Abstract
This paper forms a continuation of the work on treatment of timber products with gaseous borate esters. Turner and Murphy (1995) in an earlier paper indicated that gas flow rate into the wood substrate was the principle factor limiting the rate of boric acid retention and the depth of penetration into wood products. The current paper considers the impact of this factor on treatment efficacy and considers experimental work designed to evaluate qualitatively, the impact of proposed modifications to the process. Significant improvements in treatment performance were observed.