Method for Improving Ventilation and Gas and Temperature Monitoring with an Advanced Fiber Optic-Based Mine Wide Monitoring System

Details

• Personal Author:
  McFadden J
• Description:
  The system consists of an advanced mine-wide distributed monitoring system utilizing a low power, intrinsically safe, fiber-optic backbone for improving ventilation and gas monitoring in underground mines. The major elements of the system are as follows: 1. A fiber-optic-based methane detection system based on a commercially available product offering from OptoSci Ltd., a spin-off company from the University of Strathclyde in Glasgow, Scotland, focused on the development of innovative photonics technologies arising from internal and academic research. The system is currently in use in landfills and tunnels to monitor methane and natural gas. The system utilizes a low power (10mW) diode laser in conjunction with a distributed fiber network and a series of ruggedized sensor modules. It is largely unaffected by common mine conditions which can cause erroneous readings with many other sensor types including high humidity, anaerobic conditions, and the presence of other non-target gases. The system is tolerant of dust contamination, and fully functioning at signal losses of up to 90%. It can be configured as a distributed network with hundreds of sensing points at distances of up to 20 km from a central control unit. Methane levels from 0.05 to 100% can be accurately measured. Standard communication grade fiber cable is utilized. The system can be deployed in mined-out areas of the mine without risk of creating an ignition source, even in the event of a rock-fall compromising the mechanical enclosure. 2. A fiber-optic based temperature-sensing and monitoring system based on a commercially available product offering from AP Sensing. AP Sensing is a spin-off company from Agilent Technologies with a focus on developing fiber-based remote sensing systems. A low power (17mw) diode laser is utilized to generate an incident light pulse introduced into a single-mode fiber. The backscatter reflected pulse is analyzed. The ratio of the Stokes/anti-Stokes pulse characterizes the temperature rise in the cable, while an OTDR signal provides position data along the monitoring cable. The system utilizes a single leg of communications grade fiber per channel. The sensing range is up to 12 km per channel. The temperature anywhere along the fiber can be monitored within a resolution of approximately 0.5m in location and 1 degree C in magnitude. Various alarm schemes can be configured to look for over-temperature; and rapid temperature rise, as well as breaks in the sensing fiber. A number of interesting applications exist for this technology including belt-line monitoring, cable monitoring, and fire detection. [Description provided by NIOSH]
• Subjects:
  Electricity Fires Mining Occupational Health Safety Temperature
• Keywords:
  Gases Methanes Mine-gases Mining-industry Monitoring-systems Temperature-control Underground-mining Ventilation
• Series:
  Mining Publications
• Publisher:
  National Institute for Occupational Safety and Health
• Document Type:
  Text
• Funding:
  Contract
• Genre:
  Final Contract Report
• Place as Subject:
  Connecticut ; OSHA Region 1 ; OSHA Region 3 ; Pennsylvania
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• NIOSHTIC Number:
  nn:20046360
• Citation:
  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, Contract 200-2012-52515, 2014 Sep; :1-394
• Contact Point Address:
  Jeff McFadden, RSL Fiber Systems LLC, 255 Pitkin Street, East Hartford, CT 06108
• Email:
  jmcfadden@rslfibersystems.com
• CAS Registry Number:
  Methane (CAS RN 74-82-8)
• Federal Fiscal Year:
  2014
• Performing Organization:
  RSL Fiber Systems LLC, East Hartford, Connecticut
• Peer Reviewed:
  False
• Source Full Name:
  National Institute for Occupational Safety and Health
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:2f0ab160a0fe20e0fac4e46817f9f38e16f6d63f6f067438c90b8dec8155b18896da1df927982ac29afcfe07922ada995cca3d73061350289c8a33d85c32cc0d
• Download URL:
  https://stacks.cdc.gov/view/cdc/228136/cdc_228136_DS1.pdf
• File Type:
  [PDF - 8.51 MB ]