Overview
ISO 18923:2000 - "Imaging materials - Polyester‑base magnetic tape - Storage practices" provides international recommendations for the storage of recorded polyester‑base magnetic tapes in roll form. It covers both analog and digital tape formats used for audio, video, instrumentation and computer applications. The standard focuses on medium‑term (≈10 years) and extended‑term (≈50 years) preservation of master tapes and is explicitly not intended for routine "work" or frequently used copies (see informative annex C).
Key topics and requirements
- Scope and applicability
- Applies to polyester‑base magnetic tape (and is also relevant to triacetate bases) in roll form.
- Intended for master tape storage, not work copies.
- Environmental controls
- Medium‑term storage: recommended relative humidity 15–50% RH; maximum long‑term temperature 23 °C, short‑term peak 32 °C. Avoid storage below 8 °C (lubricant separation risk).
- Stability limits: temperature cycling ≤ ±2 °C/24 h; RH cycling ≤ ±10%/24 h.
- Extended‑term storage: lower temperature and/or lower RH increases life expectancy; see annex D for temperature/RH relationships.
- Facilities and enclosures
- Recommendations cover storage housing (racks, cabinets, drawers), room design, enclosures (containers, shells, cassettes) and fire‑protective storage solutions.
- Preparation and handling
- Guidance on tape preparation, splicing, leaders, and correct winding (heads out/tails out), to minimize physical stress and print‑through.
- Inspection and maintenance
- Identification, scheduled inspection, cleaning and staging (acclimatization) procedures to detect and mitigate deterioration.
- Terminology and annexes
- Defines terms (e.g., popped strand, stepped pack, leafing) and includes informative annexes (numbering system, cellulose triacetate stability, acclimatization).
Practical applications - who uses it
- Archives, libraries, museums and government agencies preserving audio/video masters.
- Broadcasters and production facilities managing master videotape storage.
- Corporations and data centers maintaining long‑term magnetic tape backups and archival media.
- Conservation specialists and facilities planners designing storage rooms, HVAC, and fire‑protective vaults.
- Procurement and quality teams selecting enclosures, cartridges and environmental monitoring systems.
Related standards and references
ISO 18923 references international and national standards for environmental control and record protection, including NFPA (records/fire protection) and ASHRAE guidance for HVAC and humidity control. Users should consult these documents when designing storage systems.
Keywords: ISO 18923, polyester‑base magnetic tape, magnetic tape storage, tape preservation, archival storage, master tapes, temperature and humidity, RH limits, medium‑term storage, extended‑term storage.
