Skip directly to site content Skip directly to page options Skip directly to A-Z link Skip directly to A-Z link Skip directly to A-Z link


Centers for Disease Control and Prevention. CDC twenty four seven. Saving Lives, Protecting People
Search
            ×
                        Mining
                        Mining
                            NIOSH
                            All CDC
                    Submit
                For a full list of topics:A-Z Index
                Advanced Search
            Advanced Search


The National Institute for Occupational Safety and Health (NIOSH)


Section Navigation
			
			CDC Home





Mining Publication: Impact on Respirable Dust Levels When Operating a Flooded-bed Scrubber in 20-foot Cuts
Keywords: Continuous miners Dust control Respirable dust Scrubbers
Original creation date: December 2013
Authors: JF Colinet, WR Reed, J Potts
Report of Investigations - December 2013
Download PDF Document (13.20 MB)
NIOSHTIC2 Number: 20043447
Pittsburgh, PA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2014-105, RI 9693, 2013 Dec; :1-59.
Underground coal mining companies that operate continuous miner sections often apply to the Mine Safety and Health Administration (MSHA) for approval to take extended cuts to depths of up to 40 ft as a means of improving productivity. Historically, MSHA has granted approval of this practice if the mine has successfully demonstrated the ability to control the roof, methane, and respirable dust while extracting these extended cuts. A key component for controlling dust generated by continuous miners in 40-ft cuts has been the utilization of flooded-bed scrubbers. These fan-powered scrubbers pull dust-laden air from the mining face and remove respirable dust particles by passing the collected air through a wetted filter panel. The filtered air is then discharged back into the mine atmosphere. To effectively use scrubbers in faces that employ exhaust ventilation, the return ventilation curtain or tubing should be located outby the scrubber discharge on the continuous miner, which results in a setback distance from the face of approximately 40 ft. Over the last several years, MSHA has emphasized that mines demonstrate effective dust control before granting approvals for taking extended cuts with extended curtain setbacks. Each mine operator must successfully demonstrate control of workers’ dust exposures in standard 20-ft cuts before MSHA considers approving extended cuts.
The goal of the research conducted by the National Institute for Occupational Safety and Health (NIOSH) was to compare dust levels generated in 20-ft cuts when using traditional exhaust face ventilation without a scrubber to dust levels in 20-ft cuts when using extended curtain setbacks with a scrubber operating. Dust surveys were completed at three mines, with area and personal sampling conducted to quantify respirable dust concentrations on a cut-by-cut basis. Dust sampling results did not show a statistically significant difference (Wilcoxon two-sample test, α = 0.05) in respirable dust concentrations between these two test conditions (scrubber-on and scrubber-off) at the continuous miner or shuttle car sampling locations at the face. However, with the scrubber operating, respirable dust concentrations in the return airstream downwind of the continuous miner showed reductions of 91%, 86%, and 40% at Mines A, B, and C, respectively. The reductions at Mines A and B were found to be statistically significant when using the Wilcoxon test. Likewise, reductions in respirable quartz dust levels in the continuous miner return were observed at all three mines, with statistically significant reductions of over 80% observed at Mines A and B. Although operation of the flooded-bed scrubber did not impact respirable dust levels in the face area, it did significantly reduce respirable and quartz dust levels downwind of the continuous miner. Consequently, operation of the flooded-bed scrubbers, in conjunction with the dust controls required in the MSHA-approved ventilation plans at these mines, was advantageous from a respirable dust control perspective.
RI 9693. Report of Investigations 2013. Impact on respirable dust levels when operating a flooded-bed scrubber in 20-foot cuts. Cover image shows a visible dust cloud generated by a continuous miner cutting into the coal face. Department of Health and Human Services. Centers for Disease Control and Prevention. National Institute for Occupational Safety and Health. DHHS logo. CDC logo. NIOSH logo.Report of Investigations - December 2013
Download PDF Document (13.20 MB)
NIOSHTIC2 Number: 20043447
Pittsburgh, PA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 2014-105, RI 9693, 2013 Dec; :1-59.
See Also
Control of Respirable Dust
Developing and Improving Respirable Dust Controls in Coal Mines
Dust Underfoot: Enclosed Cab Floor Heaters Can Significantly Increase Operator's Respirable Dust Exposure
Effect of Scrubber Operation on Airflow and Methane Patterns at the Mining Face
Evaluation of the Approach to Respirable Quartz Exposure Control in U.S. Coal Mines
Improved Drill Shroud Capture of Respirable Dust Utilizing Air Nozzles Underneath the Drill Deck
Improving Silica Dust Control Through Targeted Research
Laboratory Testing To Quantify Dust Entrainment During Shield Advance
NIOSH Hazard ID 1 - Exposure to Silica Dust on Continuous Mining Operations Using Flooded-Bed Scrubbers
Performance of a Light Scattering Dust Monitor at Various Air Velocities: Results of Sampling in the Active Versus the Passive Mode
Page last reviewed: November 15, 2016
Page last updated: November 15, 2016
Content source: National Institute for Occupational Safety and Health, Mining Program
Facebook
        Twitter
        LinkedIn
        Syndicate Mining
        Site BrowserSafety and Health TopicsData & StatisticsMethodologyMine DisastersMSHA Data FilesMine & Mineworker ChartsTools & PublicationsTools You Can UsePublicationsNews & ArticlesResearch ProgramNORA Mining CouncilStrategic PlanMining Program, 2019-2023Miner Health Program, 2020-2030ProjectsContractsFunding OpportunitiesMining LinksAbout UsContact NIOSH MiningEmploymentFacilitiesHistoryVisitor Information NIOSH Homepage
 NIOSH A-Z
Workplace Safety & Health Topics
Publications and Products
Programs


About CDC
					Contact Us
					800-232-4636
 Facebook Twitter Instagram LinkedIn Youtube Pinterest Snapchat
 CONTACT CDC
				Contact Us
							Call 800-232-4636
							Email Us
			ABOUT CDC
				About CDC
							Jobs
							Funding
			POLICIES
				Accessibility
							External Links
							Privacy
							Policies
							No Fear Act
							FOIA
							OIG
							Nondiscrimination
							Vulnerability Disclosure Policy
			CONNECT WITH US
				Facebook
								Twitter
								Instagram
								LinkedIn
							Youtube
								Pinterest
								Snapchat
								Email
			LANGUAGES
				Español
							繁體中文
							Tiếng Việt
							한국어
							Tagalog
							Русский
							العربية
							Kreyòl Ayisyen
							Français
							Polski
							Português
							Italiano
							Deutsch
							日本語
							فارسی
							English


U.S. Department of Health & Human Services
			Accessibility
			External Links
			Privacy
			Policies
			No Fear Act
			FOIA
			Nondiscrimination
			OIG
			Vulnerability Disclosure Policy
			USA.gov


Exit Notification / Disclaimer Policy Close
 Links with this icon  indicate that you are leaving the CDC website. The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website.
				Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website.
				You will be subject to the destination website's privacy policy when you follow the link.
				CDC is not responsible for Section 508 compliance (accessibility) on other federal or private website. Website Disclaimers
 Cancel Continue