There’s nothing odd about Oddy tests

Jun 8, 2016

Planning a museum exhibition involves countless details, from making mounts for objects on display to writing label text. At Historic New England, our conservation team is testing the materials that will line the display cases for our upcoming show, Mementos: Jewelry of Life and Love from Historic New England.

This test is known as an accelerated aging test or “Oddy test,” after Andrew Oddy, keeper of conservation at the British Museum. It ensures that all materials used in display cases (paint, fabrics, adhesives) are suitable in close proximity to objects for extended periods of time.

First, our staff placed samples from each display material in a glass test tube along with three different metals and a small vial of water. Then, we placed the test tube assembly into a laboratory oven for twenty-eight days with the heat held constant at sixty degrees Celsius. These conditions are meant to accelerate any corrosion of metals that may happen as a result of the case materials off-gassing inside this sealed container.

After twenty-eight days, we evaluated the metal coupons for changes in appearance or color in comparison to known standards. These changes indicate corrosion, meaning that a tested material off-gassed harmful chemicals and thus would pose a risk to historic objects.

Finally, our conservators gave each material one of three grades:

In this case, we were happy to discover that the materials we tested are suitable for permanent use, and therefore safe to come into contact with our historic jewelry.

Oddy testing is a difficult but worthwhile process that ensures the best care for our collection objects. See the results of our careful selections when Mementos: Jewelry of Life and Love from Historic New England opens as the premiere exhibition at the Eustis Estate Museum and Study Center in Milton, Massachusetts, in spring 2017.

To support Historic New England’s work to preserve historic objects, please consider a donation to the Collections and Conservation Fund.