Your search resulted in 56 documents. Displaying 25 entries per page.
Study on the Effects of Flame Retardant in Dancheong for Korea Wooden Cultural Heritage
2015 - IRG/WP 15-40692
This study identifies the effect of the agent depending on environment change and conducted basic study to prepare criteria for stable application. Dancheong sample, which is similar to wooden cultural heritage, was manufactured to study the effect of the agent on dancheong. Regular observation on the samples located in inland and shoreline area in the country detected visible phenomena. Whitening, melting, peeling were observed, especially whitening was most frequently observed. This can be interpreted that whitening occurs when calcium carbonate reacts to phosphate system, a main ingredient of flame-proofing agent.
Hwa Soo Lee, So Jung Lee, Gyu Seong Han, Yong Jae Chung
Evaluation of the fire retardant efficacy and leach resistance of an amino resin fire retardant - Preliminary report
1983 - IRG/WP 3260
The Early Fire Hazard Indices of untreated Pinus radiata were determined by testing to Australian Standard 1530, Part 3 - 1976. Differences in the performance of heartwood and sapwood were noted, with heartwood samples giving higher Ignitability, Heat Evolved and Spread of Flame indices. The treatability of Pinus radiata with Pyrogard H was assessed, and backsawn sapwood treated more effectively than all other combinations of direction of cut and sapwood/heartwood. Treatment of kiln dried DAR Pinus radiata with Pyrogard H did not produce dimensional changes of practical significance. This factor, plus a high concentration gradient of retardant in the treated timber, make it an ideal treatment for fully machined and profiled Pinus radiata. The leach resistance of the retardant was assessed. A greater percentage of phosphorus than nitrogen was leached, but the retardant remaining after leaching conferred similar protection to the unleached material at equivalent rententions. Pyrogard H is an effective leach resistant fire retardant for Pinus radiata.
W D Gardner, P N Alexiou, P Lind, D Butler
Wood-leather panels – A biological, fire retardant building material
2012 - IRG/WP 12-40615
The poor flame retardant properties of wood-based products are among the severest obstacles, hindering its use in the commercial building sector. Recently, some attempts to improve the fire properties, relying on inflammable salts or reactive halogen compounds, have been presented, although they either cause problems with machining or embody harmful compounds (halogen derivates). In this paper, the fire retardant properties of a novel material, wood-leather panels, are determined by the use of flame tests in a furnace according to ÖNORM EN ISO 1363:2011. The specimens were evaluated according to integrity and surface temperature. For the test specimens, wet white (WW) and wet blue (WB) leather shavings, with varying contents were used. The main finding is that both, panels containing WW and WB leather shavings, show properties superior to current flame-retardant medium density fibre boards, MDF B1,s2-d0. An optimum was found here at a leather content of 50%. In order to describe this behaviour towards fire in further detail, the calorific value of the material as well as the thermal conductivity were determined. As the leather panels produce a foam-like structure during the fire treatment, it is assumed, that this is caused by the exhaust of gases, leading to decreased temperature flow through the specimen, resulting in the observed properties. It can be concluded that the panels show superior fire retardant properties, compared to commonly available flame retardant material. Therefore further research in this field is proposed, with the aim to produce a certified product.
S Wieland, U Stöckl, T Grünewald, S Ostrowski, A Petutschnigg
The whitening cause of Korean wooden heritage by flame retardant treatment
2015 - IRG/WP 15-20560
Korean wooden heritage used to treat by flame retardants in order to protect fire. There are 2 types flame retardant using for wooden heritage. These flame retardants treatment are basic measure that apply to wooden heritage along with other fire protection. The flame retardants cause white stains by reacting with Korean traditional wood painting (Dancheong) and increase wood humidity. The Korean government had discontinued use of flame retardants on the wooden cultural assets because of this whiteness phenomenon. This study was carried out to find out the cause of white stains by flame retardants treatment. The reaction of pigment and flame retardants was analyzed.
Jin Qyu Kim, Gyu-Seong Han, Yong Jae Chung, Hwa Soo Lee, Dong Won Son
Experimental Measurements of Fire Retardants on Plywood at Fire Test
2015 - IRG/WP 15-40709
The use and development of wood composite materials increased in the past few years. However, in Brazil there are some restrictions on these products regarding their use, since it could be considered a potential risk at a fire situation. Thus, becomes evident the need for researches aiming to fit these in safety standards. This study aims to evaluate the efficiency of two new fire retardant products produced by a Brazilian industry. Tests were performed in plywood panels of Pinus spp previously immersed, varying the products concentrations and compared with untreated samples. The test used to evaluate the flame spread in a panel was the modified Schlyter test. The product in question was proved efficient, before and after shutting off the burner. Comparing with the panels without treatment, there was a decrease of 400% of the height of the flame spread on the treated ones.
G C A Martins, L A Marcolin, J M Vidal, C Calil Jr
The Study of the Preparation of Overlaid MDF with the Flame Retardant Impregnated Paper
2018 - IRG/WP 18-40848
The preparation of overlaid medium density fiberboard (MDF) was studied. The flame retardant impregnated papers (FRIP) were overlaid on the surface of the MDF for the fire protection. The results showed that: 1) The production of the FRIP was based on the technology of melamine-impregnated paper, which required the viscosity of the impregnated resin lower than 20s. However, with the addition of the pentaerythritol (PER), one component of the flame retardant, the viscosity of the resin increased rapidly because of H-bonds. The viscosity of the resin was kept low by addition of urea. 2) The curing time of the resin was adjusted by the ratio of F/(M+U) and the addition of ammonium polyphosphate. 3) The surface bond strength of the FRIP met the standard requirements, which was influenced by the pressing conditions. 4) The flame retardant was concentrated on the surface of wood materials with the FRIP. The efficiency of the flame retardant was enhanced significantly, and better than that of the physical mixture and impregnation, and the cost was reduced.
W Qu, M Wu, Y-Z Wu
Development of Wooden Fireproof Structures for Mid- and High-rise Buildings in Japan
2021 - IRG/WP 21-30757
When constructing a mid-to-high-rise building more than 4 stories in general in Japan, it is necessary to have a fireproof structure stipulated by the Building Standard Law. The performance required as a fireproof structure in Japan is generally stricter than in other countries, and it is required to be structurally sound after a fire even without fire extinguishing activities. In order to satisfy this requirement, the structural member must continue to support the load during the event of a fire. In the case of wooden structure, this means that the combustion should be eliminated spontaneously, and the charring of load support portion is not allowed. Under these conditions, many wooden fireproof structures have already been developed, and wooden buildings are actually being constructed widely. The method of making a wooden fireproof structure is roughly divided into (1) a “inorganic covering type” with gypsum board and (2) a “flame die out type” using fire-retardant treated wood or heat absorbing material. In this report, we will introduce these wood-based fireproof structures, as well as the fireproof structure of “flame die out type” developed by our research group, and the cases where the wooden fireproof structure has been actually applied to various buildings.
D Kamikawa, M Harada, H Matsunaga, R Takase, N Hattori, Keisuke Ando, M Miyabayashi
The biostatic effect of copper on decay of fire retardant-treated mining timber
1991 - IRG/WP 1507
Blocks of Eucalyptus grandis were treated with 20kg/m³ ammonium sulphate as fire retardant and challenged with Coriolus versicolor. Replicates were soil buried. A second set of blocks was treated with retardant and copper at 6.6 kg/m³ (ie 1% w/w), and challenged similarly. After 8 weeks weight losses produced by Coriolus versicolor in untreated, retardant treated and copper supplemented blocks were 45, 25, and 0% respectively, and corresponding weight losses in soil were 27, 25 and 10%. These results, and electronmicroscopical observations, showed conclusively that Eucalyptus grandis treated with fire retardant was rapidly decayed, and that copper inhibited such decay.
G D Shelver, E A Shelver, A A W Baecker
Fire resistance of Alder wood treated with some chemicals.
Part II. Effect of Other Chemicals on the Combustion Properties
2002 - IRG/WP 02-40235
Samples from alder wood (Alnus glutinosa (L.) Gaertn. subsp. barbata (C.A.Mey) Yalt.) were impregnated according to ASTM D 1413-88 with boron compounds (boric acid, borax, sodium perborate), vinyl monomers (styrene, methyl methacrylate), Tanalith-CBC, Phosphoric acid, Vacsol, Immersol, Polyethylene glycole (PEG-400) and their mixed solutions of chemicals in order to determine their combustion properties. The results indicated that inorganic boron compounds with aqueous solutions were very effective as fire retardant and reduced burning of some vinyl monomers at some extent such as styrene and methylmetacrylate when used as a secondary treatment chemical polimerized later on wood structure and phosphoric acid was also showed fire-reterdancy. Further studies are suggested on boron-vinyl monomers, and boric acid+borax with different concentrations by physical and chemical interactions in terms of fire reterdancy.
A Temiz, Ü C Yildiz
The yeast Pichia sp. As a short-term biological control agent to fungal spoilage of sawn softwood timber
2000 - IRG/WP 00-10362
Previous work has found isolates of the yeast Pichia to be a successful biological control agent toward moulding of fruits. An isolate was tested for the ability to protect sapwood of Pinus sylvestris timber against visual degrade by surface growth of moulds and staining fungi. Successful protection of autoclaved wood sprayed with a mixture of common wood moulding fungi was achieved when the yeast was applied at a rate of 6 x 10 8 cells/cm2. Yeast cells were sprayed onto the wood blocks at the same time as the fungi and blocks were incubated under conditions favourable to fungal development for 15 and 25 days before assessment using a visual scale. Limitation of the disfigurement of green wood required a similar cell application rate. Protection of blocks sprayed with Ophiostomatoid staining fungi following sterilisation required a lower concentration of yeast cells (2 x 10 6 cells/cm2). Survival and reproduction of Pichia cells on sterilised wood blocks was also determined across a range of relative humidity and temperature conditions previously found to support development of wood moulding and staining fungi. Following 16 weeks incubation at temperatures of 8-25°C at relative humidity 93-100%, between 46 and 473% of the number of colony forming units applied to the wood were recovered. Maximum increase in viable yeast cell count on wood blocks occurred at 100% relative humidity and 15°C.
C Payne, H J Staines, A Bruce
Preliminary field and laboratory findings regarding the efficacy of a novel anti-marine wood borer agent
2000 - IRG/WP 00-10380
Blocks of sapwood of Pinus nigra were treated by vacuum impregnation with Biocide A to retentions of 0.5, 1 and 2 kg m-3. Similar blocks were vacuum-pressure impregnated with CCA to retentions of 2, 24 and 38kg m-3. The blocks were exposed subtidally in Mourilyan Harbour (Queensland, Australia). After 5 and 10 months exposure, blocks were removed, examined for superficial signs of attack by wood borers and X-rayed to reveal any teredinid tunnels. Higher retentions of both types of preservative prevented borer attack over the first 5-month period. After 10 months, all 3 loadings of Biocide A-treated samples had been moderately attacked by teredinids. Control blocks were heavily attacked with up to 0.23 ± 0.09 borers cm-2 after 5 months and 0.42 ± 0.07 borers cm-2 after 10 months. Slivers of wood from other blocks treated to the same preservative retentions were subjected to 6 days of leaching in running seawater. Individual Limnoria lignorum were placed, with a wood sliver in 6 ml of seawater in the cells of a repli-dish. The repli-dishes were maintained at 17°C and water was changed every 3 days. Faecal pellet production was monitored over a 1-week period. Pellet production was highest on untreated wood and lowest at the 2kg m-3 loading of Biocide A -treated wood. L.lignorum in contact with these shavings were less active and became covered with debris, whereas those in contact with CCA-treated wood and untreated wood continued to be active and remained free from debris.
A Praël, S M Cragg, R A Eaton
Copper binding capacity of modified wood flour
1992 - IRG/WP 92-3709
Wood flour was modified by reaction with oxidising agents and CCA preservative. The copper chromium and arsenic were removed from the CCA treated wood flour by an acid leaching procedure. The modified wood flours were allowed to react with copper acetate solution and the level of copper fixation achieved was determined. The modified wood flours had greater affinity for copper ions present in solution than unmodified wood flour.
N C Milowych, W B Banks, J A Cornfield
Chapter 6 - Preservatives of bamboo
2007 - IRG/WP 07-10635-06
Almost all currently available oil-borne, water-borne and compound types of preservatives suitable for the preservation of bamboo or wood have been described along with their classifications, applications, formulations, merits and demerits, history of invention or discovery and development. The preservatives suitable for wood are also considered suitable for bamboo.
A K Lahiry
Serviceability modeling-Predicting and extending the useful service life of FRT-plywood roof sheathing
2000 - IRG/WP 00-20210
One of the most, if not the most, efficient methods of extending our existing forest resource is to prolong the service life of wood currently in-service by using those existing structures to meet our future needs (Hamilton and Winandy 1998). It is currently estimated that over 7 x 109 m3 (3 trillion bd. ft) of wood is currently in service within the United States of America (PATH 1999). Research programs throughout North America are increasingly focusing on understanding and defining the salient issues of wood durability and by maintaining and extending the serviceability of these existing wood structures. This report presents the findings and implications of a major 10-year research program carried on at the U.S. Forest Products Laboratory. This research program developed serviceability models for fire-retardant (FR)-treated plywood roof sheathing exposed to elevated in-service temperatures and experiencing thermal degrade. FR-treated plywood roof sheathing is often required by U.S. Building Codes in roof systems for multifamily dwellings having common property walls. This 10-year research program found many important facts. Qualitatively, the mechanism of thermal degrade in FR-treated plywood was acid-hydrolysis. The magnitude of strength loss could be cumulatively related to FR chemistry, thermal exposure during pre-treatment, treatment, and post-treatment processing and in-service exposure. The effects of FR chemistry could be mitigated by use of pH buffers. The strength effects were similar for many levels of plywood quality. Quantitatively, a kinetics-based approach could be used to predict strength loss based on its time-temperature history. This research program then developed models with which to assess current condition, predict future hazard based on past service life, and then predict residual serviceability of untreated and FR-treated plywood used as structural roof sheathing. Each of these findings is briefly described in this report. There are many opportunities for extending the useful service life of wood by better maintenance, remedial treatment, or enhanced serviceability assessment to predict both residual strength and residual utility. Results of research programs such as this can be used to extend service-life by providing the engineer with a estimate of residual serviceability and thereby avoiding premature removal. Many of the concepts employed in the development of these FR-plywood serviceability models are directly applicable to the development of predictive durability models for wood as affected by decay. When such a durability-based service-life model is developed, that serviceability model will aid building code officials, regulators, contractors, and engineers in determining replacement time schedules for wood undergoing biological attack.
J E Winandy
Bending Properties of FRT OSB
2012 - IRG/WP 12-40600
Fire retardant treated (FRT) oriented strandboard (OSB) and plywood of different widths were tested in static bending to determine width effects. Results were consistent with previous width effect studies and showed that increasing specimen width results in a decrease in sample MOR properties among all the sample groups tested in this study. Increasing sample width for OSB samples leads to more consistent MOR and MOE values. FRT plywood has a better width factor value than the two OSB sample groups tested in this study.
J M Hill, H M Barnes, S Q Shi
Utilization of plasma treatments in the field of wood protection
2021 - IRG/WP 21-40912
Plasma treatments have been used for modification of surfaces of wood and wood-based materials for some decades and solutions were developed to apply it for wood protection. This contribution aims to present the background, introduce the available plasma technology, and to give an overview on the typical applications and benefits.
S Dahle, H Militz
Monitoring the potential biological control agent Cartapip
2000 - IRG/WP 00-10365
Attempts to biocontrol woodstain caused by Ophiostoma species led to the development of an O. piliferum colorless mutant - Cartapip (AgraSoL). The mutant's ability to prevent sapstain of stored logs and lumber is tested in a variety of field trials in Germany, England, Canada and New Zealand. To carry out biocontrol field trials, users have to obtain a permit from a regulatory agency and have to develop specific detection tools for monitoring the growth and spatial distribution of the control agent in the field. In addition, information on the genetic relatedness of the biocontrol agent and the natural population has to be generated to facilitate the registration of the product. Using two different media and an incubation temperature optimal for Cartapip but slightly too high for sapstain fungi and molds, the presence of Cartapip could be monitored in a field trial. To examine the genetic relatedness of Cartapip and the wild type O. piliferum strains, the genetic variation of the ribosomal region and the b-tubulin gene was determined. Both the 18S and the 26S rDNA regions were quite conserved among the O. piliferum strains and Cartapip. Meanwhile, genetic variation was observed in the b-tubulin gene, which led to the design of a Cartapip-specific PCR-primer set. The usefulness of a specific enzyme-cutting site (SpeI) to monitor Cartapip was also tested. The specific primer and the restriction enzyme were able to differentiate Cartapip from the most O. piliferum strains tested. Finally the application of both monitoring strategies on wood was shown.
S Schröder, K Sterfinger, Seong Hwan Kim, C Breuil
Laboratory and field evaluations of a novel formulation, BAM as an anti-sapstain agent
1991 - IRG/WP 3639
A novel anti-sapstain formulation, BAM, consisting of 2-(thiocyanomethylthio) benzothiazole (TCMTB) and methylene bis thiocyanate (MBT) was evaluated for ist anti-sapstain performance in the laboratory and in the field as well. BAM proved effective in controlling the growth of molds and a sapstaining fungus in the standardized Japan Wood Preserving Association (JWPA) tests. All the test fungi could not show any growth on the boards treated at 1% (100 times dilution), and at 0.67% of BAM only Gliocladium virens grew very slightly. In the field tests, BAM maintained good protection for 1.5 months when freshly sawn pine boards were dipped in 1% aqueous solution for 3-10 minutes. The present results definitely support that BAM has a high potential to replace the currently used anti-sapstain formulations containing chlorinated phenols.
An example of media response to perceived environmental problems with CCA-treated wood
1990 - IRG/WP 3564
A recent study suggested that CCA-treated wood exposed to acidic precipitation could lose significant amounts of copper chromium and arsenic resulting in loss of efficacy and possible environmental contamination. The study received wide newspaper and radio coverage in Canada, thereby heightening public concern about CCA use. Subsequent studies in our laboratory confirmed that the high losses were caused by a citric acid buffer used to stabilize pH in the origional study. It is hoped that this "case study" will stimulate discussion and thoughts on how this type of situation should be addressed by scientists others involved with treated wood.
P A Cooper
Effect of vapour boron treatment on mechanical properties of wood based board materials
1992 - IRG/WP 92-3727
The mechanical properties of Medium density fibre board, Chipboard and Oriented strand board were investigated after treatment to two retention levels of boric acid applied as a vapour phase system. A range of mechanical properties were investigated. The vapour boron treatment does not have any significant effect on most of the mechanical properties of the boards. The exception is a reduction in impact strength especially at the higher retention level.
R Hashim, D J Dickinson, R J Murphy, J Dinwoodie
Preservative treatment of green timber by diffusion
1984 - IRG/WP 3291
The preservative treatment of green timber by diffusion is reviewed together with criteria which influence the economics of the process. New process options are described which should overcome some of the technical and economic disadvantages of double diffusion. These include the use of coagulating agents which increase the viscosity of the preservative solution and facilitate treatment by momentary immersion. It is anticipated that the main application for the diffusion treatment process will be for the treatment of refractory timbers for both ground contact and above ground exposure. The system is most suitable for low density and higher heartwood moisture content wood species - for example Sitka spruce, and is ideally suited for use in the tropics for treating both plantation grown softwoods and mixed tropical hardwoods.
Serial techniques for producing fire-retardant wood products
1997 - IRG/WP 97-30127
A series of techniques including fire-retarders denoted by WFR-1, WFR-2. WFR and their applications in producing fire-retardant wood (WFR wood), fire-retardant plywood (WFR plywood), fire-retardant particleboard (WFR particleboard) and fire-retardant MDF (WFR MDF) were investigated The fire retarders were low toxic, decay resistant and less leachable. The treated wood and WFR panels were of excellent fire resistance and good physic-mechanical properties. Besides formaldehyde released from WFR panels was very low.
Zhu Jia Qi, Liu Yan Ji, Gao Chao Ying
Distribution of fire retardant chemicals in kempas (Koompassia malaccensis)
1994 - IRG/WP 94-40037
Samples of Kempas (Koompassia malaccensis) heartwood were treated by vacuumpressure impregnation with solutions of monammonium phosphate, diammonium phosphate, ammonium sulphate or a borax-boric acid mixture. A commercial saltbased fire retardant formulation was also used. After slow air drying, the treated wood samples were sub-divided and zonal analysis carried out in order to determine the gradients of chemical retention form surface to core. Steep gradients of fire retardant chemicals were found irrespective of formulation. In a pyrolysis study, the amount of residue after pyrolysis at 550°C was proportional to the retention gradients of the fire retardant chemicals being greatest in the surface zones and least in the core of the samples.
A R A Malek, R J Murphy
Fungicidal effectiveness of amended alkylammonium compound
1987 - IRG/WP 3421
Amendment of didecyldimethylammonium chloride was attempted to improve its fungicidal effectiveness and properties of treating solutions. Addition of copper definitely increased effectiveness in controlling wood decay fungi, although metal corrosiveness and stability of treating solutions was unsatisfactory. Further amendment with stabilizer(s), anticorrosive agent(s) and sequestering agent(s) resulted in improving fungicidal effectiveness as well as properties of treating solutions. When a wood block was impregnated with an adequate mixture of didecyldimethylammonium chloride, copper sulphate, sequestering agent, stabilizer and anticorrosive agent (1:0.5:0.5:1:0.25), laboratory test (JIS A 93029) indicated that a lower retention level of didecyldimethylammonium chloride (1.1 kg/m³) gave a satisfactory protection to the block from decay fungi. On the other hand, didecyldimethylammonium chloride itself was effective enough at higher retentions of 2.2-4.3 kg/m³.
K Tsunoda, K Nishimoto
Fire retardant treated wood and plywood: A comparative study
Part III. Combustion properties of treated wood and plywood
2002 - IRG/WP 02-40236
The fire retardant treated and untreated plywood and alder wood samples were prepared with the aim to investigate the effects of the way of treatment on the combustion properties. Alder wood was used for the preparation of plywood. Boric acid and borax were used as fire retardant. The plywood samples were impregnated by using three different methods; first group samples were impregnated by soaking of individual veneer before manufacturing plywood. The second group samples were impregnated by adding boron compounds into the glue mixture and third plywood group samples were vacuum impregnated according to ASTM D 1413-88. In addition, the solid alder wood samples were impregnated with same fire retardant solutions for control purpose according to ASTM D 1413-88. The results showed that the most effective way of the treatment was the impregnation of plywood panels treated with boric acid and significantly reduced burning of plywood and solid wood samples.
S Çolak, A Temiz, Ü C Yildiz, G Çolakoglu