Coal mine dust

Coal-Mine Dusting. A steady market for pulverized limestone is ia dusting coal mines with a noncombustible mineral dust as a federally mandated mine safety requirement. Of aU mineral dusts, limestone is by far the most commonly used (60—75% 0.074 mm (200 mesh)). Consumption ia 1991 was... 

Silica, amorphous Silica, crystalline Silica in coal mine dust Silicon... 

In addition to the aforementioned dusts and fibers, coal mine dusts may also stimulate oxygen radical production [199], In this case hydroxyl radical production and lipid peroxidation also correlated well with the content of available surface iron. It has been proposed that free radical-mediated processes can be a casual cause of coal workers pneumoconiosis due to exposure to coal dusts. 

Seixas, N. S.. Robins, T. G., Attfield, M. D. Moulton, L. K 1992. Exposure-response relationships for coal-mine dust and obstructive lung-disease following enactment of the Federal Coal-Mine Health and Safety Act of 1969. American Journal of Industrial Medicine, 21, 715-734. 

Respirable Dust—with the objective of providing improvements for protecting miners from exposure to respirable coal mine dust. Study areas have included (a) dust formation fb) dust control, and (c) dust measurement. Tests have included the infusion of water into coal beds for control of respirable dust the use of water-based, high-expansion foaming systems in conjunction with continuous mining machines, to reduce dust at the face the use of roam systems for dust suppression on conveyors and transfer points and the use of prototype dust meters. See also Pneumokonioses. 

Scanning electron microscopy with an energy-dispersive x-ray system accessory has been used to identify the composition and nature of minerals in coals and to determine the associations of minerals with each other. Examinations can be made on samples resulting from ashing techniques or whole coal. With this technique it is possible to identify the elemental components and deduce the mineral types present in coal samples. Computerized systems to evaluate scanning electron microscopy images have been developed and are useful in characterizing the minerals in coal mine dusts and in coal. 

Respirable coal mine dust samples from three different US mines were classified into four fractions using a Bahco classifier [34]. Shape factors were determined as ratios of the following mean diameters. From microscopy ... 

Castranova V. (2000) From coal mine dust to quartz mechanisms of pulmonary pathogenicity. Inhalat. Toxicol. 12, 7-14. 

Rock Dust [Georgia Marble] Ground calcium carbonate filler for coal mine dusting. 

The NIOSH REL for coal mine dust was added to the coal dust entry. 

See Appendix C (Coal Dust and Coal Mine Dust)... 

Note The Mine Safety and Health Administration (MSHA) PEL for respirable coal mine dust with < 5% silica is 2.0 mg/m or (10 mg/m ) / (% respirable quartz + 2) for coal dust with > 5% silica.]... 

The NIOSH REL (10-hour TWA) for respirable coal mine dust is 1 mg/m, measured using a eoal mine personal sampler unit (CPSU) as defined in 30 CFR 74.2. The REL is equivalent to 0.9 mg/m measured according to the ISO/CEN/ACGIH (International Standards Organization/ Comite Europeen de Normalisation/American Conference of Governmental Industrial Hygienists) definition of respirable dust. The REL applies to respirable coal mine dust and respirable eoal dust in occupations other than mining. NIOSH recommends a separate REL for erystalline siliea. See NIOSH publication 95-106 (Criteria for a Recommended Standard -Occupational Exposure to Respirable Coal Mine Dust) for more detailed information. 

US General Accounting Office. 1975. Improvements Still Needed in Coal Mine Dust-San ling Program. GPO Washington. 

Fu G, et al. 2002. Coal mine dust control 20-25. Beijing China University of Mining and Technology Fhess. (in Chinese). 

An LCA-based health damage evaluation method for coal mine dust... 

Jin, L.Z. 1993. Control Coal Mine Dust. Beijing Coal Industry Press. 

Respirable dust sample A sample collected with an approved coal mine dust sampler unit attached to a miner, or so positioned as to measure the concentration of respirable dust to which the miner is exposed, and operated continuously over an entire work shift of such miner. 

The American Industrial Hygiene Association (AIHA) provided comments to the Mine Safety and Health Administration (MSHA) on its proposed rule regarding miners exposure to respirable coal mine dust (published in the Federal Register on October 19,2010). 

While AIHA supports lowering existing concentration limits for respirable coal mine dust, the organization objects to MSHA s bid to expand the requirements of certified persons who perform dust sampling and who maintain and calibrate sampling equipment, said AIHA President Michael T. Brandt, DrPH, CIH, PMP, in a written statement. Linder the proposal, individuals must be certified by passing an MSHA examination to demonstrate competency in respirable coal mine dust after completing an MSHA course of instruction. 

Brandt said that requiring CIHs to get additional instruction and certification would incur unnecessary costs and urged MSHA to recognize certified industrial hygienists as having met the requirements to conduct air sampling of respirable coal mine dust. 

The research authority vested in NIOSH has helped to fuel advances by NIOSH and its partners against a broad range of workplace hazards, including lead, asbestos, dioxin, coal mine dust, traumatic injuries, workplace violence, latex allergy, and occupational lung disease associated with butter flavorings. 

While Ray et al. (1951) did not find any inhibitory effect on the action of quartz by anthracite and coal mine dusts mixed with quartz when introduced by intratracheal instillation in the lungs of rats, Rehn et al. (1995) raised the question whether the formation of reactive oxygen species by macrophages engulfing coal mine dust containing free silica could be depressed by the coal part. 

In rats, illite and muscovite, but not kaolin produced lesions of alveolar proteinosis (Martin et al. 1977). Reisner et al. (1982) and Rosmanith et al. (1982) emphasised that the relation between the ka-olinite content of the lymph nodes and that of the lungs six months after an intratracheal injection of different West German coal mine dusts showed an exponential regression function by the method of least squares. 

Laser-microprobc mass spectrometry has an unusually high sensitivity (down to 10 g), is applicable to both inorganic and organic (including biological) samples, has a spatial resolution of about I pm, and produces data at a rapid rate. Some typical applications of laser-microprobe mass spectrometry include determination of Na/K concentration ratios in frog nerve fiber, determination of the calcium distribution in retinas, classification of asbestos and coal mine dusts, determination of fluorine distributions in dental hard tissue, analysis of amino acids, and study of polymer surfaces. ... 

Coal mine dust personal sampler units Gas detector tube units Respiratory protection devices Obsolete respirators Somid level meter sets... 

In coal mines, dust samples are collected by both coal mine operators and the Mine Safety and Health Administration (MSHA) using a size-selective sampling device (cyclone) that separates out dust in a way that reflects the efficiency of deposition in the gas-exchange region of the lungs. This so-called respirable size fraction has a lung deposition efficiency of 100% at 1 rm or below, 50% at 5 [im, and zero efficiency for particles of 7 jrm and upward (NIOSH 1995). 

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