The timber preservation industry has faced challenge and change in the past year and this formed the basis of Dr Wolman’s symposium held in Baden-Baden in October. Billed as the First European Wolman Symposium, the event attracted around 120 people from 13 European countries.

Opening the symposium, Dr Wolman managing director Arthur O’Rafferty said the past year “had seen some significant developments on many fronts”, most of them involving the “enormous burden of EU legislation”.

March saw the deadline for submissions on the active ingredients for the Biocidal Products Directive. “This has been expensive and time-consuming,” said Mr O’Rafferty.

On May 1, the EU expanded with the accession of 10 new member countries, “the most significant political and economic development in Europe for a decade”. “It will open new markets but it will also increase competition,” said Mr O’Rafferty.

And July 1 marked the introduction of EU regulations restricting the use of CCA.

And it’s not over yet. Ernst-Werner Wormuth, head of project management at Dr Wolman, said that the new classification of chromium trioxide as carcinogen Category 1 and as very toxic – more severe than that for arsenic – might lead to the EC imposing further restrictions. In addition, discussions on how to handle products containing chromium continue.

However, despite the EC’s strict stance, Mr Wormuth pointed out that requirements for timber treatment plants still differed throughout Europe.

In Germany and the Netherlands not only are there regulations covering the treatment and handling of treated timber, but the manufacture of treatment plants is subject to the Pressure Equipment Directive.

In the UK, the installation of treatment plants is governed by the British Wood Preserving & Damp-proofing Association’s Code of Practice for Safe Design and Operation, while the Health & Safety Executive has jurisdiction over the plant’s construction and the Environment Agency over water and soil protection.

France has no special regulations for treatment plants; instead, they are subject to general industrial laws for the handling of hazardous substances.

Spain, however, is a completely different case. It has no regulations for the construction, installation or operation of treatment plants and, unlike other European countries, they are not subject to any third-party monitoring.

With the use of copper possibly restricted by future EU directives, Dr Frank Runge of Spiess-Urania Chemicals GmbH, came to the metal’s defence.

“From geology to biology, copper is a constituent of life with relevance for most species, including human beings,” said Dr Runge.

Markets for copper

Timber preservation is the third largest market for copper, behind agriculture, where it is used in fungicides for plant protection, animal feed additives and fertilisers, and shipping where it protects ships against fouling.

In all uses of copper, there is one issue: biocidal efficacy versus human health and environmental risk.

In most cases, said Dr Runge, “data evaluation and definition of limit values or safety margin requirements for efficacy as well as for human health can easily be resolved in consensus between industry and regulators”.

Environmental risk, however, can be a matter of dispute. Only once all variables, including long-term background concentration of copper and adaptation of certain populations to changes in concentration, have been considered can the effects of copper on non-target organisms be determined.

A more important issue was bioavailability and this had to be considered within the BPD framework, Dr Runge said.

While the copper industry has organised task forces to address future legislation, Dr Runge, who believes copper has a bright future, said there were “more possible threats for chemicals including copper”.

“The biocidal use of copper will be supported but there may be problems with some applications and some uses may be restricted,” he said.

Decking, garden products and playground furniture are large markets for timber but effective water repellents must be used to maintain timber’s position, said Wolman product manager Dr Mihael Boras.

In the US, timber decking has lost market share to wood plastic composites: in 1992, timber accounted for 96% of the US decking market, by 2002 this had fallen to 91% and by 2007 this may slip further to 83%.

While consumers liked the aesthetic appeal of wood, its durability and dimensional changes caused by water uptake were disadvantages. Various treatments could address these problems. Royal treatment, involving treating and drying before boiling the timber in oil, was effective but also time-consuming and it required additional equipment. Wood modification treatments, such as heat and resin treatments, silylation and acetylation, also required extra equipment and, as they were relatively new to the market, their benefits were not known fully.

The solution, said Dr Boras, was vacuum pressure treatment with a water repellent additive.

“This provides high durability, reduced water uptake, beading and it can be used with existing plant,” he said.

This treatment, which had no impact on the penetration of the preservative, increased durability and dimensional stability and reduced algae growth.