TWO TESTS FOR THE DETECTION OF VOLATILE ORGANIC ACIDS AND FORMALDEHYDE
JINPING ZHANG, DAVID THICKETT, & LORNA GREEN
There are many reported instances of display materials emitting substances that can damage cultural objects in museums (Oddy 1975; Blackshaw and Daniels 1978; Arni et al. 1965; Brimblecombe 1990).
At the British Museum, the “Oddy test” (Oddy 1973) is used to evaluate the suitability of materials proposed for use in the storage and display of antiquities. A disadvantage of this test is that it takes 28 days to complete. Several more rapid tests have been introduced. Daniels and Ward (1982) reported a rapid test using sodium azide for the detection of reducible sulfur compounds that will tarnish silver. A flame test, the Beilstein test, has been used in the British Museum for more than 15 years to detect the presence of chlorine-containing materials. Such materials are considered likely to corrode copper. Williams (1986) published details of this test. Volatile organic acids and aldehydes will cause corrosion of lead (Uhlig 1948) and affect other materials (Green and Thickett 1993; Hatchfield and Carpenter 1987). No rapid tests have been reported for the detection of these substances. The Oddy test with lead is used to detect emissions of volatile organic acids and aldehydes from potential storage or display materials.
Two qualitative tests that take less than 2 hours to complete have been investigated. The iodide-iodate test (Feigl 1954) is used to detect volatile organic acids, and the chromotropic acid test (West and Sen 1956) is used to detect free formaldehyde.