All Downloadable Mining Publications

The aggregates industry faces a number of challenges in the near future, including the loss of experienced mine workers due to retirement, an influx of new, inexperienced workers and more challenging mining conditions. More effective training is needed to reduce injuries of both experienced and inexperienced workers from ever increasing diverse background. The awareness and involvement of the whole workforce needs to be fostered by management, labor and government jointly identifying risk factors, selecting mining practices, implementing mining plans and engineering and administrative controls. (PDF, 6810 KB, 2003-03)

Experiments were conducted with mine conveyor belt samples in a 20-L furnace and in a laboratory fire tunnel to measure and compare the major toxic gas concentrations evolved during the combustion of the materials. The toxic gas concentrations, measured simultaneously through a multiport sampling device and treated as yield values, included hydrogen chloride (HO), hydrogen cyanide (HeN), oxides of nitrogen (NO_x treated as NO₂), and carbon monoxide (CO).  (PDF, 220 KB, 1996)

Sixty years of rockbursting in the Coeur d'Alene district has taught painful lessons and led to a number of practical advances in controlling rockburst hazards. This paper summarizes those lessons, concentrating on practical measures that have been successfully adopted to reduce hazards. (PDF, 409 KB, 2002-02)

An essential element of the Bureau of Mines electromagnetic location and communication system for trapped miners is a quantitative knowledge of the surface and above-surface electromagnetic fields created by an underground transmitter. The field solutions given in this report use approximations in which the displacement currents are negligible for low frequencies. The earth is represented by a homogeneous half-space model in which a dipole source is immersed. The vertical magnetic field equipotential contours at and above the surface are graphically mapped. The volumes of the regions bounded by these contours are directly related to the geometrical zones of signal detectability. Knowledge of the detectability zones will enable the proper search strategies to be developed for airborne detection of trapped miners. (PDF, 342 KB, 1983)

This paper discusses the application of global positioning system (GPS) data, accelerometers, and pressure transducers to provide feedback about equipment operations and identify the cause of truck jolts. (PDF, 794 KB, 2000)

Stability analyses of fractured and faulted rock masses require delineation of the position, extent, and orientation of geologic discontinuities. Recommendations are made for increasing the accuracy and precision of locations of microseismic events detected under similar field conditions. (PDF, 4026 KB, 1992)

Describes a project conducted by the Bureau of Mines in which the accurate directional drilling of a borehole was demonstrated with the objective of intercepting a designated target. The project was conducted at Navajo Dam in northern New Mexico at the request of the Bureau of Reclamation. (PDF, 2520 KB, 1987)

One of the safety and health research programs of the former U.S. Bureau of Mines Pittsburgh Research Center was the evaluation of technology that will provide remote-controlled operation of mechanized equipment in underground room-and-pillar mining. As part of this program, advanced machine navigation and control technologies were developed for underground room-and-pillar and highwall coal mining that can be applied to commercially available mining equipment. (PDF, 1542 KB, 1997)

NIOSH has developed an active proximity warning system called HASARD (Hazardous Area Signaling and Ranging Device) for warning workers as they approach known dangerous areas around heavy mining equipment and other dangerous work zones. HASARD was field tested on a Joy 12 continuous miner, a Komatsu 210 M Haulpak, and on a highwall launch vehicle. HASARD provided warnings as designed and proved to be rugged enough to withstand the harshest of production environments. (PDF, 3100 KB, 2001)

An electromagnetic (EM) system for the location of trapped mine workers at coal-mine (300 m) depths has been developed. The use of such a system in deep mines (1-km depth) requires transmission at extremely low frequencies (ELF) and a reduction in the effective noise level beyond that which can be obtained by acceptable integration times. Automatic-noise-cancellation (ANC) techniques reduce the effective noise level by combining several received signals that contain correlated noise. Such signals can be obtained either from a remote magnetic antenna or a local electric antenna. During Phase III of this program, real ELF noise data were acquired and used to test the ANC algorithms developed during Phase II. (PDF, 3135 KB, 1984)

The functional safety of programmable electronic (PE) mining systems is an international issue and concern. From 1995 to 2001, 11 PE-related mining incidents in the U.S. were reported by the Mine Safety and Health Administration. (PDF, 219 KB, 2003)

Evaluation of the "Advance and Relieve" mining method is described to determine effectiveness for conditions where high horizontal stresses caused long running roof falls resulting in hazardous conditions and the premature abandonment of panels. "Advance and Relieve" mining involves the removal of a pillar of a portion of a pillar during development, creating a cave along one side of the panel.  (PDF, 5767 KB, 2001)

Since 1981, Federal mining law has required every miner working in underground coal mines to have a self-contained, self-rescuer (SCSR) available for use in emergencies. Some miners that have escaped from fires using SCSR's have reported that they had to remove their mouthpiece to talk during escape, thus compromising the protection afforded by the SCSR. To address this problem, two-way, FM radios were built into the SCSR to improve the ability to communicate should the miners be separated over relatively short distances. (PDF, 1817 KB, 1994)

Technology is available to assist off-road dump truck drivers in monitoring blind spots near their equipment. NIOSH is evaluating systems based on radar, GPS, RF tags, and cameras. (PDF, 433 KB, 2004)

As part of an on-going study at the Spokane Research Laboratory, several new methods for monitoring slope instabilities are being investigated. This paper describes the potential adaption of systems such as interferometric synthetic aperture radar, imaging spectroscopy, and time-domain reflectometry, to slope monitoring and design. (PDF, 654 KB, 1998)

The Bureau of Labor Statistics estimates that the median age of the mining workforce is rising faster than the overall U.S. civilian labor force. The Mine Safety and Health Administration reports that the percentage of injured and ill workers who are 45 or older increased steadily from 1988 to 1998. Given this trend, health and safety programs must consider the physiological changes associated with aging when evaluating job tasks and the working environment. (PDF, 171 KB, 2000)

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)

A report on research to develop a device that alerts workers when a power line has been contacted by equipment. The approach being investigated is based on measuring electric current flow to ground through a machine during a line contact. (PDF, 275 KB, 2001)

Discusses the evaluation of a seal evaluation method, based on a hydrostatic pressure loading concept, for in-situ testing of seals in an operating mine. (PDF, 6213 KB, 2003-10)

This report analyzes mobile equipment fires for all U.S. surface and underground coal and metal/nonmetal mining categories by state and 2 year time periods during 1990-1999. (PDF, 1240 KB, 2004-01)

A U.S. Bureau of Mines investigation of longwall panel layouts to maximize coal recovery and minimize interactive problems in multiple-seam operations. (PDF, 992 KB, 1992)

This paper summarises the results of a research project whose goal was to provide the Australian coal industry with a rib support design methodology and software tool that could be utilised by suitably qualified colliery staff. (PDF, 286 KB, 2005)

Increasing longwall panel dimensions, particularly face width in gassy coalbeds, may result in unexpected increases in methane emissions. To investigate this problem, continuous longwall face emission monitoring studies were conducted at two adjacent mines operating in the Pocahontas No. 3 Coalbed, where longwall faces were to be extended from 229 to 305 m (750 to 1,000 ft). (PDF, 1919 KB, 1997)

Discusses several flyrock injury incidents at surface mines and construction sites and describes some injury mitigation techniques. (PDF, 133 KB, 2004)

The Bureau of Mines has developed an acoustic test for determining if a rock salt sample is from a "normal" nongassy salt face or from a gassy face where an outburst has the potential to occur. The acoustic test procedure and equipment are described, and raw test results and data analysis are shown. Results are also shown for several salt samples that were analyzed using a laser Raman microprobe. (PDF, 678 KB, 1990)

A case study is presented that relates statistical descriptions of joint sets to the distribution of local wedge failures along the crest of a catch bench at the Yellowstone Talc Mine. (PDF, 575 KB, 2004-05)

The results of a two-year research effort aimed at improving cormnunication systems in coal mines is reported, as well as a review of communication methods presently used in coal mines. Theoretical and-experimental results of a four pronged effort in the areas of (1) through-the-earth propagation, (2) paging system design, (3) improvement of wired telephone systems, and (4) carrier current systems are described. Auxiliary systems not included in the above are considered briefly. (PDF, 6143 KB, 1973-05)

The objective of this is paper is to review the current state of knowledge and practice in highwall mining. (PDF, 1182 KB, 2005)
                                            

This report analyzes mine fires for all U.S. underground and surface metal/nonmetal mining categories during 1990-2001 by state and six successive 2-year time periods. (PDF, 1793 KB, 2004-11)

This report analyzes mine fires for all U.S. underground and surface coal mining categories by state and 2-year time periods during 1990-1999. (PDF, 1611 KB, 2004-09)

NIOSH completed a major study to identify the location and likely severity of multiple seam interactions (undermining and overmining). More than 300 multiple seam case histories were assembled into the largest data base of multiple seam case histories ever collected. These data were analyzed with the multivariate statistical technique of logistic regression, LaM2D to estimate the multiple seam stresses, ALPS and ARMPS to determine pillar stability factors, and the CMRR to measure roof quality. The study resulted in the development of a computer program, called Analysis of Multiple Seam Stability (AMSS), which can help mine planners to evaluate each potential interaction and take steps to reduce the risk of ground control failure.  (PDF, 658 KB, 2007)

As underground stone mining expands to deeper cover situations, and more efficient mining methods are utilized, effective stone pillar design methods become more important. Seventy-two stone-mine pillar designs were examined or factors effecting stability and results are presented. (PDF, 1315 KB, 1999-12)

Some of the issues discussed in this article include highwall stability, reasons for early pull out of highwall miner holes, and geotechnical engineering and planning factors and operating practices to improve highwall stability and minimize the risk of a trapped highwall miner. (PDF, 335 KB, 2004-08)

A state-of-the-art, three-dimensional, full waveform, microseismic system was used to analyze the rock failure around a deep bump-prone longwall panel. Analysis of the recorded events is discussed. (PDF, 442 KB, 2001-08)

A statistical study was conducted of roof bolt performance at a number of mines throughout the U.S. Analysis of the results led to guidelines that can be used to make preliminary estimates of the required bolt length, capacity, and pattern to improve roof stability for more difficult conditions. (PDF, 140 KB, 2001-08)

A study was conducted to determine the causes of slope failure and highwall/spoilbank failure and included: a review of accident statistics; a review of mining laws pertaining to surface mining; a literature review; and mine visits. The study emphasized surface mines in West Virginia, Ohio and Pennsylvania. (PDF, 248 KB, 2000-08)

A seismic monitoring system located at NIOSH's Lake Lynn Experimental Mine has monitored experimental gas and dust based explosions and impact tests. The results suggest a large explosion that's not restricted can generate potentially the same magnitude as a small explosion that is restricted. (PDF, 959 KB, 2008)

This report describes serious injuries occurring to bulldozer operators working at U.S. coal, metal, and nonmetal mines. The period covered is 1988-97. (PDF, 345 KB, 2001-04)

To provide a better understanding of the mechanics of strata deformation, the authors have collected and reviewed measurements of convergence and stress in one western U.S. mine and have completed pseudo-three-dimensional, boundary-element modeling for two typical pillar-pulling plans. (PDF, 202 KB, 1998)

This U.S. Bureau of Mines publication is an analysis of 164 underground coal mine fire incidents occurring in the United States during the 15 years from 1978 through 1992. Fires were analyzed by year, State, coalbed thickness, mine size, mining method, ignition source, burning substance, location, equipment involved, detection method, time of day, time of year, number of injuries and fatalities, method of extinguishment, and evacuation measures taken. (PDF, 5674 KB, 1995)

A summary of past analyses that are relevant to electromagnetic location in mine rescue situations. The analytical results indicated that detection of a trapped miner equipped with a special transmitter is feasible in most situations. Location of the miner by surface measurements is also generally feasible within certain errors.  (PDF, 4916 KB, 1974-12-02)

Despite its potential importance, there is no widely accepted anchorage test for fully grouted roof bolts. Recent studies using short encapsulation pull tests are described. (PDF, 864 KB, 2002-08)

This report covers antenna deslgn, analysis, and development work suited for use with a wireless radio communication system operating at medium frequency. The work includes the test and evaluation of prototype vehicular antennas developed during the program. (PDF, 3045 KB, 1978)

A collaboration between the U.S. Bureau of Mines and Michigan Technological University to develop an apparatus for measuring diesel tailpipe emissions in underground mines. (PDF, 1483 KB, 1992)

Electromagnetic narrow-band signals were transmitted through the earth at 27 coal mines located throughout the United States. From those tests, apparent earth conductivity values were derived based upon a homogeneous half-space model of the earth. The derived conductivity values were found to be inversely proportional to the transmitted frequency and mine depth. A linear regression model relating the logarithm of the conductivity to the mine depth was formulated, and the results indicate that the mine depth can be an adequate predictor of the apparent earth conductivity above coal mines. Apparent earth conductivity was found to decrease with mine depths. (PDF, 977 KB, 1984)

This paper discusses the methods NIOSH used to identify noise sources on a roof bolting machine while drilling. (PDF, 3036 KB, 2007)
                                        

This paper describes Bureau of Mines research and development of a new and innovative mine lighting system based on fiber optics technology. The new lighting concept offers significant advantages over conventional systems in the areas of both safety and long-term maintenance costs. An overview of Bureau research into the problems and limitations of present-day mine lighting systems is also presented. (PDF, 616 KB, 1986)

This paper presents a discussion of the firefighting approach at the Excel No. 3 Mine and an analysis of the results of the application of gas-enhanced foam technology. (PDF, 1881 KB, 2005)

The objective of this study was to test the capability of ground penetrating radar to determine the extent of grout penetration into the mine roof strata in the 13-G room area of the NIOSH Safety Research Coal Mine. The study showed that GPR technology can be a useful tool for detecting changes in mine roof due to the injection of the grout. (PDF, 1051 KB, 2004-08)

This paper examines the effect of end conditions and load profiles on prop support performance and applies a new analysis methodology based on eccentric loading to determine a factor of safety for load capacity. Recommendations for installation practices that minimize eccentricity and therefore preserve capacity are also provided. (PDF, 304 KB, 2007)

An investigation of the hazards in and around ore passes in hard rock mines. Risk assessment methods, such as fault-tree analysis, have been employed to identify the most probable causes of ore-pass failures, define research priorities and analyze the factors that result in malfunctioning and unsafe ore passes. (PDF, 903 KB, 1997)

New developments in radio frequency identification (RFID) systems show promise for reducing the number of collisions between haulage equipment and pedestrian workers or other vehicles. This paper describes tests conducted on off-the-shelf RFID systems and the subsequent development of a custom RFID system that could be used for both surface and underground mining equipment. (PDF, 181 KB, 2001)

The Coal Mine Roof Rating (CMRR) has been widely accepted as a tool for geologic characterization and mine planning. The application of the CMRR to extended cuts (cuts greater that 6 m (20 ft) in length) is discussed. (PDF, 313 KB, 1999-04)

Several remote sensing technologies are being evaluated as tools to assess slope stability and monitor slopes for hazards. An interferometric radar device capable of detecting very small displacements on slopes has been assembled and tested. (PDF, 1440 KB, 2004)

This paper summarizes developments in the application of ground-based radar to slope stability monitoring and presents information on NIOSH-sponsored experiments recently completed. Field tests of a hyperspectral imager were conducted to assess its value for improving geologic maps of potentially unstable alteration zones on mine slopes (McHugh and others, 2001). Computerized monitoring methods using images from digital and video cameras are being assessed for application to mine slope surveillance. (PDF, 7065 KB, 2006-04)

The point estimation method is a computationally efficient approach for estimating the probability of sliding. This method expedites slope stability simulation routines used by NIOSH software to stochastically describe rock slope behavior and assist the engineer in designing catch benches for large rock slopes. Enhanced bench design translates into increased operational efficiency and safer working conditions in open pit mines and quarries. (PDF, 1713 KB, 2004)

This paper describes the use of four sources of data (injury records, the Nordic Standardized Musculoskeletal Questionnaire, supervisor interviews and management concerns) to prioritize jobs for ergonomic analysis. (PDF, 356 KB, 2001)

Rock drilling parameters including thrust, rotational speed, torque and velocity were examined to determine the ability to identify the strength of the rocks being drilled from the measured parameters. (PDF, 724 KB, 2000)

This paper introduces various warning signs of slope instability so operators are better able to recognize hazards. The most common slope monitoring equipment and practical methods of installation are discussed as well as the limitations of these systems. (PDF, 413 KB, 2001-08)

A methodology to assess the risk for a roof fall is proposed in a preliminary fashion based on engineering judgment acquired from extensive underground stone mine experience and examination of related literature. The proposed method uses an observational technique to identify the risk of roof falls in three categories. (PDF, 201 KB, 2006-03-27)

The Bureau of Mines investigated coal storage silos to determine how gassy coal must be for methane accumulations in a silo to become hazardous and where such accumulations are likely to occur. Methane concentrations were measured in the open space above the stored coal pile, in the pile, and in the reclaiming area. (PDF, 394 KB, 1981)

A research program was implemented to: 1) determine, characterize and to measure sound power levels radiated by a roof bolting machine during differing drilling configurations (thrust, rotational speed, penetration rate, etc.) and utilizing differing types of drilling methods in high compressive strength rock media (>20,000 psi); 2) distinguish and correlate the empirical data into one, statistically valid, equation, in which, provided the mining industry with a tool to predict overall sound power levels of a roof bolting machine given any type of drilling configuration and drilling method utilized in industry; 3) provide the mining industry with several approaches to predict or determine sound pressure levels in an underground coal mine utilizing laboratory test results from a roof bolting machine and 4) describe a method for determining an operators' noise dosage of a roof bolting machine utilizing predicted or determined sound pressure levels. (PDF, 3609 KB, 2006)

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)

This report describes an investigation by NIOSH researchers to quantify sound levels and to determine the amount of sound reduction provided by engineering noise controls installed in a talc processing plant. (PDF, 800 KB, 2008)

A summary is presented of existing leaky feeder communications systems currently in operation in North America. Background information pertaining to previous use of leaky feeder technology is discussed along with the survey methodology. Seven sites representing eight mines are included in the survey. (PDF, 556 KB, 1980)

This Bureau of Mines research study found gas emission rates from an advancing face, and flows and pressure of gas from an exploration drill hole were dependent upon the geology of salt encountered in a domal salt mine. This information suggests a greater methane emission hazard from the anomalous zone than from the associated normal salt. (PDF, 33349 KB, 1984)

Field studies have been conducted in a large number of coal mines throughout the U.S. to determine the effectiveness of electromagnetic techniques in locating men trapped underground following a mine disaster. Results indicate an expected 45% probability of detecting a miner's signal from a depth of 1,000 ft and a 90% probability at a depth of 500 ft. (PDF, 773 KB, 1980)

Two recent studies evaluated workers' dust exposures in automated pallet loading processes. The first study involved a Bureau-designed dust control system using a push-pull ventilation technique. The second study evaluated different commercial automated pallet-loading systems. Results from a ground silica evaluation site indicated respirable dust samples taken were below the threshold limit value as established by the Mine Safety and Health Adminstration. (HTML, KB, 1990)

A U.S. Bureau of Mines study on the potential availability of copper from 204 mines and deposits in market economy countries. (PDF, 2199 KB, 1992)
                          

This article discusses research results of studies that shed light on possible mechanisms through which low back injuries may occur and how this knowledge can be leveraged to reduce the risk of low back pain. (PDF, 597 KB, 2007)

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)

Although MSHA still mandates instruction in barricading, greater emphasis is now placed on teaching miners to use SCSRs proficiently and to be knowledgeable about their escape routes. Only recently has at least one mine operator begun to revisit barricading as an alternative to escape. (PDF, 1020 KB, 1997-11)

This paper describes research designed to quantify the behavior of a particular size abutment pillar prone to burst or bump (local terminology). This information reflects the overriding influence of the local geologic characteristics on bursts, provides the field measurements needed to verify concurrent modelling studies, and suggests some basic mechanisms associated with coal pillar bursts. (PDF, 516 KB, 1990-08)

Gas occurs in coalbeds in an adsorbed and a free gas state. Adsorbed gas is stored in the micropore structure and its transport is governed by Fick's law. The free gas occurs in the fracture system and flows according to Darcy's law. These two modes of mass transport are interdependent. Production decline curves of coal-gas wells are of the constant percentage decline type and, thus, show no indications of flow characteristics peculiar to coal-gas reservoirs. The effectiveness of surface boreholes as a degasification scheme depends upon both good fracture permeability and a high fracture density. Conventional methods of reservoir engineering analysis are not applicable to coalbeds. (PDF, 1022 KB, 1969)

In this study, 10-lb charges of blasting agent confined in either thin-wall 4-in-diam galvanized pipe or 4-in schedule 80 stainless steel pipe were detonated in a closed chamber. detonation gases were analyzed for nitrogen dioxide, nitric oxide (NO), ammonia, hydrogen, carbon monoxide, carbon dioxide, nitrogen, oxygen, and methane. Data were evaluated to determine the kinetics of the oxidation of NO to nitrogen dioxide. The information on NO oxidation kinetics provided will prove useful in efforts to model the behavior of NO and nitrogen dioxide in clouds of detonation products near blasting operations. (PDF, 158 KB, 2006-01)

This report presents results of a U.S. Bureau of Mines study of longwall gob material. The objective of this work was to determine material stiffness properties of the gob for use in numerical models or rock mass response to longwall mining. (PDF, 5208 KB, 1993)

A scientific study of human behavior during an escape from a fire in an effort to understand and derive benefits for design, engineering and safety efforts. (PDF, 1291 KB, 2000-05)

The U.S. Bureau of Mines established a wire rope research laboratory to examine the factors that affect the life of wire rope. The tests indicated that once a wire rope nears the end of its service life, both deterioration and the consequent loss of rope strength begin to increase at an accelerated rate. (PDF, 2451 KB, 1992)

Injury data are presented that show a dramatic reduction in roof skin injuries when screening is used. Five case studies in which roof screen was used are presented along with the associated costs of materials, impact on bolting advance rates, and potential ergonomic risks. The effects of roof screening on skin control and safety are also included. Finally, this paper provides information about best practices and features of roof bolting machines that affect production and safety. (PDF, 141 KB, 2003)

Based on their findings, the task group offered several best practice recommendations that a mine may want to follow to implement a successful ceramic DPM filter program. The best practices identified are believed to be key elements for implementation of a successful effort using ceramic filters.  (PDF, 1235 KB, 2007)

This paper presents an overview of the most significant ground control hazards facing today's mineworkers, as well as best practices to reduce these risks. (PDF, 1971 KB, 2000)

Twelve subjects participated in an investigation of the biomechanical stresses of asymmetric lifting in stooped and kneeling postures. Three factors were manipulated in this study: posture (stooped or kneeling), height of lift (35 or 70 cm), and weight of lift (15, 20 or 25 kg). (PDF, 258 KB, 1997)

This paper describes the development of a multi-body biomechanical model that can be used to assess the risk of low back disorders due to occupational exposure to jarring and jolting from operation of heavy mobile equipment (e.g., trucks, haulers, graders, tractors, etc.) (PDF, 246 KB, 2003-08)

This project investigates the behavior of blast waves from the detonation of high explosives in an underground mine. (PDF, 747 KB, 1995)
                                   

This paper describes several fatal injury case studies, analyzes causative factors, and emphasizes preventive measures. (PDF, 380 KB, 2004-01)
                                

This paper examines the factors related to injuries due to inadequate blasting shelters and blast area security, and identifies mitigation techniques. (PDF, 120 KB, 2005)

A detailed description of blasting-related carbon monoxide migration from a construction site into nearby residential homes. (PDF, 1780 KB, 2004)
                           

Air quantity-pressure and methane concentration surveys were conducted in accessible portions of an area being pillared in a Pittsburgh coalbed mine in West Virginia. These included two mined-out and three active butt headings and a bleeder system. The particular mine workings were started in virgin coal directly from a set of main headings; the main reason for the study was the difficulty usually encountered in adequately bleeding the gobs under such conditions. (PDF, 597 KB, 1973)

The U.S. Bureau of Mines conducted a worldwide literature review of bleederless ventilation practices to evaluate their use as a spontaneous combustion control measure in U.S. coal mines. This report describes the types of ventilation systems used throughout the world and the spontaneous combustion risks associated with these systems. (PDF, 3168 KB, 1994)

The San Juan Mine and the National Institute for Occupational Safety and Health conducted a study to measure how development mining affected bolt loads. (PDF, 600 KB, 2004)

This paper compares the fatigue failure responses of older versus younger lumbar spine cadaver motion segment specimens. (PDF, 75 KB, 2005)
                               

This report describes the feasibility test of an electromagnetic method for locating boreholes, with or without casing, that have been drilled in conjunction with mining operations but without precisely known locations with respect to the tunnel. The demonstration tests were done at ranges on the order of 100 to 200 feet, but the method is capable of working at much greater distances. (PDF, 4827 KB, 1978)

Researchers with NIOSH studied the electrical equipment ignition sources for the Brookwood and other disasters to develop recommendations for preventing similar disasters.  (PDF, 373 KB, 2007)

The purpose of this project was to enhance the Bureau of Mine's Cableless Electronic Survey System use to aid in the drilling of long boreholes in coal as part of the methane drainage program. The system that was ultimately developed was field tested and demonstrated in actual in-mine drilling activities. The significance of the system, compared with previous drill survey systems, is that it surveys without having to be inserted and removed for each survey point. The system is so designed that it can withstand the shock and vibration experienced by the drill string during drilling. Thus increased productivity is possible and drill operators can determine drill bit positioning in a near real-time environment. (PDF, 6464 KB, 1981)

This paper presents data and theorem to calculate the risk of experiencing undesirable lightning related events while blasting or while engaged in other lightning sensitive activities. The paper provides an overview of lightning hazards in blasting operations and a brief history of lightning related blasting accidents. (PDF, 1001 KB, 1998)

The Bureau of Mines developed a computerized method to calculate vertical stress exerted on surfaces at depth that includes the effect or topography. The limitation of the method is that stresses cannot be accurately determined near an outcrop. (PDF, 4167 KB, 1992)

Roof and floor contact pressure provided by the interaction of a shield with the surrounding strata are examined. Controlled forces were applied to an 800-ton two-leg shield using a mine roof simulator. (PDF, 4632 KB, 1992)

NIOSH, RAG Pennsylvania and Strata Control Technologies of Australia collaborated in an intensive study of ground behavior, reinforcement performance, and stress redistribution at the Emerald Mine in Southwestern Pennsylvania. The study site was a longwall tailgate subjected to a severe horizontal stress concentration. A computer simulation of the field site was conducted using FLAC-2D. Comparison between actual field measurements and the simulation showed that the model was able to capture the most significant aspects of the roof and support system behavior. The model also showed that supplementing the normal roof bolt support pattern with cable bolts would allow the entry to survive a further 20-25% increase in the applied horizontal stress. (PDF, 1254 KB, 2007)

Instrumented cable bolts were used in conjunction with existing ground control to monitor rock mass loads at various field sites. Axial and shear loads were determined by strain gauges as these loads were transferred to instrumented cable bolts. Cable bolt performance, quality of grout, and installation techniques were also assessed. By monitoring load on and discplacement of the rock mass, more effective ground support can be selected and installed, which will lead to safer working conditions for miners. (PDF, 3413 KB, 2001-07)

This paper presents the results of a case study conducted in a two-entry gateroad in a coal mine where excessive roof deformation and bolt loading resulted in failure of many roof supports. (PDF, 803 KB, 1998)

An analysis of roof bolting tasks was conducted at a mine to identify early warning signs of cumulative trauma. Health and safety risk factors were identified and recommendations to reduce cumulative trauma exposure were provided. (PDF, 426 KB, 2001)

Based on a comprehensive data base of mining accidents, a computerized catastrophe model has been developed by the Bureau of Mines which systematically links individual psychological, group behavioral, and mine environmental variables with other accident causing factors. It answers several longstanding questions about why some normally safe behaving persons may spontaneously engage in unsafe acts that have high risks of serious injury. (PDF, 1969 KB, 1988)

This report presents a Bureau of Mines study to identify the causes of self-heating events beneath the floor of a deep underground coal mine. The combined results led to the conclusion that pyrite oxidation was the prime cause of the heatings. (PDF, 4994 KB, 1992)

A Computational Fluid Dynamics (CFD) program was used to model buoyancy induced Product-Of-Combustion (POC) spread from experimental fires in the National Institute for Occupational Safety and Health (NIOSH), Pittsburgh Research Laboratory (PRL), safety research coal mine. (PDF, 384 KB, 1999)

A computational fluid dynamics (CFD) program was applied to fire spread along combustibles in a ventilated mine entry. The rate of flame spread was evaluated for the ribs and roof of a coal mine entry, timber sets, and a conveyor belt. The CFD program predicted a flame spread rate of 0.0145 m/sec for an actual coal mine fire in which the estimated flame spread rate was 0.0086 m/sec. This overestimated flame spread rate was a possible consequence of the presence of inert materials in the mine entrys roof and ribs. (PDF, 178 KB, 2006)

In the present study, a computational fluid dynamics (CFD) program is used as a design tool to model floor-level fires in a ventilated tunnel. (PDF, 397 KB, 2001)

This paper presents some findings obtained from interviews with coal miners about why supervisors sometimes fail to enforce an important mine safety rule. It also contains a few suggestions addressing what could be done to help supervisors perform this job function more effectively. (PDF, 107 KB, 1999)

Organizational practices have changed dramatically in recent years. To compete more effectively, many companies have restructured themselves and downsized their workforces, increased their reliance on nontraditional employment practices that depend on temporary workers and contractor-supplied labor, and adopted more flexible and lean production technologies. These revolutionary changes in the organization of work have far outpaced our understanding of their implications for work life quality and safety and health on the job. (PDF, 487 KB, 2002)

This study used microseismic emissions to help identify three local rock failure processes. It was also shown that analysis of microseismic emissions can aid in assessing the degree of instability associated with these local rock failure processes. (PDF, 312 KB, 2005)

Ultrasonic ranging sensors are inexpensive, have no moving parts, have no lenses to clean, are normally small and unobtrusive, and can measure distances through moderate amounts of dust, smoke, and humidity, so they are well suited to underground mines. In the work reported here, conducted by the U.S. Bureau of Mines, researchers tesed ultrasonic ranging sensors for their ability to define rib line features for computer-aided navigation of underground mine mobile equipment. (PDF, 3008 KB, 1993)

Investigation of the geologic and mining factors influencing the migration of longwall gob gas with a goal to optimize methane drainage strategies to reduce the volume of gob gas that reaches the underground workplace. (PDF, 175 KB, 1999)

A system that ties acceleration data with Global Positioning System (GPS) data was developed, assembled and tested to track the frequency and causes of jolting and jarring of heavy equipment operators. Such information could provide feedback to truck operators about how their driving affects jolting and jarring and identify the location of haulage road problems. (PDF, 568 KB, 1999)

The objective of this paper is to identify and characterize nanometer and ultrafine aerosols emitted by diesel engines in the underground environment and evaluate the effects of selected contemporary control technologies on physical properties, chemical composition, and in-vitro toxicology of diesel aerosols. (PDF, 342 KB, 2007)

This article introduces a one-page checklist for evaluating cab design of construction equipment. The cab design evaluation checklist was developed, pilot-tested, and used to measure several characteristics of cab design. A case study is presented in which overall cab design scores were calculated for each type of equipment. (PDF, 45 KB, 2003)

Report on a NIOSH study to identify factors that may contribute to nitrogen oxides (NOx) production associated with non-ideal detonation of blasting agents. (PDF, 1147 KB, 2002-02)

The Bureau of Mines investigated the physical characteristics of and roof instability problems associated with clay veins. This was accomplished by observing and mapping clay veins in surface and underground mines. The occurrence and origins of clay veins were also investigated to determine predictive capabilities. (PDF, 3464 KB, 1987)

This report addresses issues involved in using a limited number of training apparatus to give hands-on self- contained self-rescuer (SCSR) training to a succession of miners, and provides guidance regarding methods for minimizing the spread of infectious diseases. (PDF, 928 KB, 1989)

The natural vertical fracture system in bituminous coalbeds is called cleat. Cleat orientation commonly controls the direction of mining with major development paralleling the face cleat. Previous researchers have categorized the origin of cleat as endogenetic, relating the origin of cleat to compaction and coalification, and exogenetic, relating the origin of cleat to tectonic forces. In the coalbeds studied for this report it was found that tectonic forces were the controlling factor of cleat formation. Cleat orientation in other bituminous coalbeds in Virginia, Utah, Oklahoma, and central Pennsylvania showed a relationship to local structure. Directional permeability of coal is directly related to cleat. Holes drilled perpendicular to the face cleat yield from 2.5 to 10 times the amount of gas released as compared with holes drilled perpendicular to the butt cleat. (PDF, 1031 KB, 1974)

Dirty worker clothing has been identified as a source of exposure to respirable dust. If this respirable dust contains silica it may cause the inhaler to deve