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By I M. Platten, C J. S Sangster, Y Xie

The Cononish gold-silver deposit is a steep, relatively narrow quartz-vein system, with a current total mineral resource of 154 000 oz Au and 589 000 oz Ag. The northeast-southwest trending system was emplaced into late Proterozoic metasediments, and postdates metamorphism and associated Caledonian Orogenic foliations. Assay and mineralogical data show that gold and silver is spatially associated with sulfides in quartz. The main sulfide is pyrite, but galena, chalcopyrite and sphalerite occur in small amounts. Gold occurs as electrum, with minor native gold, and silver occurs additionally as tellurides and native metal. The gold/electrum is fine-grained, generally less than 100 microns in size. The main ore shoots plunge 45¦ south-west, have a 40 m to 80 m intersection with the existing underground development and extend between 40 m and 260 m down plunge. Small-scale sulfide-bearing domains within the vein carry the highest gold grades. They collectively define the ore shoots, where one or two, and rarely three, of the domains are present at an individual site in the vein. Discontinuity of individual domains, variation in domain thickness and internal heterogeneity results in short scale variation in grade across the structure. Geological mapping along a 1.2 km exploration adit has provided critical æconditioningÆ data to support resource evaluation based on development and relatively wide spaced drilling. In addition, it has provided an indication of potential challenges that could be encountered during production.

Jan 1, 2009

By T. Wettainen

Malmberget town is located in northern Sweden, approximately 70 km north of the Arctic Circle. Parts of the town overlie more than 20 iron orebodies, consisting mainly of magnetite with smaller quantities of haematite. The mine is operated by the mining company LKAB. Mining started in the 17th century, but not until the railway to the coastal city of Luleå was completed in 1888 did large-scale production commence. Around 1920, mining proceeded underground and today sublevel caving is the only mining method used. Sublevel caving causes subsidence of the ground surface, and buildings and residential areas have been relocated due to the mining activities for more than 50 years. The number of seismic events accompanied by strong ground vibrations is now increasing. In 2008 the mine received a permit from the Environmental Court of Sweden to increase production to 20 Mt of crude ore per year. A prerequisite for the permit was that the mine conducts a number of investigations regarding the environmental impact on the residents of Malmberget. One of these investigations concerned how seismicity will change as production increases and what measures could be taken to reduce inconvenience to the town residents. Today the mine possesses an extensive seismic monitoring system with more than 180 underground and surface geophones. For this study, eleven seismically active volumes in Malmberget mine were identified, and for each of them, a yearly future maximum magnitude interval was estimated based on the current production plan. Relationships between historical seismic events and measured ground vibrations in the town of Malmberget were established, and future ground vibrations caused by expected seismic events were estimated using a probabilistic approach. The outcome was the number of intervals of expected ground vibration per year and per monitoring point. Possible measures to reduce inconvenience for the town residents include blast restrictions, sequencing, and possibly preconditioning. The ultimate long-term solution is an almost complete relocation of Malmberget town. This process has recently been formalized and LKAB is taking an active part in realizing this goal.

Jan 1, 2014

By Boorder De, B. S. Panov, A. B. Westerhof, V. A. Korcemagin

Paper presented at the conference on Economic geology in Europe and beyond II, models for <mineral deposits> in sedimentary <basins>, held in Keyworth, UK, 13-14 April 1994. The Hg and Sb deposits of the Mediterranean and Circum-Pacific Belts are often found at elevated structural levels, suggesting that their preferential occurrence in young orogenic belts is not a fundamental metallogenic feature but merely reflects their chances of surviving post-orogenic peneplanation. In western Europe their emplacement appears often to be related to late orogenic extensional events accompanied by a notable increase in heat flow. Although Nikitovka and Almaden have quite different settings, both appear to be related to deep-reaching shears. Together with brittle fault zones at higher levels, these provided pathways for fluid phases that originated at least partially within the mantle. The Nikitovka deposits are located in the Donets segment of the 2 000 km Pripyat-Dniepr-Donets palaeorift in the East European Platform. Initiated in the mid-Devonian with a possible Precambrian precursor, its listric boundary faults displace the Moho from a depth of about 50 km north and south of the rift to 35 km along the axes of the Pripyat and Dniepr segments. The steep central anticline of the Donets segment, within which the main Hg-Sb district is located, is interpreted to be associated with a reactivated fault reaching into the upper mantle. The Almaden syncline, formed during the Variscan Orogeny, may be an older pull-apart basin or half-graben associated with the collapse of the Cadomian Orogenic Belt. It is situated on a major ENE-WSW-striking shear zone which may represent a Late Cadomian transfer zone reaching into the mantle

Apr 1, 1995

By Martin Herrenknecht

Tunnel boring machine (TBM) development continues to take on not only larger diameters, but also more difficult ground conditions. Ground conditions consisting of unstable faces with water pressures up to 15 bar have required innovative design approaches. A systems approach has been required to produce tunneling machines that can safely excavate the tunnel in an efficient, cost-effective manner that stresses production and labor saving approaches. This article reviews the current design developments and present recent projects where these most recent principles have been applied. The world?s growing population and rapidly proceeding urbanization are boosting an enormous demand for new and high-capacity infrastructures to secure the mobility of goods and people. Densely populated areas face the challenge of providing efficient traffic infrastructure such as a modern public transport system. At the same time, the maintenance and modernization of supply and disposal structures for water, sewage, energy and communication are essential. Last but not least, are supra-regional transportation routes such as long distance water diversion schemes. All of these projects are as demanding and are characterized by a tight time schedule. In this context, the demand for efficient tunnels for traffic and utility lines is increasing, as new infrastructures often leads underground because of limited space above ground. Also, tunnels are the obvious choice to cross natural barriers like mountain ranges. To handle the complex and variable geological conditions and other constraints, such as low overburden, high water pressure or long tunnel drives while facing increasing demand of a quick completion of a project, mechanized tunneling sets standards regarding safety, profitability and environmental protection in traffic tunneling projects as well as in the trenchless construction of utility tunnels. Different machine types and working principles have been developed to master various geological and hydrogeological requirements. Continuous activity in research and development leads to constant improvement of the mechanized tunneling process.

Jan 1, 2008

By Javaid M. Alvi

This paper is an attempt to outline the emergence of Augered Cast-ln-Place piles as one of the more economical types of foundation for supporting high-rise buildings and heavily loaded structures recently constructed in the flood plains in and around the Greater Pittsburgh area. To understand the process of selecting foundation types, it is important to understand the general geology of the area and past construction activities that have taken place in the flood plains, especially along the riverbanks, during the last century. The first part of this paper presents a brief description of the general geology of the area; the second part of the paper concentrates on the historical evolution of the use of deep foundations and selected case histories; and the last part presents the results of load tests on large diameter Augered Tremie Concrete (ATC) Piles placed in sandy alluvium which suggests a much larger load-carrying capacity of these piles and also provides an insight into their future application. 2.0 GENERAL GEOLOGY 2.1 Soil Overburden Most of the high rise buildings in the Central Business District as well as along the North Shore and South Side of Pittsburgh are situated in the flood plain at the confluence of the Allegheny River and the Monongahela River where their combined flow forms the Ohio River. The flood plain consists of unconsolidated deposits of Quaternary age that overlie the bedrock of Pennsylvanian age. These deposits are called alluvium or valley fill, and include moderately to poorly sorted clay, silt, sand, gravel and some boulders. Their thickness varies from zero at the edges of the valley to about 80 feet towards the rivers (Figure 1).

Jan 1, 2001

By C. F. McCarroll

The effectiveness of an industry?s safety activities can be gaged best by the accident records of that industry. In an effort to gage conditions in the petroleum industry, and with the objective of helping to reduce the number of accidents in it, the Bureau of Mines from time to time has tabulated, analyzed, and published pertinent statistical information3/. These reports have dealt with distribution, causes, and costs and related phases of accidents for various and collective divisions of the petroleum industry in several sections of the country. This type of study aids the personnel of the Bureau in planning the course of its activities in accident-prevention work and gives useful data to persons engaged or interested in the promotion of safety in the petroleum industry, which will aid them in their efforts to reduce the number and severity of accidents. A majority of petroleum operators and ?service" contractors have acknowledged their responsibility to provide their employees with safe working conditions and to their stockholders for greater economic value of invested capital by establishing safety divisions within their respective organizations. Such divisions have a primary duty, namely, to see that properly designed and guarded machinery and working equipment are furnished the employees and that they are trained in the safest practical methods of performing their work. Some companies and individual operators, however, have shown little or

Jan 1, 1939

By S. A. H Tyrrell, R. Rotzinger

"Taseko Mines Limited recommenced operation of the Gibraltar copper-molybdenum mine in 2004 and embarked on series of development projects to modernize the mine and increase throughput capacity. The Gibraltar Development Plan 3 (GDP3) project included a second stand-alone copper-molybdenum concentrator, a stand-alone molybdenum separation plant and associated services. Ausenco was contracted to commence the detailed design in 2Q2011, commissioning commenced in 4Q2012 and first ore was processed in 1Q2013. This paper discusses the design, implementation and commissioning of the GDP3 Concentrator.INTRODUCTION The Gibraltar Mine (Gibraltar) property is located in the Cariboo Region of south central British Columbia, approximately 360 kilometers northeast of Vancouver. The site is accessed via an 18 kilometer paved road from the town of McLeese Lake, which is located on the province’s main north-south highway between the cities of Williams Lake and Quesnel. Gibraltar was originally developed by Placer Development and commenced production in 1972. Gibraltar was acquired, while on care and maintenance, by Taseko Mines Limited (Taseko) in 1999 during a period of unusually low metal prices. Taseko recommenced operations at Gibraltar in 2004, and embarked on series of development projects to modernize the mine and increase throughput capacity. The 1972 Gibraltar process flowsheet incorporated two-stage crushing followed by rod and ball milling and flotation. In 2008 Gibraltar completed their first development stage that included the installation of a SAG mill, converting the existing rod mills to ball mills and adding additional flotation capacity. Gibraltar continued development with the installation of an in-pit primary crusher, expansion of the bulk regrind circuit, expansion of the cleaner flotation circuit, replacement of the tailings pumping system and replacement of the concentrate filters and dryer."

Jan 1, 2014

By H.A. Bedworth

AlloTs of copper and silicon have been known for one hundred years or more but the commercial development of this type of alloy has taken place during the past few years. In 1905, Sperry l proposed the use of copper-silicon alloys for springs and other purposes for which copper-tin bronzes were used. Some attention was given to this proposal at the time but no one succeeded in producing a practical alloy containing more than a fraction of a per cent. of silicon. The equilibrium relations of the copper-silicon system were studied first by Rudolfi2 and later by Sanfourche 3 and Corson. 4 The constitution of the system has also been recently investigated by Matuyama, 5 and in the laboratories of the American Brass Co. by Smith. 6 Some of the physical properties of the copper-silicon alloys have been investigated by Norbury7 and by Geiss and Van Liempt.8 Summarizing the results of various investigators of the constitution of copper-silicon alloys, the solubility reaches its maximium value, 6.7 per cent. silicon, between 721" and &apos;782" C. At 852" (1. the solubility is 5.25 per cent., while at 400" C. it is only 4.1 per cent. silicon. The copper-silicon alloy begins to get so hard at about 3 per cent, silicon that it is difficult to manage. It was found by Jacobs that the addition of manganese to this alloy considerably improved the working

Jan 1, 1929

Characterisation of Computer Printed Circuit Boards for Hazardous Properties and Beneficiation Studies

Sep 13, 2010

By P. Mark. Hawley

Development of Barrick Gold?s Pierina Gold Mine in north-central Peru requires construction of a waste dump for disposal of non-ore grade materials stripped from the open pit to expose the ore. The waste dump site is located near the open pit in a U-shaped valley that is underlain by thin colluvial and morainal soils with locally thick peats and glaciolacustrine deposits. Bedrock underlying the site consists of variably weathered volcanics. The site is subject to moderately high seasonal rainfall and significant seismicity. The geotechnical quality of the waste rock is highly variable, ranging from low quality, degradable, soil-like materials containing appreciable quantities of silt and clay, to high quality, hard, durable, blocky waste rock. A hybrid dump design concept was developed that requires in-pit segregation of high and low quality waste, and selective placement of materials in the dump to maximize stability and enhance internal and subsurface drainage. The design includes a rock drain beneath the dump along the axis of the valley and a series of connected finger drains. Extensive peripheral diversions and stormwater control measures to inhibit infiltration of precipitation are also included. This paper discusses the unique challenges presented by the site and waste materials, the design methodology and stability analyses, and planned monitoring systems.

May 1, 2002

By M. Dondelinger

This paper presents a comprehensive review of steel sheet piling including internationally manufactured hot rolled sections, their history, applications, installation and driving techniques. The discussion will cover both temporary and permanent installations; temporary piling used in construction of cofferdams with various bracing systems, deep foundation installations for buildings, bridges and tunnels, etc., and permanent piling used for highway, railroad and bridge construction as well as for riverbanks, piers, wharfs and docks, normally required for port facilities. In addition, cofferdams, as self-supporting gravity structures where interlock strength is of prime importance, will be discussed. The design and application of light, intermediate and heavy sections will be presented including heavy combined walls and information on Z-shaped, U-shaped and HZ sections and their corresponding interlocks. Emphasis is placed on new developments for design applications for deep foundations and waterfront structures within the "state of the art".

Jan 1, 2010

At Great Boulder Gold Mines Ltd. a number of attempts were made to remove water soluble copper and iron salts from calcined pyritic concentrates but variou~ problems arose and the methods were abandoned.A method of rapid washing has been developed and although some problems still exist a workable process was established which resulted in substantial savings of reagents used for the cyanidation of calcine.INTRODUCTIONIn the Great Boulder flowsheet crude ore is ground in cyanide solution, then thickened, agitated and subjected to two stage filtering. Secondary filter discharge is pulped with flotation circuit water, gassed with sulphur dioxide to precipitate soluble gold and activate pyrite, and after the addition of copper sulphate and xanthate, the pyrite and tellurides are recovered by flotation. Flotation tailings are thickened and pumped to the disposal area and concentrates are calcined in Edwards roasters. Calcine is washed to remove water soluble copper and iron salts and the washings pumped to the flotation section where the copper is used as an activator. The washed calcine is cyanided and returned to the crude ore circuit via the thickeners. Solution for precipitation in the Merrill Crowe is drawn from the crude ore thickeners.Prior to the introduction of calcine washing the calcine contained 7 lb/ton copper of which approximately 60 per cent was water soluble. It also contained approximately 90 lb/tol&apos;l of water soluble iron salts. Both the copper and...

Jan 1, 1964

By J. R. Parga

In mineral processing, poor froth-flotation performance translates into both an enormous loss of revenue and an unnecessary waste of the ore reserve. In this context, Bacís Mining Company developed a versatile new, high-performance flotation-cell design that can be incorporated into various flotation circuits. The main feature of this circular cell is that it is comprised of two separate sections, namely, a flotation cell that uses wash water to minimize the entrainment of fine gangue particles into the froth product and an external bubble generator that produces small bubbles of relatively uniform size at a specified aeration-rate. The air/water mixture is blended with the pulp by gentle agitation, so as to enhance particle-bubble aggregate-stability. Comparative metallurgical performance with conventional flotation cells show that the power requirements and operating costs for precious metal flotation are three times lower, while the concentrate grade is 7% higher and the recoveries of precious metals are 5% higher.

Jan 1, 2009

By Kevin Connor

There was little change during 1988 in the production of minerals in Burundi. The Government of Burundi, which banned all commercial mining operations in the country in 1979, lifted the ban on mining of alluvial gold deposits and started a program of small-scale artisan gold mining in October. Along with the legal mining of gold, licensed gold trading counters were established. Other mineral commodities produced were kaolin clay, lime, and peat. In compliance with the Government ban, the only mineral wealth exploited for commercial sale and export was alluvial gold. Through financial assistance from the International Bank for Reconstruction and Development (World Bank) and the United Nations Development Program (UNDP), a study to inventory the country&apos;s mineral resources continued throughout the year. As part of this study, during the year, a West German company undertook a drilling program to further outline the nickel reserves of the Musongati area in central Burundi. Results of the work as of yearend were disappointing, with only 12 million tons of ore identified with better than 2% nickel content proven. Investigations also continued during the year regarding the centrally located deposits of vanadium-bearing titaniferous magnetite. A Norwegian company contracted to prepare a prefeasibility study for developing the deposit. The British Sulphur Corp. Ltd. was nearing completion of its $1.2 million2 study of the phosphatic limestone deposit at Matongo-Bandaga at yearend. Ore reserves of about 17 million tons grading 11% phosphorus pentoxide (P2O3) had been identified. The phosphate zone overlies a carbonatite rock, which could provide the basis for a cement industry. Additional drilling was planned for 1984. Exploration for gold was underway in 19S3 in northern Burundi through UNDP funding. Several primary deposits of shallow semimassive sulfides with gold values ranging from traces to 11 grams per ton had been discovered. With assistance from the Federal Republic of Germany, bastnasite reserves of 5,400 tons, with associated high europium oxide and cerium content, were verified, and the prospects for finding

Jan 1, 1985

By D. Lindeman, R. M. Nendick

"From a technologist's point of view, there have been few fundamental 'breakthroughs' in the process of gold extraction since the turn of the century. However, the industry has made a great deal of progress in its response to the problems that have arisen: a changing demand for products, lower grade and more refractory ores, inflated labour and materials cost and the increasing control of governmental legislation. The trend in North America and South Africa to alleviate these problems has been to adopt a common policy to process larger tonnages of lowgrade ore through more efficient milling circuits. Here, however, is where the similarity ends.The purpose of this paper is to emphasise the different principles of practice employed by extraction plants in North America and South Africa to achieve the same common goal, namely gold bullion.2.0 INTRODUCTIONTwo very important aspects of extraction metallurgy for which the metallurgical engineer is responsible are plant design and plant commissioning.In North America and South Africa the importance of these aspects is due to the fact that both are related to the financial success of the project of which they form part. Good design is imperative if the capital invested in both the plant and the whole mining undertaking is to reap maximum profit. Furthermore, good design leads to a carefully planned and well executed start-up procedure resulting in bringing the plant into production on time, at designed efficiency and within budget.Due to the competent nature of the quartz pebble conglomerate and quartzite ore on the South African Witwatersrand, the characteristics of the ore type are not much different from one mine to the other. Thus a significant operating knowledge and experience has been built up over the years and there is considerably less risk in selecting a gold extraction process route."

Jan 1, 1992

By Mohammed Y. Fattah, Wissam H. S. Al-Sudani

"During installation of pile, a soil column is formed inside the pile. For small depths, the height of the soil column typically equals to the penetration depth (full coring state). As the penetration depth increases, the developed internal shear stresses become larger and reduce the amount of soil to penetrate. At the same time, the soil in pile at the bottom is compacted. This will continue until at a given moment, the soil column is a soil plug, and does not stop moving relative to the pile. This is because the shear stresses developed in the interior of the pile are greater than the load-bearing capacity of the ground.This paper presents the results obtained from 40 model pile tests carried out to assess the effect of soil plug on the model pile capacity. The piles are embedded in sand of different densities with different lengths of piles and types of pile-ends. The model tests are divided into two parts according to the type of end of the pipe pile used in the model pile test. The first part consists of 32 model open-ended piles with different lengths of soil plug inside the pile. The second part consists of 8 model closed-ended piles.It was concluded that open-ended pipe piles behave as a closed-ended if the soil plug formed inside piles in state partial plug or full plug. Length of soil plug depends on the type of installation and relative density. The pile load carrying capacity in dense sand is several times greater than those in medium sands especially in cases of closed ended piles or open-ended since the pipe pile can produce external and internal skin friction in addition to end bearing resistance that makes the total pile capacity close to that of closed-ended pile. Whether open-ended piles are driven or pressed in the fully coring - fully unplugged mode or in the partially plugged mode, the plug does contribute to static pile base capacity."

Jan 1, 2014

The notes from which this paper has been prepared were set down at the time of the author&apos;s departure from Australia in 1935. Mr. Frank Forman, Government Geologist of Western Australia, who has very kindly read the paper in manuscript, affirms that the views here set forth are now accepted by most geologists. Thus, Forman&apos;s recent presidential address before the Royal Society of Western Australia (1937) mentions sediments in the Kalgoorlie Series &quot;including banded jaspers and jaspilites.&quot;While it may, therefore, be superfluous to belabour the question further at this time, Mr. Forman has encouraged the author to publish this paper as a summary or both past and present views.To those specially interested in the subject of the paper, a study of pertinent Plates attached to Western Australian Geological Survey Bulletin No. 71, 1917, is suggested.The type of rock which is variously called &quot;jasper bar,&quot; jaspilite, or &quot;ferruginous quartzite&quot; is familiar to all mining men who have worked in the West Australian goldfields.In its typical form it is a &quot;striped&quot; rock consisting of alternate layers of white or pinkish silica with red to brown bands of iron-bearing silica.In the course of geological work in many parts of Western Australia I studied exposures of jasper bar and was repeatedly impressed with the similarity of much of the material to the sedimentary &quot;banded iron formation&quot; of Canada. It was, therefore, a surprise to learn that the jasper bars were not generally regarded in Australia as sedimentary horizons. It is true that Honman offered convincing evidence of the sedimentary origin of the jaspers...

Jan 1, 1939

Remote sensing, in general, is the recording of light and heat from a planet&apos;s surface within a certain range of the electromagnetic spectrum. For the Earth, systems capable of this recording are the MultiSpectral Scanner (MSS) and SLAR. The former is the recording system used in satellite and will be discussed in the next section. SLAR stands for Side Looking Airborne Radar. This device sends invisible radar waves which illuminate the Earth&apos;s surface. The reflected waves are subsequently recorded as images. The system can operate through darkness and dense cloud cover, and is particularly suited for the study of geological structures at both large and small scale (Wayland 1976). Remote sensing techniques are now widely being made use of in mineral exploration, especially for those last remote &apos;sanctuaries&apos; where geological data are meagre or non-existent. For places like Borneo, West Irian, the Amazon Basin etc. remote sensing, in the form of both satellite imagery and SLAR, is of considerable help, in fact more often than not the only help, to delineate geological provinces, geotectonic domains and meaningful lineaments. In the case of New Zealand, well made geological maps at scale 1:250&nbsp;000 by the Geological Survey are available to the public and these provide useful preliminary grounds for the selection of target areas. However, even in this case LANDSAT imagery can be of aid as will be shown later.

Jan 1, 1977

By Paul Morrison

The paper describes the design process, trial testing and contract pile installation of 772 pre­cast concrete piles at a site in Surrey, South East England. Recommendations on how to improve the design, construction trials and main contract piling phases of the project are made. The building layout is shown in Figure 1 and is comprised of a central circulation area with five office wings radiating out from its southern side (only three of these wings were constructed in Phase 1 of the project). Approximately 60% of the circulation area and one office wing were built with a single level basement. The basement was constructed "bottom-up" in open cut with the void between the basement walls and the cut slope being back-filled with compacted site won soil above a perimeter drainage system at basement slab level. The building has up to 3 stories above basement level and is a reinforced concrete structure. The client for the project is Pfizer Ltd. Pfizer Ltd was represented on site by Laing Project Management (Laing). The consulting engineer was Ove Arup and Partners (Arup) while the piling contractor was Roger Bullivant Ltd (RBL).

Jan 1, 2000

By A. G. Mayton

Vehicle vibration exposure has been linked to chronic back pain and low back symptoms among agricultural tractor drivers. The objectives of this study by the National Institute for Occupational Safety and Health (NIOSH) were to assess driver whole body vibration (WBV) exposures and recommend interventions to reduce the risk of back related injuries, particularly relative to vehicle jarring/jolting (the transient mechanical shock components of WBV). The methodology included collecting, from two independent samples, ?eld data and health and work history data of farm equipment operators. Data were collected during mowing, raking, baling, chiseling, tilling, and road travel for different model tractors. Spraying using a sprayer and shrub removal with a skid steer loader were also included. Based on ISO 2631 (1985), the American Conference of Governmental Industrial Hygienists, threshold limit values, presents 0.5 m/s2 as the action level recommended by the Commission of European Communities for overall weighted total RMS acceleration (vector sum for axes x, y, and z) [ACGIH, 2006. Threshold limit values and biological exposure indices. Cincinnati, OH]. WBV measured at the operator/seat interface exceeded this action level. The roughest rides and highest vector sum accelerations occurred with small utility tractor mowers (3.3 and 2.8 m/s2) and a skid steer loader (1.7 m/s2). Major ?ndings from health and work history data showed 96% of participants reported having to bend or twist their necks, although 24% reported neck symptoms. Sixty four percent of participating operators reported experiencing back symptoms (e.g., pain, aching, stiffness, etc.). Recommendations included: specifying a seat that ??better?? isolates operators from jars/jolts with new tractor purchases; maintaining the seat/seat suspension and replacing worn or damaged cushions with NIOSH tested viscoelastic foam padding; using larger diameter tires with radial ply instead of bias ply construction, particularly on small utility tractor mowers, to aid in attenuating ride ??roughness??; using a swivel seat to reduce the stress on the neck from bending or twisting; and improving efforts to educate owner/operators of the adverse effects of WBV exposures. Since the data presented in this paper were collected from two independent samples, the authors were unable to draw any correlations or etiological inferences from the study. However, results were compared and contrasted with other studies which included similar vibration measurements in agriculture.

Jan 1, 2008