Your search resulted in 12 documents.
Thirty-four year test of on-site preservative treatments to control decay in wood above ground
1993 - IRG/WP 93-30015
This research was initiated in 1958 to investigate efficacy of various preservatives and treating methods for new lumber going into exterior structures of buildings. Post-rail units (2x4 inches) constructed of Southern Pine sapwood, Douglas-fir heartwood, and mill run western hemlock were dip- or brush-treated before or after assembly. Units were trested with pentachlorophenol in various petroleum...
T L Highley, T C Scheffer
Climate indices at work: Above ground decay L-joint tests (EN 330 and AWPA E9) at two sites 12000 km apart and with Scheffer climate indices of 60-65 and 300-330
1996 - IRG/WP 96-20095
Matched sets of Scots pine sapwood (Pinus sylvestris) L-joints were exposed above ground at two field sites for approximately five years. One site, at Garston, Watford, UK has a climate index between 60 and 65 while the other, close to Hilo, HI, USA has an index between 300 and 330. The joints were treated with a range of organic solvent treatments applied either by three minute dip immersion or b...
A F Preston, K J Archer, D M Roberts, J K Carey, A F Bravery
A bioassay for appraising preservative protection of wood above ground
1978 - IRG/WP 2124
A bioassay, using the mold fungus Aspergillus niger, gave results that were correlated with amounts of pentachlorophenol and tributyltin oxide in pine sapwood treated with solutions ranging in strength from 0.016 or below to 5%. Limited bioassay estimates of penta in commercially treated millwork corresponded to estimates by lime ignition. The assay fungus exhibited somewhat greater tolerance of t...
T C Scheffer, L Gollob
Relative merits of laboratory and field tests for assessing wood decay resistance
1993 - IRG/WP 93-20009
Laboratory and field trials have long been employed for assessing natural durability of a variety of wood species, but there is a continuing debate concerning the relative merits of approach. While laboratory tests provide carefully controlled conditions for decay, they are often criticized for being too artificial to produce meaningful results. Conversely, field trials often vary widely between t...
T C Scheffer, J J Morrell
After 18 years, preservative dipping and brush treating continue to provide protection to shingles of western wood species
1997 - IRG/WP 97-30156
The presence of residual preservation in dip-treated and brush-treated shingles of various species from the western United States was assessed 18 years after installation using Aspergillus bioassays. The performance of western redcedar (Thuja plicata) was compared to western hemlock (Tsuga heterophylla), sugar pine (Pinus lambertiana) and western larch (Larix occidentalis). Untreated shingles of a...
T C Scheffer, D J Miller, J J Morrell
A New Decay Hazard Map for North America Using the Scheffer Index
2008 - IRG/WP 08-10672
Wood decay experts in the USA and Canada use the Scheffer Index for above-ground wood decay potential to decide among design and treatment options to ensure the durability of wood construction. This paper provides an updated North American decay hazard map and includes data on Central America. Index values calculated from recent climate data are higher than published values due to directional or c...
P I Morris, J Wang
Decay Hazard Classifications in China for Exterior Above-Ground Wood
2007 - IRG/WP 07-20357
A decay hazard map for exterior above-ground wood structures is presented based on Scheffer’s Climate Index, with the major purpose of promoting awareness for proper protection of wood structures in different locations in China. A very large area in the South, including southern Yunnan, most of Sichuan Province and Chongqing, and part of Hunan, Hubei, Anhui, Jiangxi, and Zhejiang, as well as all...
J Wang, X Wu, M Jiang, P I Morris
To decay or not to decay: An accelerated field test of the validity of the Scheffer index
2008 - IRG/WP 08-20392
The Scheffer Index was introduced in 1971 to predict the relative decay hazard of untreated wood exposed above-ground. Precipitation and temperature parameters are used in the calculation. A higher Scheffer Index value implies a greater risk of decay. An accelerated 18-month study using seven field sites with Scheffer Indices ranging from 35 to 400 and two wood types (Populus tremuloides and Pi...
G M Larkin, P E Laks
Field testing in Colombia: Three years of evaluations and experiences
2008 - IRG/WP 08-20394
Two field test sites have been established in Colombia for the evaluation of fungal and termite resistance of treated wood. The combination of elevated temperature, high and stable humidity and high rainfall at the two test sites accelerates microbial and insect activity (Scheffer, 1971; Thornton et al, 1994; Freitag et al, 1995). Tests established include above ground termite tests, ground contac...
Y Cabrera, A Preston
Decay hazard mapping for Europe
2011 - IRG/WP 11-20463
In this study, two different dose-response models for above-ground decay as well as a model transferring macro climate data to wood climate data are presented. The models base on data from field trials, which had been conducted at 28 European test sites, and were used to calculate the relative risk for decay caused by climate variability in Europe. The two dose-response models give coherent result...
C Brischke, E Frühwald Hansson, D Kavurmaci, S Thelandersson
Observed and projected changes in the climate based decay hazard of timber in the United Kingdom
2020 - IRG/WP 20-20665
The risk of microbiological attack on wood is determined by both material and climatic factors and indeed the hazard for a component is based on its intrinsic durability and the conditions in which it is used. The use of wood and organic materials in construction is increasing but ultimately all these materials will be susceptible to microbiological attack. The Scheffer Climate index applies clima...
S F Curling, G A Ormondroyd
Modelling decay rates of timber exposed above ground on four different continents
2020 - IRG/WP 20-20670
Durability performance data from an international decking trial were analysed to explore relationships with climate variables, particularly those related to temperature and rainfall. Matched decking samples of slash pine (Pinus elliottii) sapwood and heartwood, spotted gum (Corymbia citriodora), Norway spruce (Picea abies) and Scots pine sapwood (Pinus sylvestris) were exposed to the weather above...
L P Francis, J J Morrell, C Brischke, P B Van Niekerk, J Norton