The evaluation of wood preservatives part I: Interpretation and correlation of the results of laboratory soil-block tests and outdoor test plot experience, with special reference to oil-type materials

This paper offers a review and interpretation of laboratory and field experiments aimed at determining the necessary protective threshold Quantities of wood preservatives. It details the procedure followed in the soil-block tests at the Bell Telephone Laboratories, Incorporated. Discussion of specific criticisms of the techniques involved and replies to these criticisms are included. The paper also presents for the first time a correlation of the results obtained from soil-block culture tests, outdoor exposure tests on stakes and on pole-diameter posts as well as pole line experience. It demonstrates that the same levels for toxicity-permanence requirements (thresholds) are obtained from the three different types of accelerated experimental evaluations. There is every reason to believe that the same limits apply for the outer inch of sap-wood in pine poles in line.