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This test method describes an accelerated laboratory procedure for determining the corrosion rate of metals when in contact with preservative treated wood. The test is not designed to predict absolute corrosion rates, but rather to provide a corrosion rate in comparison to wood treated with a preservative that has known corrosion characteristics. The procedure exposes metal samples between treated wood blocks at set conditions and the corrosion rate in mils per year is calculated from the data. The rate can not be extrapolated to all possible scenarios and the precision and bias of the method is under investigation. The results obtained with this procedure are highly dependent on procedure variables and the care taken in performing the work, and does not accurately reflect realworld corrosion rates. Important factors include metal specimen preparation (cleaning), environmental exposure conditions, wood moisture content, post-exposure specimen cleaning, and possibly others. It is critical that wood treated with an appropriate control preservative be included in a test. Comparisons should be made only against wood treated with those control preservatives, with all experimental parameters held constant. A detailed discussion of corrosion test procedure variables is given in NACE Standard TM0169-76 (Item No. 53003, National Association of Corrosion Engineers, and P.O. Box 218340, Houston, TX 77218). It is recommended that the first time user consult the NACE standard prior to using this AWPA standard. Additional background material and a general discussion of corrosion testing can be found in Fontana.