Museums go to great lengths to monitor and regulate the environments in which works of art are displayed, stored, and transported. While many of the variables that affect preservation are considered on a gallery- or museum-wide scale, microenvironments in exhibition cases, packing crates, and storage containers also require oversight. Materials used for fabricating and furnishing vitrines, including wood products, paints, adhesives, textiles, mounts, and gaskets, all potentially produce corrosive vapors that harm works of art. Because of the limited flow of air in both sealed and unsealed vitrines, damaging effects are accelerated, and all materials to which works of art might be exposed must be tested to assure their suitability.

A testing procedure developed by Andrew Oddy, former Keeper of Conservation at the British Museum, was first proposed in a 1973 issue of the Museum Journal and became a widely used tool for evaluating materials for display and storage applications. Lorna Green and David Thickett of the British Museum Department of Conservation later introduced a standardized Oddy test, to be carried out in three sealed glass vials each containing the material to be tested, a coupon of copper, silver, or lead, and a fixed quantity of distilled water sufficient to maintain a relative humidity of one hundred percent. The sealed vials are placed in an oven set to 60ºC for a period of four weeks, after which the metal coupons are inspected for evidence of corrosion. On the basis of changes observed in luster, color, or texture, the materials tested are classified either as suitable for long-term or temporary use, or as unsuitable. A problem still encountered using this standardized procedure is that the containers specified are not airtight, leading to the loss of water vapor and other gases during the test period.

In 1995, as a guide for the Museum's designers and curators, Fairchild Center conservators Ellen Howe, Yale Kneeland, and Pete Dandridge began to assemble a list of materials tested at the Center or otherwise known to be suitable or unsuitable for display and storage applications. In connection with this project, and in order to facilitate more efficient and reliable evaluation of new products, a variation in the Oddy test set-up was developed. During the last six years nearly three hundred materials have been evaluated using the revised system, with the results stored in a departmental database.

Whereas the British Museum procedure places the material to be tested in three separate containers, each with a copper, silver, or lead coupon, the Center's "three-in-one" version specifies that a product sample be placed in a single glass jar with all three coupons (Figures 1, 2). Sufficient space is available to avoid contact between the coupons, the sample, and the distilled water. An improved method for sealing the containers assures that no water vapor or other gases are lost during the test period. A threaded cover lined with a sheet of Teflon® is sealed with silicone grease, and then retightened after the complete set-up has been preheated for half an hour. Each assembly is weighed before and after the twenty-eight day period and the weight loss is consistently zero, demonstrating the reliability of the three-in-one Oddy test.

Joseph Bamberger received degrees in mechanical engineering from the City College of New York and New York University. He was on the scientific staff at Brookhaven National Laboratory for over twenty years, where his work included the design, development, and operation of low-temperature and high-vacuum equipment and facilities. He was active in many of the Laboratory's safety programs, and served as chairman of the Cryogenic Safety Committee. More recently, he taught courses in engineering and technology at Suffolk Community College on Long Island, New York. He has volunteered his expertise at the Sherman Fairchild Center since 1996.

This project received assistance from George Wheeler, Research Chemist, and Diana Harvey, Assistant Conservator. Thanks also to Ellen Pearlstein, Conservator of Objects, Brooklyn Museum.