Chromated Copper Arsenate Treated Timbers


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Chromated copper arsenate (CCA) is a chemical registered for use as a wood preservative.

How is Timber Treated with CCA

CCA is injected into wood at high-pressures to saturate the wood. It is used to protect wood from dry rot, fungi, molds, termites and, other pests that can compromise the integrity of the timber.

What are CCA-Treated Timbers Used For?

CCA-treated timbers are commonly used for decks, walkways, fences, gazebos, pergolas, and other outdoor decorations. Other uses include highway noise barriers, signposts, utility posts, and retaining walls.

Disposing of CCA-Treated Timbers

CCA-treated timbers should not be burned, mulched, or used for compost. They should be disposed of using solid municipal waste methods.

Regulation of CCA-Treated Timbers

In the USA, industry has volunteered to cease using chromated cooper arsenate treated timbers by the end of 2003. This decision has been supported by the EPA who will ban chromated copper arsenate treated wood for residential applications.

Alternatives to CCA-Treated Timbers

In response to this regulation, alternative treatments and preservatives have been developed and registered with the EPA. Other possible alternative materials include untreated woods such as cedar and redwood, plastics, metals, and composite materials.

This article was updated on 12th February, 2020.

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