Dust Monitoring and Control Downloadable Mining Publications

Water spray characteristics, including droplet size and velocity, airborne dust capture potential, and induced airflow quantity for various spray nozzle designs were evaluated to provide basic information for improving spray applications. Test results indicate that there are trade offs between airflow inducement and dust capture efficiency. This information can be utilized to improve the performance of water sprays for reducing airborne dust levels. (PDF, 1837 KB, 2007-07)

This paper describes laboratory experiments in a wind tunnel with a roll crusher to identify relationships among crushing parameters, product size, coal rank properties and airborne dust generation. (PDF, 1143 KB, 2001-06)

This report examines the effect of oversize particles, cyclone inversion, and cleaning procedures on the Personal Dust Monitor (PDM).  (PDF, 276 KB, 2008)

The National Institute for Occupational Safety and Health (NIOSH) Office of Mine Safety and Health Research (OMSHR) has conducted a series of large-scale explosion experiments at the Lake Lynn Experimental Mine (LLEM) to investigate the inerting effect of limestone rock dust. Numerous experiments were conducted using a pulverized Pittsburgh coal dust (PPC) mixed with limestone rock dust to achieve total incombustible contents varying from 67 to 82%. These dust mixtures were entrained and were subsequently ignited, if insufficient incombustible was present, by the ignition of a methane-air zone located at the closed end of the entry. Electronic flame sensors were positioned at regular intervals along the length of the entry to measure the flame travel. Post-explosion dust residue samples were taken along the entry after each explosion and analyzed to infer flame travel by measuring the thermal decomposition of limestone rock dust. Alcohol coking indices of the post-explosion residues were also measured. The alcohol coking test method is a forensic tool currently used by the Mine Safety and Health Administration (MSHA) in accident investigations.The determination of the extent of flame travel by these different measurement methods are discussed and compared. The rock dust solubility test described in this paper could assist accident investigators in more accurately establishing the flame limits of a dust explosion.  (PDF, 1578 KB, 2011)

Dust control modifications were implemented on small, truck-mounted rock drills at surface coal mines. The control techniques showed noticeable improvement in measured dust concentrations around the drills. (PDF, 1400 KB, 1995)

A system to reduce occupational dust exposure during bag loading and stacking operations in the metal mining industry was developed. The system, known as the Bag and Belt Cleaner Device (B&BCD), was developed by NIOSH, and designed to clean the surfaces of 50 and 100 pound (lb) bags and conveyor belts while the bags were transported to stacking locations. (PDF, 339 KB, 1997-03)

The National Institute for Occupational Safety and Health (NIOSH) conducted a series of benchmark surveys at longwall operations across the country to identify current operating practices and the types of controls being used. Gravimetric and instantaneous dust sampling was completed to quantify the dust levels generated by major sources on the longwall section and to identify different control technologies in use today. Substantial reductions in dust levels were realized at sampling locations on the face when compared with longwall surveys conducted in the 1990s. Results from the underground dust surveys and current longwall dust control technology and operating practices will be discussed.  (PDF, 1003 KB, 2011)

In light of the ongoing severity of these lung diseases in coal mining, this handbook was developed to identify available engineering controls that can help the industry reduce worker exposure to respirable coal and silica dust. The intent was to identify the best practices that are available to control respirable dust levels in underground and surface coal mining operations. (PDF, 4468 KB, 2010-01)

This handbook was developed to identify available engineering controls that can assist underground and surface metal/nonmetal mining operations in reducing worker exposure to respirable silica dust. The controls discussed in this handbook range from long-used controls which have developed into industry standards, to newer controls, which are still being optimized. (PDF, 3040 KB, 2010-05)

 (PDF, 2516 KB, 2004-12)

An air quality survey was conducted at a precious metals refinery in order to evaluate worker exposures to airborne metals and to provide detailed characterization of the aerosols. (PDF, 471 KB, 2010)

NIOSH research on reducing heavy equipment operator exposure to dust is detailed in this report. (PDF, 134 KB, 2009-05)
                                                       

During a recent NIOSH field evaluation of a newly designed filtration and pressurization system for an enclosed cab of a surface drill, it was determined that the drill operator's respirable-dust exposure was significantly increased during time periods when the cab door was opened to manually guide another section of drill steel into place. An alternative method is being investigated to guide the drill steel in place in order to eliminate this increased exposure. (PDF, 817 KB, 2007-10)

This paper reports US Bureau of Mines (USBM) research on the explosibility of coal dusts. The purpose of this work is to improve safety in mining and other industries that process or use coal. (PDF, 861 KB, 1996-01)

Particulate exposure from air pollution increases the risk of ischemic heart disease (IHD) mortality. Although coal miners are highly exposed to coal dust particulate, studies of IHD mortality risk among coal miners have had inconsistent results. Previous studies may have been biased by the healthy worker effect. Methods: We examined the dose-response relationship between cumulative coal dust exposure, coal rank, and IHD mortality among a cohort of underground coal miners who participated in the National Study of Coal Workers' Pneumoconiosis. (PDF, 249 KB, 2011)

This paper describes the findings of a project that was developed to systematically document how workers react to wearing the PDM and evaluate how it is used on the job.  (PDF, 188 KB, 2008-04)

This report on the third series of coal-dust explosibility tests at the experimental mine near Bruceton, PA., about 12 miles from the Pittsburgh experiment station of the bureau, covers the years 1919 to 1924, inclusive. (PDF, 3148 KB, 1927)

This paper presents the results of a hypothetical cost comparison analysis of the PDM with the current MSHA-required coal mine dust personal sampling unit (CMDPSU).  (PDF, 340 KB, 2008-07)

This paper presents the results of a side-by-side comparison of the respirable dust dosimeter and gravimetric respirable dust sampler in a controlled experimental environent in the laboratory and in underground coal mines under normal operating conditions. (PDF, 272 KB, 2001-01)

Describes a computer program developed by NIOSH for estimating the air quantity needed to dilute diesel particulate matter in underground large opening mines. (PDF, 202 KB, 2004)

This paper describes NIOSH conducted laboratory experiments to examine the effect of spray type, spray pressure, machine body blocking sprays, and scrubber airflow on dust and gas levels while using a 12.2 m (40 ft) exhaust ventilation curtain setback from the face. (PDF, 150 KB, 2010)

This document supports Code of Federal Regulations (CFR) proposed rule making for the CPDM. (PDF, 61 KB, 2008)
                                                            

NIOSH initiated the development of a fixed-site machine-mounted continuous respirable dust monitor. The technology chosen for monitor development is the Rupprecht and Patashnick Co., Inc. tapered element oscillating microbalance. Laboratory and in-mine tests have indicated that, with modification, this sensor can meet the humidity and vibration requirements for underground coal mine use. (PDF, 1560 KB, 1997)

In response to an MSHA task group recommendation, the National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Center, initiated the development of a fixed-site machine-mounted continuous respirable dust monitor. (PDF, 418 KB, 1996)

A study of dust control technology and practices to reduce the occurrence of lung diseases in miners. (PDF, 1689 KB, 2001)
                                                  

This investigation tested the feasibility of enhancing existing engineering dust controls by mounting a simple barrier on a longwall shearer that separated the operators from the cutting drums. (PDF, 267 KB, 2009-12)

This paper presents an overview of dust controls typically utilized in underground US coal mines and an update on ongoing NIOSH PRL research efforts that are evaluating new control technologies. (PDF, 1285 KB, 2008)

Information regarding adverse health effects resulting from exposure to respirable coal mine dust was reviewed as a basis for the development of new occupational safety and health standards. Recommendations are provided concerning respirable coal mine dust sampling to monitor worker exposure, the proper use of personal protective equipment, and medical screening and surveillance examinations. (HTML, KB, 1995-09)

Since 1982, standard calibration materials recommended for respirable crystalline silica analysis by the Mine Safety and Health Administration (MSHA) P7 Infrared Method and the NIOSH X-ray Diffraction (XRD) Analytical Method 7500 have undergone minor changes in size distribution. However, a critical assumption has been made that the crystalline silica in ambient mine atmosphere respirable dust samples has also remained essentially unchanged in particle size distribution. The objective of this work is to compare recent particle size distributions of underground coal mine dust and the silica component of these dusts with estimated aerodynamic particle size distributions of calibration standard materials MIN-U-SIL 5, Berkeley 5, and SRM 1878 used by two crystalline silica analysis techniques. (PDF, 68 KB, 2006-01)

Results from underground dust surveys to identify current operating practices and the types of controls being used at longwall operations are presented as an update on longwall dust control technology and operating practices. (PDF, 337 KB, 2007)

This report focuses on two areas of research to lower miners' exposure to respirable dust at surface operations. These areas deal with enclosed cabs methods to lower dust levels at surface drills. (PDF, 2569 KB, 2001-09)

This article examines the spatial variability of dust concentrations within a coal miner´s breathing zone and the impact of sampling location at the cap lamp, nose, and lapel. (PDF, 172 KB, 2007-08)

NIOSH recently investigated the performance of a lower-pressure, water-powered in-line series spray scrubber for removing localized airborne dust emitted at the source. Results showed noticeable improvements in airborne dust capture efficiency through the operation of multiple in-line series hollow cone spray nozzles within a round duct of pipe at the same water pressure as a single spray. (PDF, 1015 KB, 2006)

Although structure type and building material were not viewed as significant factors affecting the health of employees in mineral processing facilities when they were built, NIOSH has found that building type can impact respirable dust and noise levels. NIOSH performed a study in which it evaluated three building types: masonry, an open-structure design, and a steel-sided design. (PDF, 1541 KB, 2007-07)

This article summarized results of research conducted by the National Institute for Occupational Safety and Health (NIOSH) at its Pittsburgh Research Laboratory. The objective of this work was to determine the correlation between the mass (M) of respirable coal and limestone dusts collected on 25-mm-diameter glass fiber filters mounted in cassettes and the increase in differential pressure that develops across the filters when drawing at constant air flow. (PDF, 720 KB, 2002-02)

NIOSH recently performed a laboratory study to evaluate which factors on an enclosed-cab filtration system are most significant. (PDF, 147 KB, 2009-10)
                       

NIOSH conducted a series of laboratory tests using a roof bolting machine to assess the respirable dust capture ability of a water exhaust conditioner as compared to the standard exhaust muffler. (PDF, 119 KB, 2010)

Dust surveys were conducted to determine factors affecting belt entry dust levels and how using belt air to ventilate work areas affected dust exposures. (PDF, 4300 KB, 1992)

Throughout the mining and processing of minerals, the mined ore undergoes a number of crushing, grinding, cleaning, drying, and product sizing operations as it is processed into a marketable commodity. These operations are highly mechanized, and both individually and collectively these processes can generate large amounts of dust. If control technologies are inadequate, hazardous levels of respirable dust may be liberated into the work environment, potentially exposing workers. Accordingly, federal regulations are in place to limit the respirable dust exposure of mine workers. Engineering controls are implemented in mining operations in an effort to reduce dust generation and limit worker exposure. (PDF, 14308 KB, 2012)

This paper presents an update on longwall dust control technology and practices in the U.S. It summarizes the results of NIOSH dust surveys conducted at longwalls throughout the country to document the types of controls that are being used and to quantify the relative effectiveness of these controls. It also presents longwall dust parameters provided by mine operators to the Mine Safety and Health Administration (MSHA) to assess the status of dust control technology being used throughout the industry. (PDF, 2158 KB, 2006)

This paper summarizes existing dust control technologies routinely being used in underground coal mine operations, and provides a review of new controls that are being pursued. (PDF, 368 KB, 2007)

Many types of heavy equipment used in the mining and construction industries use enclosed cabs to protect equipment operators from dust and noise exposure. A cooperative research study with a mining company and a cab filtration company was conducted to evaluate the effectiveness of retrofitting an older surface drill with two controls to lower the drill operator's respirable dust exposure. (PDF, 4166 KB, 2001-04)

This research evaluated the quality of dust dispersion in the Siwek 20-L chamber using Pittsburgh coal, Gilsonite, and purple K dusts. (PDF, 581 KB, 2010-01)

The objectives of this work are to 1) evaluate the performance of the P7 method on field samples of low quartz mass loadings, 2) evaluate the magnitude of dust mass spatial variability within an enclosed cab environment, and 3) estimate the subsequent propagation of error in calculating the percentage of quartz over a broad range of mass and quartz filter loadings at a surface coal mine. (PDF, 883 KB, 2001-09)

A series of laboratory evaluations examined the impact of water spray pressure, curtain setback distance, and external and underboom spray use for controlling respirable dust levels and sulfur hexafluoride tracer gas concentrations around a continuous mining machine. (PDF, 132 KB, 2006)

This paper discusses NIOSH studies evaluating the impacts of emerging technologies that may reduce dust exposures for continuous mining and roof bolting personnel. These technologies include use of a wet-head cutting drum on a continuous mining machine, a canopy air curtain for protecting roof bolting personnel, and mist drilling technology for controlling respirable dust exposures of bolting personnel. (PDF, 292 KB, 2006)

The work presented in this paper focuses on the relationship between the PDM and respirable dust concentrations currently measured by a coal mine dust personal sampler unit utilizing a 10 mm Dorr Oliver nylon cyclone. (PDF, 228 KB, 2008-01)

NIOSH is conducting full-scale laboratory studies to evaluate dust liberation and control for dust generated by shearer cutting. (PDF, 650 KB, 2001-10)
                       

This analysis will indicate safe following distances for haul trucks and other heavy equipment to avoid overexposure to respirable dust from the lead haul truck. (PDF, 722 KB, 2005-02)

This work presents the findings from NIOSH field and laboratory studies comparing respirable dust levels on mist drilling roof bolter machines to dust levels measured on machines using a conventional vacuum drilling system. (PDF, 290 KB, 2008-12)

Data collected for this study indicate that 20-mesh screens should be cleaned for every 40 ft of advance because 22% of the deep-cut sequences surveyed for this study experienced a 20% to 35% decrease in scrubber airflow over the course of the cut. For blowing face ventilation, field and laboratory data indicate that maintaining a proper curtain-to-scrubber airflow ratio of 1.0 and a curtain setback distance that allows the miner operator to stand at the mouth of the curtain helps control dust. Curtain airflows should be measured before activation of the scrubber regardless of ventilation type (exhausting or blowing) to avoid erroneously overinflating the ratio. The curtain setback variance should be greater than the maximum cutting depth to allow miner operators to maintain their position at the mouth of the curtain when the miner is fully extended into the cut. Greater curtain setback distances associated with deep-cutting methods may result in cuts that do not require ventilation curtain, such as the initial heading developments beyond the last open crosscut. For these cuts, dust levels were generally lower during development of deep cuts when compared to regular cuts. However, adequate ventilation of cuts without ventilation curtain is dependent on a properly functioning scrubber. Dust levels on the bolting faces did not appear to be affected by the longer cycles associated with deep-cut mining practices when curtain airflow was measurable and the curtain was periodically advanced in sync with the bolting machine. (PDF, 4319 KB, 2011)

This paper examines methods for limiting occupational silica exposures for roof bolting personnel in underground coal mining. It also evaluates a metal rake, a flexible insert, and a rigid insert for cleaning the roof bolter dust collector box. (PDF, 393 KB, 2002-02)

The results of this study by NIOSH have served to provide performance data in support of the procedures described in the international standard methods, for which such results were previously unavailable in the peer-reviewed literature. (PDF, 117 KB, 2009-02)

Occupational exposure to high levels of respirable quartz can result in respiratory and other diseases in humans. The Mine Safety and Health Adminstration (MSHA) regulates exposure to respirable quartz in coal mines indirectly through reductions in the respirable coal mine dust exposure limit based on the content of quartz in the airborne respirable dust. (PDF, 258 KB, 2012)

The SKC, Inc., Dust Detective (SKCDD) is an affordable, person-wearable, real-time dust monitor. The relationship of dust concentrations measured by personal gravimetric samplers to those measured by the SKCDD was determined in a laboratory aerosol chamber. Results demonstrated that the SKCDD is a viable alternative means for measuring dust. While it provides accurate measurements for specific coal types, it requires correction factors (which still need to be calculated) for other coal types. (PDF, 159 KB, 2006)

This paper describes field tests conducted by NIOSH to evaluate the effectiveness of a wet head continuous mining machine for reducing dust exposure for continuous miner operators. (PDF, 163 KB, 2010)

The increased effectiveness of a two-phase spray system (TPSS) over a single-phase system (SPSS) for dust suppression is reported in several laboratory studies. (PDF, 723 KB, 2000-09)

The focus of this work is drill shroud dust leakage and the relationships of various drill parameters on this leakage. Given that exposures of surface coal mine rock drillers to respirable crystalline silica are of particular concern, substantial reductions of airborne silica dust during drilling may be estimated and achieved through use of the analysis presented. (PDF, 292 KB, 2008-09)

Explosion characteristics such as the minimum explosible concentration and the rock dust inerting requirements were measured for various combustible dusts. The explosion resistance characteristics of seals was also evaluated. (PDF, 2134 KB, 2000-05)

During the 20th century, the increased emphasis on worker health and safety and the advent of new mining equipment and methods led to many changes in mine face ventilation practices. This paper examines factors that had a significant influence on mine face ventilation design during the past century. (PDF, 843 KB, 2007-02)

Airborne respirable dust surveys were conducted at six surface coal mines to investigate the effectiveness of dust control methods used on rotary rock drills and bulldozers. (PDF, 810 KB, 1999)

Operator cabs on a front-end loader and a rotary rock drill were retrofitted with ceiling mounted heating/AC units and air filtration systems. Subsequently, surface coal mine field studies were conducted to evaluate the respirable dust protection these retrofitted cab systems offer to the equipment operator. Results indicate that achieving positive interior cab pressurization with retrofitted cab filtration systems is a key element in their dust control effectiveness. (PDF, 930 KB, 2000-08)

In previous studies, an air-blocking shelf has been shown to be successful in reducing respirable dust leakage from the drill shroud in a laboratory setting. Dust reductions of up to 81 percent were achieved with the shelf under operating conditions consisting of a 1.9:1 collector-to-bailing airflow ratio and a 5.1-cm gap between the shroud and ground. Recent research focused on evaluating the shelf on two actual operating blasthole drills, in much more severe environments. In the field, the shelf reduced dust levels in the areas surrounding one operating blasthole drill by 70 percent. Dust reductions measured in the immediate vicinity of the shroud were reduced by 66 percent at one mine and 81 percent at the other mine. These field tests confirm that the air-blocking shelf is useful for reducing respirable dust generation from blasthole drills. (PDF, 443 KB, 2011)

Full-scale testing and results are described for an automated system that continuously monitors the accumulation of coal dust in mine entries. (PDF, 234 KB, 1998-05)

This handbook describes effective methods for the control of mineral dusts in mines and tunnels. It assumes the reader is familiar with mining. The first chapter deals solely with dust control methods, regardless of the application. It is a brief tutorial on mining dust control and will be of help to the reader whose dust control problem does not conveniently fit any of the mining equipment niches described in later chapters. (PDF, 2776 KB, 2003-06)

This truck haulage dust study showed that primarily wind, distance, and road treatment conditions notably affected the dust concentrations at locations next to, 50 ft from, and 100 ft away from the unpaved haulage road. (PDF, 549 KB, 2007-10)

Proper measurement of dust particle concentration is a critical step toward the elimination of dust-related occupational disease. This paper examines the development of dust sampling methods in U.S. coal mines, with emphasis on the benefits of personal sampling and on recent developments that permit real- time assessment of dust exposure. (PDF, 460 KB, 2002)

This paper presents the results of laboratory testing to determine if the Installation of a horizontal air blocking shelf around the inside perimeter of a surface mining drill deck will improve dust capture.  (PDF, 296 KB, 2009)

This paper describes a recent research project initiated by NIOSH which identified improvement of the drill shroud design as one of its main objectives for reducing the exposure of surface miners to respirable dust. (PDF, 337 KB, 2008)

This paper discusses the geochemical analyses which were applied in an effort to identify the specific source rock of respirable quartz dust in coal mines. (PDF, 829 KB, 2009-04)

This paper investigates the influence of air velocity and shield advance rates on respirable dust levels. Also discussed are engineering controls currently used to reduce shield dust and alternative controls being investigated by NIOSH. (PDF, 211 KB, 2010-04)

The Bureau of Mines has recorded a number of different background dust sources that significantly contaminate the air breathed by bag machine operators. To keep bag operator exposure within acceptable dust levels established by the Mine Safety and Health Administration, U.S. Department of Labor, the significance of these background sources must be realized, and the sources must be identified and controlled. (PDF, 2189 KB, 1986)

Previous research on continuous mining operations has shown that significant interactions exist between dust-control parameter application and the resulting respirable dust levels. However, simply increasing the level of the controls does not guarantee a reduction in respirable dust levels. Full-scale laboratory tests are being conducted to provide information to longwall operators that would assist them in selecting control parameters to reduce dust levels for mine-specific conditions. (PDF, 752 KB, 2002)

NIOSH researchers have demonstrated that mine-wide ventilation in large-opening stone mines can be improved by using low-pressure, high-volume propeller fans and constructing stoppings in key locations to direct and control airflow. In light of these findings, a comparative study was conducted to determine if a portable diesel-powered propeller fan could perform more efficiently for dust dilution and transport than an axial vane fan for localized ventilation. Results showed an improvement with the propeller fan to dilute both the respirable dust and the respirable silica dust around the dump/crusher facility. (PDF, 752 KB, 2006-06)

A unique method to collect and measure respirable coal mine dust using the tapered element oscillating microbalance has demonstrated potential use as an effective engineering tool to help dust control. (PDF, 166 KB, 2004-12)

This article describes the results from analysis of open-face samples which suggest that the new formulations for PDM filters have fully addressed the analytical obstacles that existed with the original filter design. (PDF, 340 KB, 2008-05)

NIOSH researchers have developed a model to describe airborne respirable dust (ARD) generation on surface coal mine drills. (PDF, 284 KB, 2008-09)
                            

This study tests the ability of a new air nozzle system, located under the drill deck shroud, to improve the dust capture of the drill deck shroud. (PDF, 673 KB, 2010-01)

A recent report evaluating silica exposure levels in the metal/nonmetal mining industry noted that bag packaging and loading are some of the occupations at the greatest risk. In addition to dust problems, the bag-stacking process is labor intensive, making lost-time injuries common due to back fatigue and strains. (PDF, 414 KB, 2000-04)

NIOSH conducted a strategic planning effort to identify those areas in mining with the greatest research needs. In response, the Pittsburgh Research Laboratory (PRL) has implemented a multi-faceted research program to improve silica dust control for these problematic commodities and occupations. A review of silica compliance trends, PRL silica research programs, and recent control technology developments are provided here. (PDF, 1703 KB, 2002-02)

During the last few years, PRL researchers have conducted research related to the following goals: improving protection provided by enclosed cabs on mobile surface mining equipment, reducing dust generation from surface drills, reducing dust levels in iron ore operations, and developing a new method to clean dust from workers' soiled clothes. A description of each of these controls and subsequent dust reductions quantified through site surveys is provided. (PDF, 924 KB, 2007)

The objective of the research was to cost-effectively increase the air cleaning volume and improve dust capture efficiency of an off-the-shelf dust collector with a larger motor and blower. (PDF, 522 KB, 2008)

This study examines the accuracy of area sampling for measuring the dust exposure of mining machine operators at coal mine working faces. The work was prompted by the development of a prospective new type of dust sampling instrument called the machine-mounted continuous respirable dust monitor (MMC-RDM). (PDF, 799 KB, 2002-02)

The effect of wind speed upon aerosol penetration into an idealized enclosure was studied. (PDF, 474 KB, 1999-02)
                                                             

This paper presents the results to date of a NIOSH investigation into the possible causes that would account for the observed higher trends in CWP disease progression through review, data analysis, and in-mine surveying. (PDF, 241 KB, 2009)

Laboratory testing and results are presented where five bituminous coals were prepared and processed through a double roll crusher located in a low-velocity wind tunnel. The results indicate that a combination of several factors are associated with airborne respirable dust generation. (PDF, 266 KB, 1998-10)

Two types of airflow splitting methods for improving longwall dust control were investigated by NIOSH's Pittsburgh Research Laboratory. These methods included a transducer mesh barrier and a staged spray barrier system to confine the shearer-generated dust to the coal extraction side of the longwall face while maintaining a cleaner split of airflow on the opposing worker walkway side of the longwall face. (PDF, 1293 KB, 1999)

NIOSH experimentally investigated various factor effects on cab air filtration system performance. This paper describes the laboratory experiments which were performed on an enclosed cab test stand examining the independent factor effects of intake filter efficiency, intake filter loading (airflow resistance), intake air leakage around the filter, recirculation filter use, and wind on cab performance. (PDF, 900 KB, 2008-11)

This paper presents the results of NIOSH laboratory and field tests to evaluate the effectiveness of dust collector bags for reducing dust liberation and operator exposure from a roof bolter's dust collection system. (PDF, 742 KB, 2008-07)

This report includes the theory of operation, description, and the performance of the Personal Dust Monitor (PDM) compared to gravimetric-based reference dust sampling methods and laboratory verification of the instruments accuracy. There is also a detailed underground evaluation that includes measurement of the instruments precision, durability under mine use conditions, and the functionality of the instrument when used by miners. (PDF, 1128 KB, 2006-09)

Testing at NIOSH assessed the effectiveness of a canopy air curtain for controlling occupational exposures to respirable silica and coal dusts. (PDF, 303 KB, 2001-06)

Assessment of exposure to occupational dusts is a first step in reducing exposures to harmful dust concentrations. A new type of respirable dust sampler was developed and compared side-by-side to personal gravimetric samplers in the laboratory. (PDF, 706 KB, 2000-01)

Laboratory test to simulate dust liberation during shield movement were conducted. (PDF, 707 KB, 2001-02)
                                                                     

NIOSH experimental investigation results indicate that the intake filter efficiency and recirculation filter were the two most influential factors on cab protection performance. (PDF, 775 KB, 2009-01)

A series of controlled laboratory tests were conducted in a test stand simulating shield dust entrainment to evaluate changes in airborne respirable dust levels at different air velocities. (PDF, 223 KB, 2001-06)

A cooperative research effort was established to lower respirable dust levels in an iron ore grinding and concentrator plant. The most significant improvement was realized by changing the ventilation profile throughout the entire facility. Another successful modification was to improve the sealing of a reclaim tunnel to the outside and to barricade the access point from the reclaim tunnel to the concentrator plant. These two modifications illustrate the impact that improvements in ventilation can have on lowering respirable dust concentrations in iron ore processing facilities. (PDF, 294 KB, 2006)

The National Institute for Occupational Safety and Health (NIOSH) has developed a machine-mounted continuous respirable dust monitor (MMCRDM) based on the tapered-element oscillating microbalance (TEOM®) sensing technology. The sensor can be mounted on mobile mining equipment and can continuously and accurately measure respirable coal mine dust mass concentrations despite the rigors of the underground mine environment. The display shows dust levels averaged over various intervals and a graph of the shift average as a function of time. The monitor also incorporates several automatic diagnostic functions to detect system failure or tampering. (PDF, 1759 KB, 1997-10)

This paper shows that ventilation pressure at the section mouth and stopping resistances are the two primary considerations for the maximum length gateroads that can be developed using intake belt air. (PDF, 72 KB, 2009-08)

This article reviews various dust control technologies developed over the years at the Pittsburgh Research Laboratory of the National Institute for Occupational Safety and Health (NIOSH) to provide various options and alternatives to lower bag machine operators' and bag stackers' dust exposures. (ASP, KB, 2000-10)

A summary of aerosol measurement technology currently used in the U.S. mining industry as it relates to regulation, research and personal exposure monitoring. (PDF, 694 KB, 2001-09)

This NIOSH paper documents coal miners´ reactions to the new Personal Dust Monitor (PDM), and how they make use of the information th PDM provides. (PDF, 2423 KB, 2007)

This report summarizes a field study by NIOSH that documented the reactions of 30 miners at 4 underground coal mines concerning the use of personal dust monitors (PDMs) and how they make use of the information it provides. (PDF, 285 KB, 2008-02)

Airborne soot particles have a significant effect on atmospheric chemistry and their detailed properties are thus of interest to researchers. There are many different types of soot with a variety of shapes and chemical composition. This paper presents new information regarding the characterization of soot from different (known) sources, providing insight into identification of fresh and aged soot particles observed in the atmosphere. (PDF, 372 KB, 2010-03)

Discusses a simple, quick fix to reduce dust from blasthole drills by installing a dust collector shroud. This can reduce respirable dust concentrations at the dust collector dump point by more than 63%. (PDF, 310 KB, 2004-06)

Dust from worker's clothes has been shown to be a problematic source of personal dust exposure. A recently completed effort between NIOSH and Unimin Corp. has resulted in a quick and effective way to clean worker clothing. Field testing indicated that the manifold cleaned the clothes 10 times faster and removed 50% more dust than cleaning methods used by workers today. (PDF, 1019 KB, 2006)

The compliance sampling method for coal mine dust in the United States has not changed appreciably in the last 30 years. A call for more frequent sampling with immediately available results is leading to new instruments that may supplement or replace the existing sampler. (PDF, 321 KB, 2001-01)

Exposure to airborne respirable crystalline silica dust can lead to silicosis, a debilitating lung disease. On surface coal mining and construction sites, blast hole drills are notorious sources of airborne respirable dust that may contain significant amounts of silica. (PDF, 7376 KB, 1998-11)

Bag stackers who use semi-automated palletizing machines and air slides may be exposed to high concentrations of dust. To reduce dust exposure, use an exhaust ventilation system in conjunction with an envelope of clean air over the bagstacker provided by an overhead air supply. (PDF, 515 KB, 2001-07)

A study was conducted examining the risk of silica dust exposure in mine workers exposed to continuous miners equipped with flooded bed scrubbers. (HTML, 8 KB, 1997-08)

The importance of controlling respirable dust and methane gas levels in underground coal mining cannot be underestimated. This paper reviews practical applications of water sprays and dust scrubbers to control respirable dust and methane gas on continuous miner faces. (PDF, 337 KB, 2000)

This article describes the first comprehensive survey since the 1920s to determine the range of coal particle sizes found in dust samples collected from intake airways of US coal mines.  (PDF, 215 KB, 2008-05)

This paper discusses a limited number of control technologies to reduce or eliminate harmful respirable dust. (PDF, 160 KB, 2009)
                                          

Because of the need to provide short-term or real-time estimates of worker respirable dust exposure, porous foam may be a viable classification media for a low flow rate, disposable respirable dust sampler for use in the coal mining industry. (PDF, 557 KB, 2000-07)

This paper presents the results of testing of the Dynamic Component Program model with the ISC3 model of predicting dispersion of dust from haul trucks at two surface mine sites. (PDF, 2045 KB, 2003)

The Thermo personal DataRam (pDR) is an instantaneous sampler that uses light-scattering technology to provide relative measures of airborne respirable dust. The pDR can be used in active and passive modes to measure respirable dust levels. Tests were conducted to evaluate the sampling performance of active and passive pDR operation relative to each other and against a gravimetric sampler (the accepted standard for respirable dust measurement). The purpose of the test was to determine if the pDR can be used effectively in the passive mode in higher velocity airflows. (PDF, 2476 KB, 2007)

The Thermo-MIE personal DataRAM dust monitor (pDR) is a light-scattering instrument approved for use in gassy underground mines by the U.S. Mine Safety and Health Administration (MSHA). However, the use of light-scattering monitors has been inhibited by concerns about inaccurate readings resulting from changes in dust size distribution and composition, as well as concerns about the impact of moisture in the mine air. Because of this concern, the National Institute for Occupational Safety and Health (NIOSH) evaluated the pDR using available data from laboratory tests and mine surveys. (PDF, 165 KB, 2006)

A personal dust monitor (PDM) was developed to measure respirable coal mine dust mass to provide accurate exposure data at the end of a work shift. In tests, the PDM demonstrated that it was convenient to wear, robust, provided accurate data, provided timely data that could be used to prevent overexposure, and was easy to use. (PDF, 408 KB, 2004-06)

The personal dust monitor (PDM) is a sampling device developed for measuring the personal exposure to coal mine dust of mine workers. (PDF, 494 KB, 2002-10)

This paper concludes a five-year program on research into the use of a portable X-ray fluorescence (XRF) analyzer for analyzing lead in air sampling filters from different industrial environments, including mining, manufacturing and recycling. (PDF, 208 KB, 2007-11)

The paper discusses how the Diesel Particulate Matter (DPM) monitors have performed within the underground mine environment in evaluating DPM during the various phases of longwall moves. (PDF, 156 KB, 2009)

An alternative method to the original system developed by NIOSH and Unimin Corporation to provide for a stand-alone clothes cleaning system has been developed to quickly, effectively, and safely remove dust from the clothing of a worker without dust exposure to the worker, the work environment, or co-workers during the cleaning process. (PDF, 268 KB, 2008)

This report discusses a cooperative research study performed on a surface drill retrofitted with a new pressurization and filtration system. Respirable dust concentrations were substantially reduced from 0.64 mg/m3 during pre-testing to 0.05 mg/m3 during post-testing with the new system, representing a 92% reduction in dust levels in the drill cab. (PDF, 224 KB, 2002-02)

Discusses a cooperative research effort to lower respirable dust levels in an enclosed cab on an older surface drill at a silica sand operation. A number of modifications were incorporated into the drill's filtration and pressurization system, as well as in other areas, to improve its design and performance. The goal was to identify cost-effective improvements that could be implemented on all types of enclosed cabs to lower respirable dust concentrations. (PDF, 1999 KB, 2005)

The design and evaluation of two total mill ventilation systems are described. Both systems proved to be very effective at reducing respirable dust levels in a cost-effective manner, were easy to install, and required minimal maintenance. (PDF, 876 KB, 1993)

A quick, safe, and effective method has been developed that allows workers to clean their dust laden work clothing periodically throughout the day. The newly designed clothes cleaning process has potential application to any industry where workers' clothing becomes contaminated with most any type of dust or product. (PDF, 8726 KB, 2007-04)

Longwall mining equipment has improved dramatically over the last 15 years. Although significant gains in longwall dust control have been made, they have been challenged by significant increases in coal extraction rates resulting in more dust being generated. (PDF, 365 KB, 2001-01)

The U.S. Bureau of Mines investigated the relationship of bituminous coal seam parameters and the amount of respirable dust generated at longwalls. (PDF, 1699 KB, 1992)

Small scale laboratory pulverizing experiments were performed on humidified coal material sieved to size 6.35 mm (0.250 in) and below to eliminate effects due to inherent planes of weakness (cleats or joints). Experimental factors studied include the coal seam proximate analysis constituents, the breakage-induced electrostatic field of airborne dust, and the specific airborne dust generated. (ASP, KB, 2000-04)

The importance of controlling respirable dust and methane gas levels in underground coal mining cannot be underestimated. While respirable dust can significantly affect the occupational health of underground coal miner, methane gas accumulations pose significant safety concerns for these same workers. (PDF, 263 KB, 2001-01)

A U.S. Bureau of Mines investigation of Fourier transform infrared (FTIR) spectroscopy for on-filter analysis of respirable dust. (PDF, 2125 KB, 1992)
                      

This study examined the potential for coal mine roof bolter dust to be a source of a worker's exposure to respirable quartz. (PDF, 95 KB, 2010)
                           

A Review of Occupational Silica Exposures on Continuous Mining Operations. (PDF, 638 KB, 2000)
                                                                             

The work presented in this paper focuses on providing a more accurate conversion multiplier than previously reported in the literature, using an independent direct comparison of the 2.0 L min^-1 Dorr-Oliver cyclone (BMRC equivalent) and the 1.7 L min^-1 Dorr-Oliver cyclone. (PDF, 381 KB, 2009-03)

This paper briefly discusses the current status of some miner health-related issues, including those involving coal dust, silica dust, diesel particulate matter, asbestos, noise, lead, welding fumes, and skin disorders, as well as research and other activities aimed at protecting miners from occupational illnesses and disease. (PDF, 398 KB, 2003)

This report presents the various dust dispersion models that have been developed specifically for the mining industry. (PDF, 303 KB, 2005)
                                 

The NIOSH Pittsburgh Research Laboratory is involved in research to identify silica dust sources and generation in underground metal/nonmetal mines. A summary of sampling procedures, resulting data, and methods being investigated to reduce silica dust will be discussed.  (PDF, 460 KB, 2002)

The ultimate goal of this research is to develop control technologies to reduce worker exposure to respirable silica dust. Dust surveys were conducted in an underground limestone and gold mine to investigate silica dust sources, generation levels, and controls being used. A summary of the mining operations, sampling procedures, resulting data, and suggested methods to improve the dust control will be provided. (PDF, 885 KB, 2002)

This pamphlet provided information on what rock drillers can do to protect themselves from silica dust, which may cause silicosis. The role of exposure to silica dust in the development silicosis was discussed. (HTML, KB, 1997)

In response to the Mine Safety and Health Administration's request, the U.S. Bureau of Mines investigated several sensor technologies for continuously monitoring respirable coal mine dust. One of these technologies is the tapered element, oscillating microbalance. (PDF, 377 KB, 1996-01)

NIOSH conducted dust surveys at 13 longwalls operating throughout the U.S. and collected information to: identify current operating practices on these longwalls, identify the types of dust controls in use, document the levels at which these controls are being applied, and measure the respirable dust levels present. This data was analyzed to quantify the dust levels generated by the major sources on the longwall section and to evaluate the relative effectiveness of the control technologies in use. (PDF, 1805 KB, 1997)

This paper describes a practical approach for implementing stochastic determination of gob gas ventholes production performances and for generalizing the prediction capability of deterministic models. (PDF, 610 KB, 2010)

This study focuses on how hygroscopic properties, deliquesence relative humidity (DRH) and hygroscopic growth factor (GF) of nanoparticles vary with their size and structural properties. (PDF, 296 KB, 2009-01)

This paper discusses the role of ventilation modeling in evaluating primary escapeway pressurization in a three-entry development system to improve emergency escape in a coal mine using belt air. (PDF, 249 KB, 2010)

Health research studies have identified that the risk of developing and the severity of CWP are directly related to the amount of respirable dust exposure and the coal rank. The Pittsburgh Research Laboratory is pursuing more in-depth studies of coal charging characteristics and the use if water additives (surfactants) for water spray systems to improve dust suppression and reduce miner dust exposure. (PDF, 281 KB, 2000)

This paper summarizes the results of research that has been done on respirable dust control for surface mine blasthole drilling operations. Additionally, past dust control research for drilling operations of both underground and surface mines completed by the U.S. Bureau of Mines, created in 1910 and incorporated into NIOSH in 1997, is reviewed. (PDF, 571 KB, 2008)

This article outlines research by the National Institute for Occupational Safety and Health (NIOSH) on using whole-plant ventilation in two mineral processing operations to reduce respirable dust levels. (PDF, 460 KB, 1998-01)

The USBM's current approach to air splitting consists of using a polyester mesh partition to overcome the visibility problems of a solid barrier. (PDF, 56 KB, 1994-03)

A method is described to increase the dust-control effectiveness of the Rotoclone dry-dust collection systems used on surface coal mine drills. (PDF, 56 KB, 1994-10)

Dust collector discharge shrouds were used to reduce airborne respirable dust generated from emptying dry dust collectors on small truck-mounted drills at surface coal mines. (PDF, 56 KB, 1995-03)

A machine-mounted continuous respirable dust monitor is discussed that can accurately monitor, display, and record concentration levels of respirable coal mine dust in mines for extended periods. (PDF, 131 KB, 1997-07)

Higher efficiency air filters provide good dust control for the equipment operator, but tend to accumulate dust more quickly than lower efficiency air filters. (PDF, 193 KB, 2001-02)

Floor heaters are identified as contributing to dust levels in enclosed cabs. Two methods are identified to minimize the problem of dust generation inside cabs. (PDF, 539 KB, 2001-03)

A method is described to reduce the dust generated from soiled floors within enclosed operator cabs. (PDF, 442 KB, 2001-03)
                                                   

The growing realization of the importance of a healthy work environment along with increased regulations will require many stone mines to implement new ways to improve ventilation. In-place stone stoppings are one option. (PDF, 152 KB, 2002-12)

A new clothes-cleaning process was developed that uses a compressed air nozzle manifold to blow dust from the worker's clothes in an enclosed booth. The process cleans work clothes 10 times faster and removes up to 50% more dust than the single air hose or vacuuming methods. Average cleaning time is less than 20 seconds. (PDF, 649 KB, 2005-05)

This research showed that a tight shroud is very beneficial for the drill dust collection system, while improvements for a leaky shroud could be achieved with collector-to-bailing airflow ratios >= 3:1 and/or by relocating the inlet. (PDF, 84 KB, 2005-10)

Objective: To evaluate the effectiveness of dust collector bags for reducing dust liberation from a roof bolter dust collection system. (PDF, 475 KB, 2007-02)

NIOSH has investigated various cab filtration system factors on a basic HVAC system in the laboratory to evaluate their effects on overall cab dust protection performance. The factors experimentally investigated were intake filter efficiency, intake air leakage, intake filter loading (filter flow resistance), recirculation filter use, and wind penetration. The use of the recirculation filter remarkably improved the average cab protection factor by an order of magnitude over what was provided by the intake filter. (PDF, 130 KB, 2007-10)

National Institute for Occupational Safety and Health (NIOSH) has been performing research to retrofit cabs with new filtration and pressurization systems in an effort to improve the air quality in enclosed cabs of older mining equipment.  (PDF, 151 KB, 2008-09)

The machine-mounted continuous respirable dust monitor (MMCRDM) is a fixed-location area sampling device developed for possible use at the working face of an underground coal mine. decades. Recently, an extensive series of laboratory and underground tests was conducted by NIOSH with the cooperation of MSHA and coal operators to test the performance of the MMCRDM. (PDF, 312 KB, 2001-06)

Researchers at the National Institute for Occupational Safety and Health (NIOSH) have long used stationary tapered element oscillating microbalances (TEOMs®) in laboratory settings. They have served to assess the mass concentration of laboratory-generated particulates in experimental dust chambers and they provide a reference method for comparison with other particulate-measuring instruments. Current NIOSH research is focused on further adapting TEOM technology as a wearable personal dust monitor (PDM) for coal mining occupations. This investigation's goal is to help identify, quantify, and provide means for resolving certain TEOM-related error. The present research investigated bias caused by thermal effects on filter assemblies. (PDF, 1164 KB, 2007-07)

A laboratory study assessed the impacts of water spray pressure, face ventilation quantity, and line brattice setback distance on respirable dust and SF6 tracer gas concentrations around a continuous mining machine using a sprayfan or directional spray system. The results showed that changes in all three independent variables significantly affected log-transformed dust levels at the three operator sampling locations. (PDF, 140 KB, 2004-12)

The amount of airborne respirable dust generated from breakage of different coals varies widely. This research was conducted to identify the facets of airborne respirable dust liberation from the coal product. (PDF, 1217 KB, 2002-06)

This manuscript will discuss five different research studies conducted by the National Institute for Occupational Safety and Health (NIOSH) which use ventilation in some application to lower workers' respirable dust exposures at surface and metal/nonmetal mining operations. As federal standards for health issues continue to require lower levels in the future, engineers and health and safety specialists must investigate novel approaches to improve air quality. The goal of the research discussed in this manuscript is to provide an array of applications where ventilation can be used to reduce respirable dust exposures. (PDF, 1222 KB, 2005-07)

Supplemental water sprays were placed along the sides of a continuous mining machine to improve suppression and confinement of the dust cloud under the cutting boom to reduce downwind dust levels. Using a full-scale mock-up of a continuous mining machine, preliminary work showed that these side sprays improved suppression of the dust cloud and redistributed this cloud under the cutting head. (PDF, 849 KB, 2000-07)

Tests have been conducted by NIOSH on a newly designed device for smaller diameter drills that separates the water from the bailing air before it reaches the bit and thus provides the cost benefit of dry drilling while providing the benefit of wet drilling for dust suppression. (PDF, 2225 KB, 2007-09)

Workplace aerosol measurement, while similar to other areas of aerosol measurement, differs somewhat in application and circumstance. In most cases the bulk aerosol composition is known or can be deduced from the processes or products in use. The mass concentrations involved are typically an order of magnitude greater than those in the general environment. Finally, sampling is carried out specifically for assessing human exposure, rather than characterizing the aerosol itself or the physical or chemical processes associated with it. While philosophies and approaches may differ, there is a great deal of commonality between methods used in the workplace, and those used in other areas of aerosol measurement. Thus, techniques and applications described elsewhere in this book will frequently be directly relevant to workplace sampling. Chapters 6 to 10 and 14 are particularly pertinent, providing detailed information on approaches to aerosol monitoring, filter collection, inertial, gravitational, centrifugal and thermal sampling, and direct-reading techniques. Chapters 23, 24, 26, and 27 on nonspherical particle measurement, bioaerosol measurement, ambient aerosol sampling, and aerosol exposure measurement are all relevant to the workplace. In this chapter, the emphasis is on the basic sampling philosophies and methods used on a routine basis in the workplace and the application of direct-reading monitors in workplace aerosol measurement.  (PDF, 4617 KB, 2011)

NIOSH found that drill dust could be decreased by using wet or dry dust reduction engineering controls, enclosed cabs, and implementing a dust control program. (PDF, 213 KB, 2009-04)

NIOSH found that equipment operator exposure could be reduced by retrofitting air pressurization and filtration systems on existing cabs, using sweeping compounds on soiled floors, and implementing a dust control program. (PDF, 226 KB, 2009-04)