Wood Preservatives: New Report Explores Directions and Possibilities

A new report has just been published: Wood Protection Research Council, Research Priorities 2013

In this report, authors Carol A. Clausen, Frederick Green III, Grant T. Kirker, and Stan T. Lebow report on findings and recommendations from the Wood Protection Research Council.

Why wouldn’t a homeowner want to build with wood? Sometimes homeowners do not select wood as a building material because of its vulnerability to biodeterioration by fungi and insects under certain conditions of storage and use. These limitations are also a prime cause of user dissatisfaction. Therefore, efforts to protect wood from biological degradation are among the earliest research at the Forest Products Laboratory. This research has successfully reduced the demand for lumber from our National Forests by reducing the need to repeatedly replace existing wood products.

WPRC-cover-art

The cycle of wood harvest, research, and use protects our natural resources.

Wood protection has undergone dynamic changes since the industry voluntarily withdrew chromated copper arsenate (CCA) from most residential uses and new products were introduced to the marketplace. According to the Environmental Protection Agency (EPA), “CCA is a chemical wood preservative containing chromium, copper and arsenic. CCA is used in pressure treated wood to protect wood from rotting due to insects and microbial agents. EPA has classified CCA as a restricted use product, for use only by certified pesticide applicators.”

Obviously, alternatives for wood protection are needed. However, to bring a new preservative to the marketplace, a considerable amount of performance data needs to be obtained. Current laboratory methodologies to determine the durability of test specimens are insufficient, and long-term field testing is required to ensure that a treatment is effective.

Improved accelerated test methods to predict performance would reduce the time needed for the development and acceptance of new preservatives. Potential improvements for accelerated testing may include selection of test fungi, techniques to detect incipient stages of fungal decay, methods to properly assess durability of wood plastic composites use of rapid laboratory bioassays for screening, and field tests that could measure loss in mechanical properties and statistical analysis.

Possibilities and research opportunities abound. For instance, protection systems could be targeted to specific problems. With nanotechnology at the forefront, novel advances in wood protection could replace the broad spectrum biocides traditionally used to inhibit decay fungi. The most logical approach to develop targeted biocides is to take advantage of unique physiological attributes of decay fungi, such as their ability to sequester metals through production of oxalic acid or natural tolerance to preservatives. Discerning and describing these mechanisms may enable us to design specific, targeted inhibitors to control decay and circumvent preservative tolerances that are common in brown-rot basidiomycetes.

This report summarizes presentations and comments from the inaugural Wood Protection Research Council meeting. Research needs for the wood protection industry were iden­tified and prioritized. Methods for successfully addressing research needs were discussed by industry, academia, and association representatives.

 

 

 

Fire Safety for New Wood Products FPL's History in Fire Research

A compelling issue at FPL is how we ensure that traditional and new innovative wood products do not adversely contribute to loss of life and property in fires.The Durability and Wood Protection Research at FPL is prepared to answer these questions. A part of the group’s mission is improving durability and wood protection through improved building design, advances in low-toxicity wood preservatives, and improvements in fire safety.

With unique fire research facilities, fire safety research at FPL addresses the potential contribution of wood products to the growth of a fire, the ability of structural wood elements to withstand a fire, and the chemical treatment of wood products to reduce their flammability. Fire safety is a major component of existing building codes and will be continue to be so in future developments of editions of the building codes and other regulatory documents.

flashpoint

This burning test structure from 1975 is at the point of flashover—the sudden spread of flames over an area when it becomes heated to the flashpoint. Results of these tests indicated that sandwich panels provided structural integrity for various lengths of time depending on the facing material used for the panels.

FPL has worked on fire safety for decades and has helped quantify the fire performance of wood products. This research has contributed to the development of treatments of wood that reduced their flammability. Research helped define the fundamentals of fire behavior and efforts to develop methodologies for fire testing of wood and composite materials to ensure proper measurements of relevant performance characteristics. More recently, contributions have been toward data and models required for fire safety engineering of forest products in a performance-based building code environment.