The level of protection required is determined by hazard exposure (i.e. climate conditions, whether the wood will be in ground contact or in a special environment such as salt water), what is expected of the installed product (service life and structural integrity) and the potential costs of replacing damaged wood. The CSA use categories outline the requirements for uses of treated wood products.

The manufacture and application of wood preservatives are governed by CSA O80 standards. These consensus based standards dictate the wood species that may be treated, the allowable preservatives and the retention and penetration of preservative in the wood that must be achieved for the use category or application.

For more information on how to specify non-residential treated wood products, please visit the Specifiers Guide Section.