Mining Project: Advanced Strategies for Controlling Exposures to Diesel Aerosols
To develop and implement workplace solutions to reduce miners’ overexposure to hazardous airborne contaminants emitted from diesel-powered equipment.
Diesel-powered equipment is extensively used in the underground mining industry in the United States. Over 5,000 diesel engines provide power to various equipment in 185 underground coal mines, and approximately 7,700 diesel-powered units are deployed in 177 underground metal and nonmetal mines. As a result, approximately 15,000 underground coal miners and 13,000 underground metal/nonmetal miners in the U.S. are exposed to aerosols and gases emitted by diesel engines, and exposure of underground miners to diesel aerosols is the highest among workers in all occupations. Exposure to diesel exhaust is also linked to various adverse health outcomes. Long-term exposure to combustion-related fine particulate pollution is perceived as an important risk factor for cardiovascular and lung cancer mortality, and in 2012, the International Agency for Research on Cancer (IARC) categorized diesel engine exhaust as a carcinogen to humans (Group 1).
Extensive efforts on the part of industry and government have resulted in dramatic reductions in the average exposure levels of underground miners to diesel particulate matter (DPM). However, additional efforts are needed to further reduce exposures that, according to the compliance data gathered by the Mine Safety and Health Administration (MSHA), frequently exceed the current MSHA permissible exposure limit (PEL) of 160 µg/m³. Engineering and other solutions are particularly needed to address issues specific to a variety of duties and tasks performed in challenging underground mining environments.
Through the development, evaluation, and demonstration of an array of underground-mining-viable advanced control strategies and technologies, this project research will provide the industry with a number of necessary tools to significantly reduce miners’ exposures to diesel aerosols and gases.
The five research aims of this project are as follows:
- To develop and evaluate technologies and strategies to prevent overexposures to DPM of critically affected occupations in underground metal and nonmetal mining operations.
- To evaluate, in both the laboratory and the field, novel and emerging advanced engine technologies for heavy-duty (HD) and light-duty (LD) underground mining applications.
- To develop and evaluate, in both the laboratory and the field, advanced disposable filter elements for use in filtration systems for permissible diesel-powered equipment.
- To develop and evaluate environmental enclosures and filtration systems for mobile underground mining equipment as a control strategy for diesel aerosols.
- To develop and evaluate canopy air curtains for mobile underground mining equipment as a control strategy for diesel aerosols.
The potential outcomes of this project research are to produce several peer-reviewed, conference, and other publications on the topics related to the research aims outlined above. Also, presentations are planned to be given at various national and international conferences such as the Mining Diesel Emissions Council Conference and the ETH Conference on Combustion-Generated Nanoparticles. Pending availability of funding, one-day diesel workshops and short courses are planned for the North American Mine Ventilation Symposium and the Australian Mine Ventilation Conference.
The adoption and implementation of control technologies and strategies evaluated in this project should result in substantial reductions in average exposure levels and the number of overexposures of underground workers in selected metal and nonmetal mines, and in an increase in the use of advancement engines and exhaust aftertreatment devices and environmental enclosures in the U.S. coal, metal, and nonmetal mining industries. The analysis of MSHA compliance data for the years that would follow implementation of NIOSH-developed intervention would be used to assess the impact of these interventions.
Bugarski AD, Hummer JA, Vanderslice S, Barone T . Retrofitting and repowering as control strategies for the curtailment of exposure of underground miners to diesel aerosols. J Min Met Explor 37(2):791-802.
Bugarski AD, Hummer JA, Vanderslice S, Mischler S . Contribution of various types and categories of diesel-powered vehicles to aerosols in an underground mine. J Occup Environ Hyg 17:121-134.
Bugarski AD, Hummer JA, Vanderslice SE . Effects of FAME biodiesel and HVORD on emissions from an older technology diesel engine. Min Eng 69(12):43-49.
Bugarski AD, Hummer JA, Miller A, Patts LD, Cauda AG, Stachulak JS . Emissions from a diesel engine using Fe-based fuel additives and sintered metal filtration system. Ann Occup Hyg 60(2):252-62.
Yanamala N, Hatfield MK, Farcas MT, Schwegler-Berry D, Hummer JA, Shurin MR, Birch ME, Gutkin DW, Kisin E, Kagan VE, Bugarski AD, Shvedova AA . Biodiesel versus diesel exposure: Enhanced pulmonary inflammation, oxidative stress, and differential morphological changes in the mouse lung. Tox Appl Pharm 272:373-383.