The
Oddy test is a procedure created at the
British Museum by conservation scientist William Andrew Oddy
in 1973,
[W.A.Oddy, "An unsuspected danger in display", Museum Journal 73, 1973, p.27-28] in order to test materials for safety in and around art objects.
Often, materials for construction and museum contexts (including artefact conservation) are evaluated for safety. However, though materials may be safe for building purposes, they may emit trace amounts of chemicals that can harm art objects over time.
,
formaldehyde, and other pollutants can damage and even destroy delicate artifacts if placed too close.
Procedure
This test calls for a sample of the material in question to be placed in an airtight container with three coupons of different metals—
silver,
lead, and
copper—that are not touching each other or the sample of the material.
[Schiro,Mara "Oddy Test Protocols" http://www.conservation-wiki.com/index.php?title=Oddy_Test_Protocols&oldid=4830 Accessed February 6, 2012.] The container is sealed with a small amount of de-ionized water to maintain a high
humidity, then heated at 60 degrees
Celsius for 28 days. An identical container with three metal coupons acts as a control. If the metal coupons show no signs of
corrosion, then the material is deemed suitable to be placed in and around art objects. The Oddy test is not a contact test, but is for testing
outgassing.
Each metal detects a different set of corrosive agents. The silver is for detecting reduced sulfur compounds and
. The lead is for detecting organic acids,
aldehyde, and acidic gases. The copper is for detecting
chloride, oxide, and sulfur compounds.
There are many types of materials testing for other purposes, including and .
Development
The Oddy test has gone through many changes and refinements over time. Whereas Andrew Oddy proposed to place each metal coupon in a separate glass container with the material to be tested, Bamberger et al.
[Studies in Conservation, Vol. 44, No. 2 (1999), pp. 86-90.] proposed a "three-in-one" test, where all three metal coupons shared one container, simplifying the procedure. Robinett and Thickett (2003)
[Studies in Conservation, Vol. 48, No. 4 (2003), pp. 263-268.] refined the "three-in-one" test by stabilizing the metal coupons.
One of the main issues with the Oddy test is that there is some subjectivity to the interpretation of the results,
Institutions that use the Oddy test in their research are mainly art museums such as The J. Paul Getty Museum, The Nelson-Atkins Museum of Art, and the Metropolitan Museum of Art.
Further reading
