An important part of the brand is the Hazard Class, which indicates the service conditions to which the product is exposed and the level of treatment or level of protection that must be applied to the wood.
| H4 | H5 | H6 |
| This level of treatment is suitable for use in applications where the timber is in contact with ground or is continually damp. H4 is designed to eliminate the likelihood of attack by insects, including termites, and decay where a critically important end use is involved such as posts and garden edges. | A stronger level of protection, H5 is suitable for use in applications where the timber will come in contact with the ground or fresh water such as as posts and pylons. Other than protecting against the likelihood of attack by insects, H5 also offers protection against extreme decay. | As protection against the highest level of hazard, H6 is appropriate for applications where the timber will be in prolonged contact with sea water. H6 is designed to minimise the likelihood of attack by marine borers and extreme decay, such as boardwalks, piers and jetties. |
Generally, the higher the Hazard Class, the greater the penetration and retention of preservative specified in the Standard. SOURCE: TPAA Tech Note – Understanding Hazard Classes
Preservative treated wood is wood that has been treated with one or more chemicals intended to protect it from borers, insects, and rot (or decay). Surface applied coatings, such as paint, varnish and stain, are not considered wood preservatives. A list of the different preservative types is provided in TPAA Tech Note - Preservatives used to treat wood
The following evaluation tools can help you determine if the waste wood has been treated.
Treated wood waste includes treated wood debris from construction activities and may include trimmings, off cuts, scrap and sawdust. Treated wood waste also includes demolition products permanently removed from use, e.g. decks, fences, docks.
Treated wood materials may be reused in a way that is consistent with their original use. Recycled treated wood is not considered to be waste material.
The service life of treated timber depends on a variety of factors including the level of preservative treatment and the specific application of the product (refer to treatment hazard classes).
The range of conditions and the type of environment anticipated during the service life of the product can vary based on climate, geographic location and seasonal changes. In consideration of service life, if subsequent machining, shaping, pointing cutting and scarfing of treated timber posts and poles are unavoidable, supplementary protection should be applied to the cut surface. This protection however cannot be expected to be as effective as the original treatment application. If actions are undertaken that compromise the integrity and treatment application of the product, Portland Pine Products will not be responsible for subsequent issues arising from such actions and any warranties shall be considered null and void by any further processing of treated products.