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Preservative-treated wood contains components that may be toxic to non-target organisms if released into the environment in sufficient quantities. Numerous studies have been conducted to determine the rate of preservative release from treated wood and/or the extent of their subsequent accumulation in the environment. These studies have produced a wide range of results, with a corresponding range of interpretations and recommendations. This paper reviews research on wood preservative leaching and environmental accumulation and discusses sources of the variability in research findings....

To keep pace with customer demands while phasing out old and unserviceable test equipment, the staff of the Engineering Mechanics Laboratory (EML) at the USDA Forest Service, Forest Products Laboratory, designed and assembled a hydraulic bending test machine. The EML built this machine to test dimension lumber, nominal 2 in. thick and up to 12 in. deep, at spans up to 20 ft and loads up to 20,000 lbf. The hydraulic bending test machine was built using parts of a 100,000-lbf compression test frame. Added components included W12 by 65 steel beams; steel tube sections, L sections, and...

This report provides general and statistical information on forests products markets in terms of production, trade, consumption, and prices. The state of the United States economy is described as of the second quarter of 2003. Market developments are described for timber products, paper and paperboard, fuelwood, and forest products prices. Policy initiatives that address domestic markets and international trade concerns related to U.S. forest products are also discussed. Detailed information and projections are presented for the year 2004.

Occasionally, creosote-treated railroad ties need to be replaced, sometimes in sensitive environments such as wetlands. To help determine if this is detrimental to the surrounding environment, more information is needed on the extent and pattern of creosote, or more specifically polycyclic aromatic hydrocarbon (PAH), migration from railroad ties and what effects this would have on the surrounding environment. This study is a report on PAH level testing done in a simulated wetland mesocosm. Both newly treated and weathered creosote-treated railroad ties were placed in the simulated wetland....

This guide was prepared to assist field foresters in the use of stress wave timing instruments to locate and define areas of decay in standing timber. The first three sections provide background information, the principles of stress wave nondestructive testing, and measurement techniques for stress wave nondestructive testing. The last section is a detailed description of how to apply stress wave nondestructive testing methods to standing timber. A sample field data acquisition form is included.

Piloted ignition behavior of materials, particularly wood products, during transitions between heating regimes is measured and modeled in a cone calorimetry (ISO 5660) heating environment. These include (1) effect of material thickness, density, moisture content, and paint coating variations on thermal response characteristics, (2) effect of fire retardant treatment concentration on smoldering and flashing prior to flaming ignition, and (3) effect of cone irradiance on inducing convective heat loss of the material. Thermophysical properties of volumetric heat capacity or thermal conductivit...

Existing log grading procedures in the United States make only visual assessments of log quality. These procedures do not incorporate estimates of the modulus of elasticity (MOE) of logs. It is questionable whether the visual grading procedures currently used for logs adequately assess the potential quality of structural products manufactured from them, especially those for which MOE is of primary concern. The purpose of this study was to investigate the use of stress wave nondestructive evaluation techniques to sort red maple logs for the potential quality of lumber obtained from them....

Fire resistance data on exposed wood beams and columns are plentiful, but few studies have been done on exposed wood members in tension and in decks. To provide data to verify the application of a new calculation procedure, a limited series of fire resistance tests were conducted on wood members loaded in tension and on exposed wood decks.

Preservative treated wood contains components that may be toxic to non-target organisms if released into the environment in sufficient quantities. Numerous studies have been conducted to determine the rate of preservative release from treated wood and/or the extent of their subsequent accumulation in the environment. These studies have produced a wide range of results with a corresponding range of interpretations and recommendations. This paper reviews research on wood preservative leaching and environmental accumulation and discusses sources of the variability in research findings....

For decades chromated copper arsenate (CCA) was the primary preservative for treated wood used in residential construction. However, recent label changes submitted by CCA registrants will withdraw CCA from most residential applications. This action has increased interest in arsenic-free preservative systems that have been standardized by the American Wood Preservers’ Association. These include acid copper chromate (ACC), alkaline copper quat (ACQ), copper azole (CBA-A and CA-B), copper citrate (CC), copper dimethyldithiocarbamate (CDDC), and copper HDO (CX-A). All of these CCA alternatives...