26 September 2016
Fingerprints & their potential impact in relation to handling library collections
Back in early 2016, Terry Kent, a consultant specialising in forensic fingerprint analysis, contacted British Library Conservation to learn more about how we assess the impact of handling on our collections with reference to our use (or not) of gloves in the reading room. This was pertinent timing for us since we were on the cusp of refilming and updating our videos that provide instructions to library users about handling collection items. We invited Terry to the British Library to discuss the issue with us in more depth as part of our Continuous Improvement Programme.
In June, Terry Kent gave a presentation about the potential effect of fingerprints on paper artefacts at the ICON (Institute of Conservation) Conference ‘Turn and Face the Change’ in Birmingham. Lively debate ensued. It became clear that there is some perception that the British Library has a blanket policy of no gloves - regardless. Not so, and in this blog post we would like to give brief insight, with Terry’s contribution, into how we assess and mitigate risks to collection items to enable access to and use of a vast and varied collection in a working research library (and how this then helps us form a handling policy).
By way of background:
- The British Library has 12 reading rooms; 11 at St Pancras, London and 1 in Boston Spa, West Yorkshire.
- These have 1200 reader desks and accommodate 400,000 reading room visits per year.
- Reading rooms are divided into general and special collections, and focus on different subject areas (e.g., Humanities, Maps, Rare Books & Music and Science).
- To request items readers need to register for a reader pass and sign the conditions of use.
Given this level of use the challenge is to balance the need to make items available to users while at the same time protecting them from further degradation and potential damage in order to ensure their longevity. Collection items are assigned different reading categories, based on factors including their age, condition, and value (historical, religious, cultural, etc.) which affects how and when they can be used, for example:
- Which reading rooms they can be read in.
- Whether there is a digital copy (or other surrogate) which should be referred to instead.
- Whether readers need to provide additional information about why they need particular items before they can be issued.
- Whether or not the items can be copied.
- Whether readers need to sit at invigilated desks when they use the items or meet other conditions of use in order to use them.
Where readers are using original items we encourage them to handle items as little as possible and with care as we know that even with careful handling collection items face risks.
A range of different factors can damage collections and lead to loss - these are summarised in the figure below.
Of these ten categories, any risks presented by fingerprints due to sweat transfer would be covered by ‘Contamination’ (which also includes aggressive volatiles, pollutants and other damaging chemicals). Any potential risk to an item must be considered in light of a number of factors - the likelihood of it occurring, the extent and nature of damage it will cause if it does occur, the degree to which it will limit how the item can be used, and the measures that can be taken to limit or prevent it.
Risks do not exist in isolation, so responses to risks - such as the use, or not, of gloves - must be based on a comprehensive understanding of the nature of an item, its vulnerabilities and the requirements for its use by staff and readers. Furthermore, solutions to any such problems must not exacerbate other risks or introduce new ones.
Terry Kent writes,
A widely referenced paper, in the conservation field, and several forensic references, refer to fingerprint deposits consisting of 'over 98% water'. Recent analytical and theoretical studies of latent fingerprints, demonstrate that this figure is substantially in error. The deposit from a single human finger touch, whilst varying widely between individuals, is likely to contain less than 20% water and on average be about four micrograms of a mixture of amino acids, salts, primarily sodium and potassium chloride, fatty acids, squalene and many other trace compounds.
What is less well researched is the effects such deposits may have over time on substrates such as papers and textiles. We know that body soiling of fabrics will lead to yellow-brown staining, and fingerprint deposits on some papers will darken when heated (accelerated ageing using elevated temperatures); although it is unclear whether this will occur at lower temperatures over longer time periods.
There are other potentially negative effects of fingerprint deposits from a conservation standpoint; again not well researched, these include the effects of microbial or bacteriological activity on such deposits. There is also the potential of the deposit to attract and retain dust and other material from the environment.
The protective effect of hand washing, standard practice for many institutions and effective for the removal of transferred dirt, is less effective for the secretions which lead to fingerprints - it has been shown recently to be negated by natural replenishment of secretions in as little as five to ten minutes. So we need to consider the likely impact of these deposits on various substrates.
We are always looking at new evidence to challenge or support our current practices. Clearly fingerprints do have an impact on library and archive materials, although the extent of this is not yet clearly understood. The impact must be considered in light of other risks to the collection items given the context in which we work. Our policy is tailored to the requirements of individual items and the risks they face and the way they can be accessed and consulted. There is no one size fits all. Fragile, rare and significant items are subject to much tighter access and handling controls to minimise risks (including fingerprints) compared with items on open access. A core purpose of the British Library is to allow access to the national collection and our role in conservation is to manage that process as effectively and pragmatically as possible. We hope this blog post generates some thought and debate on the subject of handling and the impact of fingerprints. The collective authors plan to present their thoughts in a longer article in a future ‘ICON News’.
Cordelia Rogerson, Paul Garside, Sarah Hamlyn with thanks to Terry Kent for co-writing this post.