Overview
ISO 18906:2000 - "Imaging materials - Photographic films - Specifications for safety film" defines how to determine whether photographic film is a safety photographic film with respect to fire hazards. The standard provides pass/fail criteria and test procedures for both unprocessed and processed films on common plastic supports, covering silver (gelatin and non‑gelatin), colour, diazo, vesicular and magnetic (striped or full‑width) photographic films. Magnetic tapes and video recording tapes are excluded.
Key topics and technical requirements
- Definition: A safety photographic film is one that passes the ignition time and burning time tests specified in ISO 18906.
- Ignition time test (Clause 4)
- Apparatus: electric resistance oven with a temperature measuring device.
- Test condition: oven at (300 ± 10) °C.
- Specimens: three strips 35 mm × 8 mm (approximately).
- Requirement: ignition time ≥ 10 minutes. If any specimen fails, the film fails.
- Burning time test (Clause 5)
- Specimens: three strips 400 mm long × 35 mm wide (full‑width if narrower), marked 50 mm from each end and supported on a fine wire.
- Requirement: films ≥ 0.08 mm thickness - burning time > 45 s; films < 0.08 mm - burning time > 30 s. If any specimen fails, the film fails.
- Informative annexes
- Annex B: a simple field burning behaviour test for quick identification (not a compliance test).
- Annex C: practices for marking safety film (edge/perforation marks or fluorescent additives).
- Annex D: float test to distinguish cellulose nitrate (sinks in trichloroethylene) from cellulose acetate or polyester (floats).
- Scope notes: Applies to most current plastic film bases; does not cover magnetic or video recording tapes.
Applications and who uses it
ISO 18906 is primarily used by:
- Archives, libraries, museums and film repositories for assessing stored film safety and handling/storage decisions.
- Film manufacturers and quality labs to verify film base safety characteristics.
- Conservation scientists and photographic conservators for risk assessment and collection management.
- Fire safety officers, insurers and regulatory bodies concerned with storage, transport and emergency planning for photographic materials.
Practical benefits include clear pass/fail criteria for flammability, simple field checks for rapid triage, and guidance on marking to help identify safe versus nitrate film.
Related standards
ISO 18906 is part of the ISO 18900–18999 series for imaging materials (physical properties and stability). It supersedes ISO 543:1990 and aligns with other ISO 1890x documents covering storage, stability and handling of photographic materials.
Keywords: ISO 18906, safety film, photographic film safety, ignition time test, burning time test, nitrate film, float test, field test, film marking.