Chromated copper arsenate

Wood preservative containing compounds of chromium, copper, and arsenic

Chromated copper arsenate (CCA) is a wood preservative containing compounds of chromium, copper, and arsenic, in various proportions. It is used to impregnate timber and other wood products, especially those intended for outdoor use, in order to protect them from attack by microbes and insects. Like other copper-based wood preservatives, it imparts a greenish tint to treated timber.

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