15th Annual Preservation Conference

Conference Topic: Deacidification Reconsidered

Held on March 28, 2000,
at the National Archives Building
700 Pennsylvania Avenue, NW
Washington, DC

The National Archives and Records Administration's Annual Preservation Conferences cover topics on the creation, use, exhibition, care and handling, conservation, duplication, and long-term storage of information on paper, film, tape, and disk. This year's Conference brought together conservation scientists, preservation professionals, and conservators to discuss technical issues related to deacidification.

A number of deacidification methods exist to preserve library and archival paper records. Selecting deacidification as a treatment option involves understanding the distinction between various methods and what they accomplish, and a careful assessment of the materials to be treated. Concerns that often guide the decision include: the nature and condition of the paper substrate; the media and other non-paper materials that may be part of the items; the dimensions, format, and quantity of items requiring treatment; the intrinsic value of the material; the efficacy of the proposed method; and evaluation of one's resources.

Please note that some of the speaker's titles, institutions they may be associated with, and contact information below may be obsolete.


Chemical, Architectural, and Mechanical Features of "Paper" and Its Deterioration: An Overview

Hal Erickson ( , Preservation and Conservation Studies, Graduate School of Library and Information Science, University of Texas at Austin
A brief review of the chemistry of paper's major components, of the architecture of the paper matrix and the internal architecture of paper "fibers," and of the mechanical interactions that determine the working properties of a sheet, followed by a review of how these insights inform our understanding of the mechanisms of deterioration of paper.

Mechanisms of Washing and Mass-Deacidification

Hal Erickson (, Preservation and Conservation Studies, Graduate School of Library and Information Science, University of Texas at Austin
An overview at several levels of the very different mechanisms of washing and mass-deacidification, with special emphasis on the necessity of understanding both as processes that occur at phase boundaries. Prerequisite concepts not addressed in the preceding presentation was covered, notably including mechanisms of solvation, morphology of alkaline reserves and the distinction between pH and alkaline reserve.

Chemical Studies of the Beneficial Effects of Calcium-Enriched Wash Water

John Bogaard ( , Research Scientist, Carnegie Mellon Research Institute
In the course of treating archival materials or works of art on paper the conservator may want to immerse the object in water containing trace amounts of calcium. Recent research has explored the chemical benefits of such treatments and results of treatments with various calcium containing baths.

New Insights into the Effects of Deacidification Treatments and Storage Environments on the Life of Paper-Based Collections

Chandru Shahani (, Chief, Preservation Research and Testing Division, Library of Congress
Implications on the deacidification of paper and its long-term storage by research carried out over the past few years suggests that acidic paper ages at a rate that is appreciably faster than has been indicated by currently accepted laboratory-aging tests.

Saving the Written Word: Mass Deacidification at the Library of Congress

Kenneth E. Harris Director (former), Preservation Projects, Library of Congress
The presentation described how a mass deacidification program can be successfully adopted and managed in a library setting, focusing on selection criteria, work flow and quality control measures, and unexpected benefits of such a program.

Mass Deacidification: Considerations for Archives

Norvell Jones, Chief (former), Conservation Laboratory, NARA
Archival holdings have more in common with manuscript collections than libraries, but there are still some significant differences that influence how archives decide to approach mass deacidification. They include intellectual control issues and questions of diversity of format and media.

All in a Day's Work: Why and How I Deacidify

Christine Smith (, Paper Conservator, Conservation of Art on Paper, Inc. Alexandria, VA
This presentation covered the factors one conservator weighs when deciding whether to deacidify various kinds of objects, including direct and indirect deacidification methods such as aqueous calcium and magnesium compounds and a non aqueous magnesium spray, with emphasis on the hazards of potential color changes and the tools the speaker has found useful and problematic.

Treatment of Previously Deacidified Paper Artifacts

Elissa O'Loughlin, Senior Conservator at the Walter's Art Gallery in Baltimore, MD, and Anne Witty (, Senior Conservator, Conservation Laboratory, NARA
The speakers addressed the impact which previous deacidification may have on the treatment and care of paper artifacts.
A published version of their paper appears in:
British Museum Occasional Paper No. 135, 1999
Reversibility--Does It Exist?
Edited by Andrew Oddy and Sara Carroll
Published by The British Museum
Distributed by:
The British Museum Press
46 Bloomsbury Street
London WC1B 3QQ

Deacidification Manufacturers represented were:

  • Neschen, the Buckeburg (Germany) automated aqueous method

  • Preservation Services Bookkeeper process (USA), currently used by the Library of Congress for mass deacidification

  • Wei T'o non-aqueous method (USA)

  • The Centre for Book Preservation (Germany)