Your search resulted in 51 documents. Displaying 25 entries per page.
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, clea...
Mick Hedley, Dave Page, Jackie van der Waals
Fungal and bacterial attack of CCA-treated Pinus radiata timbers from a water-cooling tower
1991 - IRG/WP 1488
Transmission electron microscopy of decaying CCA-treated Pinus radiata timbers from an industrial water cooling tower showed presence of a thick biofilm covering some areas of the wood. The biofilm contained various morphologically distinct forms of microorganisms embedded in a slime. The study provided evidence of the activity of soft rot fungi and tunnelling and erosion bacteria in wood cells. T...
A P Singh, M E Hedley, D R Page, C S Han, K Atisongkroh
Types of decay observed in CCA-treated pine posts in horticultural situations in New Zealand
1984 - IRG/WP 1226
The few reported failures of 11-12-year-old horticultural posts in New Zealand in 1982 were caused by brown-rot. A subsequent survey of CCA-treated posts in all the major horticultural areas has revealed decay of many posts. A microscopic examination of these posts has shown decay by brown-rot, white-rot, soft-rot and bacteria. Several types of bacterial decay have been observed....
J A Drysdale, M E Hedley
Performance of Tebbacop in laboratory, fungus cellar and field tests
2000 - IRG/WP 00-30222
A novel organo-copper wood preservative ("Tebbacop") has been exposed to 12 years fungus cellar testing and 6 years above ground field testing. In the fungus cellar, Tebbacop at a retention of 0.053% Cu m/m oven dry wood out-performed CCA at a retention of 0.55% m/m oven dry wood. In above ground tests, L-joints treated to a Tebbacop retention of 0.012% Cu are performing as well as joints treated ...
M E Hedley, D R Page, B E Patterson
Protocol for evaluation and approving new wood preservative
1985 - IRG/WP 2159
M E Hedley, J A Butcher
Multiple-Phase Pressure (MPP) Process: One-stage CCA treatment and accelerated fixation process. 5. Treatment of Sitka spruce and Scots pine
1999 - IRG/WP 99-40136
The suitability of the MPP Process for CCA treatment and accelerated fixation of species other than Radiata pine was assessed by pilot plant trials on UK-grown Sitka spruce (Picea sitchensis) and Scots pine (Pinus sylvestris). Pressure and vacuum kickbacks of spruce (14 l/m3) and Scots' pine (122 l/m3) were both substantially lower than that generated during treatment of radiata pine (369...
M E Hedley, K Nasheri, G Durbin
Comparison of decay rates of preservative-treated stakes in field and fungus cellar tests
1980 - IRG/WP 2135
With the exception of acid-copper-chromate, zinc-chrome-arsenate, and sodium pentachlorophenoxide, the relative performance of preservatives in the fungus cellar was similar to that in the field....
M E Hedley
Preservative requirements for exterior particleboard as predicted from accelerated laboratory evaluations
1976 - IRG/WP 265
Arguments for and against preservative treatment of exterior particleboard were considered; it was concluded that preservative treatment is desirable. Laboratory decay tests were conducted to determine levels of sodium pentachlorophenoxide required to protect exterior particleboard from decay fungi. The decay resistance of treated board was compared with that of timber (both naturally durable and ...
M E Hedley
Long term performance of CCA preservatives in ground contact
2000 - IRG/WP 00-30223
Copper-chrome-arsenate (CCA) preservatives have been use extensively in New Zealand since the mid-1950s for a wide range of ground contact uses, radiata pine being the main species treated. They have been the subject of a comprehensive field testing programme in up to five sites in New Zealand, the earliest tests being established in 1955. Main factors affecting performance have been formulation t...
M E Hedley, D R Page, B E Patterson
Changes to New Zealand Timber Treatment Specifications
2004 - IRG/WP 04-20288
Changes have been made to the New Zealand timber treatment specifications in response to frequent incidences of decay in framing timber and doubts about the long-term performance of tributyltin formulations when used in exposed situations.
Changes have been made to Hazard Class H1 to allow a level of treatment to provide short to medium decay resistance to framing which would protect it, should l...
M E Hedley
Development of an Australasian protocol for assessment of wood preservatives
1994 - IRG/WP 94-20043
The Australasian Wood Preservation Committee (AWPC) is currently developing a suite of assessment procedures (protocols) for the biocidal efficacy of wood preservatives for approval in Australasia (Australia, New Zealand, Papua New Guinea, Fiji). Protocols are being prepared for the six hazard levels recognised in the relevant standards of member countries and represent the minimum procedures requ...
W D Gardner, H Greaves, M E Hedley, K J McCarthy, J Norton
Comparison of decay rates of preservative-treated stakes in field and fungus cellar tests. Results after 40 months fungal cellar exposure
1983 - IRG/WP 2200
Decay rates of preservative-treated Pinus radiata stakes during 40 months exposure in the FRI fungus cellar were compared with those of similarly treated material in a field test. Decay rates in the fungus cellar were from 4 to 100 times higher than in the field, although for the majority of preservatives the rate was between 7 and 12 times higher. The lag phase before onset of decay, noticeable w...
M E Hedley
Ultrastructure of degraded, CCA-treated Pinus radiata wood from a marine pile
1990 - IRG/WP 1461
During an inspection of marine piles, 12 years after installation, severe degradation was noted on one of them in the vicinity of a corroded eye-bolt. The wood was dark brown in colour and tended to crumble easily. Wood fragments were examined by light microscopy and scanning and transmission electron microscopy and were also analysed for carbohydrates and lignin. Light microscopy showed numerous ...
A P Singh, M E Hedley
Issues Facing Wood Preservation in New Zealand Today
2003 - IRG/WP 03-30326
In New Zealand, the three major issues facing the wood preservation industry today are:
Extension of use of LOSP preservatives, chiefly tributyltin naphthenate, for treatment of products in Hazard Class H3 exposed to the weather for which LOSP have not been traditionally used. Concerns have been expressed about the long-term durability of such products.
Restrictions on the use of CCA preservativ...
M E Hedley
Effect of treatment process on performance of copper-chrome-arsenate. Part 2: Field stake tests
1995 - IRG/WP 95-40046
Pinus radiata sapwood stakes 20 x 20 x 400 mm³ were treated with CCA Type C using a range of concentrations and three treatment processes; Bethell, Lowry and Rueping. Preservative retention was determined by chemical analysis of treated material. Following fixation stakes were installed in a randomised plot in the Whaka graveyard located on the FRI campus. Stakes were inspected at yearly interval...
M E Hedley, J Anderson, J B Foster, B E Patterson
Comparative moisture uptake of Douglas fir and radiata pine structural lumber when exposed to rain wetting as an indicator of relative decay resistance
2004 - IRG/WP 04-20285
Trials were undertaken to determine the relative resistance of radiata pine and Douglas-fir to wetting when exposed to the weather.
Douglas-fir samples were obtained from one Central North Island and three South Island sources and had a heartwood/sapwood mix typical for each resource. Radiata pine sapwood and heartwood samples were obtained from a Central North Island source. Material was exposed...
M E Hedley, G Durbin, L Wichmann-Hansen, L Knowles
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...
M E Hedley, R W Naish
Above-ground field tests undertaken in New Zealand
1995 - IRG/WP 95-20063
In addition to "standard" L-joints, above-ground test material exposed at the NZ FRI test site includes treated and untreated decking units, Y-joints, fence battens and weatherboards either with or without additional protection from surface coatings. The latter tests bridge the gap between "model" test assemblies, such as L-joints, and services tests. Most tests are of preservative-treated radiata...
M E Hedley, D R Page, J B Foster, B E Patterson
An evaluation of chemical treatments for the protection of radiata pine logs from fungal degrade
1986 - IRG/WP 3377
Busan 30, Busan 1009, Mitrol PQ375. and sodium pentachlorophenoxide (NaPCP) plus have been evaluated as antisapstain treatments for the long-term protection of debarked radiata pine logs. After 3 months' winter-spring storage, treated debarked logs had less surface and internal sapstain than 'control' logs. After 6 months' storage all logs had internal sapstain ...
J A Drysdale, M E Hedley, J A Butcher
Field tests of preservative-treated radiata pine in Japan
1995 - IRG/WP 95-30083
Test stakes of radiata pine treated with various alkyl ammonium compound (AAC) formulations and with copper-chrome-arsenate (CCA) as reference preservative were installed in 3 test sites in Japan in 1981-82. When inspected in 1995, CCA-treated stakes showed less decay at all three sites than stakes treated with other formulations. Ammoniacal copper quaternary (ACQ)- treatment was only slightly les...
M E Hedley, K Tsunoda, K Suzuki
A new technique for testing decay resistance of framing lumber
2002 - IRG/WP 02-20247
Model house frame units (two studs, top and bottom plates and a central “dwang”) were constructed using short (500-600 mm) lengths of framing timber. Constructed frames were impregnated with water using a mild pressure schedule to raise the initial moisture content to 35-40 % mc. The back face of each unit was then covered with black polyethylene. Two locations at the stud/dwang and stud/botto...
M E Hedley, D Page, B E Patterson
The multi-phase pressure (MPP) process. One stage CCA treatment and accelerated fixation process
- Concepts proved by repetitive pilot plant treatments
1997 - IRG/WP 97-40079
Twenty-four charges of radiate pine roundwood or sawn timber were treated using the MPP Process and hot CCA solution. Treated timber met the CCA retention and penetration requirements of the NZ Timber Preservation Council for Hazard Classes H3 to H5. The objectives of the trials were: (1) To "stress" CCA solution by repetitive heating, treating and cooling to determine its stability in the process...
A J Pendlebury, J A Drysdale, K Nasheri, H Pearson, M E Hedley
Relative performance of copper/chrome/boron (CCB) and copper/chrome/arsenate (CCA) in ground contact
1992 - IRG/WP 92-3694
The performance of four retentions each of an oxide CCA formulation and a salt formulation of CCB in radiata pine and European beech was compared after 18 years' field exposure. In radiata pine CCA oxide was more effective (4 failures out of 40) than CCB (9 failures out of 40). However, in European beech CCB was substantially more effective (22 failures) than CCA oxide (all failed). Analy...
M E Hedley
Observations on the performance of copper-based wood preservatives in fungal cellar (soil-bed) tests
1994 - IRG/WP 94-20047
Fungal cellar (soil-bed) tests are considered to be an important tool for the evaluation of the performance of ground contact wood preservatives. Facilities of this type have been established world wide although caution has been exercised in their introduction into standard testing methods for the approval of wood preservatives. This is the result of concerns over the variability in the biological...
G R Williams, D Rudolph, M E Hedley, J A Drysdale, R F Fox
The effect of extent and location of decay on strength loss in constructional timber
1994 - IRG/WP 94-30039
Radiata pine heartwood billets, 50 x 100 x 1000 mm³ were end-sealed and treated with copper-chrome-arsenate preservative (NZ Type I) to a range of retentions and penetration patterns. Cross-sections, 10 mm thick, were cut from the centre of each billet and used for determination of preservative distribution, for preservative analysis and for decay tests. The decay test consisted of laying samples...
M E Hedley, H Bier