requirements for Nitrate Films: Includes specific references to national standards for safely storing nitrate-base films, which pose fire and contamination risks.
Applications
ISO 18934:2011 is vital for:
- Archives and Libraries: Institutions preserving photographic, audio, and video materials in a single facility can use these guidelines to optimize environmental conditions when it is not feasible to store each media type separately.
- Museums and Heritage Organizations: Ensures the long-term stability of valuable and irreplaceable mixed-media collections by recommending suitable storage conditions that extend material life expectancy.
- Record Managers and Preservation Specialists: Offers a structured approach to selecting storage environments, balancing resource constraints with optimal preservation outcomes for multiple media types.
- Facilities Managers: Provides a framework for developing climate control strategies in archives that minimize detrimental fluctuations and maximize preservation benefits.
- Cold Storage Practices: Recommends techniques for preparing material for removal from cold storage to avoid moisture condensation and outlines best practices for using sealed, moisture-proof containers.
Related Standards
ISO 18934:2011 references and aligns with several specialized ISO storage standards for individual media types. Key related standards include:
- ISO 10356: Cinematography-Storage and handling of nitrate-base motion-picture films
- ISO 18911: Processed safety photographic films-Storage practices
- ISO 18918: Processed photographic plates-Storage practices
- ISO 18920: Reflection prints-Storage practices
- ISO 18923: Polyester-base magnetic tape-Storage practices
- ISO 18925: Optical disc media-Storage practices
- ISO 11799: Document storage requirements for archive and library materials (for paper collections, outside the scope of ISO 18934)
Organizations seeking to implement robust archive storage environments for mixed media should use ISO 18934 in conjunction with these standards to ensure best practices in collection longevity and preservation.
Keywords: ISO 18934, mixed media archives, archival storage environment, imaging materials, photographic film storage, magnetic tape preservation, optical disc storage, temperature and humidity guidelines, preservation standards.