New treatment standards published

By | 2020-11-02T16:47:55+00:00 November 2nd, 2020|

The revised standards governing timber treatment in South Africa have been published, and certification bodies will now verify treatment plants against the new standards.

The revised standards governing timber treatment in South Africa has been published. Image credit: Leon Louw

The revised standards governing timber treatment in South Africa has been published. Image credit: Leon Louw

It will take time for the certification organisations to audit all treatment plants again and reissue certificates, which will be done as part of the inspectors’ usual work routines and should come at no extra cost to treatment plant owners.

The specifications have been consolidated, simplified, and updated. “Technically, not much has changed, other than removing the H4V specification for vineyard poles, which now fall under H5. Also, the minimum sapwood depth for H5 hardwood poles moved from 20 to 15 mm,” says Bruce Breedt, executive director of the South African Wood Preservers’ Association (SAWPA).

“However, the new standards are easier to understand as they resolve grey areas and get rid of numerous duplications.” Previously, the various commodity (pole) specifications also contained the preservative treatment requirements. When any one aspect of the relevant standards needed changing, a host of other standards needed amending too. This is no longer the case as the preservative treatment requirements for all commodities, including the pole standards, are now covered in SANS 1288.

“It was very confusing to have to cross-reference all the time. We don’t have that problem anymore, although the standards can still be misinterpreted if treaters do not read the fine print,” said Bruce.

In the revised standards, all treatment requirements, from the required moisture content before treatment to the measurement of wood preservative chemicals, and how to ensure adequate penetration and retention levels, are now grouped under SANS 1288. This contains tables differentiating the specs for sawn and round timber.

The pole standards, i.e. SANS 457-2, SANS 457-3, SANS 753 and SANS 754, remain. They will include the physical and material requirements and limitations and will stipulate that preservative treatment must be in accordance with SANS 1288.

SANS 10005 now addresses the lists of approved preservatives, the processes to use, and the handling and safety requirements. This standard also specifies when and where softwood and hardwood species shall be treated if used in structures.

Another benefit of the amended standards is that they clarify the role of the NRCS, which is mandated to enforce compliance with the timber preservative treatments covered in the standards, but not the physical and material requirements of the timber. There has been some confusion about this in the past.

SAWPA issues the standards, which are copyrighted and owned by the South African Bureau of Standards, to its members.

“In future, I see more changes to the standards coming,” said Bruce. “We are awaiting results from research at Stellenbosch University, which may usher in more changes.

“The new standards will simplify the process of making further amendments, which is important because treatment standards should be revised regularly.”

Source: Dolphin Bay Chemicals – the article was first published in the Sawmilling South African Newsletter