CCA Treated Wood

CCA treated wood is an environmentally friendly material

When you select CCA treated wood you not only build projects that last, you invest in the conservation of our forest resources.

CCA treated wood will last much longer than it takes replacement trees to be grown and converted into wooden products.

The CCA treating process extends the life of wood requiring fewer trees to be cut. To achieve long life the wood is pressure treated with a preservative to resist decay and insect attack.

Safety and the environment

Because your safety and the safety of your family and friends is important to the producers of CCA treated wood we want you to have all the facts.

Our recommendations are intended to reflect common sense and good hygiene practices as apply when building with any wood product.

  • When power-sawing/machining any timber wear goggles to protect eyes from flying particles and a mask to avoid dust inhalation.
  • If sawdust accumulates on clothes, launder before re-use. Wash work clothes separately from other household clothing.
  • After working with CCA treated wood wash hands before eating, drinking, smoking or otherwise placing your hands near your mouth or rubbing your eyes.
  • CCA treated offcuts and sawdust should not be burnt nor used in barbecues. Disposal to a designated landfill is appropriate.
  • Ensure that any dust and residue on the surface of the wood is washed off prior to use.

CCA treated timber is safe to use in normal circumstances. The preservative reacts with the wood to form chemical complexes that are highly insoluble and leach resistant. The CCA preservative penetrates deeply into and will remain in the wood for a long period of time. However very small quantities of preservative may migrate from the preserved wood into the surrounding soil over time and there may also be incidental contact with skin during construction or use. This contact is highly unlikely to pose a significant health hazard.

Care in use

  • CCA treated timber is commonly used for structural and decorative purposes outdoors
    including fences, decks, landscaping, pole houses, playground structures, marinas and
    walkways.
  • CCA treated wood should not be used where it may come into direct or indirect contact with public drinking water except for uses involving incidental contact such as fresh water docks and bridges.
  • CCA treated wood should not be used in the manufacture of toys for young children or for use as cutting boards, counter tops, food bins or similar applications involving contact with food.
  • Do not use CCA treated wood shavings for animal litter or mulch.
  • Cutting, drilling or machining CCA treated timber may affect the integrity of the treatment. To counter this all cut surfaces should be coated with a brush on preservative.

Facts About CCA Treated Wood

  • CCA preservative contains:
    • Copper and arsenic - to protect against fungal decay and wood boring insects
    • Chromium - to fix the preservative to the cell structure in the wood.
  • Fixation of the preservative in the cell structure provides long term protection for the wood. Any leaching is extremely minimal.
  • The arsenic content in CCA treated wood is not readily bioavailable - humans do not normally eat and ingest any form of wood; the greatest risk is through exposure to smoke and ash which is why this wood should not be burnt.
  • Adverse health risks due to absorption of arsenic through direct exposure to treated wood surfaces are highly unlikely. Tests conducted in the USA on playground equipment have shown dislodgeable arsenic on most samples to be at levels that do not pose a health risk.
  • An independent panel of physicians in Florida have reviewed all the literature on the natural occurrence and bioavailability of arsenic and its impact on people and the environment. They concluded that the amount of arsenic that could be absorbed from CCA treated wood and surrounding soil was insufficient to adversely affect the health of children and adults. It was not significant compared to natural sources and would not result in a detectable arsenic intake.

WOODmark® branded timber - your assurance of quality treatment

Reputable CCA treaters are licensed to use the WOODmark® brand. The WOODmark® brand signifies that timber has been treated to the requirements of the New Zealand Standard MP3640:1992 and that the treater follows the quality assurance procedures laid down in the New Zealand Timber Preservation Council's Timber Preservation Quality Manual.

Make sure you buy and use only WOODmark® treated timber and wood products.