Adding the PA additive to CCA provides poles with benefits comparable to PCP such as preventing hardening, while retaining the advantages of a water-borne treatment, and this over the service life of the pole.
From the end of the 1930’s to the beginning of the 80’s, pentachlorophenol (PCP) was widely used in the preservative treatment of wooden poles and railway ties. In 1981, Agriculture Canada raised concerns regarding the use of PCP and restricted it to the preservation of wood for outdoor use.
Although the railway tie market adapted by using treatments based on creosote-oil solutions, PCP continued to provide benefits for utility poles. However, due to health and safety concerns, public utilities were still trying to reduce the use of PCP-treated poles. In fact, regulators and industry have decided that PCP-treated poles will no longer be produced after 2021.
Poles treated with CCA (chromated copper arsenate) and public utilities have been progressively replacing PCP-treated poles. Over the last decades, the popularity of CCA- treated poles has increased significantly in North America; they are now widely accepted.
Unfortunately, the CCA treatment tends to harden the wood over time, making it more difficult for the linesmen to drill and climb. This is one of the reasons why PCP usage was maintained for some applications.
Testing was undertaken to find a solution to the hardening of poles treated with CCA, including the addition of polyethylene glycol (PEG) to the preservative solution. This additive solved the hardening problem – for a while. Unfortunately, extensive laboratory and field testing has shown the effect of PEG on pole hardness to last no more than 3 years. The long-term results were less than satisfactory, as the effect waned and the poles became too hard to safely climb.
In 1998 an R&D partnership initiated by Hydro-Québec with Lonza Wood Protection, developed a polymer-based additive (PA), which, when injected into CCA-treated wood poles, offers the benefits of a CCA-treated pole, as well as the climbability benefits of poles treated with oil-borne wood preservatives. The result is the CCA-PA treated utility pole, approved by Hydro-Québec, Bell Canada and Group CSA (O80.207-05 standard), and already in widespread use.
Adding the PA additive to CCA provides poles with benefits comparable to PCP such as preventing hardening, while retaining the advantages of a water-borne treatment, and this over the service life of the pole. A pole treated with CCA-PA offers:
As of the summer of 2020, Trans Canada Forest Products is able to supply utility poles treated with CCA-PA (Chromated Copper Arsenate with Polymer Additive). In use for over 20 years, the CCA-PA treatment offers the best of both worlds: the benefits of pentachlorophenol, as well as those of CCA, but without the disadvantages of either. It is a clean, durable and accessible solution for the development of any electrical network.
We have availability in poles from 25’ to 65’ in all industry recognized classes.
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