The SANS specifications that apply to our industry are under constant review in various industry forums. However, many wood treaters are not party to all these discussions. To help you stay up-to-date on important technical issues, and thereby help you to produce top-quality treated timber, we launched a publication called ‘Industry Note’ in January this year. The first edition, which was distributed to all our clients, outlines a simple and cost-effective way of ensuring that CCA does not leach out of your treated timber. This method – the use of diphenyl carbazide as an indicator – is expected to become law later this year.This will keep your clients satisfied with your product over time, safeguard your workers, protect the environment and, of course, comply with the law. “Some treaters are moving timber straight after treatment, which results in chemicals leaching from the wood,” says Dolphin Bay chemical lab manager Navi Moodley. “However, we need to keep in view that fixation is part of the whole process. It’s a huge waste if the job isn’t finished properly.”The January edition of ‘Industry Note’ focuses on the use of diphenyl carbazide to indicate whether CCA has fixated properly into your timber. Increment bore samples can be taken from the wood, and the indicator sprayed onto these samples.
Both SANS 10005 and SANS 5993:2004 require the use of an indicator to determine fixation. The amendments to the latter, which are expected to be implemented by the end of this year, prescribe diphenyl carbazide as an indicator. The time needed for fixation is inversely proportion to temperature. At room temperature, it takes between two to three days, and at 5 degrees Celsius, about 27 days. Some treaters us a kiln, which makes fixation occur within hours. Industry Note contains a graph from the SANS specifications outlining the time required for fixation at various averages temperatures.
“Dispatching wood too quickly, before fixation has taken place, can pose an environmental risk,” says Bertus. “We will use Industry Note to communicate all aspects of the SANS specs that we believe are the most important for our clients. We will also be honest if we disagree with any developments. “Distributing this information is part of our dedication to client service, and doing all in our power to ensure the success of our clients’ businesses.”