Physical preservation begins with a shared vocabulary for how and why materials decay. The dominant framework in the sector is the Canadian Conservation Institute's Ten Agents of Deterioration, adopted internationally as the organising model for preventive conservation. It reframes collection care from reactive treatment of damaged items toward managing the environmental and procedural risks that cause damage in the first place.

Preservation is distinct from conservation. Preservation is the population-level management of risk across an entire holding; conservation is the item-level intervention on a single object. A working programme spends most of its budget on the former, because preventing loss across thousands of items is far cheaper than treating them one by one.

The ten agents of deterioration

  • Physical forces (shock, vibration, abrasion, gravity)
  • Theft & vandalism (and undocumented loss)
  • Fire
  • Water
  • Pests
  • Pollutants (gaseous, particulate, intrinsic off-gassing)
  • Light & ultraviolet radiation
  • Incorrect temperature (too high, too low, fluctuating)
  • Incorrect relative humidity (RH)
  • Dissociation (loss of the link between object and its information)

Inherent vice and material vulnerability

Some decay is intrinsic. Inherent vice describes instability built into a material: acidic wood-pulp paper embrittling, cellulose nitrate and acetate film undergoing autocatalytic "vinegar syndrome", iron-gall ink corroding its substrate, and magnetic media suffering binder hydrolysis. These materials cannot be made permanent; the goal is to slow the reaction, chiefly through cool, dry, stable storage.

Dissociation and the records dimension

For archives, the tenth agent - dissociation - is as serious as any physical threat. A record with a broken link to its context, provenance or catalogue metadata loses evidential value even if the paper survives intact. This is where physical care meets standards such as ISO 15489 for records management and descriptive frameworks like EAD and Dublin Core: order, arrangement and metadata are preservation, not just admin.

In practice. Score each of the ten agents against your holdings for likelihood and severity, then rank them. Most institutions find that a handful of agents - typically water, incorrect RH, pests and dissociation - account for the bulk of realistic loss, and that focusing effort there beats spreading resources evenly.

Key takeaways

  • The Ten Agents of Deterioration give a complete, prioritisable map of every realistic threat to collections.
  • Prevention at population scale is cheaper and more effective than item-level conservation treatment.
  • Dissociation - the loss of object-to-information links - is a preservation risk equal to any physical agent.

Check your understanding

Last modified: Saturday, 1 August 2026, 10:37 AM