Evaluation of Penetration, Retention and Distribution of Chromated Copper Arsenate in Various Wooden Pole Classes in Mufindi District, Tanzania

Abstract

This study examined the penetration, retention, and distribution 
of Chromated Copper Arsenate (CCA) preservatives in four 
classes of wooden utility poles, namely Light, Medium, 
Intermediate, and Stout, in Mufindi District, Tanzania. The aim 
was to evaluate the effectiveness of CCA treatment in improving 
pole durability and service life. Poles were pressure-treated, with 
preservative penetration measured using a graduated plate and 
retention assessed with an ED-XRF analyzer (X-MET8000 
Optimum). Results showed significant differences among pole 
classes in CCA uptake. Light poles had the highest mean retention 
(25.50 kg/m³), while medium poles had the lowest, although stout 
poles demonstrated overall superior retention uniformity. 
ANOVA confirmed statistically significant variations (p < 0.05) in 
both penetration and retention. A very weak positive correlation 
(r = 0.001) between penetration depth and retention indicated 
that factors other than penetration influence preservative uptake. 
Penetration decreased with increasing pole size, from 30.01 mm 
in light poles to 24.97 mm in stout poles, with a general mean of 
27.39 mm. Moisture content was consistent across classes, 
averaging 25.45%. Variations in penetration and retention were 
also noted along pole lengths. The findings emphasize the need to 
tailor treatment protocols to pole size and recommend further 
research into improved preservative formulations and enhanced 
treatment methods to ensure long-term durability.