Your search resulted in 1157 documents. Displaying 25 entries per page.
Quantitative assessment of the condition of field specimens
1981 - IRG/WP 2154
Suggestions for a discussion on the desirability of an extension to the existing procedure of assessment of the condition of field specimens by adding more objective, reproducible methods in order to obtain earlier and more specific information than at present on the effect of biological attack on strength and other properties of the specimens as well as the time aspect.
Field stake test assessment with the Pilodyn
1980 - IRG/WP 2136
The Pilodyn, which was originally developed to estimate the degree of soft rot in wooden poles, was thought to have potential for giving a quantitative measure of the extent or depth of decay in field test stakes. In the present work a 2-joule Pilodyn with 2.0-mm diameter pin was used in an attempt to limit depth of pin penetration (to 10-15 mm) without reducing scale sensitivity. The results show that this instrument has the potential for evaluating the degree of decay, particularly its depth, in preservative-treated test stakes exposed in "graveyard" test plots. Its major value could be in eliminating observer bias in assessing decay and in quantification of strenght loss. Its greatest application would be in the accurate detection of the depth of superficial decay, particularly in its early stages, and its further progress into test stakes.
M E Hedley, R W Naish
Assessment of wood decay in small-scale unsterile soil-bed tests
1997 - IRG/WP 97-20111
This study is concerned with the investigation of wood decay in small-scale unsterile soil-bed tests. Tests were performed with untreated heartwood samples from five hardwood species of different natural durability classes ranging from highly perishable to very resistant. Our results confirmed the critical role of soil moisture content on wood decay. The highest decay rates were observed at moisture levels close to the soil water holding capacity (WHC). With all the wood species tested, decay was retarded in soils with lower or higher moisture contents. Modification of the soil properties by addition of different amounts of an inert porous material did not affect the extent of wood decay provided that the moisture content of the modified soils was maintained, in each case, at their respective WHC. Test performed with mini-stakes (5 x 10 x 100 mm3) and smaller mini-blocks (5 x 10 x 20 mm3) showed similar levels of decay, irregardless of the test specimen size. In both cases, high mass and modulus of elasticity losses were observed in the highly perishable to moderately durable wood species after only 12-18 weeks of exposure. Based on the extent of wood decay, the small-scale soil-bed test was found to successfully discriminate between wood species in different natural durability classes.
L Machek, A M Derksen, R Sierra-Alvarez
Assessment of the Inhibition of wood decay fungi by volatile organic compounds identified from Trichoderma spp.
1999 - IRG/WP 99-10302
Previous research identified five volatile organic compounds produced by Trichoderma spp. that may be inhibitory to wood decay fungi. The effects of four of these volatile organic compounds, 2-propanone, 2-methyl-1-butanol, heptanal and octanal were tested over a range of concentrations against four selected wood decay fungi. The fungi were incubated in malt extract broth under appropriate conditions and growth was estimated by biomass production and respiration rates. The results indicated that the growth of all four fungi were affected by at least one of the compounds, usually by inhibition but in rare cases stimulation. One of the four compounds, heptanal completely inhibited the growth of three of the four fungi and significantly inhibited the growth of the fourth. The implications of these results for the biological control of wood decay fungi and future studies are discussed.
S N Humphris, R E Wheatley, A Bruce, C Payne
Nondestructive assessment of biodegradation in southern pine sapwood exposed to attack by natural populations of decay fungi and subterranean termites
1994 - IRG/WP 94-20042
Field methods for evaluating decay resistance of experimentally treated materials lack a means for quantitative measurement of residual strength. Quantitative relationships between speed of impact-induced waves travelling parallel to the grain and residual compressive strength have been demonstrated in softwood attacked by brown rot-decay fungi, but the effects of termites have not been documented. We tested southern pine sapwood stakes that were vertically inserted for one-half their length in soil in a southern pine forest in southern Mississippi. The results showed that measurement of both speed and attenuation of a reciprocating impact-induced wave will yield quantitative information on extent of total biodegradation in southern pine sapwood, independent of organism causing the damage.
R C De Groot, R J Ross, W Nelson
Limitations of the Pilodyn when assessing decay in graveyard test stakes
1982 - IRG/WP 2168
The following examination was designed to evaluate more precisely the usefulness of the Pilodyn for routine, objective assessments of the condition of field test stakes and to examine its limitations, particularly in respect to: 1.) The importance of variables other than extent of decay which may affect Pilodyn readings; 2.) Practicality of obtaining multiple readings in decayed and non-decayed regions of stakes; 3.) Correlation of visual assessment with Pilodyn readings; 4.) Optimum frequency for taking readings to obtain earlier indications of decay; 5.) Effect of repeated removals of stakes on rates of decay. Interim results have been obtained which clarify the effect of stake moisture content on Pilodyn readings.
M E Hedley
Moisture content and other tested values in. Double layer tests of different size in Lithuania and Germany
2004 - IRG/WP 04-20299
The paper presents measurement results of moisture content and the analysis of durability trial of double layer wood in variants of varying size, conducted in Girionys, Kaunas distr., Lithuania and in Hamburg, Germany. In this trial 3 sample sets of varying size, containing 25, 50 and 100 specimens, are used. The aim of this trial is to ascertain an optimal number of test specimens. The dynamics of wood moisture content and its defectiveness are estimated. The results showed, that maximum moisture content of Lithuanian trials was increasing with increasing number of specimens in one test set up. Lowest moisture content was recorded in single layer tests. The specimen remained mostly sound after half a year of outdoor exposure. Slight damage caused by basidiomycetes has been ascertained only in 5 out of 187 specimens. However mycelium growth was found on 64% of specimens. The mycelium was growing on 75-85% of lower layer samples and on 42-54% of upper layer samples in the double layer test. During the trials a newly developed stroke test proved to be promising for objective assessment of degree of decay. It will be further developed.
J Saladis, A O Rapp
Acoustic technique for assessing decay in preservative treated wood
1998 - IRG/WP 98-20138
This study investigated the suitability of vibration techniques to assess the performance of wood preservatives in ground contact. Small stakes (10 x 5 x 100 mm3) of treated and untreated Scots pine sapwood were exposed to decay in lab-scale terrestrial ecosystems. Tests were conducted using three different soils including a garden compost soil, and soils obtained from a test field and a conifer forest in Sweden. Wood decay was monitored regularly for one year by determining wood mass losses. Also, strength losses were calculated from the dynamic modulus of elasticity (MOE) of sound and exposed wood specimens as determined by vibration measurements. The results of this study show that the MOE-dynamic losses for the different preservatives and environments have a very good correlation with mass losses. The limited efficiency of some preservatives in an aggressive environment (garden compost soil) was observed. The determination of dynamic modulus of elasticity seems to offer a good basis for assessing the performance of wood preservatives in laboratory soil tests.
L Machek, M-L Edlund, R Sierra-Alvarez, H Millitz
Assessment of the Envelope Effect of Three Hot Oil Treatments: Resistance to Decay by Coniophora puteana and Postia placenta
2006 - IRG/WP 06-40344
Timber of Corsican pine (Pinus nigra var. maritima) and Norway spruce (Picea abies) was treated in hot linseed oil, rapeseed oil and a proprietary resin derived from linseed oil. The samples were immersed in oil or resin under reduced pressure at temperatures of 180°C and 200°C. Very high uptakes of the oils or resin were recorded for pine, while spruce showed lower weight percent gains, below 20%. Treated blocks were exposed to two brown rot fungi, Coniophora puteana (BAM 15) and Postia placenta (FPRL 280). The effect of using a therm-oxidatively cured resin or a drying oil (linseed) was compared with the use of the non-drying rapeseed oil. The resin treated blocks had a lower weight loss at the end of the experiment than blocks from the two oil treatments. It is believed that the polymerization of the resin immediately after treatment assists in reducing the accessibility of the timber to fungal decay. To assess the extent to which this is an envelope treatment, a simple variation on the BS EN113 test method was used to expose untreated surfaces. Sticks of timber which had been treated with the linseed oil or the resin were crosscut to expose un-cured faces on the end grain, and exposed to fungi in the same manner as the standard EN113 test. The effect of cutting open the envelope treatment was an increase in weight loss when compared to the equivalent fully sealed blocks.
M J Spear, C A S Hill, S F Curling, D Jones, M D C Hale
A preliminary note on the role of moisture absorption rate in durability assessment
2008 - IRG/WP 08-20383
The rate of moisture uptake was studied in 15 wood species using vermiculite at varying moisture levels as the exposure medium. As might be expected, moisture uptake varied widely among the species studied. While some of the more durable wood species were also resistant to moisture uptake, this was not always true. The results are discussed in relation to performance in under varying environmental exposures and the mechanisms for incorporating these data into models for predicting decay resistance in structures.
J J Morrell, L P Francis
Assessment of decay risk of airborne wood-decay fungi
2012 - IRG/WP 12-10787
The decay risk of airborne wood-decay fungi was investigated by using an air sampler. Japanese cedar disks measuring about 8 cm in diameter and 3 mm in thickness with moisture content at about 100 % were placed in a “BIOSAMP” air sampler and exposed to 1000 liters of air. Air sampling was carried out from June to September at the same sampling site in Tsukuba, Japan. The exposed disks were then incubated for 16-week in a damp container kept at 26 ± 2°C. During the incubation period, wood mass loss ranged from -15 mg to 807 mg with a mean mass loss of 244 mg. Factors affecting mass loss were explored. Wood moisture content and ratio of heartwood area proved to be significant factors. In addition, five weather factors were found to influence mean mass loss. Disks that were sampled on a cloudy day showed significantly higher mean mass loss compared to those sampled on a shiny day. Filamentous fungi grown on the disks during 16-week incubation were subcultured to investigate the relationship between the taxa of airborne fungi and the decay risk. The subcultured fungi were isolated and DNA extracted from each isolate was amplified with the primers ITS4/ITS5. The DNA sequences of the amplified products were determined and compared to the sequence data of GenBank to determine the species or genus according to a BLAST search. This search revealed that the isolate consisted of 5 major taxa, namely Bjerkandera sp., Phanerochaete sp. (A), Phanerochaete sp. (B), Polyporales sp. Polyporus arcularius, and 6 minor ones. Statistical analysis revealed that the disks attached by Phanerochaete spp. or Polyporales sp. showed higher mean mass loss. It is concluded that, under these experimental conditions, related species of P. sordida play an important role in increasing the decay risk caused by airborne wood-decay fungi.
I Momohara, Y Ota, K Sotome, T Nishimura
Assessment of Boracol 200RH (FrameSaver) as a remedial treatment to control decay in pre-decayed model timber frame units
2010 - IRG/WP 10-30529
Model timber frame units constructed from untreated radiata pine were pre-wetted to approximately 40% moisture content and inoculated with Coniophora puteana and Oligoporus placenta. Units were transferred to a controlled environment room maintained at 25°C and 95% RH for 7 and 10 weeks to allow two levels of decay to become established in units. Following pre-decay, units were disassembled, cleaned of adherent mycelium and superficially dried. They then received either one brush coat of Boracol 200RH (7 weeks pre-decay) or 2 brush coats (10 weeks pre-decay) and were re-inoculated with the same decay fungi. Units were periodically assessed for decay and at 239 or 255 weeks exposure, representative units were dissected and assessed for internal decay. Samples were spot tested for the presence of boron and cross-sections and cores analysed for boron. There was very little, if any, progression of internal decay following application of Boracol to frames with either 7 week or 10 week pre-decay periods. Spot tests indicated that boron had diffused through the cross-section of all unit components. This was confirmed by preservative analyses. Residual boron core retention levels in most components exceeded the toxic threshold for boric acid, which presumably accounts for lack of spread of decay following Boracol 200RH application.
Mick Hedley, Dave Page, Jackie van der Waals
In-ground durability of wood-based products – Comparative assessment of graveyard field tests and terrestrial microcosms
2014 - IRG/WP 14-20538
Traditionally wood durability and the effectiveness of wood preservatives are determined in so-called graveyard tests (according to EN 252 or AWPA E7). For laboratory testing, terrestrial microcosms (TMC) can serve as an alternative. Both tests have been applied for different types of wood-based materials, preservative treated, modified and unmodified wood. However, the usability of laboratory results for predicting the performance of wood products under field conditions has been discussed controversially for a long time. With the purpose of profounder understanding, a comprehensive test was set up to compare re-sults from different laboratory and field tests considering the full range of wood based products. In total 34 materials (11 native softwoods, 5 native hardwoods, furfurylated, acetylated and thermally modified timber as well as different preservative treated timbers) have been exposed in ground at the test sites Borås, Sweden, and Hannover, Germany. Furthermore lab tests with TMCs have been conducted. Therefore an active compost soil producing high soft rot decay was used as well as the field soil from the two test sites to allow direct comparison. The mass loss obtained in the TMCs differed drastically whereby compost soil showed the high-est decay activity. Generally, the obtained mass loss was lower in the Borås soil compared to the soil from Hannover. However, this was not confirmed by the decay progress observed in the Bo-rås field, which was approximately equal to the activity in the Hannover field. Furthermore, some materials suffered from brown rot decay in the field which was absent in the TMCs, where moisture conditions were unfavourable for brown rot fungi. Different indicators and statistical measures were assessed with respect to their potential for pre-dicting the outdoor performance of the various wood-based materials. In spite of a general com-pliance between lab and preliminary field test results, a remarkable number of discrepancies pointed on the need for field tests representing all relevant types of decay.
A Soetbeer, L Meyer, C Brischke, P Larsson-Brelid, J Jermer
A review of the analytical methods used in determining the decay resistance of heat treated wood
2015 - IRG/WP 15-40690
Heat treatment as a wood process is increasingly used because of its non-biocide behaviour and its low environmental impact. This sort of treatment is based on biopolymer chemical degradation by heat transfer. This process improves mainly the dimensional stability and the decay resistance of wood. Wood becomes darker after this type of treatment and thus gives it an aesthetic appearance. These improvements come at the expense of wood mechanical properties which are weakened. These last modifications have been subsequently extensively studied and previous researches have shown that new heat treated wood properties are correlated to heat treatment conditions and to the nature of industrial process used. Nowadays, recent works are focus on the knowledge improvement of wood thermal degradation reaction mechanisms, modelling, quality prediction and quality control. Moreover, it remains also important to develop inexpensive, fast and nondestructive industrial methods to control the process and predict heat-treated wood quality. This review therefore describes recent studies and synthesizes the major publications which have been conducted on better understanding on wood thermal modification and on the development of control and prediction ways on new feature brought to heat treated wood.
K Candelier, M-F Thévenon, A Pétrissans, S Dumarçay, P Gérardin, M Pétrissans
Assessment of the biological durability of wood treated with organosilicon compounds
2016 - IRG/WP 16-30685
The European wood construction market is in need of environmentally friendly wood-based products whose service life meets the expectations of end users. Non-biocidal silicon-based water repellents, which can be applied to different materials, help minimize their vulnerability/susceptibility to liquid water. Consequently, they have the potential of increasing wood’s resistance against decay fungi by reducing their ability to absorb water. Moreover, by filling the pores of wood, they may reduce its vulnerability to wood-boring insects and thus improve its durability. In order to determine their suitability as wood protectors, three silicon-based water repellents were applied at different concentrations to samples of Scots pine, beech and oak. The application was either superficial (dipping) or by deep (vacuum impregnation). Durability tests were then performed in order to determine the resistance of the treated wood samples against moulds, blue stain and basidiomycete decay fungi, as well as against Reticulitermes subterranean termites. Additionally, eco-toxicological tests were run in order to select the product which had the least environmental impact. The results demonstrate that the three tested organosilicons exhibit different levels of toxicity and improvement of the resistance of the tested wood species against biological threats. The anti-fungal resistance is lower than that provided by traditional biocidal wood-preservatives, but it is still adequate in applications where short-to-average service-life is acceptable and where maintenance and/or replacement is possible. Termite behaviour and feeding preferences in situations where choosing between treated and untreated wood was possible demonstrated that insects tend to avoid consuming wood specimens impregnated with organosilicons. Wood-based materials with levels of biological resistance which are intermediate between wood’s natural (inherent) resistance and that improved with the help of biocides as well as wood-protection products and processes which allow reaching these levels should be appreciated more. They increase the range of possible end-uses for wooden commodities made of European non-durable wood species such as Scots pine and beech both with regard to the material’s properties and its expected performance.
M Kutnik, M Montibus, S Derocker, S Salivati, J-P Lecomte
Assessment of the quality and lifetime of wooden pile foundations
2017 - IRG/WP 17-10883
The development of wooden pile foundations started centuries ago and enable man to build and live in strategic and fertile areas. Although the building methods, the building materials and the building regulations chanced especially over the last decades, worldwide wooden pile foundations still fulfil their function to support above ground constructions of which many belong to our cultural heritage. In the Netherlands wooden foundations are a national bench mark and Amsterdam is often regarded as the City on wooden piles. The pile population in service is estimated on 25 million and as they are carrying many ordinary family houses and water building constructions their importance is far above building history. The behaviour of wood in the soil and the special threats for pile foundations asked for an adapted method in order to assess the actual and future status of these underground constructions. This paper describes a method quantifying the actual and future stability taking in to account the special behaviour of wood in constructions in the ground. This method was developed in the last decades in the Netherlands by a multidisciplinary group of researchers.
R W W M Klaassen, A Jorissen, H Keijer
Preliminary Investigation into the Natural Decay Resistance of Nigerian Grown Hevea brasiliensis and Mitragyna ciliata wood to Phanerochaete chrysosporium White-Rot Fungus
2018 - IRG/WP 18-10919
Wood is an important and versatile structural building material that finds applications in numerous uses. However, wood is also a biological material vulnerable to degradation by microbial activities; this is especially true in the tropics. Following the scarcity of highly durable species from our natural forests and the introduction of so many lesser used/durable wood species into the booming timber market, the natural durability of timber materials available in the market becomes of critical importance with respect to appropriate material selection, as well as the nature and extent of processing required to avoid deterioration of such wood in service by biodeteriorating agents. In this study, preliminary investigation into the natural decay resistance of Nigerian grown Mitragyna ciliata and Hevea brasiliensis wood to Phanerochaete chrysosporium white-rot fungus was carried out. Surfaces of Mitragyna ciliata and Hevea brasiliensis wood samples from the top, middle and base stem height positions of the two wood species were exposed to P. chrysosporium in an accelerated laboratory decay test according to ASTM D-2017 for sixteen weeks. Preliminary results indicate that both the M. ciliata and H. brasiliensis wood species wood species just after two weeks are susceptible to attack by the P. chrysosporium white-rot fungi, as the test blocks were visibly covered with fungus mycelium. However, the degree of mass loss as a result of the fungal attack and the classification of the wood samples of the two species based on their natural resistance are yet to be ascertained and will be made available in a full paper that will be sent not later than the last week of March, 2018.
J M Owoyemi, U O Emmanuel
Visual assessment of longitudinal wheel timbers and assessing the feasibility of extending wheel timber service life in the UK railway network
2019 - IRG/WP 19-20651
Timber has been a versatile building material for centuries and during the start of the Railway Age in the nineteenth century it was in considerable demand for use in the railway network, particularly bridge building. Timber is still in service and widely used throughout the UK railway network. The resilience and favourable strength to weight ratio and its relative ease of fabrication make it an attractive material for use in the network. Longitudinal wheel timbers are used extensively to carry track in situations where it is desirable to reduce the weight of bridges and in locations where the depth of the structure prevents the use of ballasted track. Most wheel timbers in the UK comprise creosoted Douglas fir, southern pine or European redwood and to a lesser extent, naturally durable tropical hardwoods. Wheel timbers installed post-2003 tend to comprise softwoods treated with aqueous borne ‘copper/organic’ formulations. Concerns about the effects of fungal decay and non-standardised inspection regimes are problematic. Managing the network is complex and imposes high and often conflicting demands on infrastructure asset managers. Effective asset management within a safety critical sector is an essential discipline and it is the variable nature of timber that presents significant management challenges. This paper summarises a possible strategy to improve the examination and assessment of wheel timbers and assesses the feasibility of extending service life of wheel timbers exhibiting signs of localised decay. This approach may deliver more effective asset management of timber assets.
J R Williams
Identification of Antifungal Compounds in Konjac Flying Powder and Assessment against Wood Decay Fungi
2019 - IRG/WP 19-30737
The antifungal activity of konjac (Amorphophallus rivieri) flying powder (a by-product produced during mechanical processing of konjac flour) ethanol extract was evaluated against wood decay fungi in culture. Compounds associated with antifungal activity in the extracts were isolated and purified by silica gel column chromatography. The antifungal active fractions were identified by ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-QE-MS). The ethanol extract showed good activity against the white-rot fungus, Trametes versicolor, and the brown-rot fungus, Gloeophyllum trabeum. The antifungal active fractions were mainly composed of organic acids and plant essential oils. Salicylic acid, 2,4,6-trichlorophenol and vanillin were presented in the active fractions. The preliminary results indicate that konjac extracts have potential as natural wood protectants. Further tests in wood are planned.
Z Bi, F Yang, Y Lei, J J Morrell, L Yan
Danish wood preservatives approval system with special focus on assessment of the environmental risks associated with industrial wood preservatives
2001 - IRG/WP 01-50166-01
The following is a description of the procedure used by the Danish Environmental Protection Agency to assess the environmental risks associated with preservatives used in the pressure impregnation of wood. The risk assessment covers issues considered to be of significance for the environment and which are adequately documented so as to allow an assessment. Such issues are persistence and mobility in soils, bioaccumulation and the impact on aquatic and terrestrial organisms. Unless required in special circumstances, the assessment does not apply to birds and mammals as the normal use of preservative treated wood is not expected to involve any noteworthy exposure of these groups. Approval of wood preservatives will be based on a general assessment of the environmental risk associated with the normal use of wood treated with the preservative in a realistic worst case situation. The assessment may address other aspects such as disposal and total life cycle.
Programme section 2, Test methodology and assessment
1997 - IRG/WP 97-20126
Confocal laser scanning microscopy of a novel decay in preservative treated radiata pine in wet acidic soils
1997 - IRG/WP 97-10215
Light microscopy of radiata pine (Pinus radiata D. Don) field test stakes (20x20x500mm3) exposed in wet acidic (pH 3-4) soil for 12 - 24 months showed predominance of an unusual type of decay characte-rised by tunnelling attack of wood cell walls. After two years decay was moderate to severe in wood treated to ground contact CCA specifications and also equivalent retentions of creosote, and a number of new generation preservatives. Relative to other New Zealand temperate test sites and also an Australian tropical site, the New Zealand acidic soil test site was very aggressive. Correlative scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to elucidate the micromorphology of this attack. Tunnels of diameter 0.2-5 µm were present throughout all layers of the cell wall, and their orientation was not related to cellulose microfibril orientation. They also showed no preference for particular cell wall layers, indicating a lignin degrading capability. CLSM images showed that living, connecting fungal hyphae were present in the cell lumina and tunnels. This type of attack was predominant in wood that was highly saturated with water whereas wood that was less moist was predominantly attacked by classical white rot. Ongoing isolation and incubation studies in conjunction with further microscopy should enable identification of the fungal species involved.
R N Wakeling, Ying Xiao, A P Singh
Effect of acetylation on decay resistance of wood against brown-rot, white-rot and soft-rot fungi
1989 - IRG/WP 3540
Effect of acetylation on decay resistance of wood was investigated using wood blocks of Cryptomeria japonica, Pinus densiflora, Albizia falcata and Fagus crenata. Blocks were treated with uncatalyzed acetic anhydride for different lengths of time and exposed to Tyromyces palustris, Serpula lacrymans, Coriolus versicolor and unsterilized soil. The action of OH-radical on acetylated wood was also examined using Fenton's reagent. The enhancement of decay resistance by acetylation was revealed clearly for all cases of exposures but varying with fungal and wood species used. For a brown-rot fungus Tyromyces palustris, the weight loss reached almost nil in all woods at 20 WPG (weight percent gain) of acetylation, after the striking decrease from 10 to 15 WPG. For a white-rot fungus Coriolus versicolor, it was counted until 12-15 WPG in the perishable hardwoods used, but not in a softwood Cryptomeria japonica, even at 6 WPG. In cases of another brown-rotter Serpula lacrymans and soil burial, effect of acetylation was intermediate between Tyromyces palustris and Coriolus versicolor. Anti-degradation mechanism by acetylation was discussed, from these weight loss - weight gain relationships, and the IR-and 13C-NMR spectral analyses of fungus-exposed wood.
M Takahashi, Y Imamura, M Tanahashi
Questionnaire - Fungal decay types
1985 - IRG/WP 1265
JWPA method for testing effectiveness of surface coatings with preservatives against decay fungi
1981 - IRG/WP 2164
In 1979 JWPA established a new method for testing effectiveness of surface coatings in accordance with practical use of preservative-treated lumber. Comparing the new testing method with JIS A 9302, a few new trials - size of wood specimen, weathering procedure, and decay-test procedure - are incorporated.