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Showing 4301 - 4320 of 82972 results
  • A Summary of Respirable Coal Mine Crystalline Silica Dust Research Accomplished Through the Miner Act Under the NIOSH Office of Mine Safety and Health Research
    A Summary of Respirable Coal Mine Crystalline Silica Dust Research Accomplished Through the Miner Act Under the NIOSH Office of Mine Safety and Health Research
    Luxbacher GW ;
    Reed, William R.
    2022/02/27 | Mining Publications
    As directed by the MINER act of 2006, the NIOSH Office of Mine Health & Safety Research (OMSHR) has annually awarded contracts to enhance mine safety and health. OMSHR has a history of research that focuses on both respirable coal mine dust and respirable crystalline silica (or quartz) dust, and contracts have been awarded since 2010 in support of ...
    Public Domain
  • A Laboratory Investigation of Underside Shield Sprays with a ShearerClearer Water Spray System to Improve Dust Control on Longwall Faces
    A Laboratory Investigation of Underside Shield Sprays with a Shearer-Clearer Water Spray System to Improve Dust Control on Longwall Faces
    Beck, Timothy W. ;
    Driscoll JS
    2022/02/27 | Mining Publications
    Previous testing was performed by researchers at the National Institute for Occupational Safety and Health (NIOSH) to improve longwall dust control using underside shield sprays with a longwall directional spray system. This testing provided encouraging results toward respirable dust exposure reductions for longwall personnel, achieving as high as ...
    Public Domain
  • Effect of Binder Content on the Ductility of Cemented Hydraulic Backfill
    Effect of Binder Content on the Ductility of Cemented Hydraulic Backfill
    Armatys M ;
    Bourgeois JP
    2022/02/27 | Mining Publications
    The Spokane Mining Research Division (SMRD) of the National Institute for Occupational Safety and Health (NIOSH) has partnered with a narrow vein, hard rock underground mine to research the effects of the binder content on the elasticity and post-peak ductility of cemented hydraulic backfill (CHB). This is part of a larger study to enhance the long ...
    Public Domain
  • Utilization of Statistical Analysis to Identify Influential Slope Parameters Associated with Rockfall at Open Pit Mines
    Utilization of Statistical Analysis to Identify Influential Slope Parameters Associated with Rockfall at Open Pit Mines
    Armstrong J ;
    Bourgeois J
    2022/02/27 | Mining Publications
    The application of statistical analysis software programs has proven useful for investigation of rockfall runout distance along a designed slope. Rockfall modeling programs are continually being upgraded with more sophisticated analysis tools, such as the use of the rigid body versus lump mass models. Engineers at mine sites utilizing the software ...
    Public Domain
  • Rockmass Permeability Induced by Longwall Mining Under Deep Cover Potential Gas Inflow from a Sheared Gas Well
    Rockmass Permeability Induced by Longwall Mining Under Deep Cover: Potential Gas Inflow from a Sheared Gas Well
    Ajayi KM ;
    Esterhuizen, Gabriel S.
    2022/02/27 | Mining Publications
    The stability of shale gas wells drilled through current and future coal reserves can be compromised by ground deformations due to nearby longwall mining. Depending on the longwall-induced rockmass permeability, the high-pressure explosive gas from the damaged well may reach mine workings and overwhelm the mine ventilation systems. This study uses ...
    Public Domain
  • Detection and characterization of nanoparticles in respirable coal mine dust
    Detection and characterization of nanoparticles in respirable coal mine dust.
    Akinseye T ;
    Assemi S
    2022/02/27 | National Institute for Occupational Safety and Health (NIOSH)
    Respirable coal mine dust (RCMD) is a complex mixture of carbonaceous and mineral particles with a variation in size and shape. Accumulation of RCMD in the lungs of underground coal miners results in severe respiratory damage and ultimately progressive pneumoconiosis known as the black lung disease. The occurrence of the black lung disease dropped ...
  • Use of Cognitive Task Analysis to Inform Future Research and Identify Solutions for Haul Truck Safety
    Use of Cognitive Task Analysis to Inform Future Research and Identify Solutions for Haul Truck Safety
    Bellanca, Jennica L. ;
    Benbourenane I
    2022/02/27 | Mining Publications
    Each year, haul truck accidents account for a large portion of mining injuries and fatalities. To better understand why these accidents continue to occur, researchers from the National Institute for Occupational Safety and Health (NIOSH) utilized a cognitive task analysis methodology to identify the user requirements of surface haul truck operators ...
    Public Domain
  • Optimization of Auxiliary Fan Placement for LargeOpening Underground Stone Mines
    Optimization of Auxiliary Fan Placement for Large-Opening Underground Stone Mines
    Gangrade V ;
    Watkins E
    2022/02/27 | Mining Publications
    Large-opening stone mines often rely on natural ventilation and a network of auxiliary fans to produce adequate ventilation conditions in the mine instead of main mine fans, which are commonly utilized in coal mines. Large air volumes in underground stone mines, poor ventilation practices, and low operating budgets for mine ventilation potentially ...
    Public Domain
  • A Direct Derivative Method to Calculate Resistance Sensitivity for Mine Ventilation Networks
    A Direct Derivative Method to Calculate Resistance Sensitivity for Mine Ventilation Networks
    Bahrami D ;
    Zhou L
    2022/02/27 | Mining Publications
    A reliable and stable ventilation system is essential to the safe operation of underground mines. The stability of a mine ventilation system becomes extremely critical while responding to a fire incident since an unstable ventilation system will pose a risk of airflow reversal. The reversed airflow could bring the fire contaminants such as toxic ga ...
    Public Domain
  • Stress measurement and monitoring in anisotropic rock
    Stress measurement and monitoring in anisotropic rock.
    Pariseau, W. G.
    2022/02/27 | National Institute for Occupational Safety and Health (NIOSH)
    Reliable stress measurement using hollow inclusion gauges and monitoring stress change using borehole stress meters and borehole deformation gauges in anisotropic rock remains a challenge for the rock mechanics community. In this regard, the complex variable method advanced in 1983 for deducing stress in anisotropic rock is flawed and software is p ...
  • LithiumIon Battery Thermal Runaway in a MethaneAir Environment
    Lithium-Ion Battery Thermal Runaway in a Methane-Air Environment
    Brown C ;
    Dubaniewicz, Thomas H. Jr.
    2022/02/27 | Mining Publications
    As lithium-ion batteries (LIBs) become more prevalent in the mining industry, new hazards of battery fire and explosion are emerging. Efforts must be taken to ensure that workers are safe from these new hazards, such as batteries undergoing thermal runaway in underground areas that may have explosive methane-air mixtures. Researchers at the Nationa ...
    Public Domain
  • Statistical Analysis of Diesel Particulate Matter and Silica for Underground Stone Mines
    Statistical Analysis of Diesel Particulate Matter and Silica for Underground Stone Mines
    Gangrade V ;
    Harris, Marcia L.
    2022/02/27 | Mining Publications
    Underground stone mine ventilation is characterized by large openings with low resistances. These mines primarily face three challenges: moving adequate volumes of air, controlling and directing the airflow, and planning ventilation systems that work well with production requirements. Given these challenges, this paper examines the data collected b ...
    Public Domain
  • Analysis of US Surface Mining HaulTruckRelated Fatalities
    Analysis of U.S. Surface Mining Haul-Truck-Related Fatalities
    Bickson J ;
    DeGennaro C
    2022/02/27 | Mining Publications
    Powered haulage and haul truck-related fatal accidents are among the most frequent at surface mines. Industry organizations developed guidance on accident scenarios to address haul truck and mobile equipment collision-related accidents. However, there is a need to investigate accident data to prioritize these scenarios and identify factors relevant ...
    Public Domain
  • Identifying the Location and Size of an Underground Mine Fire with Simulated Ventilation Data and Random Forest Model preprint
    Identifying the Location and Size of an Underground Mine Fire with Simulated Ventilation Data and Random Forest Model [preprint]
    Bahrami D ;
    Xue Y
    2022/02/27 | Mining Publications
    Underground mine fires are a threat to the safety and health of mine workers. The timely determination of the location and size of an underground fire is of great importance in developing firefighting strategies and reducing the risk of any injuries. Machine learning was used in this paper to develop a predictive model for fire location and fire si ...
    Public Domain
  • An Overview of Methods and Parameters to Evaluate Detection Performance and Validation of Collision Warning and Avoidance Systems
    An Overview of Methods and Parameters to Evaluate Detection Performance and Validation of Collision Warning and Avoidance Systems
    Bickson J ;
    DeGennaro CR
    2022/02/27 | Mining Publications
    Between 2005 and 2021, a NIOSH internal review showed that haul trucks were involved in 54 incidents at surface mines in the United States. Haul truck collision warning and avoidance systems (CXS) can assist in preventing accidents at surface mines. CXS use technologies to detect people or objects and alarm to alert haul truck operators. Robust tes ...
    Public Domain
  • Gas Source Discrimination Methods to Identify the Occurrence of a Hypothetical Unconventional Gas Well Breach into a Nearby Longwall Mine
    Gas Source Discrimination Methods to Identify the Occurrence of a Hypothetical, Unconventional Gas Well Breach into a Nearby Longwall Mine
    Ajayi K ;
    Gangrade V
    2022/02/27 | Mining Publications
    The National Institute for Occupational Safety and Health (NIOSH) has been conducting research related to unconventional gas wells positioned in abutment pillars associated with active longwall mining in Southwestern PA. The Ventilation and Explosion Prevention Team at NIOSH is working toward predicting and characterizing a hypothetical casing brea ...
    Public Domain
  • Hot Surface Ignition of Liquid Fuels Under Ventilation
    Hot Surface Ignition of Liquid Fuels Under Ventilation
    Bahrami D ;
    Soles J
    2022/02/27 | Mining Publications
    Mine equipment fires remain as one of the most concerning safety issues in the mining industry, and most equipment fires were caused by hot surface ignitions. Detailed experimental investigations were conducted at the NIOSH Pittsburgh Mining Research Division on hot surface ignition of liquid fuels under ventilation in a mining environment. Three t ...
    Public Domain
  • Numerical Analysis of the Effect of Lamination Properties on Roof Failure in Coal Mines Using Coupled FDMDEM
    Numerical Analysis of the Effect of Lamination Properties on Roof Failure in Coal Mines Using Coupled FDM-DEM
    Mishra B ;
    Shi Q
    2022/02/27 | National Institute for Occupational Safety and Health (NIOSH)
    Numerical simulations have been used to investigate roof fall in the past decades. Comparing to the continuum based methods, the discrete element method has been well recognized for its excellent performance in simulating large strain problems and fracturing processes in the rock mass. However, the discrete element method has its limitations. When ...
  • Simulating the Impact of a Shale Gas Well Breach on Longwall Mine Ventilation Utilizing a Scaled Physical Model
    Simulating the Impact of a Shale Gas Well Breach on Longwall Mine Ventilation Utilizing a Scaled Physical Model
    Addis J ;
    Gangrade V
    2022/02/27 | Mining Publications
    The recent shale gas revolution in the United States has led to the drilling of hundreds of unconventional shale gas wells in active and future coal reserves in traditional coal-mining regions of Pennsylvania, West Virginia, and Ohio. This paper summarizes the impact of a shale gas well breach on the mine ventilation system of an operating longwall ...
    Public Domain
  • Survey of Electromagnetic Emissions in Underground Coal Mines
    Survey of Electromagnetic Emissions in Underground Coal Mines
    Damiano, Nicholas W. ;
    Jacksha R
    2022/02/27 | Mining Publications
    Modern electronic devices and systems used to enhance miner safety and health are becoming commonplace in underground coal mines. The ability for these devices and systems to function properly in the presence of electromagnetic emissions from other electronic and electrical devices and systems is not entirely understood. To investigate potential el ...
    Public Domain
4301 - 4320 / 82972