CCA Treated Timber Poles
CCA is a preservative containing copper, chromium and arsenic. CCA treatment prolongs the life of timber poles eg: utility poles.
The CCA treatment process was pioneered in 1933 and is used worldwide. Chromium (chrome) ‘locks’ the copper and arsenic into the timber and reduces the risk of the chemicals leaching out. Copper and arsenic protect the timber from insect and fungal attack.
In the pressure treatment process, a solution of CCA is applied using a vacuum and pressure cycle, and the treated wood is then stacked to dry.
The primary advantages in the use of CCA treated timber poles are that it produces no smell or vapor and its surface can be easily painted.
Drawbacks of the wood are a strong green color at high retention values. It should not be used in applications where it is in contact with food or drinking water.
More reading on CCA treatment is available: