Pressure Treatment of Fresh and Ponded Heritiera mirror (Roxb.) Logs with Chromated Copper Arsenate (CCA)

Abstract

Sundri (Heritiera minor Roxb.) is a hardwood species which exhibits good strength qualities. They have potential for use as electric poles but their short service life posed a problem. This study examined whether treatment with the preservative Chromated Capper Arsenate (CCA) by full cell pressure method at 15.40 - 16.10 kg/cm2 for 8 hours could extend their service life. The samples tested were processed fresh and ponded H. minor logs of approximately 1 m length and 0.25 m diameter. Results showed that that the preservative treatment gave a mean penetration value of 23.84% log radius for fresh specimens and 32.29% for ponded logs, which were short of the standard requirement of 44% log radius penetration. The preservative retention of ponded logs was within the acceptable standard values of 20 kg/cm2of dry oxide basis, but that offresh logs did not meet the standard requirement. Thus, the full pressure treatment can extend the service life of H. minor to a certain extent in which ponded logs gave encouraging response to the preservative treatment.