In a series of three papers published in Heritage Science researchers at the UCL Institute for Sustainable Heritage have developed a demographic model to predict how historic paper will degrade in museums and measures that can be taken to mitigate this. Matija Strlič, lead author and Editorial Board member of Heritage Science commented that “In times when libraries and archives struggle with resources and carbon reduction targets, we have produced a collection model that allows institutions to optimize environmental control and access to collections while minimising the costs. This involved ground-breaking research into paper chemistry, indoor environments, and visitor attitudes to collections. It is exceptionally exciting to see research coming to fruition which involved almost 900 volunteers and an international cross-disciplinary team.”

In times when libraries and archives struggle with resources and carbon reduction targets, we have produced a collection model that allows institutions to optimize environmental control and access to collections while minimising the costs

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Matija Strlič, Deputy Director of UCL Institute for Sustainable Heritage

In the first of the three articles in the “Damage function for historic paper” series, Matija Strlič and colleagues assessed the fitness for use for archival and library paper documents by the general public. Over 300 participants from the general public were asked to consider change to the documents in the context of discoloration and signs of wear and tear (mechanical degradation). The outcome of this paper suggested that in general items become “unfit” for use when text is missing however in cases where the participants were prompted to think of the historical value of the document showed that changes had little impact on the assessment of the fitness for use.
Following on from this initial paper the authors developed a model depending on the degree of polymerization of cellulose in historic paper to calculate the time required for an object to become unfit for use. Using the average frequency of document use at the UK National Archives the authors were able to predict based on the DP values how many years it would take for individual objects to be deemed unfit in the context of general access. In certain cases where objects have a DP value of above 500 this period is found to be above 450 years and so deemed to not be a significant collection management concern for today while when DP values were less than 300 the object was likely to develop significant wear and tear in a single instance of handling.

Continuing in the theme of planning for the future this work has also focussed on using the developed models and tools to evaluate the management of storage environment and access levels for specific collections. These models also allow the costs and benefits of conservation interventions to be evaluated so that informed decisions can be made on the management of historic collections.

This series of papers are available fully open access on the Heritage Science website at http://www.heritagesciencejournal.com/

Damage function for historic paper. Part I: Fitness for use

Damage function for historic paper. Part II: Wear and tear

Damage function for historic paper. Part III: Isochrones and demography of collections