Since 2006, timber suppliers in Brisbane and across Australia have been under voluntary restrictions for CCA treated timber. CCA stands for chromated copper arsenate. It is a preservative treatment for timber that has been in use since the 1930’s. It is made of chromium, copper and arsenic.
CCA is the world’s most common timber preservative. It is subject to both international and national standards which are quite stringent. The chromium is a binder that helps the other parts of the solution adhere to timber. The copper is anti-microbial and helps to protect timber against bacteria and fungi. The arsenic serves as an insecticide and protects against borers and termites.
Arsenic, of course, is toxic to humans. It is found naturally in our food, water and soil, but at what are considered “safe” levels. As more information has become available, many have become concerned about the risk of arsenic exposure due to CCA treated timber. CCA can leach from timber into soil. It can also be absorbed through human skin. The exposure that most fear, however, is from the smoke when it is burned.
Because of the chance of exposure through the skin, there are now voluntary restrictions on CCA timber. In addition, timber that was treated after 7th June 2006 cannot be sold for children’s play equipment, picnic tables, garden furniture or any other external seating, handrails or domestic decking boards.
CCA timber must now be clearly marked, “Treated with copper chromium arsenate” unless it is sold for “small products.” These include veneers, fence palings, battens or droppers. In addition, timber with a cross section less than 1500 m2, less than 15 mm thick or less than 500 mm long doesn’t have to be marked.
Call the Experts
When in doubt, call the experts at Narangba Timbers. We know our timber and we know it well. We can tell you when it is safe to use CCA and when it isn’t.
Call us today for more information: (07) 3888 1293.